Application of ITVDI Improved by Constraint Line Method to Drought Assessment in Jingzhou City
Drought is an important factor affecting agricultural production and regional sustainable development. Monitoring and analyzing the temporal and spatial characteristics of drought and its driving factors were of great significance for formulating effective response measures. The temperature vegetation drought index (ITVDI) was improved based on the constraint line method,and the MODIS NDVI and LST data from 2001 to 2020 were used to monitor and analyze the drought in Jingzhou City. The results showed that the drought intensity in Jingzhou City had fluctuated and decreased after 2015. Spatial heterogeneity existed in the drought characteristics of Jingzhou City. The drought in the western and eastern areas increased significantly,while the drought in the downtown area decreased significantly. We further identified and quantified the constrained effects of human activities (population,GDP,land use type),climate change (precipitation,temperature) and topography (ele-vation,slope) on drought intensity in Jingzhou City. It was found that these factors had eight constraint effects on drought intensity,including U-shaped curve,positive linear,negative linear,logarithmic,negative convex,positive convex,exponential and hump type. Precipitation and temperature were the most direct factors affecting drought intensity,and they had a constraint effect on the upper and lower boundaries of drought intensity. The constraint effected of altitude,slope,GDP and population on drought intensity were stable in scale. It was worth noting that the constraint effect of land use type on drought intensity was U-shaped,and the minimum threshold value appeared in the area covered by forest land and water. We provided scientific decision support for alleviating regional drought and promoting regional sustainable development,so as to look forward to future research directions and needs.
DroughtTemperatureVegetation drought indexConstraint line methodJingzhou City
万方数据
维普
