塔里木河流域面临植被退化、土地荒漠化等生态问题,为解决这一问题,需要开展荒漠化敏感性评估。采用遥感、全球定位系统和地理信息系统,构建土壤、植被、气候和管理质量等指标定量评估,利用地中海荒漠化与土地利用(Mediterranean Desert...塔里木河流域面临植被退化、土地荒漠化等生态问题,为解决这一问题,需要开展荒漠化敏感性评估。采用遥感、全球定位系统和地理信息系统,构建土壤、植被、气候和管理质量等指标定量评估,利用地中海荒漠化与土地利用(Mediterranean Desertification and Land Use,MEDALUS)模型计算敏感性指数获取荒漠化敏感区,在此基础上分析荒漠化敏感性的驱动因素。结果表明,塔里木河流域属于极高敏感区。荒漠化敏感性的空间格局是中部高、北部低,主要由与人类活动有关的管理质量指数决定。从绿洲内至绿洲外,荒漠化敏感性逐渐升高,大致呈层状分布,表明人类活动对荒漠化影响显著,建议加强和巩固绿洲外围的防护体系建设。展开更多
Xinjiang Uygur Autonomous Region is a typical inland arid area in China with a sparse and uneven distribution of meteorological stations,limited access to precipitation data,and significant water scarcity.Evaluating a...Xinjiang Uygur Autonomous Region is a typical inland arid area in China with a sparse and uneven distribution of meteorological stations,limited access to precipitation data,and significant water scarcity.Evaluating and integrating precipitation datasets from different sources to accurately characterize precipitation patterns has become a challenge to provide more accurate and alternative precipitation information for the region,which can even improve the performance of hydrological modelling.This study evaluated the applicability of widely used five satellite-based precipitation products(Climate Hazards Group InfraRed Precipitation with Station(CHIRPS),China Meteorological Forcing Dataset(CMFD),Climate Prediction Center morphing method(CMORPH),Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record(PERSIANN-CDR),and Tropical Rainfall Measuring Mission Multi-satellite Precipitation Analysis(TMPA))and a reanalysis precipitation dataset(ECMWF Reanalysis v5-Land Dataset(ERA5-Land))in Xinjiang using ground-based observational precipitation data from a limited number of meteorological stations.Based on this assessment,we proposed a framework that integrated different precipitation datasets with varying spatial resolutions using a dynamic Bayesian model averaging(DBMA)approach,the expectation-maximization method,and the ordinary Kriging interpolation method.The daily precipitation data merged using the DBMA approach exhibited distinct spatiotemporal variability,with an outstanding performance,as indicated by low root mean square error(RMSE=1.40 mm/d)and high Person's correlation coefficient(CC=0.67).Compared with the traditional simple model averaging(SMA)and individual product data,although the DBMA-fused precipitation data were slightly lower than the best precipitation product(CMFD),the overall performance of DBMA was more robust.The error analysis between DBMA-fused precipitation dataset and the more advanced Integrated Multi-satellite Retrievals for Global Precipitation Measurement Final(IMERG-F)precipitation product,as well as hydrological simulations in the Ebinur Lake Basin,further demonstrated the superior performance of DBMA-fused precipitation dataset in the entire Xinjiang region.The proposed framework for solving the fusion problem of multi-source precipitation data with different spatial resolutions is feasible for application in inland arid areas,and aids in obtaining more accurate regional hydrological information and improving regional water resources management capabilities and meteorological research in these regions.展开更多
生态系统水分利用效率(water use efficiency,WUE)是碳水循环中的重要参数。全球干旱在未来几十年将会持续增加,干旱对生态系统WUE的影响研究成为了区域及全球尺度上的研究热点与难点。该文研究中亚地区生态系统WUE对干旱的响应。以中亚...生态系统水分利用效率(water use efficiency,WUE)是碳水循环中的重要参数。全球干旱在未来几十年将会持续增加,干旱对生态系统WUE的影响研究成为了区域及全球尺度上的研究热点与难点。该文研究中亚地区生态系统WUE对干旱的响应。以中亚5国及中国新疆为研究区,利用基于中分辨率成像光谱仪的总初级生产力产品和蒸散产品计算2000—2014年生态系统尺度上的WUE,使用归一化植被指数和陆地表面温度计算温度植被干旱指数分析干旱区生态系统WUE与干旱的关系。结果表明,WUE对干旱的响应在不同地区和植被类型中表现出一定的差异;当干旱发生时,干旱区生态系统WUE对干旱通常表现出负面响应,同时干旱对生态系统WUE有滞后影响;干旱事件结束后,生态系统WUE与干旱指数呈现正相关关系;另外,干旱区生态系统WUE对干湿环境突变敏感,当环境从干旱转向湿润,郁闭灌木林,农田,森林,草地,稀疏灌木林WUE分别增加了30.03%,49.57%,18.39%,54.71%,49.28%,WUE的快速增长表明了干旱区生态系统有较强的恢复力稳定性。展开更多
在SWAT(soil and water assessment tool)模型模拟地表分量过程中,常默认土壤剖面电导率(electrical conductivity,EC)值为0或0.1,将其应用于土壤盐渍化程度较高的流域时,不符合下垫面实际情况。为确保水文模拟逼近真实地表模拟过程,进...在SWAT(soil and water assessment tool)模型模拟地表分量过程中,常默认土壤剖面电导率(electrical conductivity,EC)值为0或0.1,将其应用于土壤盐渍化程度较高的流域时,不符合下垫面实际情况。为确保水文模拟逼近真实地表模拟过程,进一步提高模拟精度,该文利用GF-1号卫星16 m分辨率多光谱遥感影像结合分类回归树法反演艾比湖流域区域尺度0~100 cm土壤剖面电导率,模拟值与实测值均方根最大值误差为4.81 dS/m,相对误差最大值为15.17%。模拟值用于修正EC值,结果表明:EC值修正后的SWAT模型土壤水分模拟值,较修正前模拟值精度提高23.84个百分点。该方法在实现SWAT模型参数本地化的同时,有效提高了土壤水分模拟精度,可为土壤盐渍化区域水文模拟提供参考。展开更多
文摘塔里木河流域面临植被退化、土地荒漠化等生态问题,为解决这一问题,需要开展荒漠化敏感性评估。采用遥感、全球定位系统和地理信息系统,构建土壤、植被、气候和管理质量等指标定量评估,利用地中海荒漠化与土地利用(Mediterranean Desertification and Land Use,MEDALUS)模型计算敏感性指数获取荒漠化敏感区,在此基础上分析荒漠化敏感性的驱动因素。结果表明,塔里木河流域属于极高敏感区。荒漠化敏感性的空间格局是中部高、北部低,主要由与人类活动有关的管理质量指数决定。从绿洲内至绿洲外,荒漠化敏感性逐渐升高,大致呈层状分布,表明人类活动对荒漠化影响显著,建议加强和巩固绿洲外围的防护体系建设。
基金supported by The Technology Innovation Team(Tianshan Innovation Team),Innovative Team for Efficient Utilization of Water Resources in Arid Regions(2022TSYCTD0001)the National Natural Science Foundation of China(42171269)the Xinjiang Academician Workstation Cooperative Research Project(2020.B-001).
