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Qu LP, Dong G, Chen J, Xiao J, De Boeck HJ, Chen J, Jiang S, Batkhishig O, Legesse TG, Xin X, Shao C. Soil environmental anomalies dominate the responses of net ecosystem productivity to heatwaves in three Mongolian grasslands. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 944:173742. [PMID: 38839012 DOI: 10.1016/j.scitotenv.2024.173742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 05/28/2024] [Accepted: 06/01/2024] [Indexed: 06/07/2024]
Abstract
Climate change is causing more frequent and intense heatwaves. Therefore, it is important to understand how heatwaves affect the terrestrial carbon cycle, especially in grasslands, which are especially susceptible to climate extremes. This study assessed the impact of naturally occurring, simultaneous short-term heatwaves on CO2 fluxes in three ecosystems on the Mongolia Plateau: meadow steppe (MDW), typical steppe (TPL), and shrub-grassland (SHB). During three heatwaves, net ecosystem productivity (NEP) was reduced by 86 %, 178 %, and 172 % at MDW, TPL, and SHB, respectively. The changes in ecosystem respiration, gross primary production, evapotranspiration, and water use efficiency were divergent, indicating the mechanisms underlying the observed NEP decreases among the sites. The impact of the heatwave in MDW was mitigated by the high soil water content, which enhanced evapotranspiration and subsequent cooling effects. However, at TPL, insufficient soil water led to combined thermal and drought stress and low resilience. At SHB, the ecosystem's low tolerance to an August heatwave was heavily influenced by species phenology, as it coincided with the key phenological growing phase of plants. The potential key mechanism of divergent NEP response to heatwaves lies in the divergent stability and varying importance of environmental factors, combined with the specific sensitivity of NEP to each factor in ecosystems. Furthermore, our findings suggest that anomalies in soil environment, rather than atmospheric anomalies, are the primary determinants of NEP anomalies during heatwaves. This challenges the conventional understanding of heatwaves as a discrete and ephemeral periods of high air temperatures. Instead, heatwaves should be viewed as chronologically variable, compound, and time-sensitive environmental stressors. The ultimate impact of heatwaves on ecosystems is co-determined by a complex interplay of environmental, biological, and heatwave features.
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Affiliation(s)
- Lu-Ping Qu
- College of JunCao Science and Ecology, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Gang Dong
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; School of Life Science, Shanxi University, Taiyuan, China
| | - Jiquan Chen
- Department of Geography, Environment, and Spatial Sciences, Michigan State University, East Lansing, MI 48823, USA
| | - Jingfeng Xiao
- Earth Systems Research Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH 03824, USA
| | - Hans J De Boeck
- Research Group of Plants and Ecosystems (PLECO), Department of Biology, University of Antwerp, 2610 Wilrijk, Belgium; School of Ecology and Environmental Sciences, Yunnan University, Kunming 650091, China
| | - Jingyan Chen
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Shicheng Jiang
- Key Laboratory of Vegetation Ecology, Ministry of Education, Northeast Normal University, Changchun, China
| | - Ochirbat Batkhishig
- Institute of Geography, Mongolian Academy of Sciences, Ulaanbaartar 210620, Mongolia
| | - Tsegaye Gemechu Legesse
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Xiaoping Xin
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Changliang Shao
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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Zheng S, Peng D, Zhang B, Yu L, Pan Y, Wang Y, Feng X, Dou C. Temporal variation characteristics in the association between climate and vegetation in Northwest China. Sci Rep 2024; 14:17905. [PMID: 39095561 PMCID: PMC11297244 DOI: 10.1038/s41598-024-68066-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 07/19/2024] [Indexed: 08/04/2024] Open
Abstract
Northwest China has undergone notable alterations in climate and vegetation growth in recent decades. Nevertheless, uncertainties persist concerning the response of different vegetation types to climate change and the underlying mechanisms. This study utilized the Normalized Difference Vegetation Index (NDVI) and three sets of meteorological data to investigate the interannual variations in the association between vegetation and climate (specifically precipitation and temperature) from 1982 to 2015. Several conclusions were drawn. (1) RNDVI-GP (relationship between Growing Season NDVI and precipitation) decreased significantly across all vegetation, while RNDVI-GT (relationship between Growing Season NDVI and temperature) showed an insignificant increase. (2) Trends of RNDVI-GP and RNDVI-GT exhibited great variations across various types of vegetation, with forests displaying notable downward trends in both indices. The grassland exhibited a declining trend in RNDVI-GP but an insignificant increase in RNDVI-GT, while no significant temporal changes in RNDVI-GP or RNDVI-GT were observed in the barren land. (3) The fluctuations in RNDVI-GP and RNDVI-GT closely aligned with variations in drought conditions. Specifically, in regions characterized by VPD (vapor pressure deficit) trends less than 0.02 hpa/yr, which are predominantly grasslands, a rise in SWV (soil water volume) tended to cause a reduction in RNDVI-GP but an increase in RNDVI-GT. However, a more negative trend in SWV was associated with a more negative trend in both RNDVI-GP and RNDVI-GT when the VPD trend exceeded 0.02 hPa/yr, primarily in forests. Our results underscore the variability in the relationship between climate change and vegetation across different vegetation types, as well as the role of drought in modulating these associations.
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Affiliation(s)
- Shijun Zheng
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, 100084, China
| | - Dailiang Peng
- Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, 100094, China.
- International Research Center of Big Data for Sustainable Development Goals, Beijing, 100094, China.
| | - Bing Zhang
- Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, 100094, China
- International Research Center of Big Data for Sustainable Development Goals, Beijing, 100094, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Le Yu
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, 100084, China.
| | - Yuhao Pan
- Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, 100094, China
- International Research Center of Big Data for Sustainable Development Goals, Beijing, 100094, China
| | - Yan Wang
- Department of Land Surveying and Geo-Informatics, The Hong Kong Polytechnic University, Hong Kong, 999077, China
| | - Xuxiang Feng
- China Remote Sensing Satellite Ground Station (RSGS), Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, 100094, China
| | - Changyong Dou
- Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, 100094, China
- International Research Center of Big Data for Sustainable Development Goals, Beijing, 100094, China
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Li J, Han W, Zheng J, Yu X, Tian R, Liu L, Guan J. Grassland productivity in arid Central Asia depends on the greening rate rather than the growing season length. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 933:173155. [PMID: 38735323 DOI: 10.1016/j.scitotenv.2024.173155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 05/07/2024] [Accepted: 05/09/2024] [Indexed: 05/14/2024]
Abstract
Climate change has induced substantial impact on the gross primary productivity (GPP) of terrestrial ecosystems by affecting vegetation phenology. Nevertheless, it remains unclear which among the mean rates of grass greening (RG), yellowing (RY), and the length of growing season (LOS) exhibit stronger explanatory power for GPP variations, and how RG and RY affect GPP variations under warming scenarios. Here, we explored the relationship between RG, RY, LOS, and GPP in arid Central Asia (ACA) from 1982 to 2019, elucidating the response mechanisms of RG, RY, and GPP to the mean temperature (TMP), vapor pressure deficit (VPD), precipitation (PRE), and soil moisture (SM). The results showed that the multi-year average length of greening (LG) in ACA was 22.7 days shorter than that of yellowing (LY) and the multi-year average GPP during LG (GPPlg) was 38.28 g C m-2 d -1 more than that of during LY (GPPly). RG and RY were positively correlated with GPPlg and GPPly, although the degree of correlation between RG and GPPlg was higher than that between RY and GPPly. Increases in RG and RY contributed to an increase in GPPlg (55.44 % of annual GPP) and GPPly (35.44 % of annual GPP). The correlation between RG and GPPlg was the strongest (0.49), followed by RY and GPPly (0.33), and LOS and GPP was the weakest (0.21). TMP, VPD, PRE, and SM primarily affected GPP by influencing RG and RY, rather than direct effects. The positive effects of TMP during LG (TMPlg), PRE during LG (PRElg), and SM during LG (SMlg) facilitated increases in RG and GPPlg, and higher VPD during LY (VPDly) and lower PRE during LY (PREly) accelerated increases in RY. Our study elucidated the impact of vegetation growth rate on GPP, thus providing an alternate method of quantifying the relationship between vegetation phenology and GPP.
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Affiliation(s)
- Jianhao Li
- College of Geography and Remote Sensing Sciences, Xinjiang University, Urumqi 830046, China
| | - Wanqiang Han
- College of Geography and Remote Sensing Sciences, Xinjiang University, Urumqi 830046, China
| | - Jianghua Zheng
- College of Geography and Remote Sensing Sciences, Xinjiang University, Urumqi 830046, China; Xinjiang Key Laboratory of Oasis Ecology, Xinjiang University, Urumqi 830046, China.
| | - Xiaojing Yu
- College of Geography and Remote Sensing Sciences, Xinjiang University, Urumqi 830046, China
| | - Ruikang Tian
- College of Geography and Remote Sensing Sciences, Xinjiang University, Urumqi 830046, China
| | - Liang Liu
- College of Geography and Remote Sensing Sciences, Xinjiang University, Urumqi 830046, China
| | - Jingyun Guan
- College of Tourism, Xinjiang University of Finance & Economics, Urumqi 830012, China
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Li P, Zhu W, He B. Regional differences in the impact paths of climate on aboveground biomass in alpine grasslands across the Qinghai-Tibet Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 947:174421. [PMID: 38972405 DOI: 10.1016/j.scitotenv.2024.174421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Revised: 06/26/2024] [Accepted: 06/29/2024] [Indexed: 07/09/2024]
Abstract
Alpine grasslands on the Qinghai-Tibet Plateau (QTP) play an essential role in water conservation, biodiversity protection and climate feedback, with aboveground biomass (AGB) serving as a crucial indicator of grassland health and functionality. While previous studies have independently explored the phenological differences, cumulative effects, and spatial variability of climatic impacts on biomass/productivity in alpine grasslands, the cascading effects regarding climate and phenology on AGB still present knowledge gaps. Here, using peak AGB measurements, remote sensing and gridded climate data in the QTP alpine grasslands during 2002-2018, we systematically analyzed the impact paths of climatic variables (i.e., cumulative precipitation, CP; growing degree-days, GDD) and phenology-mediated paths (start and peak date of the growing season, SOS and POS) on AGB and their regional differences. During the preseason (pre60) or the growing season (sos-pos), climate primarily directly impacted variations in AGB across different climatic regions, although a phenology-mediated path by which climate indirectly affected AGB existed (i.e., GDDsos-pos → POS → AGB). Three general patterns were revealed: In the plateau temperate arid regions, an increase in CPpre60 significantly promoted AGB (path coefficients w = 0.61-0.71), whereas an increase in GDDpre60 inhibited AGB (w = -0.42 ~ -0.49); In the plateau sub-cold regions, increases in both CPsos-pos and GDDsos-pos significantly promoted AGB, respectively (w = 0.46-0.81 and w = 0.37-0.70); Similarly, in the plateau temperate arid or semi-arid regions, increases in CPsos-pos also significantly promoted the AGB (w = 0.56-0.73). This study highlights that the water and heat accumulation mainly exert direct impacts on alpine grassland AGB across various climatic regions and phenological stages, providing insights into the mechanism driving AGB by climate and phenology during spring and summer.
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Affiliation(s)
- Peixian Li
- ASEAN-China Satellite Remote Sensing Application Centre (Ocean Remote Sensing Center), Fourth Institute of Oceanography, Ministry of Natural Resources, Beihai 536000, China; Guangxi Key Laboratory of Beibu Gulf Marine Resources, Environment and Sustainable Development, Fourth Institute of Oceanography, Ministry of Natural Resources, Beihai 536000, China; Beijing Engineering Research Center for Global Land Remote Sensing Products, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
| | - Wenquan Zhu
- State Key Laboratory of Remote Sensing Science, Beijing Normal University, Beijing 100875, China; Beijing Engineering Research Center for Global Land Remote Sensing Products, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China.
| | - Bangke He
- State Key Laboratory of Remote Sensing Science, Beijing Normal University, Beijing 100875, China; Beijing Engineering Research Center for Global Land Remote Sensing Products, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
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5
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Bao Y, Tian H, Wang X. Effects of climate change and ozone on vegetation phenology on the Tibetan Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 932:172780. [PMID: 38685428 DOI: 10.1016/j.scitotenv.2024.172780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 05/02/2024]
Abstract
The vegetation phenology, encompassing the start (SOS) and end (EOS) of the growing season on the Tibetan Plateau, has been significantly impacted by global climate change. Furthermore, ozone (O3) has gradually become the main pollutant in this region, substantially influencing carbon cycle and ecosystems on Earth. While ongoing studies have focused mainly on the implications of climate parameters, including temperature, precipitation, and radiation, the effects of O3 on the SOS and EOS remain unclear. Here, we compared the responses and sensitivities of the SOS and EOS to both climatic factors and O3 in this region. With the use of partial correlation analysis, we found that increased precipitation was the most important factor influencing the SOS and caused earlier occurrence (4.8 % vs. 21.9 %) for most plant functional types. In comparison, temperature only dominated in shrublands. In particular, we found that the EOS responded comparably to climatic factors with similar proportions between advancing and delaying patterns. However, higher O3 levels consistently advanced the EOS for almost all plant functional types and was the main factor controlling EOS variations based on the sensitivity analysis. Our results emphasized that O3 pollution should be considered for obtaining better phenological forecasts and determining the impacts of the environment and atmospheric composition on carbon sequestration in terrestrial ecosystems.
