Monitoring Spatiotemporal Dynamic of Drought in Shendong Mining Area Based on Temperature Vegetation Dryness Index

【Objective】 Drought is a stress that crops often experience during their growing season, and comprehending its spatiotemporal dynamics in a region is important to improve agricultural management. In this paper, we propose to predict drought using temperature vegetation dryness index (TDVI). 【Method】 The studied site was a mining area in Shendong, Shandong province. We acquired 36 Landsat images during the growing seasons from 1991 to 2018. The TVDI calculated from these images was used to estimate the spatiotemporal dynamic of drought for different vegetations using mathematical statistical analysis methods, including deviation analysis, linear tendency analysis and spatial transfer matrix. 【Result】 ①Intra-annually, the value of TVDI was low from June to September; overall, the UF~UB curve was less than 0, and the TVDI exhibited a decreasing trend. Inter-annually, the value of TVDI was greater than 0 in 1991, 2002, 2007 and 2010, and showed an increasing trend from 1991 to 2010. The deviation value of TVDI was less than 0 in 2014 and 2018 and showed a decreasing trend from 2010 to 2018. ②Spatially, the value of TVDI was high in the southwest and low in the northeast, and the areas that experienced drought had declined from 1991—2010. ③Trend analysis showed that the areas where the TVDI had decreased from 1991—2010 was larger than the areas where the TVDI had increased. The areas where the TVDI had decreased were 2 394.74 km2 at the most, while the areas where the TVDI had increased were 425.91 km2 at the least. ④Majority of the studied region has undergone a transition from relatively dry state to normal or wet state, and the transition in the opposite direction is less extensive. 【Conclusion】 Using TVDI calculated from satellite images to monitor spatiotemporal dynamics of drought in the mining area in Shendong is accurate and robust. Our findings have important implication for help land reclamation in mining areas.