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An explanation of labor migration and grain output growth:Findings of a case study in eastern Tibetan Plateau

Journal of Geographical Sciences 2016年第4期26卷 484-500页

作者：阎建忠张镱锂花晓波杨亮 College of Resources and Environment Southwest University Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCAS University of Chinese Academy of Sciences Institute of Geography University of Hamburg

Although there has been rapid rural-urban migration in rural China since the 1980s, the total grain production of China saw a continuous increase. As of today, the relationship between labor migration and grain output growth remains partial and contradictory. The main aim of this empirical study is to examine some specific measures adopted by peasants to deal with labor shortage and maintain grain output growth. Using tracking survey, participatory rural appraisal methods, and land plot investigation, we investigate 274 households and 1405 arable land plots in four villages in two stages in Jinchuan county, southwestern China. The results show that continuous emigration of labor from the four villages caused the abandon- ment of a small amount of land, decreased labor intensity, and reduced multiple cropping index, shifting from ＂corn-wheat＂ multiple cropping pattern to the ＂corn＂ cropping pattern, which means labor shortage in some households. At the same time, owing to surplus labor in the villages, the peasants utilize a series of means to offset the negative impacts of labor migration on grain output, such as cropland transfer, labor exchange in the busy seasons, and the substitution of capital and technology for labor. The econometric analysis also shows that labor migration boosts grain production. This study provides a reasonable explanation of grain output growth under rural-urban migration.

关键词： labor migration land use change labor intensity capital intensity grain output

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A global moderate resolution dataset of gross primary production of vegetation for 2000-2016

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Scientific data 2017年第1期4卷 170165-170165页

作者： Zhang, Yao Xiao, Xiangming Wu, Xiaocui Zhou, Sha Zhang, Geli Qin, Yuanwei Dong, Jinwei Center for Spatial Analysis Department for Microbiology and Plant Biology University of Oklahoma Norman OK 73019 United States Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Institute of Biodiversity Science Fudan University 200433 Shanghai China State Key Laboratory of Hydroscience and Engineering Department of Hydraulic Engineering Tsinghua University 100084 Beijing China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS 100101 Beijing China

Accurate estimation of the gross primary production (GPP) of terrestrial vegetation is vital for understanding the global carbon cycle and predicting future climate change. Multiple GPP products are currently available based on different methods, but their performances vary substantially when validated against GPP estimates from eddy covariance data. This paper provides a new GPP dataset at moderate spatial (500 m) and temporal (8-day) resolutions over the entire globe for 2000-2016. This GPP dataset is based on an improved light use efficiency theory and is driven by satellite data from MODIS and climate data from NCEP Reanalysis II. It also employs a state-of-the-art vegetation index (VI) gap-filling and smoothing algorithm and a separate treatment for C3/C4 photosynthesis pathways. All these improvements aim to solve several critical problems existing in current GPP products. With a satisfactory performance when validated against in situ GPP estimates, this dataset offers an alternative GPP estimate for regional to global carbon cycle studies.

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Contributions of climate, varieties, and agronomic management to rice yield change in the past three decades in China

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Frontiers of Earth Science 2016年第2期10卷 315-327页

作者： He ZHANG Fulu TAO Dengpan XIAO Wenjiao SHI Fengshan LIU Shuai ZHANG Yujie LIU Meng WANG Huizi BAI Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Institute of Geographical Sciences Hebei Academy of Sciences Shijiazhuang 050011 China Juncao Research Institute Fujian Agriculture and Forestry University Fuzhou 350002 China Qufu Normal University Rizhao 276826 China

The long-term field experiment data at four representative agro-meteorological stations, together with a crop simulation model, were used to disentangle the contributions of climate change, variety renewal, and fertilization management to rice yield change in the past three decades. We found that during 1981-2009 varieties renewal increased rice yield by 16%-52%, management improvement increased yield by 0-16%, and the contribu- tions of climate change to rice yield varied from - 16% to 10%. Varieties renewal and management improvement offset the negative impacts of climate change on rice production. Among the major climate variables, decreases in solar radiation reduced rice yield on average by 0.1% per year. The impact of temperature change had an explicit spatial pattern. It increased yield by 0.04%-0.4% per year for single rice at Xinbin and Ganyu station and for late rice at Tongcheng station, by contrast reduced yield by 0.2%- 0.4% per year for single rice at Mianyang station and early rice at Tongcheng station. During 1981-2009, rice varieties renewal was characterized by increases in thermal requirements, grain number per spike and harvest index. The new varieties were less sensitive to climate change than old ones. The development of high thermal require- ments, high yield potential and heat tolerant rice varieties, together with improvement of agronomic management, should be encouraged to meet the challenges of climate change and increasing food demand in future.

