陕北黄土丘陵区主要作物需水量变化趋势及其应对策略OA北大核心CSTPCD

[Objective]The aims of this study are to investigate the historical and future trends of drought,precipitation,and the water requirement of major crops,to gain insights into the evolving characteristics of meteorological drought and the water balance for key crops in the loess hilly region of northern Shaanxi,and to provide the reference for implementing effective irrigation practices and optimizing crop cultivation in this region.[Method]The daily-scale basic meteorological data from the loess hilly region of northern Shaanxi for the period 1980 to 2017 were utilized.The Mann-Kendall method with pre-whitening and the R/S method were employed to analyze the trend changes in drought,precipitation,and crop water requirement during the crop growing season(April to October)in past and future.[Results](1)Drought showed a decreasing trend from April to June and an increasing trend from July to October.The variation in effective precipitation exhibited different patterns across the months and regions.Crop water requirement showed an increasing trend from April to August.(2)In the future,the effective precipitation in May,July,and October is projected to decrease,while the effective precipitation in August and September will experience an increasing trend.Drought and crop water requirement in Yan'an will exhibit opposite trends from April to June compared to that in Yulin.[Conclusion]The frequent droughts occur,and the available precipitation is insufficient to meet crop water requirements in the Loess Plateau of northern Shaanxi.The measures to control the cultivation area of jujube and apples,to increase investment in millet cultivation,and to implement a combination of rainwater harvesting and mulching are suggested in order to meet crop water requirements,achieve higher yields and increase income.