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Lei Y, Zhou J, Yao T, Bird BW, Yu Y, Wang S, Yang K, Zhang Y, Zhai J, Dai Y. Overflow of Siling Co on the central Tibetan Plateau and its environmental impacts. Sci Bull (Beijing) 2024:S2095-9273(24)00531-0. [PMID: 39129118 DOI: 10.1016/j.scib.2024.07.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Revised: 07/05/2024] [Accepted: 07/08/2024] [Indexed: 08/13/2024]
Affiliation(s)
- Yanbin Lei
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China.
| | - Jing Zhou
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Tandong Yao
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Broxton W Bird
- Department of Earth Sciences, Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis, IN 46202, USA
| | - Yifan Yu
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shujin Wang
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kun Yang
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084, China
| | - Yinsheng Zhang
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Jianqing Zhai
- National Climate Center, China Meteorological Administration, Beijing 100081, China
| | - Yufeng Dai
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
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2
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Zhu H, Xiong X, Liu B, Liu G. Lakes-scale pattern of eukaryotic phytoplankton diversity and assembly process shaped by electrical conductivity in central Qinghai-Tibet Plateau. FEMS Microbiol Ecol 2024; 100:fiad163. [PMID: 38100388 PMCID: PMC10791044 DOI: 10.1093/femsec/fiad163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 11/15/2023] [Accepted: 12/13/2023] [Indexed: 12/17/2023] Open
Abstract
Phytoplankton are the main primary producers in aquatic ecosystems and play an important role in food web and geochemical cycles. Its diversity, community structure, and assembly process are influenced by several factors. Alpine lake ecosystems are relatively weak and extremely sensitive to global climate change. However, the impact of climate change on phytoplankton in Qinghai-Tibet Plateau lakes and their responses are still unclear. In this study, we analyzed the diversity, environmental drivers, and assembly process of phytoplankton community in the central QTP lakes. The phytoplankton of these lakes can be primarily distinguished into freshwater and brackish types, with significant differences in species diversity and community dissimilarity. Both shared nearly same key environmental factors that significantly affecting phytoplankton such as EC, and brackish lakes were also positively correlative with TN. Stochastic process was predominant in phytoplankton assembly. Additionally, freshwater and brackish lakes were dominated by dispersal limitation and heterogeneous selection respectively. Alpine lakes had significant EC thresholds, and their diversity and assembly processes changed significantly around the thresholds. The present findings have important implications for understanding and predicting the response of lake phytoplankton communities to climate change and for making decisions to protect the ecological resources of alpine lakes.
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Affiliation(s)
- Huan Zhu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Xiong Xiong
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Benwen Liu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Guoxiang Liu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
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Ren Z, Jia X, Zhang Y, Ma K, Zhang C, Li X. Biogeography and environmental drivers of zooplankton communities in permafrost-affected lakes on the Qinghai-Tibet Plateau. Glob Ecol Conserv 2022. [DOI: 10.1016/j.gecco.2022.e02191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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4
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Bian X, Liang X, Weckworth B, Jyal D, Hull V, Yang L. Spatial density estimate of the snow leopard, Panthera uncia, in the Central Tibetan Plateau, China. Integr Zool 2022. [PMID: 36049233 DOI: 10.1111/1749-4877.12672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Knowledge of large carnivore population abundance is essential for wildlife management and conservation, but these data are often difficult to obtain in inherently low-density species. In particular, the snow leopard, Panthera uncia, an enigmatic cat occupying remote mountains in Central Asia, has received insufficient assessments of its population abundance because of logistical and methodological challenges. Here, we aimed to develop a robust density estimation of snow leopards based on 81 days of camera trapping within a contiguous and previously unsurveyed 1,950 km2 area of habitat on the Tibetan Plateau (Mayue Township, Shenzha