西南喀斯特地区石灰岩与白云岩发育土壤的养分含量

Nutrient Content of Soil Developed from Limestone and Dolomite in Karst Areas of Southwest China

【目的】为喀斯特地区土壤养分管理和可持续经营提供借鉴和参考。【方法】在贵州省施秉县的白云岩区白垛村、石灰岩区石桥村采集林地和旱地的土壤样品,对其进行土壤养分分析。【结果】白云岩发育的土壤具有较高的有机质、全氮、有效磷、速效钾和水解氮,石灰岩土壤具有较高的全磷和全钾;石灰岩和云岩发育土壤的全氮与水解氮和有机碳呈极显著正相关系,水解氮与有机碳在石灰岩区为显著正相关关系,在白云岩区呈极显著正相关关系;土地利用方式对两种岩性发育土壤的养分含量具有明显的影响,石灰岩林地土壤全钾、全氮、水解氮、有机碳含量高于旱地,速效钾、全磷、有效磷、pH低于旱地;白云岩林地土壤全磷、有效磷低于旱地,其他指标均高于旱地;白云岩发育的土壤养分有机质、全氮、全磷、全钾含量分级分别为二级、一级、六级和三级,石灰岩发育土壤的分别为二级、一级、五级和一级;【结论】土壤养分既受成土母岩的影响也受土地利用方式的影响。

【Objective】The objective of the paper is to provide a reference for soil nutrient management and sustainable operation in Karst areas.【Method】The soil samples were collected from woodland and dry land in Baiduo Village(dolomite areas) and Shiqiao Village(limestone areas) in Shibing County,Guizhou Province,and then the soil nutrient was analyzed.【Result】The soil developed from dolomite was featured with higher organic matters,total N,available P,available K and hydrolysable N.The soil developed from limestone was featured with higher total P and total K.Total N was positively and very significantly related to hydrolysable N and organic carbon in soil developed from limestone and dolomite.Hydrolysable N was positively and significantly related to organic carbon in limestone areas.Hydrolysable N was positively and very significantly related to organic carbon in dolomite areas.Land use patterns had obvious effects on nutrient content in soil developed from limestone and dolomite.Soil total K,total N,hydrolysable N and organic carbon content in limestone woodland was higher than dry land,and available K,total P,available P and pH was lower than dry land.Soil total P and available P in dolomite woodland are lower than dry land,and other indexes are higher than dry land.The organic matter,total N,total P and total K content in dolomite-developed soil was Grade Ⅱ,Grade Ⅰ,Grade Ⅵ and Grade Ⅲ respectively.The organic matter,total N,total P and total K content in limestone-developed soil was Grade Ⅱ,Grade Ⅰ,Grade Ⅴ and Grade Ⅰ separately.【Conclusion】Soil nutrient was not only affected by soil forming rock,but also affected by land use pattern.