沼液的园林地消解处理利用及其对土壤微生物碳、氮与酶活性的影响

近年来,沼气工程发展迅猛,产生的大量沼液处理和排放问题日益突出,成为水环境保护中亟待解决的关键问题。为研究沼液灌溉园林地土壤进行消解处理利用过程对土壤微生物碳、氮及酶活的影响,提出沼液安全排放处理的新途径,通过在江苏宜兴万石镇葡萄园基地进行大田试验,比较了不同处理下沼液消解利用过程对土壤微生物碳、氮以及土壤微生物量碳与土壤有机碳的关系,并测定了土壤几种常见酶的活性。结果表明,沼液园林地（葡萄园）消解利用过程不会降低土壤微生物碳、氮含量,地面间作黑麦草或地下安装排水管道时能显著提高土壤微生物碳、氮含量,分别提高8.70%和17.34%。沼液园林地消解利用能提高土壤微生物量碳与土壤有机碳比率,但未达到显著性水平。沼液在园林地消解利用中,只进行沼液灌溉的处理区土壤蔗糖酶活性略微下降,其他试验区土壤蔗糖酶含量较对照区显著性提高,试验区土壤脲酶也较对照区提高了数倍以上,但土壤酸性磷酸酶和过氧化氢酶在该试验研究中未表现出较大变化。该试验仅为沼液消解处理利用的田间短期效应,沼液园林地消解利用处理对作物品质、土壤肥力和农业生产环境的综合影响仍需进行长期试验验证。

Short-term Effects of Biogas Slurry Application to Garden Land on Soil Microbial Biomass Carbon ＆ Nitrogen and Soil Enzymes

Due to the rapid development of biogas industries,large amount of biogas slurry was untreated and discharged randomly,which became a serious threat to the water safety.To study the effects of biogas slurry application to garden land on soil microbial biomass carbon（MBC）and nitrogen（MBN）,as well as enzymatic activities,we conducted the field experiment in a vineyard base in Wanshi Town of Yixing city,Jiangsu Province and proposed a new process to treat biogas slurry safely.The digestion and utilization process of biogas slurry was compared in different treatments to evaluate the relationship between MBC,MBN and soil organic carbon,and several enzyme activities were also determined.The results indicated that MBC and MBN were not decreased during the application of biogas slurry alone,whereas significantly increased 8.70% and 17.34%,respectively in the treatment with the intercrop of ryegrass（Lolium perenne L.）and the installation of belowground drainpipe.The ratio of MBC to soil organic carbon was impacted by the digestion and utilization process of biogas slurry,but did not reach a significant level.Soil sucrase activities were markedly improved in the treatment with the biogas slurry compared with CK（except the treatment with biogas slurry for irrigation alone）.Urease activities were considerably improved compared with CK,whereas the acidic phosphatase and catalase activities were not significant changed.In present experiment,the short-term effects of the utilization of biogas slurry in field condition were studied,and the integrated influence of the digestion and utilization of biogas slurry in garden land on crop quality,soil fertility and agricultural environment will be further investigated.