基于植被状态指数的陕西省农业干旱时空动态  

Assessment of temporal and spatial dynamics of agricultural drought in Shaanxi Province based on vegetation condition index

作　　者：李新尧 杨联安[1,2] 聂红梅 任丽 胡胜[1,2] 杨煜岑[1,2] LI Xin-yao1,2, YANG Lian-an1,2, NIE Hong-mei1,2, HEN Li1,2, HU Sheng1,2, YANG Yu-een1,2(1 Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, Northwest University, Xi＇ an 710127, China; 2College of Urban and Environmental Sciences, Northwest University, Xi＇ an 710127, China)

机构地区：[1]西北大学陕西省地表系统与环境承载力重点实验室,西安710127 [2]西北大学城市与环境学院,西安710127

出　　处：《生态学杂志》2018年第4期1172-1180,共9页Chinese Journal of Ecology

基　　金：教育部人文社会科学研究规划项目(10YJA910010);陕西省农业科技攻关项目(2011K02-11);西安市科技计划农业技术研发项目(NC150201和NC1402);西北大学研究生自主创新项目(YZZ17151和YZZ17147)资助

摘　　要：特殊的地理位置和气候类型决定了陕西省是旱灾多发区和重发区,利用遥感技术进行高效的农业干旱监测和旱情影响分析显得十分必要。本文以植被状态指数(VCI)作为农业生长季节干旱监测指标,探讨了VCI在陕西省农业干旱监测中的适用性以及与降水的相关性,并利用VCI对陕西省2002年3月—2016年5月农业干旱进行识别与时空分布特征研究。结果表明:VCI指数在监测陕西省农业干旱方面具有一定的优势;月尺度VCI与降水量并未表现出很好的相关性,表明降水只是影响植被覆盖度和长势的因素之一;VCI相对于降水变化存在一定时间的滞后性,其中关中和陕南地区约为1个月,陕北地区小于1个月;近15年来,陕西省全域性农业干旱事件多发生在3月,其次为10月和11月,连续性农业干旱多发生在春季或秋季,其总体干旱状况有所减轻;秋季农业干旱面积占比最大,频率最高;夏季农业干旱面积占比最小,频率最低;春季农业干旱面积处于夏季和秋季之间;空间分布上,陕北大部分区域易发生春旱和秋旱,关中和陕南仅局部地区发生春旱和秋旱,农业干旱频率总体上呈现北高南低的态势。Drought is frequent and severe in Shaanxi Province because of the special geographical location and climate. Thus, it is critically needed for efficient agricultural drought monitoring and drought impact analysis using remote sensing technology. Here, we used vegetation conditionindex （VCI） as the monitoring indicator of agricultural drought at growing season to explore the applicability of VCI in agricultural drought monitoring in Shaanxi Province and its correlation with precipitation. Then VCI was adopted to identify and analyze the temporal and spatial dynamics of agricultural drought from March 2002 to May 2016. The results showed that VCI had some advantages in monitoring agricultural drought in Shaanxi Province. VCI did not show good correlation with precipitation on monthly scale, which indicated that precipitation was just one of many factors affecting vegetation coverage and growth. VCI had lag response to precipitation change, with about one month lag in Guanzhong plain and southern Shaanxi, less than one month lag in northern Shaanxi. Over the past fifteen years, agricultural drought events of Shaanxi Province mainly occurred in March, followed by October and November. While continuous agricultural droughts mainly occurred in spring or autumn, the overall drought condition had been alleviated. Theproportion of drought area was the largest in autumn and smallest in summer. The droughtfrequency was the highest in autumn and lowest in summer. Most of the region in northern Shaanxi was prone to spring drought and autumn drought, while some areas of Guanzhong plain and southern Shaanxi were prone to spring drought and autumn drought. The drought frequency was the highest in northern Shaanxi, followed by Guanzhong plain and lowest in southern Shaanxi.

关 键 词：植被状态指数(VCI) 农业干旱 时空动态 陕西省 

分 类 号：S423[农业科学—植物保护]