基于大豆生长期需水探讨降水资源与干旱风险度

摘要

依据叶柏寿、朝阳气象站1954～2013年大气降水资料和有关研究单位的农作物灌溉试验成果之大豆生育期耗水资料，运用线性趋势变化、干湿指数、干旱风险度分析方法，研究辽西朝阳地区大豆生长期大气降水变化特征以及大豆生育期的干旱特征和干旱风险程度。结果表明：大豆全生育期大气降水呈减少趋势，其中，播种至开花阶段降水呈增加趋势，开花至成熟阶段降水呈减少趋势。大豆全生育期平均缺水为6．1％，全年性干旱占13．3％，平均干旱风险度达到57．6％。播种至出苗缺水7．9％，干旱频率为50．0％；出苗至分枝缺水5．6％，干旱频率为28．3％；分枝至开花降水盈余24．9％，干旱频率为10．0％；开花至鼓粒降水盈余20．8％，干旱频率为16．7％；鼓粒至成熟缺水11．6％，干旱频率为33．3％。辽西朝阳地区降水减少和干旱风险上升趋势对农业生产的影响越来越大，缺水越来越明显。因此开发利用地表水、地下水和云水资源等工程建设，是农作物赢得丰收的基本保证。%According to Yebaishou and Chaoyang weather station’ s precipitation data from 1954 to 2013 and water consumption data during soybean growth period obtained from crop irrigation experiments, the at-mospheric precipitation variation characteristics, drought characteristics and drought risk degree in soybean growth period were studied in Chaoyang area of Liaoning Province by the methods of linear trend variation, dry and wet index, drought risk degree.The results showed that the precipitation had a decreasing trend during the whole growth period of soybean.In which, the precipitation showed an increasing trend from sowing to flowering stage, while that showed a decreasing trend from flowering to mature stage.The average dry ratio was 6.1% during the whole growth period of soybean, and the annual drought ratio was 13.3%.The average drought risk degree was 57.6%.The water shortage ratio and the drought frequency were 7.9%and 50.0%respectively from sowing to seedling emergence, while those were 5.6%and 28.3%respectively from seedling emergence to branching.The precipitation surplus ratio and the drought frequency were 24.9% and 10.0%respectively from branching to blossom, while those were 20.8%and 16.7%respectively from blossom to pod filling.The water shortage ratio was 11.6%, and the drought frequency was 33.3% from pod filling to ma-ture.The precipitation decreasing and drought risk rising trends in Chaoyang area of Liaoning Province had in-creasing influences on agricultural production, and the water shortage was becoming more and more serious.Therefore, the development and utilization of surface water, groundwater, and cloud water resources would be the basic guarantee of crop harvest.