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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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Qu LP, Chen J, Xiao J, De Boeck HJ, Dong G, Jiang SC, Hu YL, Wang YX, Shao CL. The complexity of heatwaves impact on terrestrial ecosystem carbon fluxes: Factors, mechanisms and a multi-stage analytical approach. ENVIRONMENTAL RESEARCH 2024; 240:117495. [PMID: 37890820 DOI: 10.1016/j.envres.2023.117495] [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: 08/25/2023] [Revised: 10/23/2023] [Accepted: 10/23/2023] [Indexed: 10/29/2023]
Abstract
Extreme heatwaves have become more frequent and severe in recent decades, and are expected to significantly influence carbon fluxes at regional scales across global terrestrial ecosystems. Nevertheless, accurate prediction of future heatwave impacts remains challenging due to a lack of a consistent comprehension of intrinsic and extrinsic mechanisms. We approached this knowledge gap by analyzing the complexity factors in heatwave studies, including the methodology for determining heatwave events, divergent responses of individual ecosystem components at multiple ecological and temporal scales, and vegetation status and hydrothermal environment, among other factors. We found that heatwaves essentially are continuously changing compound environmental stress that can unfold into multiple chronological stages, and plant physiology and carbon flux responses differs in each of these stages. This approach offers a holistic perspective, recognizing that the impacts of heatwaves on ecosystems can be better understood when evaluated over time. These stages include instantaneous, post-heatwave, legacy, and cumulative effects, each contributing uniquely to the overall impact on the ecosystem carbon cycle. Next, we investigated the importance of the timing of heatwaves and the possible divergent consequences caused by different annual heatwave patterns. Finally, a conceptual framework is proposed to establish a united foundation for the study and comprehension of the consequences of heatwaves on ecosystem carbon cycle. This instrumental framework will assist in guiding regional assessments of heatwave impacts, shedding light on the underlying mechanisms responsible for the varied responses of terrestrial ecosystems to specific heatwave events, which are imperative for devising efficient adaptation and mitigation approaches.
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Affiliation(s)
- Lu-Ping Qu
- College of JunCao Science and Ecology, Fujian Agriculture and Forestry University, Fuzhou, China.
| | - Jiquan Chen
- Center for Global Change & Earth Observations (CGCEO), 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.
| | - 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.
| | | | - Ya-Lin Hu
- College of JunCao Science and Ecology, Fujian Agriculture and Forestry University, Fuzhou, China.
| | - Yi-Xuan 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.
| | - Chang-Liang 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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Chen T, Wang Y, Peng L. Advanced time-lagged effects of drought on global vegetation growth and its social risk in the 21st century. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 347:119253. [PMID: 37806268 DOI: 10.1016/j.jenvman.2023.119253] [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: 03/21/2023] [Revised: 09/03/2023] [Accepted: 10/02/2023] [Indexed: 10/10/2023]
Abstract
Extensive studies have demonstrated the restricting effect of past and present drought conditions on vegetation growth over the past three decades. However, the underlying mechanism of the impact of prior drought on vegetation growth - along with the magnitude of its impact over the rest of the 21st century - remains uncertain. Herein, we examined the evolution and characteristics of global vegetation growth and drought for both baseline (1982-2014) and future (2015-2100) periods under four representative pathways using the gross primary productivity (GPP) and the Standardized Precipitation Evapotranspiration Index from the CMIP6. Further, we investigated the time-lagged effects of drought on vegetation growth and the intensity of population and economy exposure to drought by identifying drought-threatened areas under four emission scenarios. The results show that, at the end of the 21st century, the global terrestrial GPP will experience an increasing trend under four scenarios, especially in SSP5-8.5, with a growth rate of 0.032 kg C m-2/decade, which is 10 times higher than that in SSP1-2.6. From the SSP1-2.6 to the SSP5-8.5 scenario, the SPEI change rates are -0.03, -0.01, -0.017, and -0.018/decade, respectively, indicating that the intensity of global drought events will rise with increases in CO2 emissions. 28.3%, 24.7%, 30.4%, and 35% of global land exhibit downward mean time-lagged months in four scenarios, especially in the middle-high latitudes of the northern hemisphere (>45°N), indicating an advanced response of vegetation to drought. Nearly 8, 9.1, 12.9, and 11.5 billion people - valued at 94,138 (SSP1-2.6), 976,020 (SSP2-4.5), 526,595 (SSP3-7.0), and 204,728 (SSP5-8.5) billion US$, respectively - will be threatened by continuous drought. Globally, the population and economy exposure to moderate and extreme drought zones is larger, and the economic risk from extreme droughts is 8 times greater under the high emissions scenario than the low emissions scenario.
