红枫湖流域枯水期土壤理化特征与磷素分异研究  

Physical-chemical Characteristics and Phosphorus Distribution in Soils from the Lake Hongfeng Watershed in Dry Seasons

作　　者：张润宇[1] 王立英[1] 陈敬安[1] 

机构地区：[1]中国科学院地球化学研究所环境地球化学国家重点实验室,贵阳550002

出　　处：《地球与环境》2014年第6期719-725,共7页Earth and Environment

基　　金：国家自然科学基金(41273151;41273148);贵阳市科技计划项目(筑科合[2012103]86号);贵州省省长专项资金项目(黔省专合字[2012]7号)

摘　　要：对贵州省红枫湖枯水期流域土壤的理化性质、磷素含量与形态分布进行了初步研究。结果表明,土壤偏酸性,以粉砂粒为主,消落带土样含水率略高于林地和荒地。表土全磷和速效磷含量为99.6~679.5mg/kg和1.1~18.6mg/kg,低于我国土壤平均水平,属喀斯特地质性缺磷;最高值分布在受人类活动污染严重的管理处和后午,且随土层深度的增加而降低。土壤中不同磷形态的含量顺序为Residual-P〉NaOH-P〉HCl-P〉NaHCO3-P〉H2O-P。其中,耕作土壤中有机碳、全氮、全磷和速效磷含量,以及H2O-P、NaHCO3-P和总可提取态磷的比例均显著高于荒地和林地,表明耕作与施肥过程不仅提高了土壤全磷和生物活性磷含量,也加剧了水土流失的环境风险。Physical-chemical properties,contents and form distribution of phosphorus（P）in soils from the Lake Hongfeng Watershed were investigated during a drought period.The results showed that soil was acidic,with silt-dominating particle size composition.Water contents were slightly higher in soils from the water-level-fluctuating zone than those of abandoned land.Due to P deficiency in karst geological areas,total P and available P were below the national average level,ranging from 99.6to 679.5mg/kg and from 1.1to 8.6mg/kg in top soils of the Lake Hongfeng Watershed.The highest values of total P and available P occurred in soils of management office and Houwu with heavy human activities,and gradually reduced with increasing soil depth.Soil P forms varied in the rank order of Residual-PNaOH-PHCl-PNaHCO3-PH2O-P.The contents of organic carbon,total nitrogen,total P and available P,the proportions of H2O-P,NaHCO3-P and total extractable P were significantly higher than those of forest land and abandoned land,suggesting that the cultivation and fertilization processes have not only improved the contents of total and bio-available P,but also enhanced soil loss risk on the water environment.

关 键 词：红枫湖流域 土壤 磷 农业面源污染 

分 类 号：S153[农业科学—土壤学]