County, Tibet Autonomous Region, China). By applying spatially explicit capture-recapture models, we produced an estimate of 1.40 (95%CI: 1.06-1.84) individuals per 100 km2 . Results also suggested sex-specific variation in range of movement around activity centers, with male (N = 10, σ = 4.02) movement considerably greater than female (N = 8, σ = 1.84) movement. The findings can serve as a reliable baseline reference for assessing the population trends of this endangered felid species with future estimates. This study will provide context to contribute towards a better understanding of ecological factors shaping the distribution and abundance of snow leopards and the related conservation measures needed to sustain their long-term survival on the Tibetan Plateau. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Xiaoxing Bian
- School of Natural Resources and Environment, University of Florida, Gainesville, Florida, USA.,Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, Florida, USA.,Wildlife Conservation Society China, Chaoyang District, Beijing, Beijing, China
| | - Xuchang Liang
- Wildlife Conservation Society China, Chaoyang District, Beijing, Beijing, China
| | | | - Dorje Jyal
- Wildlife Conservation Society China, Chaoyang District, Beijing, Beijing, China
| | - Vanessa Hull
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, Florida, USA
| | - Le Yang
- Tibet Plateau Institute of Biology, Lhasa, China
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5
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Jin L, Li Z, Wang C, Wang Y, Li X, Yang J, Zhao Y, Guo B. Contrasting population differentiation in two sympatric Triplophysa loaches on the Qinghai–Tibet Plateau. Front Genet 2022; 13:958076. [PMID: 36092882 PMCID: PMC9452750 DOI: 10.3389/fgene.2022.958076] [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: 05/31/2022] [Accepted: 07/15/2022] [Indexed: 11/25/2022] Open
Abstract
Genetic differentiation in aquatic organisms is usually shaped by drainage connectivity. Sympatric aquatic species are thus expected to show similar population differentiation patterns and similar genetic responses to their habitats. Water bodies on the Qinghai–Tibet Plateau (QTP) have recently experienced dramatic physicochemical changes, threatening the biodiversity of aquatic organisms on the “roof of the world.” To uncover ecological genetics in Tibetan loaches (Triplophysa)—the largest component of the QTP ichthyofauna—we characterized population differentiation patterns and adaptive mechanisms to salinity change in two sympatric and phylogenetically closely related Tibetan loaches, T. stewarti and T. stenura, by integrating population genomic, transcriptomic, and electron probe microanalysis approaches. Based on millions of genome-wide SNPs, the two Tibetan loach species show contrasting population differentiation patterns, with highly geographically structured and clear genetic differentiation among T. stewarti populations, whereas there is no such observation in T. stenura, which is also supported by otolith microchemistry mapping. While limited genetic signals of parallel adaption to salinity changes between the two species are found from either genetic or gene expression variation perspective, a catalog of genes involved in ion transport, energy metabolism, structural reorganization, immune response, detoxification, and signal transduction is identified to be related to adaptation to salinity change in Triplophysa loaches. Together, our findings broaden our understanding of the population characteristics and adaptive mechanisms in sympatric Tibetan loach species and would contribute to biodiversity conservation and management of aquatic organisms on the QTP.
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Affiliation(s)
- Ling Jin
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Zitong Li
- CSIRO Agriculture and Food, Canberra, ACT, Australia
| | - Chongnv Wang
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Yingnan Wang
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Xinxin Li
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Jian Yang
- Assessment and Resource Conservation in Middle and Lower Reaches of the Yangtze River, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Yahui Zhao
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Baocheng Guo
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, China
- Academy of Plateau Science and Sustainability, Qinghai Normal University, Xining, China
- *Correspondence: Baocheng Guo,
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6
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The Role of Thermokarst Lake Expansion in Altering the Microbial Community and Methane Cycling in Beiluhe Basin on Tibetan Plateau. Microorganisms 2022; 10:microorganisms10081620. [PMID: 36014037 PMCID: PMC9412574 DOI: 10.3390/microorganisms10081620] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 08/05/2022] [Accepted: 08/07/2022] [Indexed: 11/16/2022] Open