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Affiliation(s)
- Yanlei Bao
- School of Geographical Sciences, Hebei Normal University, Shijiazhuang 050024, China; Department of Hydraulic Engineering, Hebei University of Water Resources and Electric Engineering, Cangzhou 061001, China
| | - Haifeng Tian
- College of Geography and Environmental Science, Henan University, Kaifeng 475004, China
| | - Xiaoyue Wang
- The Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
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Fan W, Luo Y. Impacts of Climate Change on the Distribution of Suitable Habitats and Ecological Niche for Trollius Wildflowers in Ili River Valley, Tacheng, Altay Prefecture. PLANTS (BASEL, SWITZERLAND) 2024; 13:1752. [PMID: 38999591 PMCID: PMC11243624 DOI: 10.3390/plants13131752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 06/15/2024] [Accepted: 06/18/2024] [Indexed: 07/14/2024]
Abstract
Xinjiang in China is distinguished by its distinctive regional landscape and high ecological sensitivity. Trollius wildflowers represent a unique and iconic element of the mountain flower landscape in Xinjiang. However, their populations are predominantly distributed in mountainous areas, making them susceptible to climate change. Despite this, the impacts of climate change on the distribution of suitable habitats and ecological niche differentiation for Trollius wildflowers have rarely been quantified. Consequently, simulations were conducted using the R-optimized MaxEnt model to predict the suitable habitat distribution of Trollius wildflowers. This was based on the occurrence data and environmental variables for the four species of Trollius (T. altaicus, T. asiaticus, T. dschungaricus, and T. lilacinus) that exist in the study area. The simulation was conducted over a period of time, beginning with the past glacial period and extending to the present, and then to the future (2050s, 2070s, and 2090s) under multiple scenarios (SSP1-2.6, SSP3-7.0, SSP5-8.5). The simulation of suitable habitats enabled the measurement of the ecological niche breadth and differentiation. The results demonstrate that the model predictions are precisely accurate, with AUC values exceeding 0.9. Annual mean temperature (Bio1), isothermality (Bio3), and precipitation in the warmest quarter (Bio18) are the dominant climate variables, in addition to vegetation, elevation, and soil factors. The proportion of suitable habitats for Trollius wildflowers varies considerably over time, from 0.14% to 70.97%. The majority of habitat loss or gain occurs at the edges of mountains, while stable habitats are concentrated in the core of the mountains. The gravity center of suitable habitats also shifts with spatial transfer, with the shifts mainly occurring in a northeasterly-southwesterly direction. The SSP1-2.6 scenario results in the sustained maintenance of habitats, whereas the SSP3-7.0 and SSP5-8.5 scenarios present challenges to the conservation of habitats. The threshold of ecological niche breadth for Trollius wildflowers is subject to fluctuations, while the ecological niche differentiation also varies. The study aims to examine the evolution of the habitat and ecological niche of Trollius wildflowers in Xinjiang under climate change. The findings will provide theoretical support for delineating the conservation area, clarify the scope of mountain flower tourism development and protection of mountain flower resources, and promote the sustainable development of ecotourism and effective utilization of territorial space in Xinjiang.
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Affiliation(s)
- Wenhao Fan
- School of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Yanyun Luo
- School of Architecture and Environment, Sichuan University, Chengdu 610065, China
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7
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Cong N, Du Z, Zheng Z, Zhao G, Sun D, Zu J, Zhang Y. Altitude explains insignificant autumn phenological changes across regions with large topography relief in the Tibetan Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 921:171088. [PMID: 38387561 DOI: 10.1016/j.scitotenv.2024.171088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 02/15/2024] [Accepted: 02/17/2024] [Indexed: 02/24/2024]
Abstract
The start of the growing season (SGS) and the end of the growing season (EGS) are widely employed in global change studies to represent the spring and autumn phenology, respectively. Despite the Tibetan Plateau (TP) experiencing significant warming in recent decades, EGS has exhibited only slight changes. Previous studies have concentrated on exploring the environmental regulation of phenology, ignoring the distinctive influences of elevation. Therefore, a more in-depth investigation into the underlying mechanism is warranted. In this study, we investigate the variability of EGS among alpine vegetation regions at different elevations and conduct an analysis based on satellite data. Phenology data of alpine vegetation are extracted from SPOT NDVI dataset spanning from 1999 to 2018, using a piecewise-logistic-maximum-ratio method. We analyze the factors influencing EGS trends at different elevations. The results show that the overall insignificant variation in EGS is mainly attributed to altitude. With the altitude increasing, the annual mean EGS experiences a delay of 0.28 days/100 m below 3500 m, while it advances by 0.2 days/100 m above 3500 m. The opposing shift in elevation below and above 3500 m leads to this counteraction. Elevation emerges as the predominant factor influencing EGS trends, explaining the highest variations (38 %), followed by SGS (22 %) and precipitation (22 %). The elevation effect is most pronounced in areas with substantial topography fluctuations. Moreover, the elevation lapse rate of EGS (ELR_EGS) exhibits an opposite trend with growing season (GS) temperature and a similar trend with GS precipitation between the regions below and above 3500 m, ultimately linking to this counteraction. This study underscores elevation is a critical regulator of vegetation EGS responses to climatic changes over the TP, revealing significant spatial heterogeneities in these responses.
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Affiliation(s)
- Nan Cong
- Lhasa Plateau Ecosystem Research Station, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhiyong Du
- Lhasa Plateau Ecosystem Research Station, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Zhoutao Zheng
- Lhasa Plateau Ecosystem Research Station, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Guang Zhao
- Lhasa Plateau Ecosystem Research Station, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Dongqi Sun
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Jiaxing Zu
- Key Laboratory of Environment Change and Resources Use in Beibu Gulf, Ministry of Education, Nanning Normal University, Nanning 530001, China
| | - Yangjian Zhang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China; Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
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8
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Zhao Z, Dai E. Vegetation cover dynamics and its constraint effect on ecosystem services on the Qinghai-Tibet Plateau under ecological restoration projects. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 356:120535. [PMID: 38479287 DOI: 10.1016/j.jenvman.2024.120535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 02/01/2024] [Accepted: 02/29/2024] [Indexed: 04/07/2024]
Abstract
Ecological restoration projects (ERPs) are implemented worldwide to restore degraded ecosystems and promote ecosystem sustainability. In recent years, a series of ERPs have been implemented to enhance vegetation cover in the unique alpine ecosystems of the Qinghai-Tibet Plateau (QTP). However, the current assessment of the ecological benefits of ERPs is relatively single, and the scale and extent of future ecological restoration project implementation cannot be determined. We quantified trends in normalized vegetation index (NDVI) since the implementation of ERPs. Changes in four major ecosystem services were assessed before and after ERPs implementation, including wind erosion protection, soil retention, water yield, and net primary productivity (NPP). The relationship between NDVI and ecosystem services was further explored using a constraint line approach to identify NDVI as a threshold reference for ERPs implementation. The results showed that: (1) since the implementation of ERPs, 21.80% of the regional NDVI of the QTP has increased significantly. (2) After the implementation of ERPs, the average total ecosystem services index (TES) increased from 0.269 in 2000 to 0.285 in 2020. The average soil retention and water yield increased but the NPP and sandstorm prevention decreased slightly. (3) NDVI had no significant constraint effect on soil retention and NPP, but there was a significant constraint effect on wind erosion prevention and water yield. (4) The constraint line of NDVI on TES was S-shaped. After the implementation of ERPs, the TES gradually reached a threshold value when NDVI was 0.65-0.75. Our findings identify significant contributions of ERPs and thresholds for the constraining effects of vegetation cover on ecosystem services, which can inform sustainable ERPs for governments.
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Affiliation(s)
- Zhongxu Zhao
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Erfu Dai
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.
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9
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Wu Y, Li F, Zhang J, Liu Y, Li H, Zhou B, Shen B, Hou L, Xu D, Ding L, Chen S, Liu X, Peng J. Spatial and temporal patterns of above- and below- ground biomass over the Tibet Plateau grasslands and their sensitivity to climate change. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 919:170900. [PMID: 38354804 DOI: 10.1016/j.scitotenv.2024.170900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 01/22/2024] [Accepted: 02/09/2024] [Indexed: 02/16/2024]
Abstract
The sensitivity of grassland above- (AGB, gC m-2) and below-ground biomass (BGB, gC m-2) to climate has been shown to be significant on the Tibetan Plateau, however, the spatial patterns and sensitivity of biomass with altitudinal change needs to be quantitated. In this study, large data sets of AGB and BGB during the peak growth season, and the corresponding geographical and climate conditions in the grasslands of the Tibetan Plateau between 2001 and 2020 were analyzed, and modelled using a Cubist regression trees algorithm. The mean values for AGB and BGB were 61.3 and 1304.3 gC m-2, respectively, for the whole region over the two decades. There was a significant change in spatial AGB of 64.8 % on the Plateau (P < 0.05, with areas where AGB increased being twice as large as areas where AGB decreased), while BGB did not change significantly in majority the of the region (≥ 90.1 %, P > 0.05). In general, the areas where AGB showed positive partial correlations with precipitation were larger than the areas where AGB had positive correlations with temperature (P < 0.05). However, these trends varied depending on the climatic conditions: in the wetter regions, temperature had a greater effect on the size of the areas with positive AGB responses than precipitation (P < 0.05), while precipitation had a greater effect on the size of areas with positive BGB changes than temperature (P < 0.05). In the drier areas, however, precipitation affected the AGB response significantly compared to temperature (P < 0.05), while temperature influenced the BGB response greater than precipitation (P < 0.05). The response and sensitivity of grassland biomass to temperature and precipitation varied according to the altitude of the Plateau: the response and sensitivity were stronger and more sensitive at medium altitudes, and weak at the higher or lower altitudes. Likely, this phenomenon was resulted from the natural selection of plants to maintain the efficient use of resources during un-favourable and stressed conditions for maximum plant development and growth. These findings will help assess the ecological consequences of global climate change for the grasslands of the Tibetan Plateau, particularly in those regions with highly variable altitudes.
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Affiliation(s)
- Yatang Wu
- Key Laboratory of Grassland Ecosystem, Ministry of Education, Sino-U.S. Centers for Grazing Land Ecosystem Sustainability, Ministry of Science and Technology, Pratacultural Engineering Laboratory of Gansu Province, Pratacultural College, Gansu Agricultural University, Lanzhou 730070, China
| | - Fu Li
- Qinghai Institute of Meteorological Sciences, Xining 810001, China
| | - Jing Zhang
- National Remote Sensing Center of China, No. 8A Liulinguan Nanli, Haidian District, Beijing 100036, China
| | - YiLiang Liu
- National Remote Sensing Center of China, No. 8A Liulinguan Nanli, Haidian District, Beijing 100036, China
| | - Han Li
- National Remote Sensing Center of China, No. 8A Liulinguan Nanli, Haidian District, Beijing 100036, China
| | - Bingrong Zhou
- Qinghai Institute of Meteorological Sciences, Xining 810001, China
| | - Beibei Shen
- Aerospace Science and Industry (Beijing) Spatial Information Application Co., Ltd., Beijing 100070, China; State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Lulu Hou
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Dawei Xu
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Lei Ding
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shiyang Chen
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Xiaoni Liu
- Key Laboratory of Grassland Ecosystem, Ministry of Education, Sino-U.S. Centers for Grazing Land Ecosystem Sustainability, Ministry of Science and Technology, Pratacultural Engineering Laboratory of Gansu Province, Pratacultural College, Gansu Agricultural University, Lanzhou 730070, China.
| | - Jinbang Peng
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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10
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Liu Y, Zhang X, Du X, Du Z, Sun M. Alpine grassland greening on the Northern Tibetan Plateau driven by climate change and human activities considering extreme temperature and soil moisture. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 916:169995. [PMID: 38242484 DOI: 10.1016/j.scitotenv.2024.169995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 12/24/2023] [Accepted: 01/05/2024] [Indexed: 01/21/2024]
Abstract
Alpine grassland is among the world's most vulnerable ecosystems, characterized by a high sensitivity to climate change (CC) and human activities (HA). Quantifying the relative contributions of CC and HA to grassland change plays a crucial role in safeguarding grassland ecological security and devising sustainable grassland management strategies. Although there were adequate studies focusing on the separate impacts of CC and HA on alpine ecosystem, insufficient attention has been given to investigating the effects of extreme temperatures and soil moisture. In this study, the spatiotemporal variations of alpine grassland were analyzed based on MODIS NDVI during the growing season from 2000 to 2020 in Naqu, using partial least squares regression and residual analysis methods to analyze the importance of climate factors and the impacts of CC and HA on grassland change. The results show that the NDVI during the growing season in Naqu exhibited an increasing trend of 0.0046/10a. At the biome scale, the most significant and rapid increase was observed in alpine desert and alpine desert grassland. Extreme temperature and soil moisture (SM) exerted a more significant importance on alpine grassland at whole scale. SM always showed a significant importance at biome and grid scale. The contributions of CC and HA to the change during the growing season were calculated as 0.0032/10a and 0.0015/10a, respectively, accounting for 68.05 % and 31.05 %. CC dominated the increase in NDVI during the growing season; HA contributed positively to NDVI in most areas of Naqu. The results are expected to enhance our understanding of grassland variations under CC and HA and provide a scientific basis for future ecological conservation in alpine regions.
