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Hydrochemical regime and its mechanism in Yamzhog Yumco Basin, South Tibet

Journal of Geographical Sciences 2017年第9期27卷 1111-1122页

作者： ZHE Meng ZHANG Xueqin WANG Buwei SUN Rui ZHENG Du Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Rubber Research Institute Chinese Academy of Tropical Agriculture Sciences Danzhou 571737 Hainan China

The hydrochemistry of alpine lakes reflects water characteristic and its response to climatic change. Over 300 water samples had been collected from 52 sites of 5 lakes and 7 inflowing rivers in the Yamzhog Yumco Basin, South Tibet, during 2009-2014, basing which the hydrochemical regime and its mechanism were analyzed along with the adoption of hydrological investigations in 1979 and 1984 as well. Results revealed that the waters were hard with weak alkalinity for the Yamzhog Yumco Basin. Most of them were fresh, and the rest were slightly saline. The hydrochemical types of 5 lakes （i.e., Lake Yamzhog Yum Co, Puma Yum Co, Bajiu Co, Kongmu Co, and Chert Co） were SO4^2--HCO3^--Mg^2＋-Na^＋, HCO3^-- SO4^2--Mg^2＋-Ca^2＋, SO4^2--Mg^2＋-Na^＋, SO4^2--HCO3^--Ca^2＋, and SO4^2--Na^＋-Mg^2＋-Ca^2＋, respectively. As for rivers, HCO3^- and SO4^2- were the major anions, and Ca2. was the dominant cation. Lake Yamzhog Yum Co, the largest lake in the basin, exhibited remarkable spatial variations in hydrochemistry at its surface but irregular changes with depth. The weathering of evaporates and carbonates, together with evaporation and crystallization, were the major mechanisms controlling the hydrochemistry of waters in the Yamzhog Yumco Basin. Global warming also had significant impacts on hydrochemical variations.

关键词： hydrochemicai regime control mechanism Piper diagram Gibbs model Yamzhog Yumco Basin alpine lake

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Modelling the integrated effects of land use and climate change scenarios on forest ecosystem aboveground biomass, a case study in Taihe County of China

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Journal of Geographical Sciences 2017年第2期27卷 205-222页

作者： WU Zhuo DAI Erfu GE Quansheng XI Weimin WANG Xiaofan Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and NaturalResources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Department of Biological and Health Sciences Texas A&M University Kingsville Texas 78363 USA Key Laboratory of Land Use Ministry of Land and Resources China Land-Surveying and Planning InstituteBeijing 100035 China

Global and regional environmental changes such as land use and climate change have significantly integrated and interactive effects on forest. These integrated effects will undoubtedly alter the distribution, function and succession processes of forest ecosystems. In order to adapt to these changes, it is necessary to understand their individual and integrated effects. In this study, we proposed a framework by using coupling models to gain a better understanding of the complex ecological processes. We combined an agent-based model for land use and land cover change（ABM/LUCC）, an ecosystem process model（PnET-Ⅱ）, and a forest dynamic landscape model（LANDIS-Ⅱ） to simulate the change of forest aboveground biomass（AGB） which was driven by land use and climate change factors for the period of 2010–2050 in Taihe County of southern China, where subtropical coniferous plantations dominate. We conducted a series of land use and climate change scenarios to compare the differences in forest AGB. The results show that：（1） land use, including town expansion, deforestation and forest conversion and climate change are likely to influence forest AGB in the near future in Taihe County.（2） Though climate change will make a good contribution to an increase in forest AGB, land use change can result in a rapid decrease in the forest AGB and play a vital role in the integrated simulation. The forest AGB under the integrated scenario decreased by 53.7%（RCP2.6 ＋ land use）, 57.2%（RCP4.5 ＋ land use）, and 56.9%（RCP8.5 ＋ land use） by 2050, which is in comparison to the results under separate RCPs without land use disturbance.（3） The framework can offer a coupled method to better understand the complex and interactive ecological processes, which may provide some supports for adapting to land use and climate change, improving and optimizing plantation structure and function,and developing measures for sustainable forest management.

