喀斯特地区不同时间尺度农业干旱对局地气候因子脉冲响应机制  

Impulse Response Mechanism of Agricultural Drought to Local Climate Factor at Different Time Scales in Karst Region

作　　者：余欢 贺中华[1,2,3] 顾小林 许明金 谭红梅 杨树平 杨秋云 YU Huan;HE Zhonghua;GU Xiaolin;XU Mingjin;TAN Hongmei;YANG Shuping;YANG Qiuyun(College of Geography and Environmental Science,Guizhou Normal University,Guiyang 550001,China;National Engineering Research Center for Karst Rocky Desertification Control,Guizhou Normal University,Guiyang 550001,China;Guizhou Provincial Key Laboratory of Remote Sensing Application of Mountain Resources and Environment,Guiyang 550001,China;Guizhou Bureau of Hydrology and Water Resources,Guiyang 550000,China)

机构地区：[1]贵州师范大学地理与环境科学学院,贵阳550001 [2]贵州师范大学国家喀斯特石漠化防治工程技术研究中心,贵阳550001 [3]贵州省山地资源与环境遥感应用重点实验室,贵阳550001 [4]贵州省水文水资源局,贵阳550000

出　　处：《水土保持学报》2024年第5期296-304,共9页Journal of Soil and Water Conservation

基　　金：国家自然科学基金项目(u1612441,41471032);贵州省水利厅自然科学基金项目(KT202237);贵州省自然科学基金项目(黔科合基础-ZK[2023]重点028)。

摘　　要：[目的]为定量解析喀斯特地区农业干旱对单因子的响应机制。[方法]利用泰森多边形及K阶均值聚类对贵州省83个站点年平均降雨量进行面积计算及分类,将贵州省划分为5个区域,并基于各分区降雨量(Pre)、平均气温(T)、潜在蒸散发(E)、风速(W)、气压(P)、土壤水分(SW)、标准化土壤水分指数(SSI)建立向量自回归(VAR)模型,通过脉冲响应与方差分解分析不同时间尺度农业干旱对各气象因子及土壤水分含量的响应机制。[结果](1)农业干旱呈现西高东低,总体由南往北逐渐减轻;春、夏季农业干旱强于秋冬季。(2)年尺度各因子对SSI脉冲响应达峰值所需时间为Pre<E=W<P<SW<T,恢复平稳期则为Pre>W>T>E>P>SW。由月尺度到年尺度,岩溶发育较强区域E对SSI脉冲达峰值所需时间缩短2期;SW与之相反,且非岩溶地区比岩溶地区恢复平稳期短。(3)降雨量在农业干旱中占主导地位,降雨与风速随时间尺度增加在农业干旱中作用增强,其农业干旱贡献比例月、季、年分别为31.88%,34.25%,58.33%和1.07%,3.15%,12.88%。[结论]研究成果可为喀斯特地区农业干旱预警提供参考理论依据。[Objective]In order to quantitatively analyze the response mechanism of agricultural drought to single factor in karst areas.[Methods]In this study,Delaunay triangulation and K-means clustering were employed to calculate the area and classify the annual rainfall data of 83 stations in Guizhou Province,resulting in the division of Guizhou into 5 regions.Subsequently,a vector autoregressive(VAR)model was established based on the meteorological factors including precipitation(Pre),average temperature(T),potential evapotranspiration(E),wind speed(W),air pressure(P),soil moisture content(SW),and standardized soil moisture index(SSI)for each region.The response mechanism of agricultural drought to various time scales of meteorological factors and soil moisture content was analyzed using pulse response and variance decomposition.[Results](1)The agricultural drought was higher in the west and lower in the east,and gradually decreased from south to north;The agricultural drought is more severe in spring and summer than in autumn and winter.(2)The time required for the impulse response of each variable on the annual scale to reach the peak of SSI is Pre<E=W<P<SW<T,and the recovery period is Pre>W>T>E>P>SW.From the monthly scale to the annual scale,in areas with strong karst development,the time required for SSI pulse to reach its peak value is shortened by 2 periods for factor E;while SW is opposite to this,and the non-karst area has a shorter recovery period than karst area.(3)Rainfall plays a dominant role in agricultural drought,and rainfall and wind speed played a stronger role in agricultural drought with the increase of time scale.The contribution ratio of agricultural drought was 31.88%,34.25%,58.33%,1.07%,3.15%and 12.88%,respectively.[Conclusion]The research results can provide a theoretical basis for the early warning of agricultural drought in karst areas.

关 键 词：农业干旱 气候因子 向量自回归模型 脉冲响应 贵州省 

分 类 号：S423[农业科学—植物保护]