关中平原小麦生育期VTCI加权估算及其与产量的相关性研究

摘要

选取关中平原冬小麦主要生育期的条件植被温度指数( VTCI)遥感干旱监测结果,运用层次分析法、因子权重排序法两种主观赋权法和主成分分析法、熵值法两种客观赋权法,分别确定加权VTCI,并与关中平原5地区冬小麦年产量建立线性回归模型,研究VTCI对冬小麦产量的影响.结果表明,两种主观赋权法确定的加权VTCI与产量之间存在着较好的线性相关关系,两种客观赋权法确定的加权VTCI与产量之间不存在明显的线性相关关系,表明了主观赋权法是一种较好的确定加权VTCI的方法,可根据其建立加权VTCI与产量的线性相关关系,同时验证了用VTCI预测小麦产量的可行性,这些对监测关中平原旱情具有重要的借鉴意义.%Selecting drought monitoring results of Vegetation Temperature Condition Index (VTCI) in the key growth and development stages of winter wheat in the Guanzhong Plain, two subjective weighting methods, analytic hierarchy process method and factor rank ordering method, and two objective weighting methods, principal component analysis and entropy method are used to calculate weighted VTCI values. The linear regression analysis is applied to study the correlation between the weighted VTCI values and wheat yields for the five regions in the Cuanzhong Plain respectively, and as well as the drought impact on wheat yield based on VTCI. The results show that there are significant correlations between wheat yields and weighted VTCI values by using the subjective weighting methods, while there are poor correlations by using the objective weighting methods. These results indicate that the subjective weighting methods are more effective ways to calculate weighted VTCI values, which can be used to establish the linear relationship with wheat yields, prove the feasibility of wheat production forecast by using VTCI approach, and show that monitoring drought in the Guanzhong Plain is very referable.