施肥对农田土壤碳氮磷化学计量特征及相关酶活变化的影响

Effects of Fertilization on the Stoichiometry of Carbon,Nitrogen and Phosphorus and Enzyme Activities in Agricultural System

归纳不同施肥条件下土壤养分和微生物量碳氮磷(CNP)化学计量特征及与之相关的酶活性变化,从施肥制度与土壤中养分平衡的关系着手制定出更加合理的施肥措施。通过数据整合分析,收集已公开发表施肥土壤中CNP化学计量比和酶活性变化的相关中、英文文献,提取有效数据,然后进行数据分析,通过绘制森林图明确土壤和微生物量CNP化学计量特征及土壤酶活变化对不同施肥方式的响应。结果表明:单一化肥、复合肥和化肥有机肥配施处理中C/N平均值分别为14.1,14.8和23.2,C/P分别为20.4,15.3和14.8,N/P分别为5.03,4.43和3.10。不同施肥措施下MBC/MBN和MBN/MBP无显著差异,MBC/MBP值排序为:化肥有机肥配施>单一化肥>复合肥。不同施肥制度均能提高土壤蔗糖酶、磷酸酶、脲酶和过氧化氢酶活性,其中化肥配施有机肥效果最为显著。化肥配施有机肥时蔗糖酶活性增幅可高达100%。化肥有机肥配施能够显著影响土壤中CNP化学计量比,增强微生物活动,促使微生物释放更多有利于土壤养分矿化的酶,是农业生产中提高作物产量并保证土壤健康的有效途径;土壤酶活性受到土壤肥力状况和微生物过程的共同制约,CNP化学计量比与土壤酶活性存在一定相关性,而这同时也受到土地利用类型、土壤酸碱度和轮作制度等因素的影响。土壤养分-微生物-酶活性体系的研究可以为农田系统优化施肥管理提供一定的理论依据。

Stoichiometry characteristics of soil CNP and MBC,MBN,MBP,and the changes of enzyme activity with different fertilization can help to understand the relationship between fertilization and soil nutrient balance,and thus formulate more reasonable fertilization measures.Published literature data on the changes of CNP status and enzyme activity in fertilized soil were collected,and the changes of CNP stoichiometry and enzyme activity in cultivated soil nutrient/biomass with different fertilization were analyzed by Meta-analysis.The results showed that the C/N under single fertilizer,compound fertilizer and the application of chemical fertilizer and manure was 14.1,14.8 and 23.2,the value of C/P was 20.4,15.3 and 14.8,the value of N/P was 5.03,4.43 and 3.10,respectively.There was no significant difference in MBC/MBN and MBN/MBP with different fertilization.The ratio of MBC/MBP was:application of fertilizer and manure>single fertilizer>compound fertilizer.Different fertilizations could improve the activities of soil sucrase,phosphatase,urease and catalase,especially the application of chemical fertilizer and manure(which increased urease activity by 100%).It showed that the application of chemical fertilizer and manure could significantly affected the stoichiometric ratio of CNP in soil,enhanced microbial activities and promoted microorganisms to release more enzymes conducive to soil nutrient mineralization.It was an effective way to improve crop yield and ensure soil health in agricultural production.Soil enzyme activity was restricted by soil fertility and microbial process.A certain correlation between CNP stoichiometric ratio and soil enzyme activity was observed,which was also affected by land use type,soil pH and rotation system.The study of soil nutrient-microorganism-enzyme activity system can provide a theoretical basis for optimizing fertilization management in farmland system.