Guo Xiaomin

Response of soil sulfur availability to elevation and degradation in the Wugong Mountain meadow, China

Li Z., Zhang L., Chen J., Zhang X.L., Yu S.Q., Zhang W.Y., Ma X.C., Guo X.M., Niu D.K. (2017): Response of soil sulfur availability to elevation and degradation in the Wugong Mountain meadow, China. Plant Soil Environ., 63: 250–256. Vegetation restorations of degraded meadows have been widely implemented. The evaluation of soil nutrient changes as affected by degradation is vital for efficient restorations. However, while macronutrients (nitrogen, phosphorus and potassium) have been widely investigated, sulfur (S) as one important element correlated tightly with other nutrients has not been thoroughly studied. Two studies were conducted to determine changes of sulfur as affected by degradation and elevation gradients. The results showed that available S (AS) changed non-linearly with elevation and the first principal component based on other soil nutrient variables. Soil AS depended on degradation levels and contributed substantially to the separation of meadows with different degradation levels. Moreover, AS responded stronger to changes in elevation gradients and degradation levels compared with other major nutrients. Thereby, AS could be an important nutrient responding to meadow disturbance, which should be considered in future studies on meadow soil nutrients cycling and vegetation restorations. The findings have implications for ecological restoration of degraded meadows with respect to soil nutrient management and conservations.

Ecological Benefit of Reforestation in a Severely Degraded Red Soil Region

Guifeng, Yiyang County, belongs to a seriously degraded red soil region. In 1991, Pinus elliottii and Lespedaza spp. were the species selected for the establishment of a mixed forest in the area. The results of an investigation of the soil system in a 12-year-old forest indicated the following: (1) Organic matter and total nitrogen of the forest soil to a depth of 40 cm were 88.0 and 36.0% higher, respectively, than those of a control plot; total phosphorus and available phosphorus were 40.9 and 22.3% higher than those of the control; available potassium contents were 8.13% lower than those of the control. (2) Soil aeration and the soil air regime improved. (3) Proteinase, catalase, and urease in the forest soil to a depth of 40 cm were usually higher than those in the control plot and decreased with soil depth.