畜禽粪肥添加及干湿交替强度对土壤微生物功能多样性的影响

Effects of livestock and poultry manure amendment and wetting-drying cycle on functional diversity of soil microbial community

水肥管理是农业土壤田间管理的重要措施,对农业土壤质量和生态稳定性具有重要的影响。以长期施用化肥的稻麦轮作低有机碳含量的犁底层土壤为供试土壤,通过设置添加畜禽粪肥处理和干湿交替强度处理的室内培养实验,研究水肥管理对土壤微生物群落功能多样性的影响。结果表明,添加畜禽粪肥显著提高了土壤微生物群落对碳源的利用能力,添加鸡粪肥和猪粪肥处理土壤总AWCD值分别为空白对照的4.5倍和5.9 倍;土壤微生物群落丰富度指数、辛普森指数和香农指数均显著高于对照。干湿交替强度对微生物群落功能多样性也产生了明显影响,表现出对土壤微生物群落功能多样性的激发作用,其中强干湿交替最为明显。因子分析、对应分析和聚类分析结果表明,添加畜禽粪肥是土壤微生物群落功能多样性变化的主控因子,而干湿交替胁迫是第二控制因子。综合分析结果表明,添加畜禽粪肥和干湿交替主要是通过改变土壤中碳水化合物和氨基酸类碳源等影响土壤微生物群落功能多样性。

Water and fertilizer management is one of important measures in agricultural field management,it may control the quality and ecological stability of agricultural soil. In this study,the tested soil samples were taken from the plough-pan of a rice and wheat rotation agricultural system with long-term application of chemical fertilizer.The organic carbon content of tested soil was poor. Incubation experiment was established with the amendment of livestock and poultry manure and the intensity of wetting-drying cycle,to understand the effects of water and organic fertilizer management on soil microbial community functional diversity. Results showed that livestock and poultry manure amendment significantly improved the carbon using ability of soil microbial community. The soil AWCD value with poultry manure and livestock manure treatment was 4.5 and 5.9 times higher than that in control soil respectively;Richness index,Simpson index and Shannon index of soil microbial community were significantly higher than those of control. Wetting-drying cycle intensity also had a significant influence on soil microbial community functional diversity,showing the priming effect on soil microbial community functional diversity. And the strong wetting-drying cycle had the most obvious effect on it. Results of factor analysis,correspondence analysis and cluster analysis showed that livestock and poultry manure amendment was the main control factor on soil microbial community function diversity,while the wetting-drying cycle was the second control factor. The results indicated that the combined effect of livestock and poultry manure amendment and wetting-drying cycle could influence the functional diversity of soil microbial community by changing the carbohydrate and amino acid carbon source in soil.