Abstract
One of the most significant environmental changes across the Tibetan Plateau (TP) is the rapid lake expansion. The expansion of thermokarst lakes affects the global biogeochemical cycles and local climate regulation by rising levels, expanding area, and increasing water volumes. Meanwhile, microbial activity contributes greatly to the biogeochemical cycle of carbon in the thermokarst lakes, including organic matter decomposition, soil formation, and mineralization. However, the impact of lake expansion on distribution patterns of microbial communities and methane cycling, especially those of water and sediment under ice, remain unknown. This hinders our ability to assess the true impact of lake expansion on ecosystem services and our ability to accurately investigate greenhouse gas emissions and consumption in thermokarst lakes. Here, we explored the patterns of microorganisms and methane cycling by investigating sediment and water samples at an oriented direction of expansion occurred from four points under ice of a mature-developed thermokarst lake on TP. In addition, the methane concentration of each water layer was examined. Microbial diversity and network complexity were different in our shallow points (MS, SH) and deep points (CE, SH). There are differences of microbial community composition among four points, resulting in the decreased relative abundances of dominant phyla, such as Firmicutes in sediment, Proteobacteria in water, Thermoplasmatota in sediment and water, and increased relative abundance of Actinobacteriota with MS and SH points. Microbial community composition involved in methane cycling also shifted, such as increases in USCγ, Methylomonas, and Methylobacter, with higher relative abundance consistent with low dissolved methane concentration in MS and SH points. There was a strong correlation between changes in microbiota characteristics and changes in water and sediment environmental factors. Together, these results show that lake expansion has an important impact on microbial diversity and methane cycling.
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Zhou J, Wang L, Zhong X, Yao T, Qi J, Wang Y, Xue Y. Quantifying the major drivers for the expanding lakes in the interior Tibetan Plateau. Sci Bull (Beijing) 2022; 67:474-478. [PMID: 36546167 DOI: 10.1016/j.scib.2021.11.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 11/01/2021] [Accepted: 11/02/2021] [Indexed: 01/06/2023]
Affiliation(s)
- Jing Zhou
- State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China.
| | - Lei Wang
- State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Xiaoyang Zhong
- State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Tandong Yao
- State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jia Qi
- State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Yuanwei Wang
- State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Yongkang Xue
- Department of Geography, University of California, Los Angeles, CA 90095-1524, USA
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8
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Qinghai-Tibetan Plateau Greening and Human Well-Being Improving: The Role of Ecological Policies. SUSTAINABILITY 2022. [DOI: 10.3390/su14031652] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Appropriate human activities can have significantly positive effects on vegetation dynamics. In the past 50 years, various ecological policies have improved both ecological change and human well-being in the Qinghai–Tibetan Plateau (QTP), efficiently achieving multiple Sustainable Development Goals (SDGs) of the United Nations’ 2030 Agenda for Sustainable Development. During 1981–2017, the annual mean normalized difference vegetation index (NDVI) of the protected areas (PAs) tended to increase significantly at a rate of 2.93 × 10−4/a (p < 0.01), while non-PAs only increased by 0.6 × 10−4/a (p < 0.5). Improvement in the NDVI of the PAs is more obvious than that of non-PAs. Specifically, the earlier the establishment of the Pas is, the more significant the greening effect will be. Moreover, ecological protection has not slowed improvements in human welfare; on the contrary, the Human Development Index (HDI) has nearly doubled in the past 40 years. In terms of global ecological construction, the Chinese government has demonstrated the responsibilities of a large country in global ecological governance. Chinese initiatives can guide other nations in contributing to the global sustainability aspirations embodied in the 2030 SDGs Agenda. This study can be used as a reference for other countries in the world to coordinate the development of ecological protection and well-being.
