Abstract: To understand the agricultural drought situation and its influencing factors in Gansu Province, the feature space was constructed by Normalized Difference Vegetation Index and Land Surface Temperature. Temperature Vegetation Dryness Index (TVDI) was calculated to evaluate the drought event during 2001-2016, and its influencing factors were quantitatively analyzed. Drought occurred every year in Gansu, with the proportion of lightly and moderately dry acreage being largest. Drought had obvious regional differentiation in space, gradually increased from southeast to northwest. The drought was heavy in most parts of Hexi Corridor and rarely occurred in Qilian Mountains and Gannan plateau. The formation of drought and non-drought occurrence regions was the result of a combination of many factors such as altitude, temperature, precipitation, underlying surface, and human disturbance. Large acreage of drought usually occurred in regions with lower altitude, higher temperature, less precipitation, sparse vegetation and land types dominated by sand and Gobi. Temperature, precipitation, altitude, slope, vegetation types and land cover types were the major factors influencing agricultural drought. Other factors were superimposed together with major factors, resulting in the overall pattern of “southeast wet and northwest drought” in Gansu. Using TVDI index based on the combination of vegetation and temperature to reflect agricultural drought situation, it is simple in calculation and its results are scientific and accurate. This method is worth to be tried and used in drought monitoring of meteorological department in the future. Our results provide scientific reference for preventing drought and formulating agricultural production policies.

Key words: yield, nutrient uptake, gravel-mulched field, watermelon, organic fertilizer, quality