关键词: 土壤有机质含量, 空间变异性, 黑土区, 适宜样本容量

Abstract: The spatial variability of soil organic matter content in sampling areas of 64 m×64 m, 80 m×80 m and 112 m×112 m and its suitable sample size were studied with classical statistics and geostatistics methods. The results showed that the soil organic matter content in different sampling area had moderate variation degree, as sampling area increased, the mean of soil organic matter content first increased and then decreased, and the variation degree of soil organic matter content gradually increased, but their change was small; Spatial correlation ranges of soil organic matter content in different sampling area respectively were 66.69, 85.02 and 12.00 m, their spatial correlation degree were moderate, as sampling area increased, spatial correlation range of soil organic matter content first increased and then decreased, and its spatial correlation degree first decreased and then increased; When precision coefficient was the same, as sampling area increased, suitable sample size of soil organic matter content gradually increased, but increasing degree was small; When sampling area was the same, as precision coefficient increased, suitable sample size of soil organic matter content gradually decreased, and decreasing degree was large.

Key words: soil organic matter content, spatial variability, black soil region, suitable sample size