Response of drought index to land use types in the Loess Plateau of Shaanxi, China

From 1980 to 2010, the types of land use in the Loess Plateau region of Shaanxi changed, which is affected the changes of drought. To study the impact of reform and opening up and the project of returning farmland to forests on drought in the study area, the drought index SPI of 8 stations was obtained on the basis of the meteorological and land use data of the study area from 1980 to 2010. From the perspective of various land-use types, based on univariate linear regression, the time envelope is divided into five periods, and the impacts of different land-use types on drought are analyzed one by one. From 1980 to 2010, the outcomes showed that the drought intensity of forest was the largest, the arable land is the second largest and town and country is final. However, arable land had the greatest response to drought index, followed by town and country, and forest had the weakest response to drought index. From 2000 to 2010, the drought intensity of the forest was the largest, followed by town and country and arable land. Also, drought index has the strongest response to the forest, the second is town and country, the arable land is final. The area of forest, grass and town and country is increasing, the proportion of arable land cuts down year by year, and the types of land use are constantly undergoing complex changes. The drought index has a strong response to the change of arable land to grass and arable land to town and country, but has a weak response to the mutual transformation of grass and town and country.