枣苜间作对土壤养分及微生物的影响

Effects of Jujube-Alfalfa Intercropping on Soil Nutrients and Microorganisms

为了探讨枣树和苜蓿间作对土壤养分、微生物数量及多样性、作物产量的影响,在南疆干旱地区设计枣树和苜蓿间作、单作苜蓿及单作枣树3种种植模式,开展了田间试验。结果表明:与单作枣树相比,枣树和苜蓿间作土壤中全氮、全磷、全钾、速效磷及有机碳含量明显提升;与单作苜蓿相比,枣树和苜蓿间作土壤速效磷含量提高,全氮和有机碳含量降低;间作后土壤pH值降低。枣苜间作土壤真菌、放线菌数量均显著(P<0.05)高于其他2种种植模式,细菌变化不明显;枣苜间作土壤微生物多样性、均匀度指数均值分别比单作苜蓿提高了7.94%、8.23%,比单作枣树提高了28.65%、29.17%。枣苜间作条件下苜蓿产量为40820.00 kg/hm^(2),土地当量比为1.32,增产率为32.00%。说明枣树和苜蓿间作在改善土壤养分、提高土壤微生物数量及多样性、增加作物产量方面有积极作用,适宜在南疆干旱地区广泛应用。

In order to explore the effects of jujube and alfalfa intercropping on soil nutrients,quantity and diversity of microorganisms,and crop yield,field experiment was carried out by designing three planting patterns of jujube and alfalfa intercropping,alfalfa monoculture and jujube monoculture in the arid area of southern Xinjiang.The results showed that,compared with jujube monoculture,the contents of total nitrogen,total phosphorus,total potassium,available phosphorus and organic carbon in soil of jujube and alfalfa intercropping increased significantly.Compared with alfalfa monoculture,the content of soil available phosphorus in jujube and alfalfa intercropping increased,while the contents of soil total nitrogen and organic carbon decreased.Soil pH value decreased after intercropping.The number of fungi and actinomycetes in the soil of jujube and alfalfa intercropping was significantly higher than that of the other two planting patterns(P<0.05),however,the change of bacteria was not obvious.The average values of soil microbial diversity and evenness index of jujube and alfalfa intercropping increased by 7.94%and 8.23%respectively compared with alfalfa monoculture,and increased by 28.65%and 29.17%compared with jujube monoculture.Under the condition of jujube and alfalfa intercropping,the yield of alfalfa was 40820.00 kg/hm^(2),the LER was 1.32,the growth rate of intercropping was 32.00%.It showed that jujube and alfalfa intercropping played an active role in improving soil nutrients,increasing the quantity and diversity of soil microorganisms,and increasing crop yield,which was suitable for wide application in the arid areas of southern Xinjiang.