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Cheng J, Song C, Liu K, Fan C, Ke L, Chen T, Zhan P, Yao J. Satellite and UAV-based remote sensing for assessing the flooding risk from Tibetan lake expansion and optimizing the village relocation site. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 802:149928. [PMID: 34464806 DOI: 10.1016/j.scitotenv.2021.149928] [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: 02/07/2021] [Revised: 07/12/2021] [Accepted: 08/22/2021] [Indexed: 06/13/2023]
Abstract
Climate change in recent decades led to the remarkable expansions for most lakes in endorheic basins of the Tibetan Plateau (TP). Enlarged lake inundation areas may pose adverse effects and potential threats on the local human living environment, especially for high-risk villages adjacent to rapidly expanding lakes. Taking a rapidly expanding lake, Angzi Co in the central TP as a study case, we investigated the flooding risk of lake growth on the local living environment and proposed an optimized solution of village relocation selection on the basis of satellite and unmanned aerial vehicle (UAV) remote sensing. The detection of spatiotemporal variations of Angzi Co using optical and altimetric satellite observations revealed a significant area and water level increase by 81.28 km2 and 5.78 m, respectively, from 2000 to 2020. We also assessed the vertical accuracy of multi-source digital elevation model (DEM) products using Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2) altimetry data and further examined the flooding risk and potential influences of lake expansion on adjacent settlements (Guozha Village). Results indicated that UAV-DEM achieves excellent advantages in depicting details of lake shoreline variations and simulating potential submergence regions, followed by Advanced Land Observing Satellite World 3D DEM (AW3D DEM). Moreover, assuming that Angzi Co maintains the water level at a growth rate of 0.29 m/a (the average change rate during 2000-2020), the village will be submerged in approximate 10 years based on our assessment. Furthermore, we designed an optimal relocation site southwest of Guozha Village and approximately 3 km away based on the GIS-MVDA method and field investigations. An initial remote sensing-based approach for assessing the flooding risk from dramatic lake expansions in the TP and optimizing the village relocation site was proposed in this study to provide an essential scientific reference for formulating risk mitigation solutions under future climate change scenarios.
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Affiliation(s)
- Jian Cheng
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; College of Surveying and Geotechnical Engineering, Henan Polytechnic University, Jiaozuo 454000, China
| | - Chunqiao Song
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
| | - Kai Liu
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| | - Chenyu Fan
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; College of Surveying and Geotechnical Engineering, Henan Polytechnic University, Jiaozuo 454000, China
| | - Linghong Ke
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China; College of Hydrology and Water Resources, Hohai University, Nanjing 211100, China
| | - Tan Chen
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| | - Pengfei Zhan
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| | - Jiepeng Yao
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; College of Surveying and Geotechnical Engineering, Henan Polytechnic University, Jiaozuo 454000, China
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10
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LaeNet: A Novel Lightweight Multitask CNN for Automatically Extracting Lake Area and Shoreline from Remote Sensing Images. REMOTE SENSING 2020. [DOI: 10.3390/rs13010056] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Variations of lake area and shoreline can indicate hydrological and climatic changes effectively. Accordingly, how to automatically and simultaneously extract lake area and shoreline from remote sensing images attracts our attention. In this paper, we formulate lake area and shoreline extraction as a multitask learning problem. Different from existing models that take the deep and complex network architecture as the backbone to extract feature maps, we present LaeNet—a novel end-to-end lightweight multitask fully CNN with no-downsampling to automatically extract lake area and shoreline from remote sensing images. Landsat-8 images over Selenco and the vicinity in the Tibetan Plateau are utilized to train and evaluate our model. Experimental results over the testing image patches achieve an Accuracy of 0.9962, Precision of 0.9912, Recall of 0.9982, F1-score of 0.9941, and mIoU of 0.9879, which align with the mainstream semantic segmentation models (UNet, DeepLabV3+, etc.) or even better. Especially, the running time of each epoch and the size of our model are only 6 s and 0.047 megabytes, which achieve a significant reduction compared to the other models. Finally, we conducted fieldwork to collect the in-situ shoreline position for one typical part of lake Selenco, in order to further evaluate the performance of our model. The validation indicates high accuracy in our results (DRMSE: 30.84 m, DMAE: 22.49 m, DSTD: 21.11 m), only about one pixel deviation for Landsat-8 images. LaeNet can be expanded potentially to the tasks of area segmentation and edge extraction in other application fields.