关键词： adaptation climate change food security,impact cultivar management

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Hydrological monitoring and seasonal forecasting:Progress and perspectives

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Journal of Geographical Sciences 2016年第7期26卷 904-920页

作者：汤秋鸿张学君段青云黄诗峰袁星崔惠娟李哲刘星才 Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research CAS University of Chinese Academy of Sciences State Key Laboratory of Earth Surface Processes and Resource Ecology College of Global Change and Earth System Science Beijing Normal University Remote Sensing Technology Application Center China Institute of Water Resources and Hydropower Research RCE-TEA Institute of Atmospheric Physics CAS Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS

Hydrological monitoring and seasonal forecasting is an active research field because of its potential applications in hydrological risk assessment, preparedness and mitigation. In recent decades, developments in ground and satellite measurements have made the hydrometeorological information readily available, and advances in information technology have facilitated the data analysis in a real-time manner. New progress in climate research and modeling has enabled the prediction of seasonal climate with reasonable accuracy and increased resolution. These emerging techniques and advances have enabled more timely acquisition of accurate hydrological fluxes and status, and earlier warning of extreme hydrological events such as droughts and floods. This paper gives current state-of-the-art understanding of the uncertainties in hydrological monitoring and forecasting, reviews the efforts and progress in operational hydrological monitoring system assisted by observations from various sources and experimental seasonal hydrological forecasting, and briefly introduces the current monitoring and forecasting practices in China. The grand challenges and perspectives for the near future are also discussed, including acquiring and extracting reliable information for monitoring and forecasting, predicting realistic hydrological fluxes and states in the river basin being significantly altered by human activity, and filling the gap between numerical models and the end user. We highlight the importance of understanding the needs of the operational water management and the priority to transfer research knowledge to decision-makers.

关键词： hydrological monitoring hydrological forecasting uncertainty modeling remote sensing climate model

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Glacier Changes on the Qiangtang Plateau between 1976 and 2015:A Case Study in the Xainza Xiegang Mountains

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Journal of Resources and Ecology 2017年第1期8卷 97-104页

作者： NIE Yong YANG Chao ZHANG Yili LIU Linshan XU Xia Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan 610041 China Department of Geography and Resource Sciences Sichuan Normal University Chengdu Sichuan 610101 China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

Xainza County on the Qiangtang Plateau（QP） spans a transitionally climatic and eco-environmental zone and is therefore a very sensitive *** in this area are one of the most important kinds of land cover as well as key water resources,yet our understanding of their current status and spatio-temporal change remains *** landsat images,this study investigated the current distribution of glaciers（2015） in the Xainza Xiegang Mountains as well as the spatio-temporal changes that took place over six time periods between 1976 and *** show that,in 2015,131 glaciers covered a total area of 74.59 ± 5.25 km^2,mainly located between 5,600 and 6,000 m above sea level（a.s.l）.Between 1976 and 2015,the total number of glaciers increased by 12,while their areas decreased by 24.98%（24.83 km^2）.Glacial retreat has induced a loss of water resources of 11.77 × 10~8 m^3 over the last 39 years,while spatial heterogeneities in glacial changes across various sub-basins,aspects,and altitudinal zones are also clearly *** warming is the key factor driving this continuous glacial retreat;the high-quality dataset presented in this paper for the Xainza Xiegang study area is crucial for the ongoing assessment of climatic and eco-environmental changes.

