自然降水条件下关中平原农业水资源短缺风险分析  

Risk Analysis of Shortage of Agricultural Water Resources in Guanzhong Plain Under Natural Precipitation

作　　者：卢泽华[1,3] 王君勤 LU Zehua;WANG Junqin(Sichuan Provincial Bureau of Farmland and Water Resources,Chengdu 610015,China;Research Institute of Sichuan Academy of Water Resources,Chengdu 610072,China;College of Water Resource&Hydropower,Sichuan University,Chengdu 610041,China)

机构地区：[1]四川省农田水利局,成都610015 [2]四川省水利科学院研究院,成都610072 [3]四川大学水利水电学院,成都610041

出　　处：《水土保持研究》2021年第6期364-370,共7页Research of Soil and Water Conservation

基　　金：四川省水科院“四川省东风渠供水区作物需水规律与灌溉制度研究与示范”(SKY-2020-SJZX-16)。

摘　　要：为有效提升干旱半干旱地区农业水资源管理水平,基于关中平原6个代表性站点1962—2016年逐日气象资料,计算关中东部和关中西部年有效降水量(P_(ey))、年作物需水量(ET_(cy))及其边缘分布函数,运用Copula函数构建了P_(ey)和ET_(cy)的二维联合概率分布模型,评估了关中平原农业水资源短缺风险。结果表明:关中东部P_(ey)和ET_(cy)分别服从对数正态分布和广义极值分布,关中西部P_(ey)和ET_(cy)分别服从伽马分布和广义极值分布,关中东部的农业水资源短缺程度明显高于关中西部;关中东部、关中西部均表现为当ET_(cy)处于高水平(p≤37.5%)或P_(ey)处于低水平(p≥62.5%)时,自然降水和作物需水处于不协调状况的可能性较高,供水不能满足需水要求的概率较大,重现期较短(1~4 a),农业水资源短缺风险较高,建议关中平原建立与水资源承载能力相适应、与节水增收目标相配套的种植业结构。In order to effectively improve the management level of agricultural water resources in arid and semi-arid regions,we calculated the annual effective precipitation(P_(ey))and annual crop water requirement(ET_(cy))with the marginal distribution function of the eastern and western Guanzhong Plains based on the daily meteorological data from six representative stations in the Guanzhong Plain from 1962 to 2016.We mainly used the Copula function to construct a two-dimensional joint probability distribution model of P_(ey) and ET_(cy) to assess the risk of shortage of agricultural water in the Guanzhong Plain.The results show that:P_(ey) and ET_(cy) in the eastern part of Guanzhong followed the lognormal distribution and generalized extreme value distribution,respectively,and the P_(ey) and ET_(cy) in the western part of Guanzhong followed the gamma distribution and generalized extreme value distribution,respectively;the shortage of agricultural water resources in the east of Guanzhong was obviously higher than that in the west of Guanzhong;when ET_(cy) was at a high level(p≤37.5%)or P_(ey) was at a low level(p≥62.5%)in eastern Guanzhong and western Guanzhong,there was a high probability that the natural precipitation and crop water demand were in an uncoordinated state,and the return period was short(1~4 years),the probability that the water supply could not meet the water demand was greater,and the risk of agricultural water shortage was higher.The research results can provide an important basis for the adjustment of crop planting structure.It is suggested that the cropping structure that is compatible with the carrying capacity of water resources and the goal of saving water and increasing income in the Guanzhong Plain should be established.

关 键 词：关中平原 COPULA函数 有效降水量 作物需水量 农业水资源短缺 

分 类 号：P426.6[天文地球—大气科学及气象学] S274.3[农业科学—农业水土工程]