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Affiliation(s)
- Tiantian Chen
- Chongqing Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area, Chongqing Normal University, Chongqing, 401331, China; Chongqing Field Observation and Research Station of Surface Ecological Process in the Three Gorges Reservoir Area, Chongqing, 401331, China
| | - Yuxi Wang
- Chongqing Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area, Chongqing Normal University, Chongqing, 401331, China
| | - Li Peng
- College of Geography and Resources, Sichuan Normal University, Chengdu, 610066, China.
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Li H, Zhang F, Li J, Guo X, Zhou H, Li Y. Differential responses of CO 2 and latent heat fluxes to climatic anomalies on two alpine grasslands on the northeastern Qinghai-Tibetan Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 900:165863. [PMID: 37516184 DOI: 10.1016/j.scitotenv.2023.165863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/24/2023] [Accepted: 07/26/2023] [Indexed: 07/31/2023]
Abstract
Discrete extreme heat events, deluges, and droughts will become more frequent and disproportionately affect the processes and functions of grassland ecosystems. Here, we compared the responses of CO2 and heat fluxes to natural extreme events in 2016 in a lower alpine meadow and neighboring upper shrubland on the northeastern Qinghai-Tibetan Plateau. Unlike insensitive sensible heat flux, latent heat flux (LE) increased by 21.8 % in the meadow and by 56.4 % in the shrubland during a dry period and subsequent compound hot-dry period in August. Changes (Δ, data for 2016 minus the corresponding means from other years) in the heat flux at both sites were determined by changes in solar radiation (ΔSwin), as sufficient soil moisture was available. ΔLE was more sensitive to ΔSwin in the open-canopy shrubland, reflecting its greater capacity for evaporative cooling to buffer climate anomalies. CO2 fluxes responded weakly to extreme wet or dry events but strongly when those events were accompanied by exceptional heat. During single or compound hot events, the mean changes in total ecosystem respiration (ΔTER) increased by about 30 % in both grasslands, although ΔTER was more sensitive to changes in the topsoil temperature in the more productive meadow than in the shrubland. The mean changes in gross primary productivity (ΔGPP) fluctuated by <10 % in the warmer meadow but increased by 29.3 % in the cooler shrubland relative to the respective baseline, probably because of the differences in canopy structure and root depth and the consequent high-temperature stress on vegetation photosynthesis. The changes in net ecosystem CO2 exchange (ΔNEE) were significantly related to ΔTER in the meadow and increased by 55.8 %, whereas ΔNEE was controlled mainly by ΔGPP in the shrubland and decreased by 22.4 %. Overall, both alpine grasslands were resistant to rainfall anomalies but susceptible to exceptional warmth, with the differential responses being ascribed to canopy structure and root depth. Our results provide helpful insights based on which the carbon sequestration and water-holding functions of alpine grasslands during future climate change can be predicted.
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Affiliation(s)
- Hongqin Li
- College of Life Sciences, Luoyang Normal University, Luoyang, Henan 471934, China; Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai 810008, China; Qinghai Provincial Key Laboratory of Restoration Ecology in Cold Region, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai 810008, China
| | - Fawei Zhang
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai 810008, China; Qinghai Provincial Key Laboratory of Restoration Ecology in Cold Region, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai 810008, China.
| | - Jiexia Li
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai 810008, China; Qinghai Provincial Key Laboratory of Restoration Ecology in Cold Region, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai 810008, China
| | - Xiaowei Guo
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai 810008, China; Qinghai Provincial Key Laboratory of Restoration Ecology in Cold Region, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai 810008, China
| | - Huakun Zhou
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai 810008, China; Qinghai Provincial Key Laboratory of Restoration Ecology in Cold Region, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai 810008, China
| | - Yingnian Li
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai 810008, China; Qinghai Provincial Key Laboratory of Restoration Ecology in Cold Region, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai 810008, China
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5
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Ping J, Cui E, Du Y, Wei N, Zhou J, Wang J, Niu S, Luo Y, Xia J. Enhanced causal effect of ecosystem photosynthesis on respiration during heatwaves. SCIENCE ADVANCES 2023; 9:eadi6395. [PMID: 37878695 PMCID: PMC10599625 DOI: 10.1126/sciadv.adi6395] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 09/21/2023] [Indexed: 10/27/2023]
Abstract
Because of global warming, Earth's ecosystems have been experiencing more frequent and severe heatwaves. Heatwaves are expected to tip terrestrial carbon sequestration by elevating ecosystem respiration and suppressing gross primary productivity (GPP). Here, using the convergent cross-mapping technique, this study detected positive bidirectional causal effects between GPP and respiration in two unprecedented European heatwaves. Heatwaves enhanced the causal effect strength of GPP on respiration rather than respiration on GPP across 40 site-years of observations. Further analyses and global simulations revealed spatial heterogeneity in the heatwave response of the causal link strength between GPP and respiration, which was jointly driven by the local climate and vegetation properties. However, the causal effect strength of GPP on respiration showed considerable uncertainties in CMIP6 models. This study reveals an enhanced causal link strength between GPP and respiration during heatwaves, shedding light on improving projections for terrestrial carbon sink dynamics under future climate extremes.
