生物覆盖对山地杨树人工林土壤容重及稳定性影响

Effects of Different Mulching Weights on Soil Bulk Density and Its Stability in Poplar Plantation at the Mountain Area

通过对山地土壤进行不同重量的生物覆盖以研究杨树人工林土壤容重的变化及其稳定性。结果表明:随着生物覆盖量增加,不同深度的土壤容重均呈减小趋势,覆盖量7.5 kg/m2下的土壤上、下层容重最小,分别比对照减小12.52%和5.34%;土壤容重随时间呈S型变化趋势,覆盖量的大小不影响峰值出现的次数,但影响峰值出现的时间和幅度;随着生物覆盖量增加,土壤容重的稳定性在土壤上、下层均呈减小的趋势,且土壤上层稳定性较好;生物覆盖的次数也影响不同深度的土壤容重。

The effect of different mulching weights on soil bulk density and its stability in the mountain area was studied, and the results were as follows： with mulching weight increasing, bulk density decreased in different layers of soil. Compared with the control （ CK）, the decrease of bulk density in upper and lower layers of soil with 7.5 kg/m^2 mulching were about 12.52% 和 5.34% respectively. With time passing, the dynamics of soil bulk density could be described by ＂S＂ shape curves. Biological mulching weight did not affect peak numbers, but influenced peak circles and peak amplitude in ＂S＂ shape curves. As mulching weight increased, the stability of bulk density in upper and lower layers of soil was gradu- ally diminished, and the stability of bulk density in upper layer of soil was higher than in lower layer. In addition, times of mulching also influencd soil bulk density.