摘要
选择长江三角洲地区代表性人为耕作土壤小粉土和黄红壤为研究对象,通过网室盆栽试验研究了水旱轮作下小粉土和黄红壤汞污染的微生物和酶活性的变化。结果表明:收获水稻后和收获青菜后土壤微生物和酶活性变化的共同点是,随Hg处理浓度增加,土壤微生物量碳、呼吸强度、代谢商、土壤酶活性(脲酶、酸性磷酸酶、脱氢酶)均表现为先上升后下降,其峰值浓度因土壤类型、土壤酶类型和栽培作物种类不同而不同。收获水稻后和收获青菜后土壤微生物和酶活性变化的不同点是:土壤类型相同,除代谢商外,水稻收获后的土壤微生物量碳、土壤呼吸强度、土壤酶活性均高于青菜收获后的;栽培作物相同,除呼吸强度和代谢商外,黄红壤的土壤微生物量碳和土壤酶活性均高于小粉土的;与栽培作物类型无关,小粉土酶活性的变异系数明显大于黄红壤。
Two representative soils for rice production in China,locally referred to as yellowish red soil（YRS） and silty loam soil（SLS）,and classified as Gleyi-Stagnic Anthrosols in FAO/UNESCO nomenclature,were respectively collected from Deqing county and Huajiachi campus,Zhejiang university of Hangzhou city,Zhejiang province.Both laboratory and greenhouse pot experiments using rice and Chinese cabbage as indicator plants were conducted to investigate mercury ecological dose responses of microbial biomass carbon,basal respiration,metabolism quotient,and some important soil enzymes including urease,dehydrogenase,and acid phosphatase,which are related to cycling of soil C,N and P in the YRS and SLS soil at Hg2＋ loadings of 0,0.25,0.5,1,1.5,2,3,6 mg/ kg after harvesting rice and Chinese cabbage.The similarities of microbial and enzymatic activities of paddy soils after harvesting rice or Chinese cabbage were that all measured microbial and enzymatic indices increased with the increasing level of Hg treatments at low concentrations and decreased at high concentrations.Its peak values depended on soil types,soil enzymes types and crop kinds.Their differences were that microbial biomass carbon,basal respiration and enzymatic activities of paddy soil except for metabolism quotient after harvesting rice were higher than after harvesting Chinese cabbage under the same soil types;microbial biomass carbon and enzymatic activities of YRS except for basal respiration and metabolism quotient were higher than theirs of SLS under the same crop kinds;Variation coefficient of enzymatic activities of SLS which weren＇t related to crop kinds was bigger than its of YRS.
出处
《水土保持学报》
CSCD
北大核心
2010年第3期180-184,共5页
Journal of Soil and Water Conservation
基金
国家基础研究发展规划项目(2002CB410804)
国家杰出青年科学基金(40025104)
关键词
汞
稻菜轮作
微生物活性
酶学活性
mercury
rice-Chinese cabbage rotation system
microbial activity
enzymatic activity
