不同气候条件对旱地红壤微生物群落代谢特征的长期影响

利用1988年设置的暖温带和中亚热带两种气候条件下的土壤置换试验,采用BIOLOG方法,研究了气候条件对红壤中微生物群落功能的影响。结果表明,长期处于不同的气候条件改变了红壤的pH和养分状况,从而影响红壤微生物群落的代谢特征。与中亚热带气候条件相比,暖温带气候条件下,红壤的pH和全磷含量显著升高,速效钾含量显著下降;红壤微生物群落活性(以AWCD值表示)也显著降低。主成分分析表明,不同气候条件下红壤微生物群落代谢特征显著不同,与暖温带气候相比,中亚热带气候条件下,红壤微生物群落对氨基酸、胺类和酚类化合物等含氮化合物的利用显著增加。相关分析表明,影响不同气候条件下红壤微生物代谢特征的主要因素有:温度和降雨量气候因子,土壤pH、速效钾和全氮含量等土壤因子。

Long-term effects of different climatic conditions on microbial metabolic properties in red soil

To study the impact of climatic conditions on soil microbial metabolic properties, a transplant experiment of red soil was conducted in the warm temperate and mid-subtropical zone of East China. Soil microbial communities were measured by BIOLOG ECO plate. The results showed that the climatic conditions affected soil pH and nutrient contents, and then affected soil microbial metabolic properties. From warm temperate to mid-subtropical climate, soil pH and total P contents decreased significantly, soil available K contents increased significantly, soil microbial community activity (expressed as AWCD) also increased significantly. Principal component analysis of soil microbial communities showed there was significant difference in the metabolic fingerprints of soil microbial communities in red soil among different climatic conditions. Amino acid, amines and phenolic ethylamine were much more to be utilized by red soil microorganism in middle subtropical climate compared with warm temperate climate. Correlation analysis of soil microbial communities and soil nutrient contents showed that temperature and rainfall, soil pH, total N and available K contents are the influential factors of soil microbial metabolic properties.