Spatial characteristics of soil moisture and organic matter and light in Pinus tabulaeformis forest and Quercus liaotungensis forest on Dongling Mountain, Beijing, China
东灵山油松林和辽东栎林下土壤资源和光资源的空间特征

Pinus tabulaeformis forest and Quercus liaotungensis forest are among the most important vegetation in warm temperate region in China.In each forest,one transect of 100 m was set up in Dongling Mountain,Beijing,China and soil moisture,soil organic matter and light intensity were measured along the transects.Soil moisture and soil organic matter were measured along the transects at interval of 1 m.The HemiView Digital Canopy Analysis System was used to study leaf area index,canopy coverage,canopy uniformity,site light factors and radiation beneath canopy at interval of 10 m along transects.Semivariogram analysis and coefficient of variance(CV) were employed to reveal the spatial heterogeneity pattern of soil moisture and soil organic matter.There were no significant differences between the pine forest and the oak forests in terms of leaf area index,canopy coverage,and light intensities above and beneath canopy.The canopy uniformity of the pine forest was significantly lower than that of the oak forest.Positive correlations were found between indirect site light factor and total radiation beneath canopy in the pine forest(R~2=0.466,p=0.030),while the opposite was true in the pine forest(R~2=0.203,p=0.191).The quality and composition of the pine forest and oak forest were highly similar while the relationship between the composition of light and the canopy characters varied with forest types.Both soil moisture and organic matter in the pine forest were lower compared to oak forests and their heterogeneity in term of coefficient of variance was larger.Soil moisture and organic matter exhibited significant spatial autocorrelation in the oak forest, whereas did not in the pine forest.No significant negative relationship was found between the radiations beneath canopy and water content at the scale of 10m.