【摘要】 为了能够利用卫星遥感数据对不同年份冬小麦受旱状况进行客观定量的评价,以甘肃陇东雨养农业区为研究区域,应用1981-2006年NASA GIMMS NDVI数据以及同期的降水、土壤水分和冬小麦产量数据,通过研究25个冬小麦生长季NDVI(Normalized Difference Vegetation Index)特征以及与降水、土壤水分和生育期的相互联系,提出了能对冬小麦全生育期受旱状况进行客观定量评价的冬小麦受旱指数WWDI(Winter wheat drought index),并根据气象数据、冬小麦产量和历史年鉴资料对WWDI监测的冬小麦受旱状况的准确性进行检验。结果表明:WWDI能够很好地监测冬小麦的全生育期的受旱状况,应用WWDI确定的1981-2006年间冬小麦受旱最严重的几个年份分别是1995,2000和1992年,这几年冬小麦的受旱程度与其气象条件和农业生产状况非常一致; WWDI与冬小麦产量存在极显著的相关关系(p<0. 001),可以作为定量评估冬小麦整个生育期受旱状况的指标。更多还原

【Abstract】 Drought is a widespread climate phenomenon throughout the world,as well as one of the natural disasters that seriously impact agricultural. The frequency,intensity and impact of drought are increasing with the global warming,which bring severe challenges to food and ecological security. It is significant for global food and ecological security and sustainable development to strengthen the research and development of drought monitoring and assessment technology to improve the level of drought monitoring and early drought warning. Satellite remote sensing technology can obtain drought information widely,quickly and dynamically; Meanwhile it can cover the shortage of discontinuous and point-to-area of discrete ground sites monitoring space on the ground effectively. In this paper,we select the Longdong rain-fed agricultural area with precipitation of 400 ～ 600 mm in the semi-humid climate area in Gansu Province,Northwest China,to evaluate the drought situation of winter wheat in different years using satellite remote sensing data objectively and quantitatively. Based on NASA GIMMS NDVI data from 1981 to 2006 together with precipitation,soil moisture and winter wheat yield data of the same period,the characteristics of winter wheat NDVI and the relationship with precipitation,soil moisture and growth period in these 25 years were analyzed. Furthermore,a new index WWDI( Winter Wheat Drought Index) is proposed,which can objectively and quantitatively evaluate the winter wheat drought situation during the whole growth period. This index considers the slow development of drought and the gradual accumulation of impacts on crops,and implies the robustness of crop growth. The accuracy of WWDI was tested use meteorological data,winter wheat yield and historical Yearbook data. The results showed that:( 1) The WWDI can monitor the drought degree of winter wheat during whole growth period. 1995,2000 and 1992 were the worst drought years that winter wheat suffered in the study area,and the drought degree of winter wheat was corresponding with its meteorological conditions and actual agricultural production.( 2) The WWDI has a very significant correlation with winter wheat yield( p<0. 001) and WWDI can be used as an index to evaluate quantitatively the drought status of winter wheat during the whole growth period.更多还原