摘要
采用室内培养实验测定了4种低分子量有机酸在低浓度(4 mmol·kg^(-1)干土)、中浓度(20 mmol·kg^(-1)干土)和高浓度(100 mmol·kg^(-1)干土)梯度下,对土壤微生物数量、呼吸强度和土壤酶活性的影响规律.结果表明,随着有机酸浓度的升高,甲酸、草酸和柠檬酸处理的土壤细菌数量和呼吸强度持续升高,真菌数量持续降低,放线菌数量在低浓度被促进,中浓度和高浓度被抑制;苯甲酸则表现出了与前3种有机酸不同的规律,土壤真菌数量持续升高,而土壤细菌、放线菌数量和土壤呼吸强度则表现了低浓度升高而后不断降低的特点.对于土壤酶活性而言,甲酸处理的淀粉酶、脲酶和磷酸酶活性和苯甲酸处理的土壤过氧化氢酶、脱氢酶和土壤肥力生物指数(BIF)在低浓度升高,而在中浓度和高浓度降低;甲酸处理的过氧化氢酶、脱氢酶和BIF,草酸处理和柠檬酸处理的蛋白酶、脱氢酶、土壤酶活性指数(EAN)、BIF,苯甲酸处理的蛋白酶和脲酶活性呈现随着有机酸浓度的升高而持续上升的趋势.综合土壤微生物数量、土壤呼吸和土壤酶活性,对土壤生态质量而言,在低浓度时苯甲酸处理最高,中浓度时柠檬酸处理最高,而在高浓度时草酸处理最高.
Effects of 4 low molecular weight organic acids with low(4 mmol·kg^-1 dry soil), medium(20 mmol·kg^-1 dry soil) and high concentration(100 mmol·kg^-1 dry soil) on soil microbe number, respiration intensity and enzyme activities were investigated by indoor culture experiments. The results showed that with increasing concentration, soil bacteria number and respiration intensity of formic acid, oxalic acid and citric acid treatments were continuously elevated, and soil fungi number was continuously decreased, while actinomycete number was increased at low concentrations and reduced at medium and high concentrations. Soil microbe number and respiration intensity of benzoic acid treatment showed a pattern different from that of the above three organic acid treatments.Soil fungi number was increased with increasing concentration, and soil bacteria number, actinomycete number and respiration intensity was increased at low concentrations and decreased at medium and high concentrations. Soil amylase, urease, phosphatase activities of formic acid treatment as well as catalase, dehydrogenase activities and biological fertility of soil(BIF) of benzoic acid treatment were enhanced at low concentrations and reduced at medium and high concentrations. Catalase, dehydrogenase, BIF of formic acid treatment, protease, dehydrogenase, enzyme activity number(EAN), BIF of both oxalic acid and citric acid treatment, protease, urease of benzoic acid treatment showed a continuously increasing trend with increasing concentration. Soil ecological quality of benzoic acid treatment at low concentrations, citric acid treatment at medium concentrations and oxalic acid at high concentrations were the highest.
出处
《环境化学》
CAS
CSCD
北大核心
2016年第2期348-354,共7页
Environmental Chemistry
基金
辽宁省自然科学基金(2015020805)
辽宁省科学事业公益研究基金(2015002011)资助~~
关键词
低分子量有机酸
土壤微生物数量
土壤呼吸强度
土壤酶活性
low molecular weight organic acid, soil microbe number, soil respiratory intensition, soil enzyme activities.