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Affiliation(s)
- Jiaye Ping
- Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
- Research Center for Global Change and Complex Ecosystems, Institute of Eco-Chongming, East China Normal University, Shanghai 200241, China
| | - Erqian Cui
- Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
- Research Center for Global Change and Complex Ecosystems, Institute of Eco-Chongming, East China Normal University, Shanghai 200241, China
| | - Ying Du
- Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
- Research Center for Global Change and Complex Ecosystems, Institute of Eco-Chongming, East China Normal University, Shanghai 200241, China
| | - Ning Wei
- Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
- Research Center for Global Change and Complex Ecosystems, Institute of Eco-Chongming, East China Normal University, Shanghai 200241, China
| | - Jian Zhou
- Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
- School of Integrative Plant Science, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY, 14850, USA
| | - Jing Wang
- Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
- Research Center for Global Change and Complex Ecosystems, Institute of Eco-Chongming, East China Normal University, Shanghai 200241, China
| | - Shuli Niu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Yiqi Luo
- School of Integrative Plant Science, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY, 14850, USA
| | - Jianyang Xia
- Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
- Research Center for Global Change and Complex Ecosystems, Institute of Eco-Chongming, East China Normal University, Shanghai 200241, China
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Dong X, Qu L, Dong G, Legesse TG, Akram MA, Tong Q, Jiang S, Yan Y, Xin X, Deng J, Shao C. Mowing mitigated the sensitivity of ecosystem carbon fluxes responses to heat waves in a Eurasian meadow steppe. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 853:158610. [PMID: 36089030 DOI: 10.1016/j.scitotenv.2022.158610] [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: 05/18/2022] [Revised: 09/03/2022] [Accepted: 09/04/2022] [Indexed: 05/28/2023]
Abstract
The heat waves (HW) will be more frequent and intense in the future with increased human activity and uncertain implications for ecosystem carbon fluxes. The semi-arid Eurasian grassland is sensitive to climate change and under frequent HWs attacks. Mowing as one of the most common human practices in this region, combining with HW can have comprehensive effects on plant communities, biomass, and nutrient cycling. Hence, a 3-year (2019-2021) field manipulation experiment was conducted to assess how mowing influenced the carbon cycling under HWs, and the interactions between HWs and mowing on carbon fluxes at the community and ecosystem levels in a Eurasian meadow steppe. Over the three years, HW significantly reduced net ecosystem CO2 exchange (NEE) and gross ecosystem production (GEP) by 28 % and 8 % (P < 0.05), respectively, whereas ecosystem respiration (Re) did not show significant changes. Moderate mowing (stubble height was set at 6-8 cm) for harvest effectively mitigated ecosystem sensitivity to HWs and significantly increased ecosystem carbon fluxes (NEE, Re, and GEP), biomass and the number of species. Mowing reduced the negative impact of HWs on ecosystem carbon fluxes by about 15 % compared to HWs alone, contributing to the invasion of species such as Thalictrum squarrosum and Vicia amoena, and increased the indirect effect of HW on NEE in the structural equation model. In addition, the higher soil water content (SWC) was another effective way to reduce the impact of HWs. Therefore, mowing and higher SWC would be effective ways to counteract the negative effects of HWs on carbon fluxes in future grassland management.