关键词： Glacier water resources remote sensing landsat images Qiangtang Plateau

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Author Correction: Near-real-time monitoring of global CO2 emissions reveals the effects of the COVID-19 pandemic

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Nature communications 2020年第1期11卷 6292页

作者： Zhu Liu Philippe Ciais Zhu Deng Ruixue Lei Steven J Davis Sha Feng Bo Zheng Duo Cui Xinyu Dou Biqing Zhu Rui Guo Piyu Ke Taochun Sun Chenxi Lu Pan He Yuan Wang Xu Yue Yilong Wang Yadong Lei Hao Zhou Zhaonan Cai Yuhui Wu Runtao Guo Tingxuan Han Jinjun Xue Olivier Boucher Eulalie Boucher Frédéric Chevallier Katsumasa Tanaka Yiming Wei Haiwang Zhong Chongqing Kang Ning Zhang Bin Chen Fengming Xi Miaomiao Liu François-Marie Bréon Yonglong Lu Qiang Zhang Dabo Guan Peng Gong Daniel M Kammen Kebin He Hans Joachim Schellnhuber Department of Earth System Science Tsinghua University Beijing China. zhuliu@***. Laboratoire des Sciences du Climat et de l'Environnement LSCE CEA CNRS UVSQ Centre d'Etudes Orme de Merisiers Gif-sur-Yvette France. Department of Earth System Science Tsinghua University Beijing China. Department of Meteorology and Atmospheric Science The Pennsylvania State University University Park PA USA. Department of Earth System Science University of California Irvine 3232Croul Hall Irvine CA USA. Division of Geological and Planetary Sciences California Institute of Technology Pasadena CA USA. Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA. Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment Technology School of Environmental Science and Engineering Nanjing University of Information Science and Technology Nanjing 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 Beijing China. Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China. School of Environment Tsinghua University Beijing China. School of Mathematical School Tsinghua University Beijing China. Department of Mathematical Sciences Tsinghua University Beijing 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. Institut Pierre-Simon Laplace Sorbonne Université/CNRS Paris France. Université Paris Dauphine Place du Maréchal de Lattre de Tassigny 75016 Paris France.

A Correction to this paper has been published: https://***/10.1038/s41467-020-20254-5.

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Assessment of effectiveness of nature reserves on the Tibetan Plateau based on net primary production and the large sample comparison method

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Journal of Geographical Sciences 2016年第1期26卷 27-44页

作者：张镱锂胡忠俊祁威吴雪摆万奇李兰晖丁明军刘林山王兆锋郑度 Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCAS CAS Center for Excellence in Tibetan Plateau Earth Sciences University of Chinese Academy of Sciences Key Laboratory of Poyang Lake Wetland and Watershed Research Ministry of EducationJiangxi Normal University

Twenty-one typical coupled large samples were chosen from areas within and surrounding nature reserves on the Tibetan Plateau using the large sample comparison method(LSCM).To evaluate the effectiveness of the nature reserves in protecting the ecological environment,the alpine grassland net primary production(NPP) of these coupled samples were compared and the differences between them before and after their establishment as protected areas were *** results showed that:(1) With respect to the alpine grassland NPP,the ecological and environmental conditions of most nature reserves were more fragile than those of the surrounding areas and also lower than the average values for the Tibetan Plateau.(2) Of the 11 typical nature reserves selected,the positive trend in the NPP for Manzetang was the most significant,whereas there was no obvious trend in *** the exception of Selincuo,the annual NPP growth rate in the nature reserves covered by alpine meadow and wetland was higher than that in nature reserves consisting of alpine steppe and alpine desert.(3) There were notable findings in 21 typical coupled samples:(a) After the establishment of the nature reserves,the annual rate of increase in the NPP in 76% of samples inside nature reserves and 82% of samples inside national nature reserves was higher than that of the corresponding samples outside nature reserves.(b) The effectiveness of ecological protection of the Mid-Kunlun,Changshagongma,Zoige and Selincuo(Selin Co) nature reserves was significant; the effectiveness of protection was relatively sig-nificant in most parts of the Sanjiangyuan and Qiangtang nature reserves,whereas in south-east Manzetang and north Taxkorgan the protection effectiveness was not obvious.(c) The ecological protection effectiveness was significant in nature reserves consisting of alpine meadow,but was weak in nature reserves covered by alpine *** study also shows that the advantage of large sample comparison method

关键词： nature reserves protection effectiveness large sample comparison method net primary production Tibetan Plateau

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Corrigendum to "Effect of biochar on the presence of nutrients and ryegrass growth in the soil from an abandoned indigenous coking site: The potential role of biochar in the revegetation of contaminated site" [Sci. Total Environ. 601-602 (2017) 469-477]

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The Science of the total environment 2018年 626卷 1505页

作者： Guixiang Zhang Yuen Zhu Xiaofang Guo Zhiwang Han Qiusheng He Fengsong Zhang College of Environment and Safety Taiyuan University of Science and Technology Taiyuan 030024 Shanxi Province China. College of Environment and Resources Shanxi University Taiyuan 030006 Shanxi Province China. Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China. Electronic address: zhangfs@***.