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Yang Y, Deng Y, Tuo Y, Li J, He T, Chen M. Study of the thermal regime of a reservoir on the Qinghai-Tibetan Plateau, China. PLoS One 2020; 15:e0243198. [PMID: 33347489 PMCID: PMC7751983 DOI: 10.1371/journal.pone.0243198] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 11/17/2020] [Indexed: 11/19/2022] Open
Abstract
The Qinghai-Tibetan Plateau region has unique meteorological characteristics, with low air temperature, low air pressure, low humidity, little precipitation, and strong diurnal variation. A two-dimensional hydrodynamic CE-QUAL-W2 model was configured for the Pangduo Reservoir to better understand the thermal structure and diurnal variation inside the reservoir under the local climate and hydrological conditions on the Qinghai-Tibetan Plateau. Observation data were used to verify the model, and the results showed that the average error of the 6 profile measured monthly from August to December 2016 was 0.1°C, and the root-mean-square error (RMSE) was 0.173°C. The water temperature from August 2016 to September 2017 was simulated by inputting measured data as model inputs. The results revealed that the reservoir of the Qinghai-Tibetan Plateau was a typical dimictic reservoir and the water mixed vertically at the end of March and the end of October. During the heating period, thermal stratification occurred, with strong diurnal variation in the epilimnion. The mean variance of the diurnal water temperature was 0.10 within a 5 m water depth but 0.04 in the whole water column. The mixing mode of inflow changed from undercurrent, horizontal-invaded flow and surface layer flow in one day. In winter, the diurnal variation was weak due to the thermal protection of the ice cover, while the mean variance of diurnal water temperature was 0.00 within both 5 m and the whole water column. Compared to reservoirs in areas with low altitude but the same latitude, significant differences occurred between the temperature structure of the low-altitude reservoir and the Pangduo Reservoir (P<0.01). The Pangduo Reservoir presented a shorter stratification period and weaker stratification stability, and the annual average SI value was 26.4 kg/m2, which was only 7.5% that of the low-altitude reservoir. The seasonal changes in the net heat flux received by the surface layers determined the seasonal cycle of stratification and mixing in reservoirs. This study provided a scientific understanding of the thermal changes in stratified reservoirs under the special geographical and meteorological conditions on the Qinghai-Tibetan Plateau. Moreover, this model can serve as a reference for adaptive management of similar dimictic reservoirs in cold and high-altitude areas.
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Affiliation(s)
- Yanjing Yang
- State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, China
| | - Yun Deng
- State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, China
| | - Youcai Tuo
- State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, China
| | - Jia Li
- State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, China
| | - Tianfu He
- State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, China
| | - Min Chen
- State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, China
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Neupane B, Wang J, Kang S, Zhang Y, Chen P, Rai M, Guo J, Yu S, Thapa P. Black carbon and mercury in the surface sediments of Selin Co, central Tibetan Plateau: Covariation with total carbon. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 721:137752. [PMID: 32182467 DOI: 10.1016/j.scitotenv.2020.137752] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 03/03/2020] [Accepted: 03/04/2020] [Indexed: 06/10/2023]
Abstract
Tibetan Plateau (TP) is an important geographical region for investigating the long-range transport of pollutants as limited emission sources exist in this region. In this study, based on analysis of 61 surface samples, we report the spatial distribution and concentrations of BC, Hg, total organic carbon (TOC) and inorganic carbon (IC) in surface sediments of Selin Co, the largest lake in central Tibet. The mean BC and Hg concentrations were 0.62 ± 0.34 mg/g and 32.03 ± 9.88 ng/g (range: 0.03-1.47 mg/g and 13.83-51.81 ng/g respectively), which were lower than the values from other lakes in the Himalayan-Tibetan Plateau (HTP). BC and Hg exhibited similar spatial distribution in the surface sediments. Similarly, the mean TOC and IC were 2.19 ± 1.46% and 3.13 ± 1.07% (range: 0.0007-7.78% and 0.30-5.30% respectively). BC/TOC ratio, as well as char/soot ratio, suggests biomass burning as a major source of BC in the sediments via the influence of long-range transport. The positive correlation between the concentrations of BC and Hg suggests similar emission sources or transport pathway. Concentrations of BC and Hg were higher in fine grain particles (size <~50 μm) which were capable of transport and deposit in the deeper part of the lake, as suggested by a significant relationship between water depth and particle size. This study elucidates the extent of pollution in very recent ages and also could serve as the basis for paleo-environmental studies in future.