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Affiliation(s)
- Xiaobing Dong
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China; National Hulunber Grassland Ecosystem Observation and Research Station & Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Luping Qu
- Forestry College, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Isotope Research Center, Fujian Normal University, Fuzhou 350002, China
| | - Gang Dong
- School of Life Science, Shanxi University, Taiyuan 030006, China
| | - Tsegaye Gemechu Legesse
- National Hulunber Grassland Ecosystem Observation and Research Station & Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Muhammad Adnan Akram
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
| | - Qi Tong
- 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 130024, China
| | - Yuchun Yan
- 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
- National Hulunber Grassland Ecosystem Observation and Research Station & Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Jianming Deng
- State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China
| | - Changliang Shao
- 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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Wanner L, Calaf M, Mauder M. Incorporating the effect of heterogeneous surface heating into a semi-empirical model of the surface energy balance closure. PLoS One 2022; 17:e0268097. [PMID: 35648756 PMCID: PMC9159583 DOI: 10.1371/journal.pone.0268097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 04/21/2022] [Indexed: 11/19/2022] Open
Abstract
It was discovered several decades ago that eddy covariance measurements systematically underestimate sensible and latent heat fluxes, creating an imbalance in the surface energy budget. Since then, many studies have addressed this problem and proposed a variety of solutions to the problem, including improvements to instruments and correction methods applied during data postprocessing. However, none of these measures have led to the complete closure of the energy balance gap. The leading hypothesis is that not only surface-attached turbulent eddies but also sub-mesoscale atmospheric circulations contribute to the transport of energy in the atmospheric boundary layer, and the contribution from organized motions has been grossly neglected. The problem arises because the transport of energy through these secondary circulations cannot be captured by the standard eddy covariance method given the relatively short averaging periods of time (~30 minutes) used to compute statistics. There are various approaches to adjust the measured heat fluxes by attributing the missing energy to the sensible and latent heat flux in different proportions. However, few correction methods are based on the processes causing the energy balance gap. Several studies have shown that the magnitude of the energy balance gap depends on the atmospheric stability and the heterogeneity scale of the landscape around the measurement site. Based on this, the energy balance gap within the surface layer has already been modelled as a function of a nonlocal atmospheric stability parameter by performing a large-eddy simulation study with idealized homogeneous surfaces. We have further developed this approach by including thermal surface heterogeneity in addition to atmospheric stability in the parameterization. Specifically, we incorporated a thermal heterogeneity parameter that was shown to relate to the magnitude of the energy balance gap. For this purpose, we use a Large-Eddy Simulation dataset of 28 simulations with seven different atmospheric conditions and three heterogeneous surfaces with different heterogeneity scales as well as one homogeneous surface. The newly developed model captures very well the variability in the magnitude of the energy balance gap under different conditions. The model covers a wide range of both atmospheric stabilities and landscape heterogeneity scales and is well suited for application to eddy covariance measurements since all necessary information can be modelled or obtained from a few additional measurements.
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Affiliation(s)
- Luise Wanner
- Institute of Meteorology and Climate Research, Atmospheric Environmental Research, Karlsruhe Institute of Technology, Garmisch-Partenkirchen, Germany
- Institute of Hydrology and Meteorology, Technische Universität Dresden, Tharandt, Germany
- * E-mail:
| | - Marc Calaf
- Department of Mechanical Engineering, University of Utah, Salt Lake City, UT, United States of America
| | - Matthias Mauder
- Institute of Meteorology and Climate Research, Atmospheric Environmental Research, Karlsruhe Institute of Technology, Garmisch-Partenkirchen, Germany
- Institute of Hydrology and Meteorology, Technische Universität Dresden, Tharandt, Germany
- Institute of Geography and Geoecology, Karlsruhe Institute of Technology, Karlsruhe, Germany
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Yuan Y, Bao A, Jiapaer G, Jiang L, De Maeyer P. Phenology-based seasonal terrestrial vegetation growth response to climate variability with consideration of cumulative effect and biological carryover. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 817:152805. [PMID: 34982988 DOI: 10.1016/j.scitotenv.2021.152805] [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: 09/21/2021] [Revised: 12/06/2021] [Accepted: 12/27/2021] [Indexed: 06/14/2023]
Abstract
Vegetation growth is influenced not only by climate variability but also by its past states. However, the differences in the degree of the climate variability and past states affecting vegetation growth over seasons are still poorly understood, particularly given the cumulative climate effects. Relying on the Normalized Difference Vegetation Index (NDVI) data from 1982 to 2014, the vegetation growing season was decomposed into three periods (sub-seasons) - green-up (GSgp), maturity (GSmp), and senescence (GSsp) - following a phenology-based definition. A distributed lag model was then utilized to analyze the time-lag effect of vegetation growth response to climatic factors including precipitation, temperature, and solar radiation during each sub-season. On this basis, the relative importance of climatic factors and vegetation growth carryover (VGC) effect on vegetation growth was quantified at the phenology-based seasonal scale. Results showed that the longest peak lag of precipitation, temperature, and solar radiation occurred in the GSmp, GSsp, and GSgp, with 1.27 (1.13 SD), 0.89 (1.02 SD), and 0.80 (1.04 SD) months, respectively. The influence of climate variability was strongest in the GSgp, and diminished over the season, while the opposite for the VGC effect. The relative influence of each climatic factor also varied between sub-seasons. Vegetation in more than 58% of areas was more affected by temperature in the GSgp, and the proportion decreased to 34.00% and 31.78% in the GSmp and GSsp, respectively. Precipitation and solar radiation acted as the dominant climatic factors in only 28.80% and 20.88% of vegetation areas in the GSgp, but they increased to 35.21%, 32.61% in the GSmp, and 38.20%, 30.02% in the GSsp, respectively. The increased regions influenced by precipitation were mainly in dry areas especially for the boreal and cool temperate climate zones, while increased regions influenced by solar radiation were primarily located in moist areas of mid-high latitudes of the Northern Hemisphere. By introducing the cumulative climate effect, our findings highlight seasonal patterns of vegetation growth affected by climate variability and the VGC effect. The results provide a more comprehensive perspective on climate-vegetation interactions, which may help us to accurately forecast future vegetation growth under accelerating global warming.