关键词： RCPs plantation forest aboveground biomass ABM LANDIS-Ⅱ Taihe County

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Development of quantitative methods for detecting climate contributions to boundary shifts in farming-pastoral ecotone of northern China

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Journal of Geographical Sciences 2017年第9期27卷 1059-1071页

作者： SHI Wenjiao LIU Yiting SHI Xiaoli Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Re- sources Research CAS Beijing 100101 China State Key Laboratory of Remote Sensing Science Beijing Normal University Beijing 100875 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Environmental Evolvement and Ecological Construction of Hebei Province College of Resources and Environment Sciences Hebei Normal University Shijiazhuang 050024 China

The quantitative effect of climate change on fragile regions has been a hot topic in the field of responses to climate change. Previous studies have qualitatively documented the impacts of climate change on boundary shifts in the farming-pastoral ecotone （FPE）; however, the quantitative methods for detecting climate contributions remain relatively limited. Based on long-term data of meteorological stations and interpretations of land use since 1970, climate and land use boundaries of the 1970s, 1980s, 1990s and 2000s were delineated. To detect climate contributions to the FPE boundary shifts, we developed two quantitative methods to explore the spatial-temporal pattern of climate and land use boundary at the east-west （or south-north）（FishNet method） and transect directions （Digital Shoreline Analysis System, DSAS method）. The results indicated that significant differences were exhibited in climate boundaries, land use boundaries, as well as climate contributions in different regions during different periods. The northwest FPE had smaller variations, while the northeast FPE had greater shifts. In the northwest part of the southeast fringe of the Greater Hinggan Mountains and the Inner Mongolian Plateau, the shifts of climate boundaries were significantly related to the land use boundaries. The climate contributions at an east-west direction ranged from 10.7% to 44.4%, and those at a south-north direction varied from 4.7% to 55.9%. The majority of the results from the DSAS were consistent with those from the FishNet. The DSAS method is more accurate and suitable for precise detection at a small scale, whereas the FishNet method is simple to conduct statistical analysis rapidly and directly at a large scale. Our research will be helpful to adapt to climate change, to develop the productive potential, as well as to protect the environment of the FPE in northern China.

关键词： farming-pastoral ecotone （FPE） in northern China climate change land use contribution quantitative detection

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Urban Expansion and Spatiotemporal Relationships with Driving Factors Revealed by Geographically Weighted Logistic Regression

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Journal of Resources and Ecology 2017年第3期8卷 277-286页

作者： DONG Guanglong XU Erqi ZHANG Hongqi Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Bcijing 100049 China

Urbanization improves our lives but also threatens human health and sustainable development. Revealing the spatiotemporal pattern of urban expansion and spatiotemporal relationships with driving forces, especially in terms of the ubiquitous and fast growing small city, is a crucial prerequisite to solving these problems and realizing sustainable development. Kunshan, China was used as a case study here. Eleven variables from four aspects covering physical, socioeconomic, accessibility and neighborhood were selected, and logistic regression and geographically weighted logistic regression modeling were employed to explore spatiotemporal relationships from 1991-2014. Results reveal that urban expansion in Kunshan shows an accelerating tendency with annual expansion from 2000-2014 four times higher than for 1991-2000. More importantly, the annual expansion rate of Kunshan of 28.42% in 2000-2014 is higher than that of a large city. Urban expansion and related factors have spatiotemporal varying relationships. From a global perspective, the closer to a city, town, main road and the higher the GDP, the more likely a region will undergo urbanization. Interestingly, the effect of population on urban expansion is decreasing, especially in developed areas, and the effect of distance to lake is enhanced. From a local perspective, the magnitude and even the sign of the coefficients vary across the study area. However, the range of the coefficient of GWLR is around that of the corresponding variable in LR, and the sign of most variables in GWLR is consistent with that of corresponding variables in LR. GWLR surpasses LR with the same explanatory variables in revealing regional differences and improving model reliability. Based on these findings, more attention should be given to small cities in China. Promoting the connotation of city culture and public services to realize New-type Urbanization and regional diversity policy in order to manage urban expansion scientifically are als

关键词： urban expansion spatiotemporal variation spatial heterogeneity geographically weighted logistic regression China

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Assessment of Changes in the Value of Ecosystem Services in the Koshi River Basin,Central High Himalayas Based on Land Cover Changes and the CA-Markov Model

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Journal of Resources and Ecology 2017年第1期8卷 67-76页

作者： ZHAO Zhilong WU Xue ZHANG Yili GAO Jungang Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of the Chinese Academy of Sciences Beijing 100049 China