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Affiliation(s)
- Yuanguo Liu
- School of Public Administration, Hohai University, Nanjing, China
| | - Xiaoke Zhang
- School of Public Administration, Hohai University, Nanjing, China; Center for Environmental and Social Studies, Hohai University, Nanjing, China.
| | - Xindong Du
- School of Public Administration, Hohai University, Nanjing, China
| | - Ziyin Du
- School of Land and Resources, China West Normal University, Nanchong, China
| | - Mingze Sun
- School of Public Administration, Hohai University, Nanjing, China
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11
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Dastigerdi M, Nadi M, Sarjaz MR, Kiapasha K. Trend analysis of MODIS NDVI time series and its relationship to temperature and precipitation in Northeastern of Iran. ENVIRONMENTAL MONITORING AND ASSESSMENT 2024; 196:346. [PMID: 38443602 DOI: 10.1007/s10661-024-12463-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 02/17/2024] [Indexed: 03/07/2024]
Abstract
Vegetation plays a crucial role in providing organic matter and regulating energy exchange on the Earth's surface. This study investigates the changes in vegetation cover, temperature, and precipitation in northeastern Iran during 2001-2020. MODIS-NDVI time series data and climatic data from 11 synoptic stations were utilized. The nonparametric Mann-Kendall method was employed to detect trends in vegetation cover and climatic variables. Additionally, the correlation between climatic parameters and vegetation was examined. Trend analysis revealed significant increases/decreases in vegetation cover in 32%/26% of the region, respectively. The increasing trend in vegetation cover was predominantly observed in highlands, suggesting that a warmer climate has enhanced the living conditions for plants in these regions. The vegetation trend map indicates an expansion of vegetation cover in the northern and central parts of Iran during the past 20 years, whereas the southern and eastern portions experienced declines. The relationship between vegetation and elevation revealed that vegetation increased above 1,850 m and decreased below 850 m. Trend analysis showed no significant trend in precipitation data since the beginning of the twenty-first century, but an increasing trend in temperature was observed in 82% of the region's area, excluding the western strip. Correlation coefficients between temperature, precipitation, and vegetation indicated that declining temperatures are the limiting factors for vegetation in the highlands, while in lowland areas, the decrease in precipitation significantly diminishes vegetation growth.
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Affiliation(s)
- Morteza Dastigerdi
- Department of Water Engineering, Sari Agricultural sciences and Natural Resources University, Sari, Iran
| | - Mehdi Nadi
- Department of Water Engineering, Sari Agricultural sciences and Natural Resources University, Sari, Iran.
| | - Mahmoud Raeini Sarjaz
- Department of Water Engineering, Sari Agricultural sciences and Natural Resources University, Sari, Iran
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12
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Behroozian M, Pierce S, Ejtehadi H, Memariani F, Rafiee F, Joharchi MR. Relative contributions of taxonomic and functional diversity to the assembly of plant communities hosting endemic Dianthus species in a mountain steppe. Sci Rep 2024; 14:5471. [PMID: 38443610 PMCID: PMC10915155 DOI: 10.1038/s41598-024-56099-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 03/01/2024] [Indexed: 03/07/2024] Open
Abstract
Plant community assembly is the outcome of long-term evolutionary events (evident as taxonomic diversity; TD) and immediate adaptive fitness (functional diversity; FD); a balance expected to shift in favour of FD in 'harsh' habitats under intense selection pressures. We compared TD and FD responses along climatic and edaphic gradients for communities of two species (Dianthus pseudocrinitus and D. polylepis) endemic to the montane steppes of the Khorassan-Kopet Dagh floristic province, NE Iran. 75 plots at 15 sites were used to relate TD and FD to environmental gradients. In general, greater TD was associated with variation in soil factors (potassium, lime, organic matter contents), whereas FD was constrained by aridity (drought adaptation). Crucially, even plant communities hosting different subspecies of D. polylepis responded differently to aridity: D. polylepis subsp. binaludensis communities included a variety of broadly stress-tolerant taxa with no clear environmental response, but TD of D. polylepis subsp. polylepis communities was directly related to precipitation, with consistently low FD reflecting a few highly specialized stress-tolerators. Integrating taxonomic and functional diversity metrics is essential to understand the communities hosting even extremely closely related taxa, which respond idiosyncratically to climate and soil gradients.
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Affiliation(s)
| | - Simon Pierce
- Department of Agricultural and Environmental Sciences (DiSAA), University of Milan, Via G. Celoria 2, 20133, Milan, Italy
| | - Hamid Ejtehadi
- Quantitative Plant Ecology and Biodiversity Research Laboratory, Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Farshid Memariani
- Herbarium FUMH, Ferdowsi University of Mashhad, Mashhad, Iran
- Department of Range and Watershed Management, Faculty of Natural Resources and Environment, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Fahime Rafiee
- Quantitative Plant Ecology and Biodiversity Research Laboratory, Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
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13
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Zhong R, Yan K, Gao S, Yang K, Zhao S, Ma X, Zhu P, Fan L, Yin G. Response of grassland growing season length to extreme climatic events on the Qinghai-Tibetan Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 909:168488. [PMID: 37972770 DOI: 10.1016/j.scitotenv.2023.168488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 11/08/2023] [Accepted: 11/09/2023] [Indexed: 11/19/2023]
Abstract
Extreme Climatic Events (ECEs) are increasing in intensity, frequency, and duration as the earth warms, which greatly affects the vegetation phenology. However, the response of vegetation phenology to different types of ECEs (e.g., extreme hot, extreme cold, extreme drought, and extreme wet) has not been extensively studied. To fill this knowledge gap, we investigated the relationship between the length of growing season (LOS) of grassland and ECEs on the Qinghai-Tibetan Plateau (QTP). First, we analyzed the spatial distribution and interannual trends of phenology based on the MODIS Normalized Difference Vegetation Index (NDVI). Second, we used Coincidence Rate (CR) analysis to quantify the relationship between LOS anomalies and ECEs. Finally, we analyzed the sensitivity of LOS to the intensity of ECEs. The results indicated that the spatial distribution of LOS was closely related to local hydrothermal conditions, with longer LOS in places with more precipitation or higher temperatures during the growing season, and LOS extended by 0.28 days/year from 2000 to 2022. Moreover, we found that the CR of negative LOS anomalies to ECEs notably exhibited variations along climatic gradients, with higher CR to extreme hot generally occurring in warmer areas. Meanwhile, the CR of extreme wet increased while the CR of extreme drought decreased with increasing precipitation. We also found that the sensitivity of LOS to ECEs changed more markedly, along the climatic gradients, in alpine ecoregions compared to temperate ecoregions. Overall, the sensitivities of LOS ranked in descending order of absolute sensitivity to extreme drought, extreme wet, extreme hot, and extreme cold. This study furthers our understanding of the grassland response to ECEs under different hydrothermal conditions, which can provide valuable reference for the management and conservation of grassland ecosystems in QTP under future climate change scenarios.
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Affiliation(s)
- Run Zhong
- Innovation Research Center of Satellite Application (IRCSA), Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China; School of Land Science and Techniques, China University of Geosciences, Beijing 100083, China
| | - Kai Yan
- Innovation Research Center of Satellite Application (IRCSA), Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China; School of Land Science and Techniques, China University of Geosciences, Beijing 100083, China.
| | - Si Gao
- Innovation Research Center of Satellite Application (IRCSA), Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China; School of Land Science and Techniques, China University of Geosciences, Beijing 100083, China
| | - Kai Yang
- Innovation Research Center of Satellite Application (IRCSA), Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China; School of Land Science and Techniques, China University of Geosciences, Beijing 100083, China
| | - Shuang Zhao
- Innovation Research Center of Satellite Application (IRCSA), Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
| | - Xuanlong Ma
- College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730020, China
| | - Peng Zhu
- Institute for Climate and Carbon Neutrality, Department of Geography, The University of Hong Kong, Hong Kong
| | - Lei Fan
- Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station, School of Geographical Sciences, Southwest University, Chongqing 400715, China
| | - Gaofei Yin
- Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu 610031, China
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14
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Li J, Wei J, Shao X, Yan X, Liu K. Effective microorganisms input efficiently improves the vegetation and microbial community of degraded alpine grassland. Front Microbiol 2024; 14:1330149. [PMID: 38298535 PMCID: PMC10829099 DOI: 10.3389/fmicb.2023.1330149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 12/27/2023] [Indexed: 02/02/2024] Open
Abstract
Soil beneficial microorganism deficiency in the degraded grasslands have emerged as the major factors negatively impacting soil quality and vegetation productivity. EM (effective microorganisms) has been regarded as a good ameliorant in improving microbial communities and restoring degraded soil of agricultural systems. However, knowledge was inadequate regarding the effects of adding EM on the degraded alpine grassland. Four levels of EM addition (0, 150, 200, 250 mL m-2) were conducted to investigate the effects of EM addition on soil properties and microorganisms of degraded alpine grassland. The addition of EM increased aboveground biomass, soil organic carbon, total nitrogen, available phosphorus, and microbial biomass, but decreased soil electric conductivity. Meanwhile, the relative biomasses of gram-negative bacteria decreased, while the ectomycorrhizal fungi and arbuscular mycorrhizal fungi increased after EM addition. The relationship between microbial communities and environmental factors has been changed. The restore effect of EM increased with the increase of addition time. These results indicated that EM addition could be a good practice to restore the health of the degraded alpine grassland ecosystem.
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Affiliation(s)
- Jinsheng Li
- School of Resources and Environment, Anhui Agricultural University, Hefei, Anhui, China
- College of Grassland Science and Technology, China Agricultural University, Beijing, China
| | - Juping Wei
- School of Resources and Environment, Anhui Agricultural University, Hefei, Anhui, China
| | - Xinqing Shao
- College of Grassland Science and Technology, China Agricultural University, Beijing, China
| | - Xinhui Yan
- College of Grassland Science and Technology, China Agricultural University, Beijing, China
| | - Kesi Liu
- College of Grassland Science and Technology, China Agricultural University, Beijing, China
- Key Laboratory of Restoration Ecology of Cold Area in Qinghai Province, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
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15
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Lü D, Lü Y, Gao G, Sun S, Wang Y, Fu B. A landscape persistence-based methodological framework for assessing ecological stability. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2024; 17:100300. [PMID: 37560752 PMCID: PMC10407666 DOI: 10.1016/j.ese.2023.100300] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 07/06/2023] [Accepted: 07/09/2023] [Indexed: 08/11/2023]
Abstract
Ecological stability is a critical factor in global sustainable development, yet its significance has been overlooked. Here we introduce a landscape-oriented framework to evaluate ecological stability in the Qingzang Plateau (QP). Our findings reveal a medium-high stability level in the QP, with minimal changes over recent years. The driving factors vary across landscape types, with climate and anthropogenic factors emerging as crucial determinants. While anthropogenic factors are strong but unstable due to policy changes and economic development, climatic factors exert a consistent influence. Based on our results, we propose site-specific ecological conservation and restoration measures. The ecological stability assessment framework provides a practical tool to understand the link between environmental conditions and ecosystems.
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Affiliation(s)
- Da Lü
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, Beijing, 100085, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yihe Lü
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, Beijing, 100085, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Guangyao Gao
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, Beijing, 100085, China
| | - Siqi Sun
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, Beijing, 100085, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yi Wang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, Beijing, 100085, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Bojie Fu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, Beijing, 100085, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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16
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Ding L, Li Z, Xu K, Huang M, Shen B, Hou L, Xiao L, Liang S, Shi Z, Wang X, Guo K, Yang Y, Xin X, Chang J. A water stress factor based on normalized difference water index substantially improved the accuracy of light use efficiency model for arid and semi-arid grasslands. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 349:119566. [PMID: 37976647 DOI: 10.1016/j.jenvman.2023.119566] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 10/01/2023] [Accepted: 11/04/2023] [Indexed: 11/19/2023]
Abstract
High-accuracy simulation of gross primary productivity (GPP) is crucial for the monitoring and evaluation of the ecosystem services and the adaptive management of grassland. The light use efficiency (LUE) model is one of the most widely-used methods to simulate GPP, given its simple structure and low input requirements. Current LUE models are less applicable to grasslands than other vegetation types and have lower overall estimation accuracy in arid and semi-arid regions. A grassland-specific light use efficiency model (GRASS-LUE), which optimizes three important parameters (the fraction of absorbed photosynthetically active radiation FPAR, optimum temperature Topt and water stress factor f(W)), has been developed to improve the accuracy of GPP simulation for grasslands along aridity gradients. GPP simulated by the GRASS-LUE agreed well with the eddy covariance (EC) GPP estimates for grasslands along the aridity gradient at 8-day (coefficient of determination (R2) = 0.85, Bias = -0.67 gC m-2 day-1), monthly (R2 = 0.88, Bias = -22.33 gC m-2 month-1) and annual time scales (R2 = 0.95, Bias = -118.91 gC m-2 year-1). Compared with five state-of-the-art GPP products (PML, MOD17, rEC-LUE, VPM and BESS), GRASS-LUE had the best and most stable performance in reproducing EC GPP, especially for semi-arid grassland, with the highest global performance indicator (GPI) value. Sensitivity tests further revealed that: 1) modifying f(W) to be based on the Normalized Difference Water Index (NDWI) substantially improved the model accuracy for arid and semi-arid grasslands and 2) using the minimum of temperature and water stress factors (i.e., min(f(W),f(T))) to represent environmental stress in GRASS-LUE was better than that from the multiplication of temperature and water stress factors (i.e., f(W)×f(T)).