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Affiliation(s)
- Ye Yuan
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; University of Chinese Academy of Sciences, Beijing 100049, China; Department of Geography, Ghent University, Ghent 9000, Belgium
| | - Anming Bao
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; China-Pakistan Joint Research Center on Earth Sciences, CAS-HEC, Islamabad 45320, Pakistan; Sino-Belgian Laboratory for Geo-Information, Urumqi 83011, China.
| | - Guli Jiapaer
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
| | - Liangliang Jiang
- School of Geography and Tourism, Chongqing Normal University, Chongqing 401331, China
| | - Philippe De Maeyer
- Department of Geography, Ghent University, Ghent 9000, Belgium; Sino-Belgian Laboratory for Geo-Information, Ghent 9000, Belgium
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9
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Diverging Responses of Two Subtropical Tree Species (Schima superba and Cunninghamia lanceolata) to Heat Waves. FORESTS 2020. [DOI: 10.3390/f11050513] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The frequency and intensity of heat waves (HWs) has increased in subtropical regions in recent years. The mechanism underlying the HW response of subtropical trees remains unclear. In this study, we conducted an experiment with broad-leaved Schima superba (S. superba) and coniferous Cunninghamia lanceolata (C. lanceolata) seedlings to examine HW (5-day long) effects on stem water transport, leaf water use efficiency (WUE), morphology and growth, and to elucidate differences in the responses of both species. Our results indicated that HWs can significantly reduce hydraulic conductivity in both species. C. lanceolata experienced significant xylem embolism, with the percentage loss of conductivity (PLC) increasing by 40%, while S. superba showed a non-significant increase in PLC (+25%). Furthermore, HW also caused a reduction in photosynthesis rates (An), but transpiration rates (Tr) increased on the 5th day of the HW, together leading to a significant decrease in leaf WUE. From diurnal dynamics, we observed that the HW caused significant decrease of S. superba An only in the morning, but nearly the all day for C. lanceolata. During the morning, with a high vapor pressure deficit (VPD) environment, the HW increased Tr, which contributed a lot to latently cooling the foliage. In comparing the two tree species, we found that HW effects on S. superba were mostly short-term, with leaf senescence but limited or no xylem embolism. The surviving S. superba recovered rapidly, forming new branches and leaves, aided by their extensive root systems. For C. lanceolata, continued seedling growth initially but with subsequent xylem embolism and withering of shoots, led to stunted recovery and regrowth. In conclusion, apart from the direct thermal impacts caused by HW, drought stress was the main cause of significant negative effects on plant water transport and the photosynthetic system. Furthermore, S. superba and C. lanceolata showed clearly different responses to HW, which implies that the response mechanisms of broad-leaved and coniferous tree species to climate change can differ.
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10
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Qu L, Chen J, Dong G, Shao C. Heavy mowing enhances the effects of heat waves on grassland carbon and water fluxes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 627:561-570. [PMID: 29426179 DOI: 10.1016/j.scitotenv.2018.01.287] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 01/21/2018] [Accepted: 01/29/2018] [Indexed: 06/08/2023]
Abstract
Heat waves (HWs) are a type of extreme weather event that is of growing concern in the scientific community. Yet field data based on sound experiment on the variation of ecosystem CO2 levels under HWs remain rare. Additionally, ecosystems react to HWs and the coupled human activities (such as grazing in grasslands) are unknown. Thus, a 3-year field experiment was conducted to simulate HWs in conjunction with different mowing intensities that mimicking grazing in a Stipa krylovii steppe on the Mongolian Plateau. HWs significantly decreased ecosystem exchange (NEE) of CO2, ecosystem respiration (Re) and gross ecosystem productivity (GEP) by 31%, 5% and 16%, respectively, over the three years. Continuous HWs over multiple years produced cumulative effects by reducing NEE at 20%, 34% and 40% in the first, second and third HW years, respectively. During three pre-defined three periods of HWs (during HW period, after HW period in the same year, and after HW period in the next year), variations in water use efficiency indicated that the grassland ecosystem exhibited a strategy for adapting to the continuous HWs to a certain extent, by adjusting community structure or increasing litter biomass. Finally, mowing increased the effects of HWs by extending the legacy effect, such that restoration of the grassland required a greater amount of time under the combination of HWs and mowing.