Climate warming and economic developments have created pressures on the ecological systems that human populations rely on,and this process has contributed to the degradation of ecosystems and the loss of ecosystem *** this study,Landsat satellite data were chosen as the data source and the Koshi River Basin（KB） in the central high Himalayas as the study *** in land cover and changes in the value of ecosystem services between 1990 and 2010 were analyzed and the land cover pattern of the KB in 2030 and 2050 was modeled using the CA-Markov *** in land cover and in the value of ecosystem services in the KB for the period 2010–2050 were then *** value of ecosystem services in the KB was found to decrease by 2.05×10~8 USD y^（-1） between 1990 and *** these results,the services value of forest,snow/glacier and barren area decreased,while that of cropland *** 1990 to 2050,forest showed the largest reduction in ecosystem services value,as much as 11.87×10~8 USD y^（-1）,while cropland showed the greatest increase,by 3.05×10~8 USD y^（-1）.Deforestation and reclamation in Nepal contributed to a reduction in the value of ecosystem services in the *** areas that were transformed into water bodies brought about an increase in ecosystem services value in the lower reaches of the Koshi *** general,this process is likely to be related to increasing human activity in the KB.

关键词： ecosystem services CA-Markov land cover Himalayas Koshi River Basin

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Using Max Ent Model to Predict Suitable Habitat Changes for key Protected Species in Koshi Basin,Central Himalayas

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Journal of Resources and Ecology 2017年第1期8卷 77-87页

作者： LIU Linshan ZHAO Zhilong ZHANG Yili WU Xue Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of the Chinese Academy of Sciences Beijing 100049 China

Because of its landscape heterogeneity,Koshi Basin（KB） is home to one of the world＇s most abundant,diverse group of *** change evaluations for key protected species are very important for biodiversity protection in this *** on current and future world climate and land cover data,MaxE nt model was used to simulate potential habitat changes for key protected *** results shows that the overall accuracy of the model is high（AUC 0.9）,suggesting that the MaxE nt-derived distributions are a close approximation of real-world distribution *** valley around Chentang Town and Dram Town in China,and Lamabagar and the northern part of Landtang National Park in Nepal are the most important regions for the protection of the habitat in *** habitat area of Grus nigricollis,Panax pseudoginseng,and Presbytis entellus is expected to decrease in future climate and land cover *** focus should be placed on protecting forests and wetlands since these are the main habitats for these species.

关键词： MaxE nt model Land use Habitat loss Koshi Basin Himalayas

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Major Elements in Soils Along a 2.8-km Altitudinal Gradient on the Tibetan Plateau,China

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Pedosphere 2016年第6期26卷 895-903页

作者： WANG Zhaofeng Alfred E.HARTEMINK ZHANG Yili ZHANG Hua DING Mingjun Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences University of Wisconsin-Madison Department of Soil ScienceFD Hole Soils Lab Key Laboratory of Poyang Lake and Watershed Resarch Ministry of EducationJiangxi Normal University

There are a series of special mountain soils on the Tibetan Plateau of China in an alpine environment for the high altitude. However, very few studies have focused on major soil elements in relation to soil formation in this area. Aluminum （Al）, iron （Fe）, calcium （Ca）, sodium （Na）, potassium （K） and magnesium （Mg） contents of 237 topsoil samples covering a 2.8-km altitudinal gradient in uncultivated areas along the Qinghai-Tibet Railway of China were measured using inductively coupled plasma atomic emission spectroscopy. The spatial distribution of the elements and its relationship to the parent rocks and climatic parameters were analyzed. Soils along the gradient are derived from a range of parent materials, but most are less than 30 cm deep with little development （Cambisols）. Soil Al, Fe and Mg contents showed a decreasing trend from the start station （Xining Station） to end station （Lhasa Station） of the Qinghai-Tibet Railway, whereas soil K and Na contents were relative stable from Xining Station to the Kunlun Mountains and then increased gradually. Soil Ca content was lower in the southern part of the Tanggula Mountains. The major soil element contents clearly reflected the parent rock and climatic influences. Soils with higher Ca content appeared in areas with Ca-Mg carbonate rocks, soils with higher Al were found in areas with silicate-rich and high-Al silicate clastic rocks and silicate-rich aluminosilicate loose sediments. Soils with higher K and Na contents appeared in areas with high-K, high-Na and silicate-rich aluminosilicate rocks. Soil Na and K contents were affected by temperature, whereas the contents of Mg, Fe, Ca and Al were more affected by precipitation. Soil Na and K contents increased with increasing temperatures, whereas the contents of Mg, Fe, Ca and Al decreased with increasing precipitation. This analysis provides a relationship between soil properties and rapidly changing environmental conditions. The data can be used to investigate the

