不同载畜率下短花针茅草原土壤水分空间异质性的分析  

Spatial heterogeneity of soil moisture in Stipa breviflora grasslands under different stocking rates

作　　者：王亚婷[1] 张宇 杜宇凡 王玺[1] 赵天启[1] 古琛[1] 陈万杰[1] 赵萌莉[1] 

机构地区：[1]内蒙古农业大学生态环境学院,内蒙古呼和浩特010018 [2]内蒙古鄂尔多斯市环保局,内蒙古鄂尔多斯016100

出　　处：《草业科学》2017年第6期1159-1167,共9页Pratacultural Science

基　　金：国家自然科学基金(31460110;31170446);内蒙古农业大学草地资源教育部重点实验室

摘　　要：以短花针茅(Stipa breviflora)草原为研究对象,采用经典统计学和地统计学的方法对不同载畜率样地(不放牧、轻度放牧、中度放牧和重度放牧)的土壤水分进行描述性统计、半变异函数及空间插值分析,旨在研究载畜率对荒漠草原土壤水分空间异质性的影响。结果表明,01)各处理的土壤含水量均随载畜率的增大而逐渐升高,各处理的变异系数(CV)在7.29%~9.79%,均呈弱变异性。2)半变异函数分析显示各处理的土壤水分含量均呈指数模型,不放牧的结构比为74.4%,属于中等程度变异。轻度、中度、重度放牧处理的结构比分别为94.4%、91.2%和96.0%,具有强烈的空间自相关性;3)利用克里格插值法对各样地的未知采样点进行插值分析,发现重度放牧处理土壤水分的空间变异程度最大,不放牧处理土壤水分的空间变异程度最低。所以,载畜率对土壤水分的空间分布有明显的影响。The effects of stocking rates on spatial heterogeneity of soil moisture in a Stipa breviflora desert steppe ecosystem were investigated. Both classical statistics and geo-statistical methods were adopted to generate descriptive statistics, semi variogram analysis, and spatial interpolation methods for soil moisture in four types of sample plots. The results indicated： 1） The mean value of soil moisture in all different sample plots increased with increase in stocking rates, the coefficient of variation （CV） in each sample plot changed within the range of 7.29% to 9.79%, presenting weak variability. 2） The semi-variogram analysis indicated that the content of soil moisture in each sample plot was found to be in line with the exponential model, the structural variation ratio of non-grazing was 74.4 %, its value was less than 75 %, which corresponded to moderate variability. The C/（C0＋C） values of lightly, moderately and heavily grazed areas were 94.4%, 91.2%, and 96.0%, respeetively; all values were larger than 75%, which corresponded to strong spatial auto-correlation. 3） The Kriging interpolation method was used to deal with interpolative analysis for unknown sampling points of each sample plot, and the results showed that the spatial variability of soil moisture for heavily grazed area was largest, while that for non-grazing was lowest. Our analyses showed that different stocking rates had different in, pacts on spatial patterns of soil moisture.

关 键 词：家畜放牧 短花针茅 土壤水分 空间异质性 变异系数 克里格插值 半变异函数 

分 类 号：S812.2[农业科学—草业科学]