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以宁化县紫色土侵蚀区3种植被恢复模式(林果草模式、油茶模式、乔灌草模式)为研究对象,以未治理的裸露荒地(CK_2)、无明显水土流失的林分(CK_1)作为恢复前后的参照,研究土壤团聚体和理化性质的变化,分析3种植被恢复模式的优劣。结果表明:与CK_2相比,3种植被恢复模式>0.25 mm水稳性团聚体含量均显著提高,促进土壤从微小团聚体向大团聚体转变,土壤容重降低,孔隙度增加,土壤有机碳含量提高,以乔灌草和林果草模式为最优,但这2种模式差异不明显;植被恢复后的紫色土团聚体破坏率(PAD)和分形维数(D)值均有降低,团聚体平均重量直径(MWD)值明显增加,以乔灌草模式的变化幅度最大,表明该模式改善土壤结构的效果优于其它模式,其土壤结构较为稳定。相关分析表明,水稳性团聚体稳定性与土壤粒径、容重及孔隙度有显著相关性。
Taking three types of vegetation restoration model (forest fruit grass model, Camellia oleifera pattern, tree and shrub pattern) in purple soil eroded area of Ninghua County as research object, using uncultivated wasteland (CK_2), no significant soil erosion (CK_1 ) As a reference before and after restoration, to study the changes of soil aggregates and physicochemical properties, and to analyze the advantages and disadvantages of the three vegetation restoration models. The results showed that compared with CK_2, the content of water stable aggregates> 0.25 mm in three vegetation restoration modes increased significantly from small aggregates to large aggregates, soil bulk density decreased, porosity increased, soil organic carbon content But the differences between the two modes were insignificant. The PAD and the fractal dimension (D) values of purple soil decreased after vegetation restoration, The body weight average diameter (MWD) value increased obviously, and the change range of the tree shrubs and shrubs was the largest. It showed that this model had better soil structure improvement than other models and the soil structure was stable. Correlation analysis showed that the stability of water-stable aggregates was significantly correlated with soil particle size, bulk density and porosity.