南亚热带红椎和湿地松人工林土壤肥力的灰色关联度分析

Grey Correlative Degree Analysis of Soil Fertility of Castanopsis hystrix and Pinus elliottii Plantations in South Subtropics

为确定红椎(Castanopsis hystrix)和湿地松(Pinus elliottii)人工林的土壤肥力状况,选择土壤pH值、有机质、全氮、全磷、全钾、水解性氮、速效磷和速效钾作为土壤肥力评价指标,运用灰色关联度分析方法定量分析红椎纯林、红椎—湿地松混交林和湿地松纯林的土壤肥力,并进行综合排序。结果表明随着土层深度增加,有机质、全氮、水解性氮、速效磷和速效钾含量大体呈减小趋势,而pH值、全磷和全钾含量在不同土层中无显著性差异;红椎纯林在综合评估模型中得分最高,土壤肥力最好,红椎—湿地松混交林次之,湿地松纯林最差。

To determine the soil fertility of pure Castanopsis hystrix forest, C. hystrix –Pinus elliottii mixed forest and pure P. elliottii forest in the south subtropical area, soil pH values, organic matter, total nitrogen, total phosphate, total potassium, hydrolysable nitrogen, available phosphate, and available potassium was chosen as evaluation indicators. Soil fertility was analyzed by grey correlative degree analysis, and ranked by correlation degrees comprehensively. The results indicated that the contents of organic matter, total nitrogen, hydrolysable nitrogen, available phosphate and available potassium had decline tendency with the increase of soil layer depth, while pH value, the content of total phosphate and total potassium have no diference in fve diferent soil layers. The grey correlative degree analysis shows the best soil fertility was observed in pure C. hystrix forest, followed by C. hystrix –P. elliottii mixed forest, and pure P.elliottii forest has poorest soil fertility status.