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A landscape management analysis framework and its preliminary application in Ejina Oasis, Northwest China
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作者 youhua ran Yan Zhao 《Research in Cold and Arid Regions》 CSCD 2019年第3期239-247,共9页
The implementation of integrated landscape management to support local and regional human well-being is crucial in arid regions,but its application to date is very limited.Although analytical frameworks have been esta... The implementation of integrated landscape management to support local and regional human well-being is crucial in arid regions,but its application to date is very limited.Although analytical frameworks have been established to maximize ecosystem services via trade-offs between different landscape configurations,consumption factors such as water resources are rarely and weakly considered in such frameworks.In this paper,an improved integrated landscape-management analysis framework,called the Consumption-integrated Landscape Management to Ecosystem Service(CLMES),is proposed.In this framework,consumption factors are integrated at the same level as ecosystem services.The improved analytical framework is then used to assess and optimize landscape design in the Ejina Oasis,an extremely arid region in western China.Three landscape conditions(past,current,and future)are evaluated,based on the CLMES.Our results indicate that the Heihe River water-allocation program effectively promoted ecosystem services in the Ejina Oasis from 2000 to 2011.However,the excessive expansion of cropland led to a slight decline in habitat quality.An optimized landscape configuration and policy suggestions are proposed,which may be beneficial to the improvement of total water-use efficiency,oasis stability,and resilience of the ecological?social system in the Ejina Oasis. 展开更多
关键词 ECOSYSTEM services ARID region water RESOURCES land-use planning REMOTE sensing
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TanSat: a new star in global carbon monitoring from China 被引量:9
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作者 youhua ran Xin Li 《Science Bulletin》 SCIE EI CAS CSCD 2019年第5期284-285,共2页
Accurate monitoring of changes in atmospheric carbon dioxide(C02)coneentration and carbon sinks/sources distribution are an important prerequisite for comprehensively understanding the global carbon cycle and correctl... Accurate monitoring of changes in atmospheric carbon dioxide(C02)coneentration and carbon sinks/sources distribution are an important prerequisite for comprehensively understanding the global carbon cycle and correctly predicting future climate change.Satellite remote sensing is the only method to achieve this monitoring with high resolution.Although spaceborne hyperspectral remote sensing sensors have been successfully applied to monitor the concentration of C02 in the upper troposphere,they are not sensitive to changes in C02 concentrations near the Earth's surface.W让h the rapid development of sensor technology,quantitative remote sensing algorithms,satellites equipped with near-infrared and short-wave infrared hyperspectral sensors dedicated to C02 monitoring have been successively launched. 展开更多
关键词 TanSat a NEW STAR in GLOBAL CARBON MONITORING China
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Mapping the permafrost stability on the Tibetan Plateau for 2005–2015 被引量:17
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作者 youhua ran Xin LI +8 位作者 Guodong CHENG Zhuotong NAN Jinxing CHE Yu SHENG Qingbai WU Huijun JIN Dongliang LUO Zhiguang TANG Xiaobo WU 《Science China Earth Sciences》 SCIE EI CSCD 2021年第1期62-79,共18页
Data scarcity is a major obstacle for high-resolution mapping of permafrost on the Tibetan Plateau(TP).This study produces a new permafrost stability distribution map for the 2010 s(2005–2015)derived from the predict... Data scarcity is a major obstacle for high-resolution mapping of permafrost on the Tibetan Plateau(TP).This study produces a new permafrost stability distribution map for the 2010 s(2005–2015)derived from the predicted mean annual ground temperature(MAGT)at a depth of zero annual amplitude(10–25 m)by integrating remotely sensed freezing degree-days and thawing degree-days,snow cover days,leaf area index,soil bulk density,high-accuracy soil moisture data,and in situ MAGT measurements from 237 boreholes on the TP by using an ensemble learning method that employs a support vector regression model based on distance-blocked resampled training data with 200 repetitions.Validation of the new permafrost map indicates that it is probably the most accurate of all currently available maps.This map shows that the total area of permafrost on the TP,excluding glaciers and lakes,is approximately 115.02(105.47–129.59)×10^4 km^2.The areas corresponding to the very stable,stable,semi-stable,transitional,and unstable types are 0.86×10^4,9.62×10^4,38.45×10^4,42.29×10^4,and 23.80×10^4 km^2,respectively.This new map is of fundamental importance for engineering planning and design,ecosystem management,and evaluation of the permafrost change in the future on the TP as a baseline. 展开更多
关键词 Mountain permafrost Third Pole Remote sensing Statistical learning
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Toward an improved data stewardship and service for environmental and ecological science data in West China 被引量:11
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作者 Xin Li Zhuotong Nan +8 位作者 Guodong Cheng Yongjian Ding Lizong Wu Liangxu Wang Jian Wang youhua ran Hongxing Li Xiaoduo Pan Zhongming Zhu 《International Journal of Digital Earth》 SCIE 2011年第4期347-359,共13页
