猪粪好氧堆肥对缺锌土壤种植大豆的影响研究

以Zn含量较高的猪粪为原料进行了90d好氧堆肥,以采自陕西省永寿县养马庄的典型缺锌土壤为供试土样,通过大豆盆栽试验研究了该有机肥对大豆生长的影响,并以污染指数评价法和地积累指数评价了施用该有机肥对土壤中重金属的累积环境风险。结果表明:经过90d的高温好氧堆制,获得了氮磷钾丰富的堆肥产品,且堆肥中未检测出Ni、Cd、Cr、Pb、Hg和As等有害重金属,仅含Cu256.3mg.kg-1、Zn474.4mg.kg-1。与对照相比,随着有机肥施用量的增加,大豆生物量和产量逐渐增加,并在肥土比10%时达到最高,大豆产量比对照提高了206.7%,大豆根系重量提高了94.2%,大豆茎叶(含荚壳)提高了94.0%;大豆籽粒中Zn含量则随着有机肥施用量的增加而逐渐增加,并在40%时籽粒Zn含量高达49.33mg.kg-1;施用堆肥后,土壤EC、Zn和Cu全量、Zn和Cu有效量均随着堆肥使用量的增加而增加,而土壤pH则随着堆肥比例的增加,从8.46逐渐降低到7.44。污染指数评价法和地积累指数评价法表明,当茬堆肥施用量不超过5%时,不会对该缺锌土壤造成重金属污染。研究显示,适量施用该堆肥能显著促进大豆的茎叶和根系生长,同时提高籽粒产量和籽粒中的Zn含量。对于供试缺锌土壤,施用该富锌有机肥可以明显补充土壤锌。

Influence of Swine Compost Application on the Soybean Planting and Its Environmental Risk Assessment

In order to study the effect of compost application on soybean planting in a typical zinc lack soil which was collected from Yangmazhuang,Yongshou County,Shaanxi Province.High zinc contained swine manure was selected as the raw materials and the corn stalk powder as the amendment,the mixture was composted for 90 days in an aerobic reactor.The effects of different amount of compost on growth and development,yield and quality of soybean through pot cultivating experiment were studied.The results showed that after 90 days composting,the final organic fertilizer contained plenty of N,P,K,as well as Cu 256.3 mg.kg-1 and Zn 474.4 mg.kg-1,respectively,the elements such as Ni,Cd,Cr,Pb,Hg and As were out of determination.The organic fertilizer had significant effect on the soybean seed yield,stem and root growth,as well as seeds Zn content increase.And the seed,stem and root weight reached the maximum amount with the compost ratio increased to 10%,and compared with the control treatment,soybean seed weight,root weight and stem(including pod shell)increased 206.7%,94.2% and 94.0%,respectively.Zn content in seed increased with the amount of compost added,and was as high as 49.33 mg.kg-1 in 40% compost ratio.Along with the increase of the proportion of compost,soil EC,total Zn and Cu,available Zn and Cu content increased rapidly,while the soil pH gradually declined from 8.46 to 7.44.The further single pollution index and geoaccumulation index evaluation results indicated that it would not cause the typical zinc lack soil environmental risk with the compost rational application rate of 5%.And the compost rational application rate in Yongshou zinc lack soil was 90.28 t.hm-2.a-1 which could be used for 20 years.The study implicated that the high zinc content swine manure compost had a potential agricultural application value in the zinc lack soil,and it had a positive effect on the soybean planting with the compost rational application rate of 5%.