文摘Xinjiang Uygur Autonomous Region is a typical inland arid area in China with a sparse and uneven distribution of meteorological stations,limited access to precipitation data,and significant water scarcity.Evaluating and integrating precipitation datasets from different sources to accurately characterize precipitation patterns has become a challenge to provide more accurate and alternative precipitation information for the region,which can even improve the performance of hydrological modelling.This study evaluated the applicability of widely used five satellite-based precipitation products(Climate Hazards Group InfraRed Precipitation with Station(CHIRPS),China Meteorological Forcing Dataset(CMFD),Climate Prediction Center morphing method(CMORPH),Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record(PERSIANN-CDR),and Tropical Rainfall Measuring Mission Multi-satellite Precipitation Analysis(TMPA))and a reanalysis precipitation dataset(ECMWF Reanalysis v5-Land Dataset(ERA5-Land))in Xinjiang using ground-based observational precipitation data from a limited number of meteorological stations.Based on this assessment,we proposed a framework that integrated different precipitation datasets with varying spatial resolutions using a dynamic Bayesian model averaging(DBMA)approach,the expectation-maximization method,and the ordinary Kriging interpolation method.The daily precipitation data merged using the DBMA approach exhibited distinct spatiotemporal variability,with an outstanding performance,as indicated by low root mean square error(RMSE=1.40 mm/d)and high Person's correlation coefficient(CC=0.67).Compared with the traditional simple model averaging(SMA)and individual product data,although the DBMA-fused precipitation data were slightly lower than the best precipitation product(CMFD),the overall performance of DBMA was more robust.The error analysis between DBMA-fused precipitation dataset and the more advanced Integrated Multi-satellite Retrievals for Global Precipitation Measurement Final(IMERG-F)precipitation product,as well as hydrological simulations in the Ebinur Lake Basin,further demonstrated the superior performance of DBMA-fused precipitation dataset in the entire Xinjiang region.The proposed framework for solving the fusion problem of multi-source precipitation data with different spatial resolutions is feasible for application in inland arid areas,and aids in obtaining more accurate regional hydrological information and improving regional water resources management capabilities and meteorological research in these regions.
文摘生态系统水分利用效率(water use efficiency,WUE)是碳水循环中的重要参数。全球干旱在未来几十年将会持续增加,干旱对生态系统WUE的影响研究成为了区域及全球尺度上的研究热点与难点。该文研究中亚地区生态系统WUE对干旱的响应。以中亚5国及中国新疆为研究区,利用基于中分辨率成像光谱仪的总初级生产力产品和蒸散产品计算2000—2014年生态系统尺度上的WUE,使用归一化植被指数和陆地表面温度计算温度植被干旱指数分析干旱区生态系统WUE与干旱的关系。结果表明,WUE对干旱的响应在不同地区和植被类型中表现出一定的差异;当干旱发生时,干旱区生态系统WUE对干旱通常表现出负面响应,同时干旱对生态系统WUE有滞后影响;干旱事件结束后,生态系统WUE与干旱指数呈现正相关关系;另外,干旱区生态系统WUE对干湿环境突变敏感,当环境从干旱转向湿润,郁闭灌木林,农田,森林,草地,稀疏灌木林WUE分别增加了30.03%,49.57%,18.39%,54.71%,49.28%,WUE的快速增长表明了干旱区生态系统有较强的恢复力稳定性。
文摘在SWAT(soil and water assessment tool)模型模拟地表分量过程中,常默认土壤剖面电导率(electrical conductivity,EC)值为0或0.1,将其应用于土壤盐渍化程度较高的流域时,不符合下垫面实际情况。为确保水文模拟逼近真实地表模拟过程,进一步提高模拟精度,该文利用GF-1号卫星16 m分辨率多光谱遥感影像结合分类回归树法反演艾比湖流域区域尺度0~100 cm土壤剖面电导率,模拟值与实测值均方根最大值误差为4.81 dS/m,相对误差最大值为15.17%。模拟值用于修正EC值,结果表明:EC值修正后的SWAT模型土壤水分模拟值,较修正前模拟值精度提高23.84个百分点。该方法在实现SWAT模型参数本地化的同时,有效提高了土壤水分模拟精度,可为土壤盐渍化区域水文模拟提供参考。
