南方红壤区不同经济林地土壤理化特征和酶活性的对比研究

基于中国南方红壤区马尾松、桉树、蜜柚三种不同经济林地,测试土壤有机碳、活性有机碳、全氮、碱性氮、全磷、速效磷、C/N比值、土壤酶活性等参数,综合分析不同经济林地土壤理化指标和酶活性的特征差异。结果表明,马尾松林地的有机碳、活性有机碳含量和C/N比值明显高于桉树和蜜柚林地,而全氮、碱性氮、全磷和速效磷等含量在三个林地之间的差异则没有规律。这说明马尾松林地土壤有持续的新有机质补充,而桉树和蜜柚林地土壤有机质存量在逐渐消耗,滞留在土壤中的复合肥又显著改变了林地土壤的氮磷含量比例;桉树和蜜柚林地土壤酶活性明显低于基本处于无常规人工管理的马尾松林地,说明高强度的人工土地开发已显著影响了桉树和蜜柚林地的土壤肥力及土壤微生物总活性。

Comparative Study on Soil Physico-chemical Properties and Enzyme Activity of Economic Forest Lands in Red Soil Zone, Southern China

In this paperare, soil physico-chemical properties and enzyme activity of economic forest lands in red soil zone Southern China were studied. A field experiment was conducted in three economic forest lands(Pinus, Eucalyptus and Honey Pomelo).The data show that the values of soil organic carbon, active organic carbon, C/N and enzyme activity in Pinus forest lands are consistently higher than those in Eucalyptus and Honey Pomelo forest lands, and the values of total N, basic nitrogen, total P and available phosphorus are no significant difference among Pinus, Eucalyptus and Honey Pomelo forest lands. Experimental results show that, compared with Pinus forest lands, high intensity cultivation and fertilization methods have accelerated the decomposition rate of soil organic matter and reduced the soil fertility and enzyme activity in Eucalyptus and Honey Pomelo forest lands.