松阳县毛竹林地土壤养分空间变异特征分析

Spatial Variability of Soil Nutrient Content in Phyllostachys edulis Stands in Songyang County

为掌握松阳县毛竹Phyllostachys edulis林地土壤养分的基本情况及其变异特征,以地统计学半方差方法分析研究毛竹林地土壤的pH及有机质、全氮、碱解氮、全钾、速效钾、全磷、有效磷7个主要养分因子的空间变异特征。结果表明,毛竹林地土壤pH平均值为4.75±0.28、有机质含量的平均值为42.94±10.47 g·kg^-1、全氮含量的平均值为2.15±0.96 g·kg^-1、碱解氮含量的平均值为159.79±70.49 mg·kg^-1、全磷含量的平均值为0.19±0.09 g·kg^-1、有效磷含量的平均值为2.27±1.45mg·kg^-1、全钾含量的平均值为10.01±2.95g·kg^-1、速效钾含量的的平均值为61.28±26.6mg·kg^-1;用经典统计学分析发现土壤有机质、全氮、碱解氮、全钾、有效磷和全磷都有较大变异;利用地统计学半方差特征参数函数分析各养分的理论拟合模型发现,全氮和有效磷含量分布符合球状模型,有机质、全磷和全钾含量分布符合高斯模型,碱解氮和速效钾含量分布符合指数模型;各养分的块金系数在25%~75%,为中等空间自相关性。结合该县毛竹林经营行为等综合因素分析认为,松阳县毛竹林土壤主要养分空间变异是自然过程和人为经营活动共同作用的结果,人工经营、气候、林地破碎性和养分随水土的流失等原因改变了土壤原本的连续变化,是产生土壤养分空间变异的主要原因。

In December 2014 and January 2015, soil samples were collected at Phyllostachys edulis stands in 18 villages of Songyang county, Zhejiang province. Determinations were conducted on soil pH, content of organic matter, total nitrogen, available nitrogen, total potassium, available potassium, total phosphorus and available phosphorus. The result demonstrated that mean pH was 4.75±0.28, average organic matter content of 42.94±10.47 g/kg, average total nitrogen content of 2.15±0.96 g/kg, average available nitrogen content of 159.79±70.49 mg/kg. The average total phosphorus content, available phosphorus content, total potassium and available potassium content was 0.19±0.09 g/kg, 2.27±1.45 mg/kg, 10.01±2.95 g/kg, 2.27±1.45 g/kg, 61.28±26.6 mg/kg respectively. Statistical analysis showed that there were significant variations among soil nutrient contents. Analysis by semi-variogam resulted that distribution of total N and available P was in accordance with spherical model, that of organic matter, total P and total K with Gaussian model, and that of available N and available K with exponential model. The nuggest coefficient of each nutrient was 25%-75%, meaning a medium spatial autocorrelation. Based on analysis of comprehensive factors such as bamboo management, it concluded that the spatial variation of main nutrients in the soil of bamboo stands in Songyang was the result of interaction of natural process and management activities.