长期不同施肥对黄泥田土壤酶活性和微生物的影响

以农业部耕地保育福建观测实验站的长期肥料试验为平台,研究了长期不同施肥对黄泥田土壤酶活性和微生物的影响。结果表明:与不施肥(CK)相比,单施NPK(NPK)、NPK配施牛粪(NPKM)及NPK配施秸秆(NPKS)的土壤酶活性均有不同程度的提高,其中NPKM可显著提高转化酶活性,NPKS可显著提高脲酶活性。施肥均不同程度地提高了土壤细菌、真菌及放线菌的数量,尤其是放线菌数量,提高幅度均达到显著性水平;NPKS可显著提高土壤细菌数量,NPKM可显著提高土壤真菌数量。施肥均会对真菌群落产生重要影响;单施化肥对土壤细菌群落的影响不大,增施有机物料会对细菌群落产生明显影响;施用牛粪会对放线菌优势群落产生影响。以上结果表明,有机无机配施更有利于提高土壤酶活性和土壤微生物数量,提升土壤生物肥力。

Effects of long-term different fertilization on soil enzyme activity and soil microbe in yellow paddy fields

A long-term(28 years)fertilizer experiment was carried out in the yellow paddy in Fujian Scientific Observing and Experimental Station of Arable Land Conservation,Ministry of Agriculture,China,to study effects of long term different fertilization systems on soil enzyme activity and soil microbe.The field experiment included four treatments:(1)unfertilized control(CK);(2)chemical fertilizers(NPK);(3)chemical fertilizers plus cattle manure(NPKM);(4)chemical fertilizer plus straw(NPKS).The results showed that compared with CK,the soil enzyme activities including hydrogen peroxidase,urease,invertase and phosphatase in all fertilization treatments were all increased more or less,and the invertase activities were significantly increased under the NPKM treatment,the urease activities were significantly increased under the NPKS treatment.The amount of soil microflora was also increased more or less in all fertilization treatments,especially the amount of actinomycetes showed a significant increase.Among the fertilization treatments(NPK,NPKM,NPKS),only NPKS led to a significant increase of soil bacterial amount,and only NPKM could significantly increase soil fungal amount.All fertilization treatments had important impacts on fungal community,compared with CK.However,chemical fertilizer alone had no influence on soil bacterial community,but organic amendment led to noticeable change.The dominant community of soil actinomycetes could be affected by the application of cattle manure.These findings indicated combined use of chemical fertilizers with manure or crop straw was better to raise soil enzyme activity and soil microbial amount,leading to enhancement of soil biological fertility.