石灰岩山地不同植被类型土壤活性有机碳变化研究

Soil active carbon in soils under different vegetation communities in the limestone mountain

对徐州石灰岩山地4种不同植被类型中的两种土壤活性有机碳的含量进行研究,结果表明:微生物生物量碳(SMBC)、土壤水溶性有机碳(WSOC)的含量在针阔混交林、落叶阔叶林、针叶林、灌草地4种不同植被群落中均随灌草地向林地变化而呈现上升趋势。其中,微生物生物量碳在4种不同植被群落中的变化趋势为针阔混交林>落叶阔叶林>针叶林>灌草地;水溶性有机碳在4种不同植被群落中的变化趋势为落叶阔叶林>针阔混交林>针叶林>灌草地。两种土壤活性有机碳与总有机碳、全氮和pH值等主要生态因子的相关性均达到显著水平或极显著水平。在徐州石灰岩山地地区,与当地大面积栽植的侧柏相比,落叶阔叶林和针阔混交林可作为更好的替代树种,能够有效地改善土壤肥力状况。

In this study, the characteristics of the two kinds of soil active carbon were systematically studied by sampling analysis and laboratory testing under different typical vegetation communities in the condition of limestone mountain in Xuzhou. The results showed that the study to the characteristics of the soil active carbon under different typical vegetation communites demonstrate that the amount of the soil microbial biomass carbon （SMBC） and water soluble organic carbon （WSOC） both increased along with the transforming from grassland to forestland. Among the transformation, the variation tendency of SMBC under different vegetation communites was MBF （Mixed Broadleaf-conifer Forest）〉DBF（Deciduous Broadleaf Forest）〉CF（Coniferous Forest）〉BGL（Bush-Grass Land）, the variation tendency of WSOC under different vegetation communites was DBF〉MBF〉CF〉BGL. In the limestone mountain of Xuzhou, mixed broadleaf-conifer and deciduous broadleaf forest can be the substitute tree for Platycladus orientalis planted in large local areas, which ean efficiently improve condition of soil nutrient fertility.