关键词: 次生林, 土壤有机质, 空间异质性, 变异函数, 空间格局

Abstract: [Objective] Populus davidiana+Betula platyphylla natural secondary forest was used as research objective in this study. The aim of this study was to explore the vertical distribution and spatial variation of soil organic matter of the forest. [Method] Field survey data, statistics and GIS spatial structure analysis techniques were used in this study. [Results] The content of soil organic matter was the highest in the 0-20 cm layer but the content of 20-40 cm was the lowest. The coefficient of variation increased with increasing soil depth and three layers belonged to moderate variation. The best theoretical models of organic matter in three layer were exponential, Gaussian and spherical models. Each layer organic matter content focus area and interpolation analysis grade area was different, but the overall change was the same. Soil organic matter of 0-20 cm layer was the largest. Soil layer of 20-40 cm was the lowest and most of organic matter was consumed in this layer. Soil layer of 40-60 cm was in a medium level. [Conclusion] The soil environment of secondary forest of Populus davidiana+Betula platyphylla was disturbed less by human activity. The vertical variation was not significant. The formation of organic matter of parent material and soil organic matter consumption were in a reasonable range, indicating that the forest soils of the study area are in good conditions of healthy, sustainable development.

Key words: natural secondary forest, soil organic matte, spatial variability, variogram, spatial pattern