不同施肥处理对连作蔗田土壤微生物量、土壤酶活性及土壤养分的影响

目的]阐明连作蔗田土壤的培肥效应,为建立合理的甘蔗施肥制度及提高连作蔗田土壤质量提供参考.方法]以连作甘蔗11年的赤红壤为研究对象,按不同施肥措施设单施化肥、单施有机肥、有机肥和化肥配施等8个处理,测定不同施肥处理对土壤微生物量、土壤酶活性及土壤相关肥力因子的影响.结果]不同施肥处理的土壤微生物量氮、碳、磷及土壤酸性磷酸酶、过氧化氢酶、蔗糖酶、脲酶活性均比对照增加.其中微生物量氮增加5.56％～67.13％、微生物量碳增加4.01％～20.40％、微生物量磷增加6.39％～67.02％;酸性磷酸酶活性提高12.96％～35.19％、过氧化氢酶活性提高18.24％～78.93％、蔗糖酶活性提高3.00％～42.00％、脲酶活性提高1.21％～23.43％;而不同施肥处理的土壤养分增加不显著(P＞0.05);土壤微生物量氮、碳、磷、酸性磷酸酶、过氧化氢酶、脲酶活性与速效磷、速效钾、全氮之间的相关性均达显著(P＜0.05)或极显著水平(P＜0.01).结论]以土壤微生物量和酶活性作为连作蔗田土壤培肥的评价指标更加全面和灵敏.

Effects of Different Fertilization Treatments on Soil Microbial Biomass,Soil Enzyme Activities and Related Nutrients in Continuous-cropping Sugarcane Field

Objective] This study was conducted to expound the fertility improvement effect in continuous-cropping sugarcane field and provide reference for establishment of rational sugarcane fertilization system and improvement of soil quality in continuous-cropping sugarcane field.Method] The soil in the experimental region is latosolic red soil which was planted with sugarcane for 11 years continuously,and 8 treatments including sole application of chemical fertilizers,sole application of organic fertilizer,and combined application of organic fertilizer and chemical fertilizers were designed according to different fertilization measures.The effects of different fertilization treatments on soil microbial biomass,soil enzyme activities and related fertility factors were determined.Result] Different fertilization treatments all showed soil microbial biomass N,C and P and activities of soil acid phosphatase,catalase,sucrase and urease higher than the CK.Soil microbial biomass N increased by 5.56％-67.13％,soil microbial biomass C increased by 4.01％-20.40％,and soil microbial biomass P increased by 6.39％-67.02％.The activity of acid phosphatase was improved by 12.96％-35.19％,the activity of catalase was improved by 18.24％ -78.93％,the activity of sucrase was improved by 3.00％-42.00％,and the activity of urease was improved by 1.21％-23.43％.However,the soil nutrients of different fertilization treatments increased non-significantly (P＞0.05).Soil microbial biomass N,C and P and activities of acid phosphatase,catalase and urease were in significant (P＜0.05) or very significant correlation (P＜0.01) with contents of soil rapidly available P,rapidly available K and total N.Conclusion] The evaluation of improvement of soil fertility in continuous-cropping sugarcane field using soil microbial biomass and enzyme activities as indexes is more comprehensive and sensitive.