水产养殖与植被恢复对红树林湿地土壤的影响

通过对原生红树林、养殖虾塘和鸭塘、废弃虾塘表层土壤中全氮、全磷、全钾、土壤微生物总DNA以及土壤有机碳指标测定,得到养殖对红树林湿地土壤的影响以及红树林恢复对废弃虾塘土壤的修复作用。结果显示：原生红树林中的全氮和土壤有机碳含量较高;废弃虾塘A的全氮和废弃虾塘B的土壤有机碳最低;全磷含量在鸭塘最高,在废弃虾塘B最低;全钾在废弃虾塘A中的含量较其他4个样地高,最低值为鸭塘;土壤表层微生物总DNA浓度为鸭塘最高,废弃虾塘A最低;土壤C/N随着土壤微生物总DNA的升高而降低。植被恢复后,废弃虾塘土壤中土壤有机碳、全氮升高,全钾逐渐下降,而全磷变化较大,且这4个指标总体逐渐接近原生红树林中相应指标值。说明废弃虾塘植被恢复后,土壤性质逐步接近原生红树林土壤,红树林对废弃虾塘土壤有修复功能。

Effects of Aquaculture and Vegetation Restoration on the Soil of Mangrove Wetland

Effects of aquaculture on the soil of mangrove wetland and effects of the restoration of mangrove forest on abandoned shrimp farming ponds were studied by measuring the total nitrogen （TN）, total phosphorus （TP）, total potassium （TK）, the total microbial DNA and the soil organic carbon （SOC） in the soils respectively of original mangrove forest, shrimp farming and ducking pond and abandoned shrimp farming pond. Result showed a higher contents of TN and SOC in the mangrove forest;The lowest content of TN was found in the abandoned shrimp pond （A） and the lowest content of SOC was found in the abandoned pond （B）. As for the content of TP, the highest content was found in duck pond and the lowest content in the abandoned shrimp pond B. The content of TK appeared a higher level in the abandoned shrimp pond A than all of other sample sites, and the lowest level appeared in the duck pond. The surface soil of total microbial DNA leaded the highest level in duck pond and the lowest level in the abandoned shrimp pond A. The soil C/N decreased with the increasing trend of the total microbial DNA. After plantation restoration in abandoned shrimp ponds, the SOC and TN increased, while the TK decreased gradually, and the variation range of TP was wide. But all the contents in abandoned shrimp ponds were gradually close to those of the original mangrove forest, indicating that vegetation restoration could rehabilitate the soil of the abandoned shrimp ponds.