生态与常规种植对土壤养分、微生物及重金属的影响

Effects of ecological and conventional planting pattern on soil nutrients, microbes and heavy metals

为探讨生态种植模式对土壤环境的影响,以四川成都府南河上游地区安龙村生态农业和传统农业为研究对象,比较分析了生态种植与常规种植模式对土壤养分、微生物及重金属的影响。结果表明:除细菌含量外,生态种植的土壤中微生物碳含量及真菌、放线菌数量均高于常规种植,生态种植改善了土壤中微生物群落结构;生态种植土壤中重金属Cr、Pb、Hg和As含量均低于常规种植,Cd含量相差不大,生态种植带入的重金属较少;生态种植土壤中总氮、总磷、有效氮及有效钾的含量均高于常规种植,但总钾和有效磷的含量低于常规种植,这与两种种植方式下农业投入品不同密切相关。研究表明,生态种植能一定程度提升土壤养分,改善土壤微生物群落结构,并有效减少种植带入的重金属。

We compared the traditional agriculture and ecological agriculture in Anlong Village, which located near Chengdu, Sichuan, to compare the effects of ecological and conventional planting pattern on soil nutrients, microbes and heavy metals. The results showed:While the quantity of bacteria was lower, the quantity of microbial carbon, fungus and actinomycetes in ecological planting soil was higher than in conventional planting soil, which revealed the structure of microbial community got improved in ecological agriculture;The contents of heavy metal, such as Cr, Pb, Hg and As, were much lower in the soil with ecological agriculture, which indicated that the heavy metals brought by ecological planting were less;With ecological farming the contents of total nitrogen, total phosphorus, available phosphorus and available potassium in the soil increased, but the levels of total potassium and available phosphorus decrensed, which were closely related to the different agricultural inputs. The quality of soil improved by transfering traditional agriculture to ecological agriculture in 3~10 years later. Furthermore, ecological farmers noticed that manure might cause the problem of heavy metals, so they used manure, biogas slurry as well as compost, which eased the heavy metal risk.