Effects of Dodonaea viscosa Afforestation on Soil Nutrients and Aggregate Stability in Karst Graben Basin

Dodonaea viscosa is widely cultivated in the karst graben basin and crucial for recovering land after rocky desertification. However, effect of long–time D. afforestation on changes quality soil remains unclear. Soil nutrients aggregate composition can be used to evaluate beneficial effects improving functional stability. In this study, stability were investigated using cropland, 10–year, 20–year, 40–year secondary succession shrub. Compared significantly increased water content (WC), organic carbon (SOC), total nitrogen (TN) contents, with an enhanced observed prolonged afforestation. nutrient contents under rapidly reached level promoted formation >2 mm aggregates decreased ratio 0.053–0.25 aggregates, which varied years. >0.25 water–stable (R>0.25), mean weight diameter (MWD), geometric (GMD) exponentially. erodibility factor (K) unstable index (EIt) exponentially afforestation, latter two indicators did not reach These results indicated that nutrients, stability, erosion resistance exhibited by could shrub a long time.