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- 2016
四川省典型种植制度下农业干旱风险研究Keywords: 四川省,降水满足度,粮食因旱减产率,正态分布,信息扩散理论Sichuan province precipitation satisfied degree output reduction due to drought normal distribution function information diffuse theory Abstract: 中文摘要: 本文利用四川省农业生态区8个代表站1960-2012年逐月气象资料及四川省1988-2007年粮食产量、粮食因旱减产量计算四川省在“小麦-玉米-红薯”和“小麦-水稻”2种典型种植制度下的降水满足度和粮食因旱减产率,同时分别采用正态分布函数研究降水满足度、采用信息扩散理论研究粮食因旱减产率发生农业干旱的风险概率。结果表明:2种典型种植制度下,除盆西高原盆地过渡区、川南中低山丘陵区外,四川省大部分农业生态区每5年中约有1年降水不能满足作物需水量;“小麦-玉米-红薯”和“小麦-水稻”种植制度下中旱、重旱、严重干旱发生概率分别为39.7%、10.9%、4.9%和32.7%、6.1%、3.2%;降水满足度和粮食因旱减产率呈显著负相关;粮食因旱减产率指示发生中旱及以上干旱时对应的降水满足度距平指示一定发生干旱,降水满足度距平指示发生干旱时对应粮食因旱减产率指示不一定是中旱及以上。Abstract:The monthly meteorological data from 1960 to 2012 in 8 stations in Sichuan agricultural regions was used to calculate the precipitation satisfied degree, and the grain production and reduction due to drought in Sichuan from 1988 to 2007 was used to calculate the grain reduction rate in “wheat-rice” and “wheat-corn-sweet potato” cropping systems respectively. The drought risk probability of the precipitation satisfied degree was calculated by normal distribution function, and of the grain reduction rate due to drought was studied by information diffuse theory. The results showed that under the two cropping systems precipitation can’t satisfy the crop water requirement in one year every five years in most agricultural regions of Sichuan province, so the irrigation is needed. In “wheat-rice” and “wheat-corn-sweet potato”, the probability of medium drought, heavy drought and severe drought is 39.7%、10.9%、4.9% and 32.7%、6.1%、3.2%, respectively. The precipitation satisfied degree is well related with the grain reduction rate. When the grain reduction rate indicated medium or heavy drought, the precipitation satisfied degree anomaly must indicate the occurrence of drought. However, when the precipitation satisfied degree anomaly indicated the occurrence of drought, the grain reduction rate did not necessarily judge the medium or heavy drought.
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