Effects of Cutting Disturbance on Spatial Heterogeneity between Root Biomass of the Herb and Soil Environment in Larix principis-rupprechtii Forests in Guandi Mountain

Based on theory and methodology of spatial pattern analysis in geostatistics,samples were taken at three soil depths(0-10 cm,10-20 cm,and 20-30 cm) using soil core(7.0 cm in diameter).Effects of spatial heterogeneity between the herb fine root(≤2 mm)biomass of Larix principis-rupprechtii and soil characteristics(soil moisture,pH,total N,NO-3-N,NH +4-N) were analyzed.The results showed that herb root biomass was 31.17 g/m2 in the disturbed stand(plot A),which was significantly less than that of the undisturbed plot(72.01 g/m2),and root accumulated in the upper soil layer.At the 0-10 cm soil layer,spatial heterogeneity(C0+C=31330.0) and spatial autocorrelation(C/C0+C=92.5%) enhanced obviously and exhibited a distinct spatial dependence in the disturbed stand.After cutting disturbance,the correlation between root biomass of herb and soil moisture,pH,total N,NO-3-N,NH + 4-N increased.However,the correlation between herb root biomass and fine root biomass of Larix principis-rupprechtii was stronger in the undisturbed plot.