关键词： alpine environment climate mountain soil parent material precipitation temperature pedogenesis soil formation

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COVID-19 causes record decline in global CO2 emissions

arXiv

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arXiv 2020年

作者： Liu, Zhu Ciais, Philippe Deng, Zhu Lei, Ruixue Davis, Steven J. Feng, Sha Zheng, Bo Cui, Duo Dou, Xinyu He, Pan Zhu, Biqing Lu, Chenxi Ke, Piyu Sun, Taochun Wang, Yuan Yue, Xu Wang, Yilong Lei, Yadong Zhou, Hao Cai, Zhaonan Wu, Yuhui Guo, Runtao Han, Tingxuan Xue, Jinjun Boucher, Olivier Boucher, Eulalie Chevallier, Frederic Wei, Yimin Zhong, Haiwang Kang, Chongqing Zhang, Ning Chen, Bin Xi, Fengming Marie, François Zhang, Qiang Guan, Dabo Gong, Peng Kammen, Daniel M. He, Kebin Schellnhuber, Hans Joachim Department of EarthSystem Science Tsinghua University Beijing100084 China Laboratoire des Sciences du Climate et de l'Environnement LSCE Orme de Merisiers Gif-sur-Yvette91191 France Department of Meteorology andAtmospheric Science The Pennsylvania State University University ParkPA16802 United States Department of Earth System Science University of California Irvine 3232 Croul Hall IrvineCA92697-3100 United States Division of Geological and Planetary Sciences California Institute of Technology PasadenaCA United States Jet Propulsion Laboratory California Institute of Technology PasadenaCA United States Nanjing210044 China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Climate Change Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing100029 China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences Beijing100029 China School of Environment Tsinghua University Beijing100084 China School of Mat hemat ical School T singhua University Beijing100084 China Department of Mathematical Sciences Tsinghua University Beijing100084 China Center of Hubei Cooperative Innovation for Emissions Trading System Wuhan China Faculty of Management and Economics Kunming University of Science and Technology 13 Kunming China Economic Research Centre of Nagoya University Furo-cho Chikusa-ku Nagoya Japan Institute Pierre-Simon Laplace Sorbonne Université CNRS Paris France Center for Energy and Environmental Policy Research Beijing Institute of Technology Beijing China Department of Electrical Engineering Tsinghua University Beijing100084 China Jinan University Guangzhou China Beijing Normal University Beijing China Institute of Applied Ecology Chinese Academy of Sciences Shenyang China Energy and Resources Group Goldman School of Pub

The considerable cessation of human activities during the COVID-19 pandemic has affected global energy use and CO2 emissions. Here we show the unprecedented decrease in global fossil CO2 emissions from January to April 2020 was of 7.8% (938 Mt CO2 with a +6.8% of 2-σ uncertainty) when compared with the period last year. In addition other emerging estimates of COVID impacts based on monthly energy supply1 or estimated parameters2, this study contributes to another step that constructed the near-real-time daily CO2 emission inventories based on activity from power generation (for 29 countries), industry (for 73 countries), road transportation (for 406 cities), aviation and maritime transportation and commercial and residential sectors emissions (for206 countries). The estimates distinguished the decline of CO2 due to COVID-19 from the daily, weekly and seasonal variations as well as the holiday events. The COVID-related decreases in CO2 emissions in road transportation (340.4 Mt CO2, -15.5%), power (292.5 Mt CO2, -6.4% compared to 2019), industry (136.2 Mt CO2, -4.4%), aviation (92.8 Mt CO2, -28.9%), residential (43.4 Mt CO2, - 2.7%), and international shipping (35.9Mt CO2, -15%). Regionally, decreases in China were the largest and earliest (234.5 Mt CO2,-6.9%), followed by Europe (EU-27 & UK) (138.3 Mt CO2, -12.0%) and the U.S. (162.4 Mt CO2, -9.5%). The declines of CO2 are consistent with regional nitrogen oxides concentrations observed by satellites and ground-based networks, but the calculated signal of emissions decreases (about 1Gt CO2) will have little impacts (less than 0.13ppm by April 30, 2020) on the overserved global CO2 concertation. However, with observed fast CO2 recovery in China and partial re-opening globally, our findings suggest the longer-term effects on CO2 emissions are unknown and should be carefully monitored using multiple measures. Copyright © 2020, The Authors. All rights reserved.