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Spatio-temporal Characteristics of Disturbance of land Use Change on Major Ecosystem Function Zones in China

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Chinese Geographical Science 2015年第5期25卷 523-536页

作者： NING Jia LIU Jiyuan ZHAO Guosong Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences

In recent years, because of increasing human activities, ecosystems have been substantially disturbed and their service functions have been greatly compromised. Based on the effect of land use changes on the major ecosystem services, we estimated the ecosystem comprehensive anthropogenic disturbance index(ECADI) and analyzed the spatio-temporal characteristics of changes in the ECADI in China from 1990 to 2010. The average ECADI of the major ecosystem function zones in China in 2010 is approximately 0.382. The ECADI of Northeast China and North China is slightly higher than that of Northwest China and Southwest China. Most zones have slight changes in the ECADI. The average increases of ECADI in the major ecosystem function zones in China from 1990 to 2000 and from 2000 to 2010 are 0.0024 and 0.0002, respectively. The increase is mainly due to reclamation and urbanization, whereas the decrease is due to the implementation of ecosystem protection policies. During the last 20 years, the ECADI of water resources conservation zones increased first, and then stopped. The ECADI of soil conservation zones increased first, and then declined. The ECADI of sandstorm prevention zones, biodiversity conservation zones and flooding mitigation zones increased continuously. Our results may provide proposals to the government regarding land use planning and ecosystem protection plans in the major ecosystem zones. The major ecosystem function zones in the western part of China have been protected effectively. However, the major ecosystem function zones in the eastern part of China require more protection in the future.

关键词： land use change major ecosystems services disturbance spatiotemporal patterns China

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Remote sensing-based artificial surface cover classification in Asia and spatial pattern analysis

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Science China Earth Sciences 2016年第9期59卷 1720-1737页

作者： KUANG WenHui CHEN LiJun LIU JiYuan XIANG WeiNing CHI WenFeng LU DengSheng YANG TianRong PAN Tao LIU AiLin Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China National Geomatics Center of China Beijing 100830 China School of Ecological and Environmental Sciences East China Normal University Shanghai 200241 China University of North Carolina at Charlotte NC 28223 USA School of Environmental & Resource Sciences Zhejiang A&F University Hangzhou 311300 China Michigan State University East Lansing M148823 USA State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100049 China

Artificial surfaces, characterized with intensive land-use changes and complex landscape structures, are important indicators of human impacts on terrestrial ecosystems. Without high-resolution land-cover data at continental scale, it is hard to evaluate the impacts of urbanization on regional climate, ecosystem processes and global environment. This study constructed a hierarchical classification system for artificial surfaces, promoted a remote sensing method to retrieve subpixel components of artificial surfaces from 30-m resolution satellite imageries(Globe land30) and developed a series of data products of high-precision urban built-up areas including impervious surface and vegetation cover in Asia in 2010. Our assessment, based on multisource data and expert knowledge, showed that the overall accuracy of classification was 90.79%. The mean relative error for the impervious surface components of cities was 0.87. The local error of the extracted information was closely related to the heterogeneity of urban buildings and vegetation in different climate zones. According to our results, the urban built-up area was 18.18×104 km2, accounting for 0.59% of the total land surface areas in Asia; urban impervious surfaces were 11.65×104 km2, accounting for 64.09% of the total urban built-up area in Asia. Vegetation and bare soils accounted for 34.56% of the urban built-up areas. There were three gradients: a concentrated distribution, a scattered distribution and an indeterminate distribution from east to west in terms of spatial pattern of urban impervious surfaces. China, India and Japan ranked as the top three countries with the largest impervious surface areas, which respectively accounted for 32.77%, 16.10% and 11.93% of the urban impervious surface area of Asia. We found the proportions of impervious surface and vegetation cover within urban built-up areas were closely related to the economic development degree of the country and regional climate environment. Built-

关键词： Artificial surface cover City Impervious surface Vegetation cover Remote sensing classification Asia

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