Spatial variability of soil organic matter in small scale across a cropland
ZHANG Fa-sheng1,2, LIU Zuo-xin1, SHEN Ye-jie1,2, TONG Na1
1. Key Laboratory of Liaoning Water-saving Agriculture, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; 2. Graduate University of Chinese Academy of Sciences, Beijing 100049, China
Data of 1024 samples (0-20cm) collected from a 10.24 hm2 cropland in a dense grid of 10m×10m were used to analyze and quantify spatial variability of soil organic matter(SOM) by geostatistical method.Within the study area,soil organic matter had weak variability as CV = 1.84%,but it was entirely low in the content no more than 1.04%.The semi-variogram of soil organic matter after eliminating the trend had low nugget variance 0.00005,small ratio of nugget to sill 0.135 and long range 145.5m.The standard variance of Kriging estimation 0.00943% was also extremely low.Our results showed soil organic matter had strong spatial dependence across the cropland and the spatial correlation range was very large.
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