关键词： Carbon dioxide

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Crop cover reconstruction and its effects on sediment retention in the Tibetan Plateau for 1900-2000

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Journal of Geographical Sciences 2017年第7期27卷 786-800页

作者： LI Shicheng WANG Zhaofeng ZHANG Yili Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research (IGSNRR) CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100101 China School of Public Administration China University of Geosciences Wuhan 430074 China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China

Geographically explicit historical land use and land cover datasets are increasingly required in studies of climatic and ecological effects of human activities. In this study, using historical population data as a proxy, the provincial cropland areas of Qinghai province and the Tibet Autonomous Region （TAR） for 1900, 1930, and 1950 were estimated. The cropland areas of Qinghai and the TAR for 1980 and 2000 were obtained from published statistical data with revisions. Using a land suitability for cultivation model, the provincial cropland areas for the 20th century were converted into crop cover datasets with a resolution of 1 x 1 km. Finally, changes of sediment retention due to crop cover change were assessed using the sediment delivery ratio module of the Integrated Valuation of Ecosystem Services and Trade-offs （In- VEST） model （version 3.3.1）. There were two main results. （1） For 1950-1980 the fractional cropland area increased from 0.32% to 0.48% and land use clearly intensified in the Tibetan Plateau （TP）, especially in the Yellow River-Huangshui River Valley （YHRV） and the mid- stream of the Yarlung Zangbo River and its two tributaries valley （YRTT）. For other periods of the 20th century, stability was the main trend. （2） For 1950-1980, sediment export increased rapidly in the Minhe autonomous county of the YHRV, and in the Nianchu River and Lhasa River basins of the YRTT, which means that sediment retention clearly decreased in these regions over this period. The results of this assessment provide scientific support for con- servation planning, development planning, or restoration activities.

关键词： cropland reconstruction ecosystem services INVEST model the 20th century Qinghai province the Tibet Autonomous Region

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Blood Pressure Associated with Arsenic Methylation and Arsenic Metabolism Caused by Chronic Exposure to Arsenic in Tube Well Water

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Biomedical and Environmental Sciences 2017年第5期30卷 333-342页

作者： WEI Bing Gan YE Bi Xiong YU Jiang Ping YANG Lin Sheng LI Hai Rong XIA Ya Juan WU Ke Gong Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Institute of Environmental Health and Related Product Safety Chinese Center for Disease Control and PreventionBeijing 100021China Inner Mongolia Center for Endemic Disease Control and Research Huhhot 010031Inner MongoliaChina

Objective The effects of arsenic exposure from drinking water, arsenic metabolism, and arsenic methylation on blood pressure（BP） were observed in this study. Methods The BP and arsenic species of 560 participants were determined. Logistic regression analysis was applied to estimate the odds ratios of BP associated with arsenic metabolites and arsenic methylation capability. Results BP was positively associated with cumulative arsenic exposure（CAE）. Subjects with abnormal diastolic blood pressure（DBP）, systolic blood pressure（SBP）, and pulse pressure（PP） usually had higher urinary i As（inorganic arsenic）, MMA（monomethylated arsenic）, DMA（dimethylated arsenic）, and TAs（total arsenic） than subjects with normal DBP, SBP, and PP. The i As%, MMA%, and DMA% differed slightly between subjects with abnormal BP and those with normal BP. The PMI and SMI were slightly higher in subjects with abnormal PP than in those with normal PP. Conclusion Our findings suggest that higher CAE may elevate BP. Males may have a higher risk of abnormal DBP, whereas females have a higher risk of abnormal SBP and PP. Higher urinary i As may increase the risk of abnormal BP. Lower PMI may elevate the BP. However, higher SMI may increase the DBP and SBP, and lower SMI may elevate the PP.

关键词： Arsenic Arsenic methylation Arsenic metabolism Blood pressure Drinking water

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