近40年(1982年—2018年)中国草原区干湿变化趋势分析  

Spatial and temporal variation characteristics of the drought index in China grasslands in the recent 40 years(1982—2018)

作　　者：底凯 胡中民 郝珖存 曹若臣 梁敏琪 韩道瑞 吴戈男[4,5] DI Kai;HU Zhongmin;HAO Guangcun;CAO Ruochen;LIANG Minqi;HAN Daorui;WU Genan(School of Geography,South China Normal University,Guangzhou 510631,China;CCCC Fourth Harbor Engineering Institute Co.,Ltd,Guangzhou 510230,China;Key Laboratory of Environmental Protection&Safety of Communication Foundation Engineering,CCCC,Guangzhou 510230,China;Synthesis Research Center of Chinese Ecosystem Research Network,Key Laboratory of Ecosystem Network Observation and Modeling,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China;College of Resources and Environment,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]华南师范大学地理科学学院,广州510631 [2]中交四航工程研究院有限公司,广州510230 [3]中交交通基础工程环保与安全重点实验室,广州510230 [4]中国科学院地理科学与资源研究所生态系统观测与模拟重点实验室,北京100101 [5]中国科学院大学资源与环境学院,北京100049

出　　处：《遥感学报》2022年第12期2629-2641,共13页NATIONAL REMOTE SENSING BULLETIN

基　　金：国家重点研发计划(编号:2017YFA0604801);国家自然科学基金(编号:31922053,32001142)。

摘　　要：在全球变暖影响下,由降水、气温等气象要素所主导的干湿条件在全球或区域上均发生了明显变化,中国草原区对气候变化敏感、具有明显的生态脆弱性特征,因此研究中国草原区的干湿变化趋势非常重要。本研究基于干旱指数分析了1982年—2018年中国草原区的干湿程度时空变化趋势。结果表明,1982年—2018年中国草原区的干旱指数呈不显著上升趋势。2005年前后两个时期中国草原区表现出显著的趋势差异,1982年—2005年中国草原区干旱指数呈下降趋势,即干旱程度增加,而2006年—2018年呈增加趋势,该时段湿润化明显。2006年之后的中国草原区湿润化趋势源于该地区降水持续增多,而增温停滞导致潜在蒸散发不再升高。分区域来看,1982年—2005年内蒙古草原区干旱指数呈下降趋势,2006年—2018年呈上升趋势;西北草原区在1982年—2005年和2006年—2018年两个时间段干旱指数均呈上升趋势;青藏草原区在1982年—1994年干旱指数呈下降趋势,1995年—2018年呈上升趋势。The dry/wet conditions dominated by precipitation,air temperature,and other meteorological factors have globally or regionally changed as a result of global warming.Grasslands cover around 40% of China and are vulnerable to climate change and ecological susceptibility.Accordingly,the dry/wet condition change trend of grasslands in China must be studied.Many studies on drought have been conducted in China,but two defects continue to persist:(1) most studies did not take into account the dry and wet changes of grassland in China as a whole;(2) the time range of research has not been extended to recent years.This study analyzed the temporal variation of drought-wet degree and its causes in this region during 1982—2018 based on the drought index and meteorological factors.The optimal drought index is the maximum correlation coefficient of soil moisture and multi drought index,and the optimal drought index was used for subsequent analysis.The piecewise regression approach was used to examine whether a turning point of the trend of drought index developed,and ordinary least squares was used to test the significance.The least square method was used to estimate the trend of the drought index.Pearson correlation analyses were conducted to quantify the relationship between drought index and climatic factors.Our results indicated the drought index based on the station ratio of precipitation and GLEAM potential evapotranspiration,which can reflect the change of dry/wet degree in China’s grasslands.The drought index had no significant increase trend from 1982 to 2018,and a trend shift occurred in 2005.The drought index of grasslands in China decreased by-0.0005 a-1 from 1982 to 2005 and increased by 0.009 a-1 from 2006 to 2018.The reason is that the increased water consumption causes increased the temperature and enhanced the evapotranspiration from 1982 to 2005.The water consumption of evapotranspiration was alleviated from 2006 to 2018 due to the continuous increase in precipitation and stagnation of temperature increas

关 键 词：遥感 中国草原区 干旱指数 动态变化 转变 气候变化 

分 类 号：P2[天文地球—测绘科学与技术]