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Affiliation(s)
- Lei Ding
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China; State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Zhenwang Li
- Jiangsu Key Laboratory of Crop Genetics and Physiology/ Jiangsu Key Laboratory of Crop Cultivation and Physiology, Agricultural College of Yangzhou University, Yangzhou 225009, China; Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Kang Xu
- School of Environmental Engineering, Wuxi University, Jiangsu, 214105, China
| | - Mengtian Huang
- Chinese Academy of Meteorological Science, Beijing, 100081, China
| | - Beibei Shen
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Lulu Hou
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Liujun Xiao
- National Engineering and Technology Center for Information Agriculture, Engineering Research Center of Smart Agriculture, Ministry of Education, Key Laboratory for Crop System Analysis and Decision Making, Ministry of Agriculture, Jiangsu Key Laboratory for Information Agriculture, Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China
| | - Shefang Liang
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Zhou Shi
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Xu Wang
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Kaiwen Guo
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Yuanyuan Yang
- The School of Spatial Planning & Design of Hangzhou City University, Hangzhou, 310015, China
| | - Xiaoping Xin
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Jinfeng Chang
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
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17
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Zhang L, Shen M, Yang Z, Wang Y, Chen J. Spatial variations in the difference in elevational shifts between greenness and temperature isolines across the Tibetan Plateau grasslands under warming. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167715. [PMID: 37820790 DOI: 10.1016/j.scitotenv.2023.167715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/26/2023] [Accepted: 10/08/2023] [Indexed: 10/13/2023]
Abstract
Climate warming has induced widespread isotherm shifts toward higher elevations on the Tibetan Plateau, but elevational shifts of vegetation greenness (indicated by Normalized Difference Vegetation Index, NDVI) do not necessarily keep pace with the isotherm shifts. Thus, there should be spatial variations in the difference between the velocities of vertical movement of greenness isolines (VNDVI) and isotherms (VT) across the Tibetan Plateau grasslands. Using satellite-observed NDVI and gridded climate data during 2000-2017, we found uphill shifts of the isotherms in 81.8 % of the surveyed areas, mainly in the eastern, central, southwestern, and northeastern parts, whereas upward shifts of the greenness isolines were observed only in 49.7 % of these areas, mainly in the southeastern, west-central, and southwestern edge of Tibetan Plateau grasslands. In the areas where both the greenness isolines and isotherms shifted uphill, VDNVI was faster than VT in the west-central and northeastern parts, and VNDVI was smaller than VT in the western, south-central, central, and southeastern regions; the difference between VNDVI and VT was positively related with elevational gradient of NDVI (NDVIEG) in the areas where NDVIEG was negative and the temporal trend of NDVI was positive, and was negatively related with NDVIEG and temporal trends of NDVI and temperature in the areas where NDVIEG was positive and temporal trend of NDVI was negative. Our results revealed spatial heterogeneity in the difference in the elevational shifts between the isotherm and vegetation greenness isoline across the Tibetan Plateau grasslands, which is related with both diverse adaptation to local environment (NDVIEG) and complex responses of vegetation greenness to warming in terms of both direction and magnitude. These findings have important implications for the prediction of vegetation production and carbon cycle and the adaptive management of alpine grasslands under climate change.
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Affiliation(s)
- Lei Zhang
- Institute of Tibetan Plateau Research, University of the Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Miaogen Shen
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China.
| | - Zhiyong Yang
- Institute of Tibetan Plateau Research, University of the Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China.
| | - Yafeng Wang
- Institute of Tibetan Plateau Research, University of the Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Jin Chen
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
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18
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Lin G, Hua L, Shen Y, Zhao Y. Change characteristics and influencing factors of grassland degradation in adjacent areas of the Qinghai-Tibet Plateau and suggestions for grassland restoration. PeerJ 2023; 11:e16084. [PMID: 37719111 PMCID: PMC10503501 DOI: 10.7717/peerj.16084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 08/21/2023] [Indexed: 09/19/2023] Open
Abstract
Natural grasslands are being progressively degraded around the world due to climate change and socioeconomic factors. Most of the drivers, processes, and consequences of grassland degradation are studied separately, and it is not yet clear whether the change characteristics and influence factors of adjacent areas of grassland are identical. We analyzed changes in grassland area and quality, and the influences of climate changes and socioeconomic factors from 1980-2018 in Maqu County, Xiahe County and Luqu County on the eastern Qinghai-Tibet Plateau (QTP). We found that areas with high and medium coverage grassland in Maqu County and Luqu County decreased continuously with time, while low coverage grassland areas increased in three counties. In Xiahe County, the medium coverage grassland area reduced with time (except for 2010), while the high and low coverage grassland areas increased. The actual net primary productivity of the three counties showed a downward trend. In Maqu County, the total grassland area had an extremely significant positive correlation with number of livestock going to market, commodity rate, gross domestic product (GDP), primary industry, tertiary industry, household density, and levels of junior middle school education and university education in the area. In Luqu County, the total grassland area high coverage grassland area were significantly negatively correlated with total number of livestock, secondary industry, levels of primary school education, and temperature. Ecological education was positively correlated with high coverage grassland, and negatively correlated with low coverage grassland in all three areas. The results of this study suggest that the best ways to restore the area and quality of grasslands in these areas would be to reduce the local cultivated land area and slow down the development of the primary and tertiary industries in Maqu County, and to control industry development and the total number of livestock in Luqu County. This study also suggests that improving education level and strengthening the level of ecological education are conducive to the restoration of grasslands.
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Affiliation(s)
- Gang Lin
- College of Pratacultural Science, Gansu Agricultural University, Lanzhou, No. 1 Yingmen Village, China
- Department of Gansu Natural Resources Planning and Research Institute, Lanzhou, China
| | - Limin Hua
- College of Pratacultural Science, Gansu Agricultural University, Lanzhou, No. 1 Yingmen Village, China
| | - Yanze Shen
- College of Pratacultural Science, Gansu Agricultural University, Lanzhou, No. 1 Yingmen Village, China
| | - Yajiao Zhao
- College of Pratacultural Science, Gansu Agricultural University, Lanzhou, No. 1 Yingmen Village, China
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Wang Z, Kang Y, Wang Y, Tan Y, Yao B, An K, Su J. Himalayan Marmot ( Marmota himalayana) Redistribution to High Latitudes under Climate Change. Animals (Basel) 2023; 13:2736. [PMID: 37684999 PMCID: PMC10486415 DOI: 10.3390/ani13172736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/23/2023] [Accepted: 08/25/2023] [Indexed: 09/10/2023] Open
Abstract
Climate warming and human activities impact the expansion and contraction of species distribution. The Himalayan marmot (Marmota himalayana) is a unique mammal and an ecosystem engineer in the Qinghai-Tibet Plateau (QTP). This pest aggravates grassland degradation and is a carrier and transmitter of plagues. Therefore, exploring the future distribution of Himalayan marmots based on climate change and human activities is crucial for ecosystem management, biodiversity conservation, and public health safety. Here, a maximum entropy model was explored to forecast changes in the distribution and centroid migration of the Himalayan marmot in the 2050s and 2070s. The results implied that the human footprint index (72.80%) and altitude (16.40%) were the crucial environmental factors affecting the potential distribution of Himalayan marmots, with moderately covered grassland being the preferred habitat of the Himalayan marmot. Over the next 30-50 years, the area of suitable habitat for the Himalayan marmot will increase slightly and the distribution center will shift towards higher latitudes in the northeastern part of the plateau. These results demonstrate the influence of climate change on Himalayan marmots and provide a theoretical reference for ecological management and plague monitoring.
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Affiliation(s)
- Zhicheng Wang
- College of Grassland Science, Gansu Agricultural University, Lanzhou 730070, China; (Z.W.); (K.A.)
- Key Laboratory of Grassland Ecosystem (Ministry of Education), Gansu Agricultural University, Lanzhou 730070, China
- Gansu Agricultural University-Massey University Research Centre for Grassland Biodiversity, Gansu Agricultural University, Lanzhou 730070, China
| | - Yukun Kang
- College of Grassland Science, Gansu Agricultural University, Lanzhou 730070, China; (Z.W.); (K.A.)
- Key Laboratory of Grassland Ecosystem (Ministry of Education), Gansu Agricultural University, Lanzhou 730070, China
- Gansu Agricultural University-Massey University Research Centre for Grassland Biodiversity, Gansu Agricultural University, Lanzhou 730070, China
| | - Yan Wang
- College of Grassland Science, Gansu Agricultural University, Lanzhou 730070, China; (Z.W.); (K.A.)
- Key Laboratory of Grassland Ecosystem (Ministry of Education), Gansu Agricultural University, Lanzhou 730070, China
- Gansu Agricultural University-Massey University Research Centre for Grassland Biodiversity, Gansu Agricultural University, Lanzhou 730070, China
| | - Yuchen Tan
- College of Grassland Science, Gansu Agricultural University, Lanzhou 730070, China; (Z.W.); (K.A.)
- Key Laboratory of Grassland Ecosystem (Ministry of Education), Gansu Agricultural University, Lanzhou 730070, China
- Gansu Agricultural University-Massey University Research Centre for Grassland Biodiversity, Gansu Agricultural University, Lanzhou 730070, China
| | - Baohui Yao
- College of Grassland Science, Gansu Agricultural University, Lanzhou 730070, China; (Z.W.); (K.A.)
- Key Laboratory of Grassland Ecosystem (Ministry of Education), Gansu Agricultural University, Lanzhou 730070, China
- Gansu Agricultural University-Massey University Research Centre for Grassland Biodiversity, Gansu Agricultural University, Lanzhou 730070, China
| | - Kang An
- College of Grassland Science, Gansu Agricultural University, Lanzhou 730070, China; (Z.W.); (K.A.)
- Key Laboratory of Grassland Ecosystem (Ministry of Education), Gansu Agricultural University, Lanzhou 730070, China
- Gansu Agricultural University-Massey University Research Centre for Grassland Biodiversity, Gansu Agricultural University, Lanzhou 730070, China
| | - Junhu Su
- College of Grassland Science, Gansu Agricultural University, Lanzhou 730070, China; (Z.W.); (K.A.)
- Key Laboratory of Grassland Ecosystem (Ministry of Education), Gansu Agricultural University, Lanzhou 730070, China
- Gansu Agricultural University-Massey University Research Centre for Grassland Biodiversity, Gansu Agricultural University, Lanzhou 730070, China
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Yang C, Zhang H, Zhao X, Liu P, Wang L, Wang W. A functional metagenomics study of soil carbon and nitrogen degradation networks and limiting factors on the Tibetan plateau. Front Microbiol 2023; 14:1170806. [PMID: 37228377 PMCID: PMC10203874 DOI: 10.3389/fmicb.2023.1170806] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 04/10/2023] [Indexed: 05/27/2023] Open
Abstract
Introduction The Three-River Source Nature Reserve is located in the core area of the Qinghai-Tibetan Plateau, with the alpine swamp, meadow and steppe as the main ecosystem types. However, the microbial communities in these alpine ecosystems, and their carbon and nitrogen degrading metabolic networks and limiting factors remain unclear. Methods We sequenced the diversity of bacteria and fungi in alpine swamps, meadows, steppes, and their degraded and artificially restored ecosystems and analyzed soil environmental conditions. Results The results indicated that moisture content had a greater influence on soil microbial community structure compared to degradation and restoration. Proteobacteria dominated in high moisture alpine swamps and alpine meadows, while Actinobacteria dominated in low moisture alpine steppes and artificial grasslands. A metabolic network analysis of carbon and nitrogen degradation and transformation using metagenomic sequencing revealed that plateau microorganisms lacked comprehensive and efficient enzyme systems to degrade organic carbon, nitrogen, and other biological macromolecules, so that the short-term degradation of alpine vegetation had no effect on the basic composition of soil microbial community. Correlation analysis found that nitrogen fixation was strong in meadows with high moisture content, and their key nitrogen-fixing enzymes were significantly related to Sphingomonas. Denitrification metabolism was enhanced in water-deficient habitats, and the key enzyme, nitrous oxide reductase, was significantly related to Phycicoccus and accelerated the loss of nitrogen. Furthermore, Bacillus contained a large number of amylases (GH13 and GH15) and proteases (S8, S11, S26, and M24) which may promote the efficient degradation of organic carbon and nitrogen in artificially restored grasslands. Discussion This study illustrated the irrecoverability of meadow degradation and offered fundamental information for altering microbial communities to restore alpine ecosystems.
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Affiliation(s)
- Chong Yang
- School of Geographical Sciences, Qinghai Normal University, Xining, China
- School of Life Sciences, Qinghai Normal University, Xining, China
| | - Hong Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Xinquan Zhao
- Northwest Plateau Institute of Biology, Chinese Academy of Sciences, Xining, China
| | - Pan Liu
- School of Geographical Sciences, Qinghai Normal University, Xining, China
| | - Lushan Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Wenying Wang
- School of Life Sciences, Qinghai Normal University, Xining, China
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Li Z, Qu H, Li L, Zheng J, Wei D, Wang F. Effects of climate change on vegetation dynamics of the Qinghai-Tibet Plateau, a causality analysis using empirical dynamic modeling. Heliyon 2023; 9:e16001. [PMID: 37206005 PMCID: PMC10189261 DOI: 10.1016/j.heliyon.2023.e16001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 04/27/2023] [Accepted: 04/28/2023] [Indexed: 05/21/2023] Open
Abstract
Given the vital role of the Qinghai-Tibet Plateau (QTP) as water tower in Asia and regulator for regional and even global climate, the relationship between climate change and vegetation dynamics on it has received considerable focused attention. Climate change may influence the vegetation growth on the plateau, but clear empirical evidence of such causal linkages is sparse. Herein, using datasets CRU-TS v4.04 and AVHHR NDVI from 1981 to 2019, we quantify causal effects of climate factors on vegetation dynamics with an empirical dynamical model (EDM) -- a nonlinear dynamical systems analysis approach based on state-space reconstruction rather than correlation. Results showed the following: (1) climate change promotes the growth of vegetation on the QTP, and specifically, this favorable influence of temperature is stronger than precipitation's; (2) the direction and strength of climate effects on vegetation varied over time, and the effects are seasonally different; (3) a significant increase in temperature and a slight increase in precipitation are beneficial to vegetation growth, specifically, NDVI will increase within 2% in the next 40 years with the climate trend of warming and humidity. Besides the above results, another interesting finding is that the two seasons in which precipitation strongly influence vegetation in the Three-River Source region (part of the QTP) are spring and winter. This study provides insights into the mechanisms by which climate change affects vegetation growth on the QTP, aiding in the modeling of vegetation dynamics in future scenarios.
