黎塘岩溶区铁锰结核背景下的土壤研究

Study on Soil of Fe-Mn Nodules Background in Litang Karst

对黎塘岩溶区铁锰结核背景下的土壤进行了分析。结果表明:研究区土壤以硅质土为主,土壤发育呈幼年性。土壤多呈中性,对土壤肥力的发挥及旱地作物的生长较为有利;有机质含量A层多为中等(Ⅲ级)或丰富(Ⅳ级),B层为缺乏(Ⅱ级);全N含量A层多为中等(Ⅲ级),B层多为缺乏(Ⅱ级),有效N含量A层多为丰富(Ⅳ级)或甚丰富(Ⅴ级),B层多为中等(Ⅲ级)或缺乏(Ⅱ级),A、B层养分含量的差异说明农耕区土壤受表层耕作、施肥影响较为显著。土壤有效P整体表现为缺乏或甚缺乏,可能已成为旱地作物生长的主要限制因子,阳离子交换量多表现为保肥力中等。

SOil of Fe - Mn nodules background in Litang karst was analyzed. The results showed that ： the soil was mainly siliceous and juvenile; soil was mainly neutral and was beneficial for dryland crops; organic matter content in A layer was mostly middle （Ⅲ grade） or rich （Ⅳ grade）, while that in B layer was lack （Ⅱ grade） ; the total N content in A layer was mostly middle （Ⅲ grade）, while that in B layer was lack （Ⅱ grade） ; the effective N content in A layer was mostly rich （ Ⅳ grade） or even rich （ Ⅴ grade）, while that in B layer was mostly middle （Ⅲ grade） or lack（Ⅱ grade）. The nutrient difference between A layer and B layer indicated that surface farming and fertilization played important role. Effective P in the soil was overall lack and may have become the major limiting factor for growth. CEC was mostly middle for fertility capacity.