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Affiliation(s)
- Luping Qu
- Forest Ecology Stable Isotope Center, Forestry College, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Jiquan Chen
- Center for Global Changes and Earth Observation/Department of Geography, Environment, and Spatial Sciences, Michigan State University, East Lansing, USA
| | - Gang Dong
- School of Life Science, Shanxi University, Taiyuan, China
| | - Changliang Shao
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China.
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11
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Shi J, Cui L, Wen K, Tian Z, Wei P, Zhang B. Trends in the consecutive days of temperature and precipitation extremes in China during 1961-2015. ENVIRONMENTAL RESEARCH 2018; 161:381-391. [PMID: 29197279 DOI: 10.1016/j.envres.2017.11.037] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 11/10/2017] [Accepted: 11/10/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND AND AIMS Consecutive climatic extremes have more intense impacts on natural ecosystems and human activities than occasional events. There were many studies about the frequency or intensity of extreme weather events, but few focused on the consecutiveness or continuousness of climatic extremes. We analyzed the temporal and spatial distributions and tendencies in the consecutive temperature and precipitation extremes in China during 1961-2015. METHODS Daily temperature and precipitation data at 1867 meteorological stations over China was used and four consecutive indices of climate extremes, i.e. cold spell duration indicator (CSDI), warm spell duration indicator (WSDI), consecutive dry days (CDD) and consecutive wet days (CWD), were calculated by RClimDex 1.0. Linear trends in the time series of consecutive days of temperature and precipitation extremes were examined and their statistical significance was evaluated using Mann-Kendall test. RESULTS AND DISCUSSION There were obvious differences in the spatial distributions of consecutive days of climate extremes in China. During 1961-2015, CSDI and CWD decreased significantly at rates of 0.9 and 0.1 days per decade respectively, while WSDI increased significantly at rate of 0.8 days per decade in China. Spatially, CSDI decreased at rates of 0-3.0 days per decade in almost all parts of China, and WSDI increased at rates of 0-2.0 days per decade in most parts of China. The spatial trends of CDD and CWD were significant only in several regions of China. CSDI and WSDI had higher percent changes than those of CDD and CWD. Changes in the CSDI and WSDI were associated with large-scale oceanic and atmospheric circulation oscillations, such as Atlantic Multidecadal Oscillation (AMO), El Niño/Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO). With global warming, there will be fewer cold extremes, more frequent hot extremes and precipitation extremes. CONCLUSIONS Given the increases in the frequency and intensity of some consecutive climatic extremes and an increasing physical exposure and socio-economic vulnerability to such extremes in China, more strategies and capacities of mitigation and adaptation to consecutive climatic extremes are essential for the local government and climate-sensitive sectors.
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Affiliation(s)
- Jun Shi
- Shanghai Climate Center, Shanghai Meteorological Bureau, Shanghai 200030, China; Shanghai Key Laboratory of Meteorology and Health, Shanghai 200030, China.
| | - Linli Cui
- Shanghai Key Laboratory of Meteorology and Health, Shanghai 200030, China; Shanghai Institute of Meteorological Science, Shanghai Meteorological Bureau, Shanghai 200030, China
| | - Kangmin Wen
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, China
| | - Zhan Tian
- Shanghai Climate Center, Shanghai Meteorological Bureau, Shanghai 200030, China; Shanghai Key Laboratory of Meteorology and Health, Shanghai 200030, China
| | - Peipei Wei
- Ecological Technique and Engineering College, Shanghai Institute of Technology, Shanghai 201418, China
| | - Bowen Zhang
- Ecological Technique and Engineering College, Shanghai Institute of Technology, Shanghai 201418, China
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12
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Shao C, Chen J, Chu H, Lafortezza R, Dong G, Abraha M, Batkhishig O, John R, Ouyang Z, Zhang Y, Qi J. Grassland productivity and carbon sequestration in Mongolian grasslands: The underlying mechanisms and nomadic implications. ENVIRONMENTAL RESEARCH 2017; 159:124-134. [PMID: 28797887 DOI: 10.1016/j.envres.2017.08.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 07/29/2017] [Accepted: 08/01/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Quantifying carbon (C) dioxide exchanges between ecosystems and the atmosphere and the underlying mechanism of biophysical regulations under similar environmental conditions is critical for an accurate understanding of C budgets and ecosystem functions. METHODS For the first time, a cluster of four eddy covariance towers were set up to answer how C fluxes shift among four dominant ecosystems in Mongolia - meadow steppe (MDW), typical steppe (TPL), dry typical steppe (DRT) and shrubland (SHB) during two growing seasons (2014 and 2015). RESULTS Large variations were observed for the annual net ecosystem exchange (NEE) from 59 to 193gCm-2, though all four sites acted as a C source. During the two growing seasons, MDW acted as a C sink, TPL and DRT were C neutral, while SHB acted as a C source. MDW to SHB and TPL conversions resulted in a 2.6- and 2.2-fold increase in C release, respectively, whereas the TPL to SHB conversion resulted in a 1.1-fold increase at the annual scale. C assimilation was higher at MDW than those at the other three ecosystems due to its greater C assimilation ability and longer C assimilation times during the day and growing period. On the other hand, C release was highest at SHB due to significantly lower photosynthetic production and relatively higher ecosystem respiration (ER). A stepwise multiple regression analysis showed that the seasonal variations in NEE, ER and gross ecosystem production (GEP) were controlled by air temperature at MDW, while they were controlled mainly by soil moisture at TPL, DRT and SHB. When air temperature increased, the NEE at MDW and TPL changed more dramatically than at DRT and SHB, suggesting not only a stronger C release ability but also a higher temperature sensitivity at MDW and TPL. CONCLUSIONS The ongoing and predicted global changes in Mongolia likely impact the C exchange at MDW and TPL more than at DRT and SHB in Mongolia. Our results suggest that, with increasing drought and vegetation type succession, a clear trend for greater CO2 emissions may result in further global warming in the future. This study implies that diverse grassland ecosystems will respond differently to climate change in the future and can be seen as nature-based solutions (NBS) supporting climate change adaptation and mitigation strategies.