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Affiliation(s)
- Zhaoni Li
- College of Computer Science and Technology, Chongqing University of Posts and Telecommunications, Chongqing, 400065, China
- College of Computer, Qinghai Normal University, Xining, 810008, China
- Institute of Ecological Safety Forewarning and Control, Chongqing University of Posts and Telecommunications, Chongqing, 400065, China
| | - Hongchun Qu
- College of Computer Science and Technology, Chongqing University of Posts and Telecommunications, Chongqing, 400065, China
- College of Automation, Chongqing University of Posts and Telecommunications, Chongqing, 400065, China
- Institute of Ecological Safety Forewarning and Control, Chongqing University of Posts and Telecommunications, Chongqing, 400065, China
- Corresponding author. College of Computer Science and Technology, Chongqing University of Posts and Telecommunications, Chongqing, 400065, China.
| | - Lin Li
- College of Computer Science and Technology, Chongqing University of Posts and Telecommunications, Chongqing, 400065, China
| | - Jian Zheng
- College of Computer Science and Technology, Chongqing University of Posts and Telecommunications, Chongqing, 400065, China
| | - Dianwen Wei
- Institute of Natural Resources and Ecology, Heilongjiang Academy of Sciences, Harbin, 150040, China
| | - Fude Wang
- Institute of Forestry Science of Heilongjiang Province, Harbin, 150081, China
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22
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Shi F, Liu S, An Y, Sun Y, Zhao S, Liu Y, Li M. Climatic factors and human disturbance influence ungulate species distribution on the Qinghai-Tibet Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 869:161681. [PMID: 36682551 DOI: 10.1016/j.scitotenv.2023.161681] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 12/12/2022] [Accepted: 01/14/2023] [Indexed: 06/17/2023]
Abstract
Due to human activities and climate change, the habitats of ungulate species on the Qinghai-Tibet Plateau have been greatly affected in recent decades. In this study, the distribution patterns of 19 ungulate species on the Qinghai-Tibet Plateau were identified based on MaxEnt model in the past (1960-1990) and current periods (2000-2015). Then the changes of their habitat distribution and the species richness in different periods were compared. Finally, the Zonation model was used to identify the key protected areas of ungulate species. The results show that the MaxEnt model can well predict the distribution of ungulate species. Most ungulate species are mainly distributed in the southeast of the Qinghai-Tibet Plateau. The distance to lakes and precipitation are the main factors affecting the distribution of most ungulate species. The habitats originally located in the southeast of the Qinghai-Tibet Plateau have mainly extended northeastwards, while the habitats originally located in the northwest has been largely lost. The changes in the habitats of ungulate species in the southeast and northwest are diametrically opposite. The key protected areas identified by Zonation model are mainly located in the southeast of the Qinghai-Tibet Plateau. The existing nature reserves can effectively protect the suitable habitats of the Tibetan antelope, Tibetan wild ass and wild yak. This research can provide scientific basis for coordinating the contradiction between development and protection and promoting the biodiversity conservation on the Qinghai-Tibet Plateau.
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Affiliation(s)
- Fangning Shi
- School of Environment and Resources, Taiyuan University of Science and Technology, Taiyuan, China
| | - Shiliang Liu
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, China.
| | - Yi An
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, China
| | - Yongxiu Sun
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, China
| | - Shuang Zhao
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, China
| | - Yixuan Liu
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, China
| | - Mingqi Li
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, China
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23
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He S, Xiong K, Song S, Chi Y, Fang J, He C. Research Progress of Grassland Ecosystem Structure and Stability and Inspiration for Improving Its Service Capacity in the Karst Desertification Control. PLANTS (BASEL, SWITZERLAND) 2023; 12:770. [PMID: 36840118 PMCID: PMC9959505 DOI: 10.3390/plants12040770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/04/2023] [Accepted: 02/05/2023] [Indexed: 06/18/2023]
Abstract
The structure and stability of grassland ecosystems have a significant impact on biodiversity, material cycling and productivity for ecosystem services. However, the issue of the structure and stability of grassland ecosystems has not been systematically reviewed. Based on the Web of Science (WOS) and China National Knowledge Infrastructure (CNKI) databases, we used the systematic-review method and screened 133 papers to describe and analyze the frontiers of research into the structure and stability of grassland ecosystems. The research results showed that: (1) The number of articles about the structure and stability of grassland ecosystems is gradually increasing, and the research themes are becoming increasingly diverse. (2) There is a high degree of consistency between the study area and the spatial distribution of grassland. (3) Based on the changes in ecosystem patterns and their interrelationships with ecosystem processes, we reviewed the research progress and landmark results on the structure, stability, structure-stability relationship and their influencing factors of grassland ecosystems; among them, the study of structure is the main research focus (51.12%), followed by the study of the influencing factors of structure and stability (37.57%). (4) Key scientific questions on structural optimization, stability enhancement and harmonizing the relationship between structure and stability are explored. (5) Based on the background of karst desertification control (KDC) and its geographical characteristics, three insights are proposed to optimize the spatial allocation, enhance the stability of grassland for rocky desertification control and coordinate the regulation mechanism of grassland structure and stability. This study provided some references for grassland managers and relevant policy makers to optimize the structure and enhance the stability of grassland ecosystems. It also provided important insights to enhance the service capacity of grassland ecosystems in KDC.
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Affiliation(s)
- Shuyu He
- School of Karst Science, Guizhou Normal University, Guiyang 550001, China
- State Engineering Technology Institute for Karst Desertification Control of China, 116 Baoshan North Road, Guiyang 550001, China
| | - Kangning Xiong
- School of Karst Science, Guizhou Normal University, Guiyang 550001, China
- State Engineering Technology Institute for Karst Desertification Control of China, 116 Baoshan North Road, Guiyang 550001, China
| | - Shuzhen Song
- School of Karst Science, Guizhou Normal University, Guiyang 550001, China
- State Engineering Technology Institute for Karst Desertification Control of China, 116 Baoshan North Road, Guiyang 550001, China
| | - Yongkuan Chi
- School of Karst Science, Guizhou Normal University, Guiyang 550001, China
- State Engineering Technology Institute for Karst Desertification Control of China, 116 Baoshan North Road, Guiyang 550001, China
| | - Jinzhong Fang
- School of Karst Science, Guizhou Normal University, Guiyang 550001, China
- State Engineering Technology Institute for Karst Desertification Control of China, 116 Baoshan North Road, Guiyang 550001, China
| | - Chen He
- School of Karst Science, Guizhou Normal University, Guiyang 550001, China
- State Engineering Technology Institute for Karst Desertification Control of China, 116 Baoshan North Road, Guiyang 550001, China
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24
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Ma B, Jing J, Liu B, Wang Y, He H. Assessing the contribution of human activities and climate change to the dynamics of NPP in ecologically fragile regions. Glob Ecol Conserv 2023. [DOI: 10.1016/j.gecco.2023.e02393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
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25
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Li Q, Qiu J, Liang Y, Lan G. Soil bacterial community changes along elevation gradients in karst graben basin of Yunnan-Kweichow Plateau. Front Microbiol 2022; 13:1054667. [PMID: 36620048 PMCID: PMC9813600 DOI: 10.3389/fmicb.2022.1054667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 12/02/2022] [Indexed: 12/24/2022] Open
Abstract
Elevation gradients could provide natural experiments to examine geomorphological influences on biota ecology and evolution, however little is known about microbial community structures with soil depths along altitudinal gradients in karst graben basin of Yunnan-Kweichow Plateau. Here, bulk soil in A layer (0 ~ 10 cm) and B layer (10 ~ 20 cm) from two transect Mounts were analyzed by using high-throughput sequencing coupled with physicochemical analysis. It was found that the top five phyla in A layer were Proteobacteria, Acidobacteria, Actinobacteria, Bacteroidetes, and Verrucomicrobia, and the top five phyla in B layer were Proteobacteria, Acidobacteria, Actinobacteria, Verrucomicrobia, and Chloroflexi in a near-neutral environment. Edaphic parameters were different in two layers along altitudinal gradients. Besides that, soil microbial community compositions varied along altitudinal gradient, and soil organic carbon (SOC) and total nitrogen (TN) increased monotonically with increasing elevation. It was further observed that Shannon indexes with increasing altitudes in two transect Mounts decreased monotonically with significant difference (p = 0.001), however beta diversity followed U-trend with significant difference (p = 0.001). The low proportions of unique operational taxonomic units (OTUs) appeared at high altitude areas which impact the widely accepted elevation Rapoport's rules. The dominant Bradyrhizobium (alphaproteobacterial OTU 1) identified at high altitudes in two layers constitutes the important group of free-living diazotrophs and could bring fixed N into soils, which simultaneously enhances SOC and TN accumulation at high altitudes (p < 0.01). Due to different responses of bacterial community to environmental changes varying with soil depths, altitudinal gradients exerted negative effects on soil bacterial communities via soil physical properties and positive effects on soil bacterial diversities via soil chemical properties in A layer, however the results in B layer were opposite. Overall, our study is the first attempt to bring a deeper understanding of soil microbial structure patterns along altitudinal gradients at karst graben basin areas.
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Affiliation(s)
- Qiang Li
- Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification, MNR, Key Laboratory of Karst Dynamics, MNR & GZAR, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, China,International Research Center on Karst under the Auspices of UNESCO, Guilin, China,*Correspondence: Qiang Li, ✉
| | - Jiangmei Qiu
- Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification, MNR, Key Laboratory of Karst Dynamics, MNR & GZAR, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, China,International Research Center on Karst under the Auspices of UNESCO, Guilin, China
| | - Yueming Liang
- Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification, MNR, Key Laboratory of Karst Dynamics, MNR & GZAR, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, China,International Research Center on Karst under the Auspices of UNESCO, Guilin, China
| | - Gaoyong Lan
- Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification, MNR, Key Laboratory of Karst Dynamics, MNR & GZAR, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, China,International Research Center on Karst under the Auspices of UNESCO, Guilin, China
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26
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Determining whether Qinghai-Tibet Plateau waterbodies have acted like carbon sinks or sources over the past 20 years. Sci Bull (Beijing) 2022; 67:2345-2357. [PMID: 36546224 DOI: 10.1016/j.scib.2022.10.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 10/23/2022] [Accepted: 10/24/2022] [Indexed: 11/11/2022]
Abstract
Half of all of China's lakes are on the Qinghai-Tibet Plateau (QTP), which are mainly distributed at altitudes above 4000 m asl. Being under conditions of progressively intensifying anthropogenic activities and climate change, the debate on whether QTP lakes act as carbon (C) sinks or sources remains unresolved. This study explores QTP lake C exchange processes and characteristics over the past two decades through field monitoring and data integration. Results reveal high lake carbon dioxide (CO2) exchange flux distribution patterns in its western and southern regions and correspondingly low values in its eastern and northern regions. Lake CO2 exchange flux rates also show significant temporal differences where those in the 2000s and 2010s were significantly higher compared to the 2020s. Annual total CO2 emission flux from QTP lakes has increased from 1.60 Tg C a-1 in the 2000s to 6.87 Tg C a-1 in the 2010s before decreasing to 1.16 Tg C a-1 in the 2020s. However, QTP lakes have generally acted as C sinks when annual ice-cover periods are included in the estimation of annual C budgets. Consequently, QTP lakes are gradually evolving towards C sinks. Some small-sized freshwater lakes on the QTP exhibit C sequestration characteristics while low-mid altitude saltwater lakes also act as C sinks. Therefore, owing to the high uncertainties in the estimation of C exchange flux, the QTP lake C sink capacity has been largely underestimated.
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27
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Wang N, Zhang Z, Xu W, Zhou H, Ning R. Research Progress on Dormancy Mechanism and Germination Technology of Kobresia Seeds. PLANTS (BASEL, SWITZERLAND) 2022; 11:3192. [PMID: 36501232 PMCID: PMC9736853 DOI: 10.3390/plants11233192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/16/2022] [Accepted: 11/20/2022] [Indexed: 06/17/2023]
Abstract
Kobresia is a subfamily of Cyperaceae, a perennial herbaceous plant that stores a large amount of organic carbon and nutrients (nitrogen, phosphorus, etc.) in the soil. This type of grass is soft and appreciated by all kinds of farm animals. It is one of the predominantly excellent fodder on the Qinghai-Tibet Plateau. Its good growth plays an important role in developing the local economy and maintaining ecological balance on the Qinghai-Tibet Plateau as well. The main objectives of this review are to systematically present and analyze the factors responsible for the low germination rate of Kobresia and to analyze the physical and chemical methods that are used in order to alleviate dormancy and to improve the germination rate of Kobresia seeds. This is performed in order to lay the foundation for future research in this field. At the same time, we have analyzed the research deficiencies and formulated recommendations for the future. This review will provide comprehensive information in order to reduce the cost of planting Kobresia, as well as to provide theoretical support and technical guidance for the purposes of ecosystem restoration and livestock development.
