The utilization status of biogas fermentation products in 107 pig farms in Ankang city was surveyed. Four different types of soils near 16 pig farms were collected and the contents of nutrients and accumulation of salts were also determined. The survey showed that there was less than 50% of utilization rate of biogas slurry and biogas residue of biogas fermentation in pig farms. Stacking or discharging near the pig farms were usual treatment methods for these products. The test results on soil showed that the contents of organic matter, total nitrogen, NO3-N, available phosphorus and available potassium in-creased by 38.46%, 11.39%, 4.75%, 11.02% and 18.69% in soils stacked or discharged biogas slurry and residue, compar-ison with the soils of none stacked or discharged, while the contents of total phosphorus and total potassium had no signifi-cant change. In the soil of greenhouse, the contents of organic matter, available phosphorus and available potassium in-creased by 16.16%, 12.30% and 6.28% in soil of stacked or discharged biogas slurry and residue comparison with the soils of not been stacked or discharged, and the contents of total nitrogen, total phosphorus, total potassium and NO3-N also had no significant change. In addition, the content of salt and Ph value of the 4 different soils did not change significantly. The products of biogas fermentation in pig farms could improve the fertility and quality of soil, however, more attention should be paid to the environmental issues and waste of resources induced by irrational use.%为解决中小规模养猪场沼气发酵产物的合理利用,调查了安康市107个养猪场对沼气发酵产物的利用现状,并分别采集了16家养猪场附近4种不同类型土壤,测定土壤养分及盐分含量.结果表明,各养猪场对沼气发酵产物中沼液和沼渣的利用率不足50％,就近堆、排放较为普遍.堆、排放沼渣和沼液耕地土壤有机质、全氮、硝态氮、有效磷、速效钾平均含量比未堆、排放耕地土壤分别增加了38.46％、11.39％、4.75％、11.02％、18.69％,对全磷和全钾含量影响不明显；在设施菜地施用沼液和沼渣土壤有机质、有效磷、速效钾平均含量比未施用的设施菜地土壤平均含量分别增加了16.16％、12.30％、6.28％,全氮、全磷、全钾及硝态氮含量变化不明显；对4种不同土壤类型土壤盐分含量及pH值均无明显影响.养猪场沼气发酵产物对提高土壤肥力,改善土壤性质有明显作用,不合理利用引起的资源浪费,以及由此带来的环境问题也值得关注.
展开▼
