基于地统计和GIS的河南省烟草大田生长期降水量和蒸发量空间变异性分析

地统计学方法是研究具有结构和区域双重性质变量的空间变异性的一种方法.它提供的克立格(knging)法是一种最优的无偏内插方法.在分析河南省1950～2000年整编气象资料的基础上,采用地统计学与GIS相结合的方法,从大尺度角度上研究了河南省范围内烟草大田生长期间的总降水量、总蒸发量和盈亏量的空间变异性.经典统计学表明,上述各气候因子在河南省境内均可以拟合成较好的正态分布,满足地统计学所要求的平稳假设条件.变异系数最大的是烟草大田生长期水分盈亏量(即全年蒸发量 全年径流量-全年降水量)为30.87%,最小的是烟草大田生长期间的蒸发量,只有10.15%.地统计学分析表明3种气候要素在河南省境内的分布均可拟合成高斯模型.3种气候要素在研究区内均具有强烈的空间相关性,变异尺度以烟草大田生长期降水量的最小,只有2 397km,而烟草大田生长期间的盈亏量最大,为5 307km.采用kriging方法进行最优内插,绘制了河南省境内烟草大田生长期间各气候要素的空间分布图.图3,表2,参17.

Spatial Variance Characteristics of Rainfall and Evaporation During Tobacco Growth in He'nan Province

In this paper,based on analyzing climatic material of He'nan province between 1950 to 2000,the spatial variability and distribution characteristics of rainfall during tobacco growth,evaporation during tobacco growth,profit and loss of water during tobacco growth in He'nan province are studied by using geostatistical method combined with GIS.The statistical results indicated that coefficients of variation of profit and loss of water during tobacco growth is the greatest among all aboved mentioned,which is 30.87%.And the coefficient of variation of evaporation during tobacco growth is the smallest,which is 10.15%.Analysis of the isotropic variogram indicated that rainfall during tobacco growth,evaporation during tobacco growth,profit and loss of water during tobacco growth semivariogram were well described with Gaussian models,with the distance of spatial dependence being 2 397 000,2 733 000 m and 5 307 300 m respectively.Three climatic factors were all strongly spatially dependence with C0/sill being 6.1%,9.4% and 9.5% respectively.The Kriging method and GIS technique were applied to calculate the unobserved points and were used to generate the contour map.