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Affiliation(s)
- Na Wang
- Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810001, China
- Key Laboratory of the Cold Regions Restoration Ecology, Xining 810001, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhonghua Zhang
- Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810001, China
- Key Laboratory of the Cold Regions Restoration Ecology, Xining 810001, China
| | - Wenhua Xu
- Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810001, China
- Key Laboratory of the Cold Regions Restoration Ecology, Xining 810001, China
| | - Huakun Zhou
- Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810001, China
- Key Laboratory of the Cold Regions Restoration Ecology, Xining 810001, China
| | - Rongchun Ning
- Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810001, China
- Key Laboratory of the Cold Regions Restoration Ecology, Xining 810001, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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Dong B, Yu Y, Pereira P. Non-growing season drought legacy effects on vegetation growth in southwestern China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 846:157334. [PMID: 35842151 DOI: 10.1016/j.scitotenv.2022.157334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 07/03/2022] [Accepted: 07/09/2022] [Indexed: 06/15/2023]
Abstract
Water availability influences terrestrial ecosystems' composition, structure, and function. Recently, climate change increased drought periods frequency and length in many parts of the world, including southwestern China, a biodiversity hotspot. Although the drought impacts on ecosystems are well known, studies are scarce in subtropical areas of China. This work studied the drought legacy effects on vegetation growth in southwestern China using Normalized Difference Vegetation Index (NDVI) and the Standardized Precipitation Evapotranspiration Index (SPEI), with a particular focus on non-growing season extreme drought events. Pervasive non-growing season drought legacy effects were found in the first growing season in most parts of southwestern China. The highest impacts were identified in forests, while the effects in grass were less severe. At the regional scale, horizontal and vertical spatial patterns of drought legacy effects were heterogeneous, and the highest impacts were found in warmer and wetter forests and alpine grasslands. Our study highlights that severe drought conditions may dramatically affect vegetation growth in southwestern China.
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Affiliation(s)
- Bogang Dong
- School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
| | - Yang Yu
- School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China; Jixian National Forest Ecosystem Observation and Research Station, CNERN, School of Soil and Water Conservation, Beijing Forestry University, China.
| | - Paulo Pereira
- Environmental Management Center, Mykolas Romeris University, Ateities g. 20, LT-08303 Vilnius, Lithuania
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Zhang L, Li Q, Kou X, Ouyang Z. Distributions of two native ungulates at the third pole are highly sensitive to global warming. Glob Ecol Conserv 2022. [DOI: 10.1016/j.gecco.2022.e02292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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30
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Wang Q, Ju Q, Wang Y, Shao Q, Zhang R, Liu Y, Hao Z. Vegetation Changing Patterns and Its Sensitivity to Climate Variability across Seven Major Watersheds in China. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:13916. [PMID: 36360794 PMCID: PMC9657582 DOI: 10.3390/ijerph192113916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 10/06/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
Climate changes have profound impacts on vegetation and further alter hydrological processes through transpiration, interception, and evaporation. This study investigated vegetation's changing patterns and its sensitivity to climate variability across seven major watersheds in China based on a hybrid regionalization approach and a novel, empirical index-Vegetation Sensitivity Index (VSI). Vegetation showed linearly increasing trends in most of the seven watersheds, while decreases in vegetation were mostly found in the source regions of the Yangtze River Basin (YZRB) and Yellow River Basin (YRB), the forest and grassland areas of the Songhua River Basin (SHRB) and Liao River Basin (LRB), the Yangtze River Delta, and the Pearl River Delta during the growing season. The selected watersheds can be categorized into 11 sub-regions, and the regionalization result was consistent with the topography and vegetation types; the characteristics of vegetation dynamics were more homogeneous among sub-regions. Vegetation types such as forests and shrubland in the central parts of the YZRB were relatively more vulnerable to climate variations than the grasslands and alpine meadows and tundra (AMT) in the source regions of the YZRB and YRB and the Loess Plateau of the YRB. In arid and semi-arid regions, precipitation had a profound impact on vegetation, while, at low latitudes, solar radiation was the main controlling factor. Such comprehensive investigations of the vegetation-climate relationship patterns across various watersheds are expected to provide a foundation for the exploration of future climate change impacts on ecosystems at the watershed scale.
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Affiliation(s)
- Qin Wang
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China
| | - Qin Ju
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China
| | - Yueyang Wang
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China
| | - Quanxi Shao
- CSIRO Data 61, Australian Resources Research Centre, Kensington, WA 6151, Australia
| | - Rongrong Zhang
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China
| | - Yanli Liu
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing 210029, China
| | - Zhenchun Hao
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China
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Analyzing the Spatiotemporal Vegetation Dynamics and Their Responses to Climate Change along the Ya’an–Linzhi Section of the Sichuan–Tibet Railway. REMOTE SENSING 2022. [DOI: 10.3390/rs14153584] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Vegetation dynamics and their responses to climate change are of significant spatial and temporal heterogeneity. The Sichuan–Tibet Railway (STR) is a major construction project of the 14th Five-Year Plan for Economic and Social Development of the People’s Republic of China that is of great significance to promoting the social and economic development of Sichuan–Tibet areas. The planned railway line crosses areas with a complex geological condition and fragile ecological environment, where the regional vegetation dynamics are sensitive to climate change, topographic conditions and human activities. So, analyzing the vegetation variations in the complex vertical ecosystem and exploring their responses to hydrothermal factors are critical for providing technical support for the ecological program’s implementation along the route of the planned railway line. Based on MOD13Q1 Normalized Difference Vegetation Index (NDVI) data for the growing season (May to October) during 2001–2020, a Theil-Sen trend analysis, Mann–Kendall test, Hurst exponent analysis and partial correlation analysis were used to detect the vegetation dynamics, predict the vegetation sustainability, examine the relationship between vegetation change and hydrothermal factors, regionalize the driving forces for vegetation growth and explore the interannual variation pattern of driving factors. The growing season NDVI along the Ya’an–Linzhi section of the STR showed a marked rate of increase (0.0009/year) during the past 20 years, and the vegetation’s slight improvement areas accounted for the largest proportion (47.53%). Among the three hydrothermal parameters (temperature, precipitation and radiation), the correlation between vegetation growth and the temperature was the most significant, and the vegetation response to precipitation was the most immediate. The vegetation changes were affected by the combined impact of climatic and non-climatic factors, and the proportion of hydrothermal factors’ combined driving force slightly increased during the study period. Based on the Hurst exponent, the future vegetation sustainability of the area along the Ya’an–Linzhi section of the STR faces a risk of degradation, and more effective conservations should be implemented during the railway construction period to protect the regional ecological environment.
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Liu Y, Lu H, Tian P, Qiu L. Evaluating the effects of dams and meteorological variables on riparian vegetation NDVI in the Tibetan Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 831:154933. [PMID: 35367542 DOI: 10.1016/j.scitotenv.2022.154933] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 02/24/2022] [Accepted: 03/27/2022] [Indexed: 06/14/2023]
Abstract
As the third pole of the world, the Qinghai-Tibet Plateau (QTP) has a very special climate and geographical environment. In the past 20 years, with the increasing demand for clean energy, more than ten hydropower stations have been built. The impacts of these hydropower stations on riparian vegetation (RV) have only been described qualitatively in previous studies, while the contribution of dams and meteorological variables to riparian vegetation has not been quantitatively assessed. This study selected eight representative large-scale hydropower stations in the QTP, calculated and analyzed the dynamics of the standardized difference vegetation index (NDVI) of the RV pre-and post the dams construction, combined with the measured temperature and precipitation data to explore the driving factors of RV changes. The results show that the dams promoted the growth of RV and they were the main contributor (>50%) while precipitation and temperature had relatively small impacts. The effect of dams varies for different regions, compared with the sub-cold regions, it was more significant in humid and semi-humid regions of temperate zone. The dams affected RV in an indirect way through regulating the microclimate, promoting precipitation and slowing down the rate of temperature rise and these effects may come from the increase of the upstream water surface area.
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Affiliation(s)
- Yunlong Liu
- State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300072, China
| | - Hongwei Lu
- Key Laboratory of Water Cycle and Related Land Surface Process, Institute of Geographic Science and Natural Resources Research, Chinese Academy of Science, Beijing 100101, China.
| | - Peipei Tian
- Institute of Blue and Green Development, Shandong University, Weihai 264209, China
| | - Lihua Qiu
- School of new energy, North China Electric Power University, Beijing 100101, China
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33
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Distinguishing the Impacts of Human Activities and Climate Change on the Livelihood Environment of Pastoralists in the Qinghai Lake Basin. SUSTAINABILITY 2022. [DOI: 10.3390/su14148402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Grassland vegetation is the largest terrestrial ecosystem in the Qinghai Lake Basin (QLB), and it is also the most important means of production for herders’ livelihoods. Quantifying the impact of climate change and human activities on grassland vegetation changes is an essential task for ensuring the sustainable livelihood of pastoralists. To this end, we investigated vegetation cover changes in the QLB from 2000 to 2020 using the normalized difference vegetation index (NDVI), meteorological raster data, and digital elevation and used residual analysis of multiple linear regression to evaluate the residuals of human activities. The residual analysis of partial derivatives was used to quantify the contribution of climate change and human activities to changes in vegetation cover. The results showed that: (1) The vegetation coverage of the QLB increased significantly (0.002/a, p < 0.01), with 91.38% of the area showing a greening trend, and 8.62% of the area suffering a degrading trend. The NDVI decreased substantially along the altitude gradient (−0.02/a, p < 0.01), with the highest vegetation coverage at 3600–3700 m (0.37/a). The vegetation degraded from 3200–3300 m, vegetation greening accelerated from 3300–3500 m, and vegetation greening slowed above 3500 m. (2) The contribution of climate change, temperature (T), and precipitation (P) to vegetation cover change were 1.62/a, 0.005/a, and 1.615/a, respectively. Below 3500 m, the vegetation greening was more limited by P. Above 3500 m, the vegetation greening was mainly limited by T. (3) Residual analysis showed that the contribution of human activities to vegetation cover was −1.618/a. Regarding the altitude gradient, at 3300–3500 m, human activities had the highest negative contribution to vegetation coverage (−2.389/a), and at 3200–3300 m, they had the highest positive contribution (0.389/a). In the past 21 years, the impact of human activities on vegetation coverage changed from negative to positive. Before 2009, the annual average NDVIres value was negative; after 2010, the average yearly NDVIres value turned positive. In general, the vegetation greening of the QLB depends on climate warming and humidification. The positive impact of human activities over the past decade was also essential for vegetation greening. These findings deepen our understanding of the QLB vegetation changes under climate change and human activities.
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Divergent Climate Sensitivities of the Alpine Grasslands to Early Growing Season Precipitation on the Tibetan Plateau. REMOTE SENSING 2022. [DOI: 10.3390/rs14102484] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Warming is expected to intensify hydrological processes and reshape precipitation regimes, which is closely related to water availability for terrestrial ecosystems. Effects of the inter-annual precipitation changes on plant growth are widely concerned. However, it is not well-known how plant growth responds to intra-annual precipitation regime changes. Here, we compiled reanalysis climate data (ERA5) and four satellite-based vegetation indices, including the Normalized Difference Vegetation Index (NDVI), the Enhanced Vegetation Index (EVI), the Solar-induced Chlorophyll Fluorescence (SIF), and the Modified Triangular Vegetation Index (MTVI2), to evaluate the response of alpine grasslands (including alpine meadow and alpine steppe) to the change of precipitation regimes, especially to the intra-annual precipitation regimes on the Tibetan Plateau. We found monthly precipitation over the alpine steppe significantly increased in the growing season (May–September), but precipitation over the alpine meadow significantly increased only in the early growing season (May–June) (MJP) during the past four decades (1979–2019). The inter-annual plant growth (vegetation indices changes) on the alpine meadow was dominated by temperature, but it was driven by precipitation for the alpine steppe. On the intra-annual scale, the temperature sensitivity of the vegetation indices generally decreased but precipitation sensitivity increased during the growing season for both the alpine meadow and steppe. In response to the increase in MJP, we found the temperature sensitivity of the vegetation indices during the mid-growing season (July–August) (MGNDVI, MGEVI, MGSIF, and MGMTVI2) in the alpine meadow significantly increased (p < 0.01) while its precipitation sensitivity significantly decreased (p < 0.01). We infer that more MJP over the meadow may be the result of enhanced evapotranspiration, which is at the expense of soil moisture and even induces soil “drought” in the early growing season. This may be to elevate community water acquisition capacity through altering root mass allocation and community composition, consequently regulating the divergent climate sensitivities of vegetation growth in the mid-growing season. Our findings highlight that it is inadequate to regard precipitation as an indicator of water availability conditions for plant growth, which may limit our understanding of the response and acclimatization of plants to climate change.
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35
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Zhang Z, Lu C. Assessing influences of climate change on highland barley productivity in the Qinghai-Tibet Plateau during 1978-2017. Sci Rep 2022; 12:7625. [PMID: 35538148 PMCID: PMC9090838 DOI: 10.1038/s41598-022-11711-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 04/18/2022] [Indexed: 11/28/2022] Open
Abstract
Grain production is becoming increasingly vulnerable to climate change globally. Highland barley (HB) is the most important cereal crop in the Qinghai-Tibet Plateau (QTP), so assessing HB productivity and its response to climate change could help to understand the capacity of grain production and food security. This study simulated the potential yield of HB annually at 72 meteorological stations for 1978–2017 using the WOFOST model, and then analyzed the spatiotemporal changes of HB potential yield and climatic factors in the growing season. Further, the influence of climate change on HB potential yield was explored in different temperature zones (TZ). Results indicate that the annual average of HB potential yield ranged from 3.5 to 8.1 t/ha in the QTP, and it was averaged at 6.5 t/ha in TZ-3, higher than other zones. From 1978 to 2017, HB potential yield for the whole QTP decreased slightly by 2.1 kg/ha per year, and its change rates were 23.9, 10.1, − 15.9, − 23.8 and − 16.7 kg/ha/year from TZ-1 to TZ-5 (p < 0.05), respectively. In all zones, average (Tave), maximum (Tmax) and minimum temperature (Tmin) showed a significantly warming trend (p < 0.01), and Tmin increased by 0.53, 0.45, 0.44, 0.40 and 0.69 °C per decade, higher than that of Tave and Tmax. However, temperature diurnal range (TDR) and radiation (RA) showed a downward trend, and their decrease rates were far higher in TZ-5 and TZ-3. In TZ-1, ΔTDR was the critical factor to the change in HB potential yield, which would increase by 420.30 kg/ha for 1 °C increase of ΔTDR (p < 0.01). From TZ-2 to TZ-5, ΔRA was the critical factor, but the influence amplitude in terms of the elastic coefficient, decreased from 4.08 to 0.99 (p < 0.01). In addition, other factors such as ΔTmax in TZ-3 and ΔTmin in TZ-4 and TZ-5 also had an important influence on the potential yield. To improve the HB productivity in the QTP, suitable varieties should be developed and introduced to adapt the climate warming in different temperature zones. In addition, efforts are needed to adjust the strategies of fertilizers and irrigation applications.
