流域演化过程中天文辐射空间分布

Spatial distribution of astronomical radiation during watershed evolution

基于九期人工降雨模拟流域DEM数据,运用MATLAB进行了演化条件中的流域天文辐射计算,并模拟了流域内各阶段年天文辐射量空间分布.采用统计学中均值、变异系数、峰度及偏度量化了天文辐射的数量特征,运用景观生态学指标量化了其空间结构特征.结果表明:流域演化各阶段年天文辐射的数值变化在2~12596 MJ∙m-2之间.辐射量景观格局的变化特征方面得出:斑块层次上各景观指数在小流域不同演化阶段的变化规律基本一致,而景观层次上的各指数则呈现波动性变化特征.此外,活跃演化阶段(实验阶段Ⅳ~Ⅵ)天文辐射量的数量特征及空间结构特征的变化程度最为明显.

In the report,based on the DEM data of the nine artificial rainfall simulation basins,MATLAB was used to calculate the astronomical radiation of the basin under evolutionary conditions,and the spatial distribu⁃tion of annual astronomical radiation in each stage of the basin was simulated.The statistical methods such as mean,coefficient of variation,kurtosis,and skewness,were used to quantify the quantitative characteristics of astronomical radiation,and the landscape ecology indicators were used to quantify the spatial structure charac⁃teristics.The results indicated that the numerical variation of annual astronomical radiation in the different stag⁃es of watershed evolution ranges from 2 to 12596 MJ∙m-2.From large to small,the average astronomical radia⁃tion value is in the early evolution stage,the active evolution stage,and the stable evolution stage,respectively.From large to small,the degree of difference of the radiation amount is in the active evolution stage,the stable evolution stage,and the early evolution stage.At the different stages of the evolution in small watersheds,the variation patterns of various landscape indices at the patch type level were basically consistent,while the land⁃scape indices at the landscape level exhibited fluctuating characteristics.In addition,the changes of the quanti⁃tative and spatial structural characteristics of astronomical radiation during the active evolution stage(experi⁃mental stages IV~VI)were significant.