Sharing of scientific data can help scientific research to flourish and facilitate more widespread use of scientific data for the benefit of society.The Environmental and Ecological Science Data Center for West China... Sharing of scientific data can help scientific research to flourish and facilitate more widespread use of scientific data for the benefit of society.The Environmental and Ecological Science Data Center for West China(WestDC),sponsored by the National Natural Science Foundation of China(NSFC),aims to collect,manage,integrate,and disseminate environmental and ecological data from western China.It also aims to provide a long-term data service for multidisciplinary research within NSFC’s‘‘Environment and Ecology of West China Research Plan’’(NSFC West Plan).An integrated platform has been developed by the WestDC,and this has the function of data sharing,acting as a knowledge repository.Major data sets developed by the WestDC include basic geographic data,the regionalization of global data set for China,scientific data for cold and arid regions in China,scientific data for the cryosphere in countries that neighbor China,data relating to the inland river basins in northwestern China,and data submitted by the NSFC West Plan projects.In compliance with the‘‘full and open’’data sharing policy,most data in the WestDC can be accessed online.Highlights include detailed data documentation,the integration of data with bibliographic knowledge,data publishing,and data reference. 展开更多
关键词 data center West China ECOLOGY environmental science data sharing digital infrastructure
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Investigate the relationships between the Aral Sea shrinkage and the expansion of cropland and reservoir in its drainage basins between 2000 and 2020 被引量:2
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作者 Qiang Li Xin Li +4 位作者 youhua ran Min Feng Yanyun Nian Meibao Tan Xi Chen 《International Journal of Digital Earth》 SCIE 2021年第6期661-677,共17页
The Aral Sea crisis is considered one of the most severe ecological tragedies from the 1960s in Central Asia.The reasons for this crisis,especially in the twenty-first century,are still scientific disputes.This study ... The Aral Sea crisis is considered one of the most severe ecological tragedies from the 1960s in Central Asia.The reasons for this crisis,especially in the twenty-first century,are still scientific disputes.This study investigated the relationship between land cover change in the Aral Sea related basins and the Aral Sea crisis from 2000 to 2020 by employing the GlobeLand30 dataset with 30 m resolution.Results showed that the cultivated land in the Aral Sea basin increased by 2,291 km^(2),and 75.4%of it occurred in the region of Karakum Canal,the largest water conservancy project for irrigation in the world.The water surface area of reservoirs increased by 1,183.5 km^(2) during the same period.Coincident with this change,the Aral Sea further shrank from 26,280.8 km^(2) in 2000 to 9,285.2 km^(2) in 2020,mainly occurred in the first decade of the twenty-first century.These imply that the Aral Sea crisis is persistent in the twenty-first century and is likely driven by water competition among different regions within the basin for agricultural irrigation.Strengthening the coordination and cooperation of crossboundary water resource management is still the most important management strategy choice to address the crisis from a broader perspective. 展开更多
关键词 Aral Sea Karakum Canal water resource management endorheic river basins remote sensing
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Terrestrial carbon cycle model-data fusion:Progress and challenges 被引量:1
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作者 Xin LI Hanqing MA +6 位作者 youhua ran Xufeng WANG Gaofeng ZHU Feng LIU Honglin HE Zhen ZHANG Chunlin HUANG 《Science China Earth Sciences》 SCIE EI CSCD 2021年第10期1645-1657,共13页
The terrestrial carbon cycle is an important component of global biogeochemical cycling and is closely related to human well-being and sustainable development.However,large uncertainties exist in carbon cycle simulati... The terrestrial carbon cycle is an important component of global biogeochemical cycling and is closely related to human well-being and sustainable development.However,large uncertainties exist in carbon cycle simulations and observations.Model-data fusion is a powerful technique that combines models and observational data to minimize the uncertainties in terrestrial carbon cycle estimation.In this paper,we comprehensively overview the sources and characteristics of the uncertainties in terrestrial carbon cycle models and observations.We present the mathematical principles of two model-data fusion methods,i.e.,data assimilation and parameter estimation,both of which essentially achieve the optimal fusion of a model with observational data while considering the respective errors in the model and in the observations.Based upon reviewing the progress in carbon cycle models and observation techniques in recent years,we have highlighted the major challenges in terrestrial carbon cycle model-data fusion research,such as the“equifinality”of models,the identifiability of model parameters,the estimation of representativeness errors in surface fluxes and remote sensing observations,the potential role of the posterior probability distribution of parameters obtained from sensitivity analysis in determining the error covariance matrixes of the models,and opportunities that emerge by assimilating new remote sensing observations,such as solar-induced chlorophyll fluorescence.It is also noted that the synthesis of multisource observations into a coherent carbon data assimilation system is by no means an easy task,yet a breakthrough in this bottleneck is a prerequisite for the development of a new generation of global carbon data assimilation systems.This article also highlights the importance of carbon cycle data assimilation systems to generate reliable and physically consistent terrestrial carbon cycle reanalysis data products with high spatial resolution and longterm time series.These products are critical to the accurate estimation of carbon cycles at the global and regional scales and will help future carbon management strategies meet the goals of carbon neutrality. 展开更多
关键词 Carbon cycle Model-data fusion Data assimilation Parameter estimation Remote sensing UNCERTAINTY
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