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Affiliation(s)
- Bigyan Neupane
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Junbo Wang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes/Nam Co Observation and Research Station (NAMORS), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, 100049 Beijing, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China.
| | - Yulan Zhang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Pengfei Chen
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Mukesh Rai
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Junming Guo
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Siwei Yu
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes/Nam Co Observation and Research Station (NAMORS), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Poonam Thapa
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, 100049 Beijing, China
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Zhang F, Shi X, Zeng C, Wang L, Xiao X, Wang G, Chen Y, Zhang H, Lu X, Immerzeel W. Recent stepwise sediment flux increase with climate change in the Tuotuo River in the central Tibetan Plateau. Sci Bull (Beijing) 2020; 65:410-418. [PMID: 36659232 DOI: 10.1016/j.scib.2019.12.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 12/09/2019] [Accepted: 12/09/2019] [Indexed: 01/21/2023]
Abstract
The riverine sediment flux (SF) is an essential pathway for nutrients and pollutants delivery and considered as an important indicator of land degradation and environment changes. With growing interest in environmental changes over the Tibetan Plateau (TP), this work investigated the variation of the SF in response to climate change in the headwater of the Yangtze River over the past 30 years. Annual time series of hydro-meteorological variables during 1986-2014 indicate significantly increasing trends of air temperature, precipitation, ground temperature, river discharge, suspended sediment concentration and SF. Stepwise changes were identified with significantly higher values of the above variables in 1998-2014 compared with 1986-1997, which could potentially be attributed to the strong 1997 El Niño event. Double-mass plots indicated that both meltwater and rainfall contributed to the increased river discharge while the increased SF mostly resulted from enhanced erosive power and transport capacities of the increased discharge. However, it was buffered by a decrease in sediment source due to the shift of maximum monthly rainfall from June/July to July/August during which period a denser vegetation cover prevents soil erosion. Partial least squares structural equation modeling analysis confirmed the dominance of warming on the increase of discharge amplified by increased precipitation. It also confirmed that the increased precipitation drives the increase in suspended sediment concentration. Both processes conspire and equally contribute to the stepwise increase of SF. This study provides important insights into the controlling processes for recent SF changes and gives guidance for water and soil conservation on the TP.
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Affiliation(s)
- Fan Zhang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100101, China.
| | - Xiaonan Shi
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China.
| | - Chen Zeng
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Li Wang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100101, China
| | - Xiong Xiao
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100101, China
| | - Guanxing Wang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100101, China
| | - Yao Chen
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100101, China
| | - Hongbo Zhang
- College of Water Resources & Civil Engineering, China Agricultural University, Beijing 100083, China
| | - Xixi Lu
- Department of Geography, National University of Singapore, Arts Link 1, 117570, Singapore
| | - Walter Immerzeel
- Department of Physical Geography, Utrecht University, Utrecht 80115, the Netherlands
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Liu X, Zhang X, Lin Y, Jin L, Chen F. Strengthened Indian summer monsoon brought more rainfall to the western Tibetan Plateau during the early Holocene. Sci Bull (Beijing) 2019; 64:1482-1485. [PMID: 36659554 DOI: 10.1016/j.scib.2019.07.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 07/03/2019] [Accepted: 07/04/2019] [Indexed: 01/21/2023]
Affiliation(s)
- Xiangjun Liu
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou 730070, China; Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China.
| | - Xiaojian Zhang
- School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China
| | - Yanluan Lin
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, and Joint Center for Global Change Studies, Tsinghua University, Beijing 100084, China
| | - Liya Jin
- School of Atmoshpheric Sciences, Chengdu University of Information Technology, Chengdu 610225, China
| | - Fahu Chen
- Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China; CAS Key Laboratory of Alpine Ecology, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
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A robust but variable lake expansion on the Tibetan Plateau. Sci Bull (Beijing) 2019; 64:1306-1309. [PMID: 36659659 DOI: 10.1016/j.scib.2019.07.018] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 07/02/2019] [Accepted: 07/04/2019] [Indexed: 01/21/2023]
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