增温水灌溉对棉花根际土壤养分和土壤微生物数量的影响

摘要

[目的]通过田间增温水灌溉(ZW)和井水灌溉(CK)小区实验,研究滴灌温度对棉花根际土壤养分及微生物数量的影响.[方法]在膜下滴灌条件下,设置增温滴灌和井水滴灌2水平3重复处理,在棉花蕾期、铃期时采集棉花根际0～20 cm土壤,测定土壤速效N、有效P、速效K及有机质含量,并在蕾期时取完整灌水周期中根际土壤鲜样测定土壤细菌、真菌、放线菌数量.[结果] 蕾期时ZW处理土壤速效氮含量较CK减少13.51％(P0.05);完整灌水周期内ZW处理土壤微生物数量均有所增加,其中灌水后第3 d,细菌、真菌、放线菌分别增加了41.5％(P放线菌>真菌.[结论]增温水灌溉可以促进棉花对土壤养分的吸收,降低土壤中养分含量,亦可丰富土壤中微生物总量,促进土壤养分循环转化.%[Objective] This project aims to explore the effects of drip irrigation temperature on soil nutrients and soil microbial biomass in cotton rhizosphere by the field experiment of temperature-increasing water irrigation(ZW)and well water irrigation(CK).[Method]This experiment set a water warming irrigation and well irrigation of 2 levels and 3 repeats with drip irrigation under plastic film to research the content of cotton rhizosphere soil available N,available P,available K and organic matter during cotton bud stage and boll stage,and collected the rhizosphere fresh soil within the depths of 0-20 cm to detect soil bacteria,fungi,actinomycetes number in complete irrigation cycle during the bud stage.[Result]The result showed that in the bud stage,soil available N content by ZW treatment was reduced by 13.51％(P0.05).The number of soil microorganisms by ZW treatment was increased during the single irrigation period.Three days after irrigation,bacteria,fungi and actinomycetes were increased by 41.5％(P actinomycetes > fungi.[Conclusion]Water warming irrigation can not only promote the absorption of soil nutrients in cotton,thus reducing the nutrient content in soil,but also enrich the amount of microorganism in soil and accelerate soil nutrient cycling.