Using <i>Le Bissonnais</i> method to study the stability of soil aggregates in plantations and its influence mechanism
Li-Wen Lin, Yusong Deng, Gairen Yang, Daihua Jiang, Deyang Liu, Zhenxin Xu, Zhigang Huang, Ling Wang
Abstract
To evaluate the influence of different plantations on the stability of soil aggregates, we selected 5 typical plantations in south subtropical region: Pinus massoniana (PM), Cunninghamia lanceolata (CL), Eucalyptus urophylla×E. grandis (EU), Mytilaria laosensis (ML) and Castanopsis hystrix (CM). Soil aggregate stability was determined by the Le Bissonnais method and included three disruptive treatments. FW caused the greatest damage to the soil aggregate structure, after which the soil aggregates were mainly 0.2–0.5 mm in size. The MWD and GMD values of the three treatments were basically the same, i.e., WS > SW > FW, and gradually decreased with increasing soil depth. Compared to the plantations, the natural forest had higher MWD and GMD but lower RSI and RMI. Among the 5 plantation types, the SOM of the EU was lowest in five soil layers. SOM, Fe and Al had significantly positive correlations with MWD but negative correlations with Mn (p < 0.05), which indicated that SOM, Fe and Al were involved in the formation of macroaggregates and increased the stability of soil aggregates. Reasonable forest management measures will contribute to the formation of soil aggregates and the improvement of soil quality.