生态恢复红壤区土壤微生物活性的对比研究

基于生态恢复红壤区林地和耕作农地的现场实验,以土壤微生物体系为研究对象,通过分析测试土壤微生物数量、土壤呼吸强度、土壤酶活性等参数,综合探讨生态恢复红壤区土壤微生物活性的变化特征。结果表明,生态恢复时间分别为34、26、15、10年的4个林地的土壤有机碳、全氮、全磷等不同养分含量和C/N比值明显高于2个农地,且生态恢复时间越长,土壤养分含量越高,C/N值越大;综合土壤微生物(细菌、放线菌和真菌)数量、土壤呼吸强度、土壤酶(蛋白酶、脲酶、过氧化氢酶)等多个衡量土壤微生物活性的重要指标,生态恢复林地的土壤微生物活性均明显高于农地,且生态恢复时间越长,土壤微生物活性越强。不同生态恢复时间的林地之间土壤微生物活性的差异并不显著,表明在南方红壤区较为适宜的水热条件,较短时间即可重建并恢复土壤生态系统动态平衡。

Comparative Study on Microbial Activity of Red Soil from Ecological Restoration Zone

In this study, based on field test, microbial activity of red soil from ecological restoration zone was systematically investigated in three aspects including soil microbial quantities, intensity of soil respiration and soil enzyme activities. Experimental results show the values of soil organic, total N, total P and C/N in forestlands (ecological restoration period of 34, 26, 15, and 10 a, respectively) were consistently higher than farmland, and the values increase with ecological restoration time. The soil microbial activity of forestlands, representing soil microbial quantities (bacteria, actinomycete, and fungi), intensity of soil respiration and soil enzyme activities (protease, urease, and catalase), were consistently higher than farmland, and the values increase with ecological restoration time. Differences of microbial activity among 4 forestlands are not significant, indicating that because of appropriate climatic conditions for red soil in southern China, the dynamic balance of ecological restoration of soil ecosystems can be reconstructed and restored in several years or decades.