生物复混肥对土壤微生物群落功能多样性和微生物量的影响

在温室盆栽条件下,采用Biolog微平板法和氯仿熏蒸浸提法,研究了玉米施用等养分量的无机肥、有机无机复混肥和生物复混肥后土壤微生物群落功能多样性及土壤微生物量的变化。结果表明:生物复混肥处理的土壤微生物平均颜色变化率(AWCD)、微生物群落Shannon指数(H)和微生物群落丰富度指数(S)均最高;施用生物复混肥可明显提高土壤微生物对碳源的利用率,尤其是多酚化合物类和糖类;不同处理土壤微生物碳源利用特征有一定差异,生物复混肥在第1主成分上的得分值为正值,其他各处理在第1主成分上的得分值基本上为负值,起分异作用的主要碳源是糖类和羧酸类。在玉米生长期间各处理土壤微生物量大致呈先升高后逐渐平稳的趋势,且土壤微生物量碳、氮、磷的含量均以生物复混肥处理最高,最高值分别为333.21mg.kg 1、53.02 mg.kg 1和22.20 mg.kg 1。研究表明,生物复混肥的施用比等养分量的有机无机复混肥处理能显著提高土壤微生物群落碳源利用率、微生物群落丰富度和功能多样性,显著增加土壤微生物量碳、氮、磷的含量,有利于维持良好的土壤微生态环境。

Effects of bio-compound fertilizer on soil microbial communityfunctional diversity and microbial biomass

The characteristics of soil microbes are sensitive indicators for soil fertility. Fertilization could influence soil physiochemical and biological properties. This study illustrated the functions of bio-compound fertilizers in maintaining good soil micro-ecological environment using the Biolog ECO micro-plate technique and CHCl3 fumigation-extraction method. The study investigated the effects of bio-compound fertilizer, organic-inorganic compound fertilizer and inorganic fertilizer at equal N, P and K amounts on functional diversities of soil microbial communities and microbial biomass under short-term potted corn experiment in greenhouse conditions. The six types of substances that composed Biolog ECO plate substrates included carbohydrates, carboxylic acids, amino acids, polymers, amines and aromatic chemicals. Principal Component Analysis (PCA) depicted different utilization forms of resource carbon by soil microbes. Average well-color development (AWCD), Shannon index (H) and richness index (S) of soil microbe communities were the highest in bio-compound fertilizer treatment. Bio-compound fertilizers obviously increased microbial source carbon utility, especially those of aromatic chemicals and carbohydrates. A significant difference existed in metabolic ability of soil microorganisms under different fertilizer treatments. Bio-compound fertilizer score was positive for the first principal component, while other treatments scores were negative. The determinant carbon sources for the differences were carbohydrates and carboxylic acids. During corn growth period, soil microbial biomass increased gradually and then stable with time. The amounts of soil microbial biomass C (333.21 mg?kg^-1), N (53.02 mg?kg^-1) and P (22.20 mg?kg^-1) were highest under bio-compound fertilizer treatment. At the same nutrient rates, bio-compound fertilization significantly improved utilization rates of carbon source, richness indexes and functional diversities of soil microbial community. This also increased the amounts of soil microbial biomass C, N and P.