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Affiliation(s)
- Changliang Shao
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Jiquan Chen
- Center for Global Change & Earth Observations (CGCEO), Michigan State University, East Lansing, MI 48823, USA.
| | - Housen Chu
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA 94720, USA
| | - Raffaele Lafortezza
- Center for Global Change & Earth Observations (CGCEO), Michigan State University, East Lansing, MI 48823, USA; Department of Agricultural and Environmental Sciences, University of Bari, Bari 70126, Italy
| | - Gang Dong
- School of Life Science, Shanxi University, Taiyuan 030006, China
| | - Michael Abraha
- Center for Global Change & Earth Observations (CGCEO), Michigan State University, East Lansing, MI 48823, USA
| | - Ochirbat Batkhishig
- Institute of Geography, Mongolian Academy of Sciences, Ulaanbarrtar 210620, Mongolia
| | - Ranjeet John
- Center for Global Change & Earth Observations (CGCEO), Michigan State University, East Lansing, MI 48823, USA
| | - Zutao Ouyang
- Center for Global Change & Earth Observations (CGCEO), Michigan State University, East Lansing, MI 48823, USA
| | - Yaoqi Zhang
- School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL 36949, USA
| | - Jiaguo Qi
- Center for Global Change & Earth Observations (CGCEO), Michigan State University, East Lansing, MI 48823, USA
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13
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Shao C, Chen J, Li L, Dong G, Han J, Abraha M, John R. Grazing effects on surface energy fluxes in a desert steppe on the Mongolian Plateau. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2017; 27:485-502. [PMID: 27761975 DOI: 10.1002/eap.1459] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 07/27/2016] [Accepted: 09/06/2016] [Indexed: 06/06/2023]
Abstract
Quantifying the surface energy fluxes of grazed and ungrazed steppes is essential to understand the roles of grasslands in local and global climate and in land use change. We used paired eddy-covariance towers to investigate the effects of grazing on energy balance (EB) components: net radiation (Rn ), latent heat (LE), sensible heat (H), and soil heat (G) fluxes on adjacent grazed and ungrazed areas in a desert steppe of the Mongolian Plateau for a two-year period (2010-2012). Near 95% of Rn was partitioned as LE and H, whereas the contributions of G and other components of the EB were 5% at an annual scale. H dominated the energy partitioning and shared ~50% of Rn . When comparing the grazed and the ungrazed desert steppe, there was remarkably lower Rn and a lower H, but higher G at the grazed site than at the ungrazed site. Both reduced available energy (Rn - G) and H indicated a "cooling effect" feedback onto the local climate through grazing. Grazing reduced the dry year LE but enhanced the wet year LE. Energy partitioning of LE/Rn was positively correlated with the canopy conductivity, leaf area index, and soil moisture. H/Rn was positively correlated with the vapor pressure deficit but negatively correlated with the soil moisture. Boosted regression tree results showed that LE/Rn was dominated by soil moisture in both years and at both sites, while grazing shifted the H/Rn domination from temperature to soil moisture in the wet year. Grazing not only caused an LE shift between the dry and the wet year, but also triggered a decrease in the H/Rn because of changes in vegetation and soil properties, indicating that the ungrazed area had a greater resistance while the grazed area had a greater sensitivity of EB components to the changing climate.