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Affiliation(s)
- Zemin Zhang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Changhe Lu
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China. .,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China.
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36
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Wang G, Peng W. Quantifying spatiotemporal dynamics of vegetation and its differentiation mechanism based on geographical detector. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:32016-32031. [PMID: 35015237 DOI: 10.1007/s11356-021-17544-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 11/11/2021] [Indexed: 06/14/2023]
Abstract
The influence of factors on vegetation changes in different regions is still largely unknown. We applied the geographic detector, a new spatial statistical method, to study the interactive effects of factors on the spatial patterns of normalised vegetation index (NDVI) changes and determine the optimal characteristics of key impact factors beneficial to vegetation growth. Our results show that from 2000 to 2015, the vegetation cover for the upper reaches of the Minjiang River, western China was in good condition. Furthermore, more than 80% of the areas had NDVI values ranging from 0.6 to 0.8 and NDVI > 0.8, and the spatial-temporal changes of vegetation cover were significant. The vegetation cover changes showed a significant transformation in the regions with NDVI > 0.6. Our study uniquely illustrated that elevation, annual average temperature and soil type can explain vegetation changes quite well. We propose that interactive effects exist among impact factors on vegetation NDVI, and the synergistic effects of the impact factors show mutual and nonlinear enhancements. The interactions among impact factors significantly enhance the impact of a single factor on vegetation changes. The most suitable characteristics of the main impact factors that promote vegetation growth were revealed by this study and will help improve our understanding of factors that impact NDVI and its driving mechanisms. Our findings suggest that the established favourable value range or the most suitable characteristics of impact factors will help management plans to intervene and promote vegetation change for vegetation restoration and alleviate environmental degradation.
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Affiliation(s)
- Guangjie Wang
- The Institute of Geography and Resources Science, Sichuan Normal University, Chengdu, 610068, People's Republic of China
- Key Lab of Land Resources Evaluation and Monitoring in Southwest, Ministry of Education, Sichuan Normal University, Chengdu, 610068, People's Republic of China
| | - Wenfu Peng
- The Institute of Geography and Resources Science, Sichuan Normal University, Chengdu, 610068, People's Republic of China.
- Key Lab of Land Resources Evaluation and Monitoring in Southwest, Ministry of Education, Sichuan Normal University, Chengdu, 610068, People's Republic of China.
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37
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Seasonal Variation of Vegetation and Its Spatiotemporal Response to Climatic Factors in the Qilian Mountains, China. SUSTAINABILITY 2022. [DOI: 10.3390/su14094926] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The purpose of this study is to reveal the seasonal difference in vegetation variation and its seasonal response to climate factors in the Qilian Mountains (QM) under the background of global warming. Based on the MOD13 A2 normalized difference vegetation index (NDVI) data and meteorological data, this study analyzed the spatiotemporal dynamics and stability of vegetation in different seasons by using the mean value method, trend analysis and stability analysis method, and discussed their seasonal responses to climatic factors based on the correlation analysis method. The results show that the vegetation cover in the QM experienced a significant upward trend in the past 21 years, but there were obvious spatial differences in vegetation change in different seasons. The growth rate of vegetation in summer was the fastest, and summer vegetation provided the most significant contribution to the growing season vegetation. The order of vegetation stability in the QM among the seasons was growing season > summer > spring > autumn. The vegetation change was obviously affected by temperature in spring, while it was mainly controlled by precipitation in the growing season and summer. The response of vegetation to climatic factors was not significant in autumn. Our results can provide important data support for ecological protection in the QM and socioeconomic development in the Hexi Corridor.
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38
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Li C, Liao H, Xu L, Wang C, He N, Wang J, Li X. The adjustment of life history strategies drives the ecological adaptations of soil microbiota to aridity. Mol Ecol 2022; 31:2920-2934. [PMID: 35344623 DOI: 10.1111/mec.16445] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 03/01/2022] [Accepted: 03/16/2022] [Indexed: 11/30/2022]
Abstract
Soil microbiota increase their fitness to local habitats by adjusting their life history strategies. Yet, how such adjustments drive their ecological adaptations in xeric grasslands remains elusive. In this study, shifts in the traits that potentially represent microbial life history strategies were studied along two aridity gradients with different climates using metagenomic and trait-based approaches. The results indicated that resource acquisition (e.g., higher activities of β-D-glucosidase and N-acetyl-beta-D-glucosidase, higher degradation rates of cellulose and chitin as well as genes involved in cell motilities, biodegradations, transportations and competitions) and growth yield (e.g., higher biomass and respiration) strategies were depleted with a higher aridity. However, cellular and high growth potential maintenance (e.g., higher metabolic quotients and genes related to DNA replication, transcription, translation, central carbon metabolisms and biosynthesis) and stress tolerance (e.g., genes involved in DNA damage repair, cation transporter, sporulation and osmolyte biosynthesis) strategies were enriched with a higher aridity. This implied that microbiota have lower growth yields but are probably well primed for rapid responses to pulse rainfalls in more arid soils, whereas those in less arid soils may have stronger resource acquisition and growth yield abilities. By integrating a large amount of evidence involved in taxonomic, metagenomic, genomic and biochemical properties, this study demonstrated that the ecological adaptations of soil microbiota to aridity made by adjusting and optimizing their life history strategies are universal in xeric grasslands and provided an underlying mechanistic understanding of soil microbial responses to climate changes.
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Affiliation(s)
- Chaonan Li
- Key Laboratory of Environmental and Applied Microbiology, Chinese Academy of Sciences, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China
| | - Haijun Liao
- Key Laboratory of Environmental and Applied Microbiology, Chinese Academy of Sciences, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China
| | - Lin Xu
- Key Laboratory of Environmental and Applied Microbiology, Chinese Academy of Sciences, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China
| | - Changting Wang
- Institute of Qinghai-Tibet Plateau, Southwest Minzu University, Chengdu, 610041, China
| | - Nianpeng He
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Junming Wang
- Section of Climate Science, Illinois State Water Survey, Prairie Research Institute, University of Illinois at Urbana-Champaign, Champaign, IL, 61802, USA
| | - Xiangzhen Li
- Key Laboratory of Environmental and Applied Microbiology, Chinese Academy of Sciences, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China
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39
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Driving Climatic Factors at Critical Plant Developmental Stages for Qinghai–Tibet Plateau Alpine Grassland Productivity. REMOTE SENSING 2022. [DOI: 10.3390/rs14071564] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Determining the driving climatic factors at critical periods and potential legacy effects is crucial for grassland productivity predictions on the Qinghai–Tibet Plateau (QTP). However, studies with limited and ex situ ground samples from highly heterogeneous alpine meadows brought great uncertainties. This study determined the key climatic factors at critical plant developmental stages and the impact of previous plant growth status for interannual aboveground net primary productivity (ANPP) variations in different QTP grassland types. We hypothesize that the impact of climatic factors on grassland productivity varies in different periods and different vegetation types, while its legacy effects are not great. Pixel-based partial least squares regression was used to associate interannual ANPP with precipitation and air temperature at different developmental stages and prior-year ANPP from 2000 to 2019 using remote sensing techniques. Results indicated different findings from previous studies. Precipitation at the reproductive stage (July–August) was the most prominent controlling factor for ANPP which was also significantly affected by precipitation and temperature at the withering (September–October) and dormant stage (November–February), respectively. The influence of precipitation was more significant in alpine meadows than in alpine steppes, while the differentiated responses to climatic factors were attributed to differences in water consumption at different developmental stages induced by leaf area changes, bud sprouting, growth, and protection from frost damage. The prior-year ANPP showed a non-significant impact on ANPP of current year, except for alpine steppes, and this impact was much less than that of current-year climatic factors, which may be attributed to the reduced annual ANPP variations related to the inter-annual carbon circulation of alpine perennial herbaceous plants and diverse root/shoot ratios in different vegetation types. These findings can assist in improving the interannual ANPP predictions on the QTP under global climate change.
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40
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Zhang L, Zhang H, Xu E. Information entropy and elasticity analysis of the land use structure change influencing eco-environmental quality in Qinghai-Tibet Plateau from 1990 to 2015. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:18348-18364. [PMID: 35022979 DOI: 10.1007/s11356-021-17978-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 12/02/2021] [Indexed: 06/14/2023]
Abstract
Regional land use change affects eco-environmental quality by altering ecosystem structure and function. The primitive ecosystem and environment of the Qinghai-Tibet Plateau (QTP) occupies a special position in the world, but it is very fragile. Although land use activities on the plateau have increased gradually in past decades, its effects on eco-environmental quality and the underlying mechanisms of regional heterogeneity remain unclear. In this study, an eco-environmental quality assessment index system was established to characterize the QTP, and the information entropy and elasticity methods were introduced to quantify the impact of land use dynamic trajectory on the eco-environmental quality. It provides a statistical measurement of system structure and more information than the traditional methods to reveal the land use change. The area change in land use on QTP was small from 1990 to 2015. The unused land and forest decreased, but those of grassland, water body, built-up land, and cultivated land increased. The overall eco-environmental quality on the QTP was low, and increased at a rate of 9.39% over the past 25 years, presenting a distribution of decreasing from southeast to northwest. The improvement in eco-environmental quality attributed to land use change was mainly due to the conversion of unused land into grassland, and ecological conservation projects also improved the local ecological environment. Conversely, the expansion of built-up land and land degradation contributed to decline in local eco-environmental quality in the Hengduan Mountains, northeastern plateau, and Qaidam Basin. The results indicated that under the influence of climate change, the changes in land use and eco-environmental quality were inconsistent in part regions, mainly including the central and southern Tibet and the border zone. Regions in which eco-environmental quality has been degraded by unreasonable land use are urgent to optimize land use management.
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Affiliation(s)
- Lina Zhang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hongqi Zhang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Erqi Xu
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.
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41
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Pan D, Yan H, Li Q, Liu D, Liu X, Zhang D, Han T, Sun B, Jiang J. Loss of grassland ecosystem service values based on potential vegetation in China. RANGELAND JOURNAL 2022. [DOI: 10.1071/rj20118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Grassland resources in China have diverse categories and span extensive areas. Existing studies have estimated the value of ecosystem services in China at different scales, but there are few reports on the potential loss of grassland ecosystem services in China. On the basis of the class-level compatibility of the two existing grassland classification systems, this study separately estimated the ecosystem service valves (ESVs) of Chinese potential grassland ecosystems (Comprehensive Sequential Classification System, CSCS) and existing grassland ecosystems (Vegetation Habitatology Classification System, VHCS). In addition, we also calculated the loss of ESVs between the two grassland classification systems and further analysed the reasons for the loss. The results are as follows: (1) the total amount of ESVs provided by the existing grassland in China was 64 929.87 × 108 Ren Min Bi (RMB) per year, in which lowland meadow and alpine meadow provide higher ESVs than the other 16 grassland classes; (2) the total ESV of Chinese potential grasslands was 83 632.88 × 108 RMB per year, of which IE29 (frigid temperate humid tundra, alpine meadow) and IF36 (frigid perhumid rain tundra, alpine meadow) contributed most to the total ESV (16.9%); (3) the ESVs of grassland in China decreased by 18 703.01 × 108 RMB per year compared with the potential value; the ESV loss mainly occurred in areas where the original grassland decreased and the secondary grassland increased; and (4) anthropogenic disturbances such as grazing, felling and indiscriminate cultivation and climate change are the main reasons for loss of ESV owing to grassland degradation.
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42
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Alongi F, Rüthers JH, Giejsztowt J, LaPaglia K, Jentsch A. Interspecific trait variability and local soil conditions modulate grassland model community responses to climate. Ecol Evol 2022; 12:e8513. [PMID: 35228858 PMCID: PMC8864100 DOI: 10.1002/ece3.8513] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 12/04/2021] [Accepted: 12/16/2021] [Indexed: 12/11/2022] Open
Abstract
Medium-to-high elevation grasslands provide critical services in agriculture and ecosystem stabilization, through high biodiversity and providing food for wildlife. However, these ecosystems face elevated risks of disruption due to predicted soil and climate changes. Separating the effects of soil and climate, however, is difficult in situ, with previous experiments focusing largely on monocultures instead of natural grassland communities. We experimentally exposed model grassland communities, comprised of three species grown on either local or reference soil, to varied climatic environments along an elevational gradient in the European Alps, measuring the effects on species and community traits. Although species-specific biomass varied across soil and climate, species' proportional contributions to community-level biomass production remained consistent. Where species experienced low survivorship, species-level biomass production was maintained through increased productivity of surviving individuals; however, maximum species-level biomass was obtained under high survivorship. Species responded directionally to climatic variation, spatially separating differentially by plant traits (including height, reproduction, biomass, survival, leaf dry weight, and leaf area) consistently across all climates. Local soil variation drove stochastic trait responses across all species, with high levels of interactions occurring between site and species. This soil variability obscured climate-driven responses: we recorded no directional trait responses for soil-corrected traits like observed for climate-corrected traits. Our species-based approach contributes to our understanding of grassland community stabilization and suggests that these communities show some stability under climatic variation.
