不同麋鹿干扰强度对栖息地土壤理化特性的影响

Effects of Père David deer (Elaphurus davidianus) grazing on soil physicochemical properties

动物对草地的采食和践踏直接影响着土壤的理化特性。以大丰麋鹿保护区半散养麋鹿为研究对象,分析了不同麋鹿干扰强度下土壤含水率、容重、全盐量、有机质、全氮、全磷和全钾的差异,探讨麋鹿放养对土壤理化性质的影响。结果表明:(1)随着麋鹿干扰强度的增加,土壤含水量和有机质呈现下降的趋势;土壤盐分、容重和氮、磷、钾全量呈现上升的趋势。(2)麋鹿放养对土壤理化指标的影响显著,重度干扰样地与对照样地之间差异性达到极显著水平(P<0.01)。(3)土壤氮、磷、钾全量,在重度干扰区域达到最大值,分别为1.56 g/kg、0.95 g/kg和13.43 g/kg,全氮量的增长幅度最大。(4)在麋鹿活动最为频繁的重度干扰区域,土壤盐分含量达到9.26 g/kg,土壤盐碱化,这是导致栖息地退化的主要原因。麋鹿干扰强度增加最终导致土壤盐渍化加重,栖息地生境明显退化,严重区域向光裸地的演化。

The physicochemical properties of soil was directly affected by grazing and trampling of animal. In order to explore the main factors affecting soil physical and chemical properties by Père David deer grazing, parameters including water content, bulk density, salt content, organic matter, total N, P and K contents under different intensity of semi-free Père David deer disturbance were analyzed. The fieldwork was conducted in Dafeng Père David deer National Nature Reserve, Jiangsu province, China. The results indicated that(1) the contents of soil water and organic matter were negatively correlated with the increase of the grazing intensity. However, the contents of soil salt content, total N, P and K contents were positively correlated with the increase of grazing intensity.(2) The soil physicochemical properties parameters between the heavy grazing and the control plots showed significant differences(P< 0.01).(3) The maximum value of total N, P and K contents was 1.56 g/kg, 0.95 g/kg and 13.43 g/kg in heavy grazing area, respectively. Especially, N content was the most remarkable parameter.(4) The soil salt content was up to 9.26 g/kg in heavy grazing area. Soil salinization was the main reason causing the habitat degradation in Dafeng nature reserve. The increasing of grazing intensity led to soil salinization and habitat degradation. The heavy salinized soil degenerated to bare land gradually.