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Affiliation(s)
- Changliang Shao
- Center for Global Change & Earth Observations, Michigan State University, East Lansing, Michigan, 48823, USA
| | - Jiquan Chen
- Center for Global Change & Earth Observations, Michigan State University, East Lansing, Michigan, 48823, USA
| | - Linghao Li
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
| | - Gang Dong
- School of Life Science, Shanxi University, Taiyuan, 030006, China
| | - Juanjuan Han
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
| | - Michael Abraha
- Center for Global Change & Earth Observations, Michigan State University, East Lansing, Michigan, 48823, USA
| | - Ranjeet John
- Center for Global Change & Earth Observations, Michigan State University, East Lansing, Michigan, 48823, USA
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14
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Xu HJ, Wang XP, Yang TB. Trend shifts in satellite-derived vegetation growth in Central Eurasia, 1982-2013. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 579:1658-1674. [PMID: 27919557 DOI: 10.1016/j.scitotenv.2016.11.182] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 11/24/2016] [Accepted: 11/25/2016] [Indexed: 06/06/2023]
Abstract
Central Eurasian vegetation is critical for the regional ecological security and the global carbon cycle. However, climatic impacts on vegetation growth in Central Eurasia are uncertain. The reason for this uncertainty lies in the fact that the response of vegetation to climate change showed nonlinearity, seasonality and differences among plant functional types. Based on remotely sensed vegetation index and in-situ meteorological data for the years 1982-2013, in conjunction with the latest land cover type product, we analyzed how vegetation growth trend varied across different seasons and evaluated vegetation response to climate variables at regional, biome and pixel scales. We found a persistent increase in the growing season NDVI over Central Eurasia during 1982-1994, whereas this greening trend has stalled since the mid-1990s in response to increased water deficit. The stalled trend in the growing season NDVI was largely attributed by summer and autumn NDVI changes. Enhanced spring vegetation growth after 2002 was caused by rapid spring warming. The response of vegetation to climatic factors varied in different seasons. Precipitation was the main climate driver for the growing season and summer vegetation growth. Changes in temperature and precipitation during winter and spring controlled the spring vegetation growth. Autumn vegetation growth was mainly dependent on the vegetation growth in summer. We found diverse responses of different vegetation types to climate drivers in Central Eurasia. Forests were more responsive to temperature than to precipitation. Grassland and desert vegetation responded more strongly to precipitation than to temperature in summer but more strongly to temperature than to precipitation in spring. In addition, the growth of desert vegetation was more dependent on winter precipitation than that of grasslands. This study has important implications for improving the performance of terrestrial ecosystem models to predict future vegetation response to climate change.
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Affiliation(s)
- Hao-Jie Xu
- Shapotou Desert Research and Experiment Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xin-Ping Wang
- Shapotou Desert Research and Experiment Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.
| | - Tai-Bao Yang
- College of Earth Environmental Sciences, Lanzhou University, Lanzhou 730000, China
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15
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Drought and Carbon Cycling of Grassland Ecosystems under Global Change: A Review. WATER 2016. [DOI: 10.3390/w8100460] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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16
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Lafortezza R, Chen J. The provision of ecosystem services in response to global change: Evidences and applications. ENVIRONMENTAL RESEARCH 2016; 147:576-579. [PMID: 26944091 DOI: 10.1016/j.envres.2016.02.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Revised: 02/16/2016] [Accepted: 02/29/2016] [Indexed: 06/05/2023]
Abstract
As a consequence of the global increase in economic and societal prosperity, ecosystems and natural resources have been substantially exploited, degraded, or even destroyed in the last century. To prevent further deprivation of the quality of ecosystems, the ecosystem services concept has become a central issue in environmental studies. A growing number of environmental agencies and organizations worldwide are now embracing integrated approaches to plan and manage ecosystems, sharing a goal to maintain the long-term provision of ecosystem services for sustainability. A daunting challenge in this process is to move from general pronouncements about the tremendous benefits that ecosystems provide to society to defensible assessments of their services. In other words, we must move beyond the scientific evidences of the ecosystem services concept to its practical applications. In this work, we discuss the theoretical foundations and applications of ecosystem services with a focus on the assessment of ecosystem service trade-offs and synergies at various spatial and temporal scales. Here, we offer examples of the main factors related to land use management that may affect the provision of ecosystem services and provide direction for future research on ecosystem services and related nature-based solutions. We also provide a briefing on the major topics covered in this Special Issue, which focuses on the provision of ecosystem services in the context of global change.
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Affiliation(s)
- Raffaele Lafortezza
- Department of Agricultural and Environmental Sciences, Università degli Studi di Bari "A. Moro", Via Amendola 165/A, 70126 Bari, Italy; CGCEO/Geography, Michigan State University, East Lansing, MI 48823, USA.
| | - Jiquan Chen
- CGCEO/Geography, Michigan State University, East Lansing, MI 48823, USA
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