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Affiliation(s)
- Franklin Alongi
- Department of Disturbance EcologyBayCEERUniversity of BayreuthBayreuthGermany
- Department of Plant Science and Plant PathologyMontana State UniversityBozemanMontanaUSA
| | - Jana H. Rüthers
- Department of Disturbance EcologyBayCEERUniversity of BayreuthBayreuthGermany
| | - Justyna Giejsztowt
- Department of Disturbance EcologyBayCEERUniversity of BayreuthBayreuthGermany
| | - Katrina LaPaglia
- Department of Disturbance EcologyBayCEERUniversity of BayreuthBayreuthGermany
| | - Anke Jentsch
- Department of Disturbance EcologyBayCEERUniversity of BayreuthBayreuthGermany
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Jiang R, Zou M, Qin Y, Tan G, Huang S, Quan H, Zhou J, Liao H. Modeling of the Potential Geographical Distribution of Three Fritillaria Species Under Climate Change. FRONTIERS IN PLANT SCIENCE 2022; 12:749838. [PMID: 35082804 PMCID: PMC8784777 DOI: 10.3389/fpls.2021.749838] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 11/15/2021] [Indexed: 06/14/2023]
Abstract
Fritillaria species, a well-known Chinese traditional medicine for more than 2,000 years, have become rare resources due to excessive harvesting. In order to balance the economical requirement and ecological protection of Fritillaria species, it is necessary to determine (1) the important environmental variables that were responsible for the spatial distribution, (2) distribution change in response to climate change in the future, (3) ecological niche overlap between various Fritillaria species, and (4) the correlation between spatial distribution and phylogenies as well. In this study, the areas with potential ecological suitability for Fritillaria cirrhosa, Fritillaria unibracteata, and Fritillaria przewalskii were predicted using MaxEnt based on the current occurrence records and bioclimatic variables. The result indicated that precipitation and elevation were the most important environmental variables for the three species. Moreover, the current suitable habitats of F. cirrhosa, F. unibracteata, and F. przewalskii encompassed 681,951, 481,607, and 349,199 km2, respectively. Under the scenario of the highest concentration of greenhouse gas emission (SSP585), the whole suitable habitats of F. cirrhosa and F. przewalskii reach the maximum from 2021 to 2100, while those of F. unibracteata reach the maximum from 2021 to 2100 under the scenario of moderate emission (SSP370) from 2021 to 2100. The MaxEnt data were also used to predict the ecological niche overlap, and thus high overlap occurring among three Fritillaria species was observed. The niche overlap of three Fritillaria species was related to the phylogenetic analysis despite the non-significance (P > 0.05), indicating that spatial distribution was one of the factors that contributed to the speciation diversification. Additionally, we predicted species-specific habitats to decrease habitat competition. Overall, the information obtained in this study provided new insight into the potential distribution and ecological niche of three species for the conservation and management in the future.
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Affiliation(s)
| | | | | | | | | | | | - Jiayu Zhou
- School of Life Sciences and Engineering, Southwest Jiaotong University, Chengdu, China
| | - Hai Liao
- School of Life Sciences and Engineering, Southwest Jiaotong University, Chengdu, China
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Fan Z, Bai X. Scenarios of potential vegetation distribution in the different gradient zones of Qinghai-Tibet Plateau under future climate change. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 796:148918. [PMID: 34280642 DOI: 10.1016/j.scitotenv.2021.148918] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 06/21/2021] [Accepted: 07/05/2021] [Indexed: 06/13/2023]
Abstract
The spatial distribution of potential vegetation types in Qinghai-Tibet Plateau presents a significant vertical zonation. Explicating the vertical differences of potential vegetation distribution under future climate change in Qinghai-Tibet Plateau is an important issue for understanding the response of terrestrial ecosystem to climate change. Based on the observed climate data in 1981-2010 (T0), the scenario data of RCP 2.6, RCP 4.5 and RCP 8.5 released by CMIP5 in 2011-2040 (T1), 2041-2070 (T2) and 2071-2100 (T3), and the digital elevation model (DEM) data, the Holdridge life zone (HLZ) model has been improved to simulate the scenarios of potential vegetation distribution in the different gradient zones of Qinghai-Tibet plateau. The shift model of mean center has been improved to calculate the shift direction and distance of mean center in the potential vegetation types. The ecological diversity index was introduced to compute the ecological diversity change of potential vegetation. The simulated results show that there are 17 potential vegetation types in Qinghai-Tibet Plateau. Wet tundra, high-cold moist forest and nival are the major potential vegetation types and cover 56.26% of the total area of Qinghai-Tibet Plateau. Under the three scenarios, the nival would have the largest decreased area that would be decreased by 3.340 × 104 km2 per decade, and the high-cold wet forest would have the greatest increased area that would be increased by 3.340 × 104 km2 on average per decade from T0 to T3. The potential vegetation types distributed in the alpine zone would show the fastest change ratio (11.32% per decade) and that in low mountain and other zone would show the slowest change ratio (7.54% per decade) on average. The ecological diversity and patch connectivity of potential vegetation would be decreased by 0.108% and 0.290% per decade on average from T0 to T3. In general, the potential vegetation types distributed in the high elevation area generally have a higher sensitivity to climate change in Qinghai-Tibet plateau in the future.
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Affiliation(s)
- Zemeng Fan
- State Key Laboratory of Resources and Environment Information System, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China.
| | - Xuyang Bai
- State Key Laboratory of Resources and Environment Information System, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
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Du J, He Z, Chen L, Lin P, Zhu X, Tian Q. Impact of climate change on alpine plant community in Qilian Mountains of China. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2021; 65:1849-1858. [PMID: 33974125 DOI: 10.1007/s00484-021-02141-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 03/27/2021] [Accepted: 04/26/2021] [Indexed: 06/12/2023]
Abstract
There is growing evidence that mountains are experiencing some of the highest rates of climate warming, but assessment of the ecological impacts of climate change is often limited due to a lack of long-term monitoring data for comparative study in many ecosystems. In this study, we present an empirical work for assessing ecological responses with botanical legacy data in the Qilian Mountains of China. Plot-scale and transect-wide survey was conducted for alpine shrub communities along an elevational gradient 20 years ago. Recently, we resampled the permanent plots to investigate how the community changes may be linked to climatic variability. We found no significant temporal shifts in species richness; but the community structure underwent substantial changes, as indicated by visible shifts in the relative density of dominant shrub species and the frequency of occurrence of understory herbaceous species. This reshuffling of plant community composition reflected a series of complex responses to climate change. Specifically, wet-demanding species have become more frequent due to the recently enhanced precipitation, while the replacement of some low-statured plants with different requirements for light was indirectly regulated by climate warming via reshaping the altitudinal patterns of dominant shrubs. Climate-mediated shifts in shrub species distribution altered the expected evolutional trajectory of alpine community, which increased the complexity and nonlinearity of the responses of the communities at different altitudes to climatic variability. Our results suggested that in-depth knowledge of indirect effects can facilitate to lessen the uncertainty in predicting future community dynamics in a changing climate.
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Affiliation(s)
- Jun Du
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Lanzhou, 730000, China
- Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Zhibin He
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Lanzhou, 730000, China.
- Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
| | - Longfei Chen
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Lanzhou, 730000, China
- Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Pengfei Lin
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Lanzhou, 730000, China
- Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Xi Zhu
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Lanzhou, 730000, China
- Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Quanyan Tian
- Linze Inland River Basin Research Station, Chinese Ecosystem Research Network, Lanzhou, 730000, China
- Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
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Diao C, Liu Y, Zhao L, Zhuo G, Zhang Y. Regional-scale vegetation-climate interactions on the Qinghai-Tibet Plateau. ECOL INFORM 2021. [DOI: 10.1016/j.ecoinf.2021.101413] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Influences of Climate Change and Human Activities on NDVI Changes in China. REMOTE SENSING 2021. [DOI: 10.3390/rs13214326] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The spatiotemporal evolution of vegetation and its influencing factors can be used to explore the relationships among vegetation, climate change, and human activities, which are of great importance for guiding scientific management of regional ecological environments. In recent years, remote sensing technology has been widely used in dynamic monitoring of vegetation. In this study, the normalized difference vegetation index (NDVI) and standardized precipitation–evapotranspiration index (SPEI) from 1998 to 2017 were used to study the spatiotemporal variation of NDVI in China. The influences of climate change and human activities on NDVI variation were investigated based on the Mann–Kendall test, correlation analysis, and other methods. The results show that the growth rate of NDVI in China was 0.003 year−1. Regions with improved and degraded vegetation accounted for 71.02% and 22.97% of the national territorial area, respectively. The SPEI decreased in 60.08% of the area and exhibited an insignificant drought trend overall. Human activities affected the vegetation cover in the directions of both destruction and restoration. As the elevation and slope increased, the correlation between NDVI and SPEI gradually increased, whereas the impact of human activities on vegetation decreased. Further studies should focus on vegetation changes in the Continental Basin, Southwest Rivers, and Liaohe River Basin.
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Jia J, Wang Y, Lu Y, Sun K, Lyu S, Gao Y. Driving mechanisms of gross primary productivity geographical patterns for Qinghai-Tibet Plateau lake systems. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 791:148286. [PMID: 34118660 DOI: 10.1016/j.scitotenv.2021.148286] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 05/25/2021] [Accepted: 06/01/2021] [Indexed: 06/12/2023]
Abstract
Being a fundamental property of aquatic systems, gross primary productivity (GPP) is affected by complex environmental factors, such as salinity, nutrients, pH, and sunlight. Under conditions of intensified anthropogenic activity and climate change, it is critical to understand the driving mechanisms of GPP in alpine lakes. In this study, we investigated GPP and associated environmental factors of 23 lake systems in the Qinghai-Tibet Plateau (QTP) along an altitudinal range (from 2500 m to 4500 m). Results showed an increase in chlorophyll a (Chl a) content as altitude increased and a corresponding decrease as salinity increased. Furthermore, geographical patterns of GPP were higher at the mid-gradient and lower at the extreme gradient. Higher solar radiation and water temperatures, stronger evaporation and higher salinity levels, and lower pH and higher nutrient content were all driving mechanisms of GPP in low altitudinal lake systems within high latitudinal regions. Such conditions have collectively resulted in the current GPP pattern via the promotion or inhibition of phytoplankton growth and photosynthesis. Specifically, geographical features and climate change jointly drive algal growth and GPP of alpine lake systems via internal circulation processes; however, anthropogenic activities interfere with external circulation processes for most of lower-middle altitudinal lake systems, thus playing a certain role in regulating environmental factors and GPP alongside climate change.
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Affiliation(s)
- Junjie Jia
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Yafeng Wang
- Key Laboratory of Alpine Ecology, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Yao Lu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Kun Sun
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Sidan Lyu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Yang Gao
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
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Vegetation Greenness Variations and Response to Climate Change in the Arid and Semi-Arid Transition Zone of the Mongo-Lian Plateau during 1982–2015. REMOTE SENSING 2021. [DOI: 10.3390/rs13204066] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Vegetation greenness dynamics in arid and semi-arid regions are sensitive to climate change, which is an important phenomenon in global climate change research. However, the driving mechanism, particularly for the longitudinal and latitudinal changes in vegetation greenness related to climate change, has been less studied and remains poorly understood in arid and semi-arid areas. In this study, we investigated changes in vegetation greenness and the vegetation greenness line (the mean growing season normalized difference vegetation index (NDVI) = 0.1 contour line) and its response to climate change based on AVHRR-GIMMS NDVI3g and the fifth and latest global climate reanalysis dataset from 1982 to 2015 in the arid and semi-arid transition zone of the Mongolian Plateau (ASTZMP). The results showed that the mean growing season NDVI increased from the central west to east, northeast, and southeast in ASTZMP. The vegetation greenness line migrated to the desert during 1982–1994, to the grassland during 1994–2005, and then to the desert during 2005–2015. Vegetation greenness was positively correlated with precipitation and negatively correlated with temperature. The latitudinal variation of the vegetation greenness line was mainly affected by the combination of precipitation and temperature, while the longitudinal variation was mainly affected by precipitation. In summary, precipitation was a key climatic factor driving rapid changes in vegetation greenness during the growing season of the transition zone. These results can provide meaningful information for research on vegetation coverage changes in arid and semi-arid regions.
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Greening of the Qinghai–Tibet Plateau and Its Response to Climate Variations along Elevation Gradients. REMOTE SENSING 2021. [DOI: 10.3390/rs13183712] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The vegetation of the Qinghai–Tibet Plateau (QTP) is vital to the global climate change and ecological security of China. However, the impact of climate variation on the spatial pattern and zonal distribution of vegetation in the QTP remains unclear. Accordingly, we used multisource remote-sensing vegetation indices (GIMMS-LAI, GIMMS NDVI, GLOBMAP LAI, MODIS EVI, MODIS NDVI, and MODIS NIRv), climate data, a digital elevation model, and the moving window method to investigate the changes in vegetation greenness and its response to climate variations in the QTP from 2001 to 2016. Results showed that the vegetation was greening in the QTP, which might be attributed to the increases in temperature and radiation. By contrast, the browning of vegetation may be caused by drought. Notably, the spatial patterns of vegetation greenness and its variations were linearly correlated with climate at low altitudes, and vegetation greenness was non-linearly correlated with climate at high altitudes. The Northwestern QTP needs to be focused on in regard to positive and decreased VGEG (vegetation greenness along the elevation gradient). The significantly positive VGEG was up to (34.37 ± 2.21) % of the QTP, which indicated a homogenization of vegetation greenness on elevation. This study will help us to understand the spatial distribution of vegetation greenness and VGEG in the QTP under global warming, and it will benefit ecological environment management, policymaking, and future climate and carbon sink (source) prediction.
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