Study On Soil Ecological Characteristics Of Different Vegetation Restoration On Poyang Lake Desertified Land

Poyang Lake, located in Jiangxi province, is one of the most important wetland in China. With the increasing of population, productivity, life activities and the ever-changing climate in Poyang Lake region, serious desertification are happening there. In this paper, three vegetation restoration patterns(mono-cultivar planting of Pinus elliottii, mono-cultivar planting of Fructus viticis forest and mono-cultivar planting of Black locust forest) were studied in a sandy land in Liaohua town, Xingzi country, the physical and chemical properties of soil, soil respiration and enzyme activity were detected and analyzed to evaluate the effect of the four kinds of vegetation restorations. Results were shown as follows.1. The soil powder/clay, porosity, field capacity, water capacity, and soil respiration intensities in the three kinds of forest, are some degree higher than the naturally, while, soil bulk density of Pinus elliottii forest and Fructus viticis forest are lower than that. The most obvious effect of improving is Pinus elliottii.2. The soil respiration of the three kinds of vegetation recovery patterns are stronger than the naturally, the strongest one is Pinus elliottii forest, followed by Black locust forest,and Fructus viticis forest.3. After the vegetation restoration, soil nutrient status has an effective improvement, especially in the topsoil(0-20cm). Soil organic matter, nitrogen, total phosphorus content of the three kinds of vegetation recovery patterns have increased more than the Natural restoration area; except Pinus elliottii, the soil Phosphorus content of other two recovery modes are much higher than Natural recovery; the order of Total Nitrogen content from high to low is Fructus viticis forest, Pinus elliottii forest, Black locust forest and Natural restoration land. On the vertical distribution level, the basic trend is that with soil depth increasing, soil nutrient content is reduces, but the Natural restoration land does not show this trend.4. Soil enzyme activities are significantly stronger in the three pattens compared to Natural restoration area. Soil urease, sucrose and cellulase activities are all most active in Pinus elliottii pattern. Fructus viticis pattern has the most active phosphatase, while Black locust has the most active catalase. On the vertical distribution level, the basic trend is that soil enzyme activities decreases as soil depth increasing.5. The soil physical and chemical properties, soil nutrient content, other soil environmental properties showed strong positive correlations with soil enzyme activities, especially field capacity, water capacity, total porosity, organic matter, alkali-hydrolyzable nitrogen, total phosphorus. It proved that Soil enzyme activities can indicate soil fertility and soil quality.6. Soil fertility and soil quality under the three vegetation modes were obvious better than the natural, comprehensively considering soil carbon, nitrogen, phosphorus content, soil enzyme activities and factors. Pinus elliottii pattern got the highest score, which means the best vegetation restoration pattern among the four is the Pinus elliottii pattern.