不同来源生物炭对土壤磷吸附解吸的影响  

Effect of Biochar of Different Sources on Adsorption and Desorption of Phosphorus in Soil

作　　者：李仁英 吴洪生 黄利东 张朴 杨江俐 周皓然 石婕 潘仕球 张宇 王金晓 

机构地区：[1]南京信息工程大学应用气象学院农业资源与环境系,江苏南京210044 [2]江苏省农业气象重点实验室,江苏南京210044 [3]土壤与农业可持续发展国家重点实验室(中国科学院南京土壤所),江苏南京210008

出　　处：《土壤通报》2017年第6期1398-1403,共6页Chinese Journal of Soil Science

基　　金：江苏省自然科学基金项目(BK20141479);国家自然科学基金项目(41001190);十二五环保科技重大水专项子课题项目(2015ZX07204-002);土壤与农业可持续发展国家重点实验室项目(Y052010018);南京信息工程大学大学生实践创新训练共同资助

摘　　要：主要研究了水稻秸秆、小麦秸秆、玉米秸秆、花生壳四种来源的生物炭对土壤磷吸附解吸的影响。研究结果表明:生物炭对土壤磷吸附的影响取决于土壤溶液中磷的浓度,与对照相比,在中低磷浓度(0~90 mg L-1)时,四种生物炭对土壤磷的吸附影响较小,而在较高磷浓度时,小麦秸秆生物炭和花生壳生物炭均抑制了土壤磷的吸附,而水稻秸秆生物炭和玉米秸秆生物炭均能促进土壤磷的吸附。吸附动力学试验表明,在反应开始的4小时内,土壤对磷的吸附较快,吸附量基本达到平衡吸附量的50%;到达吸附平衡时,添加生物炭能够降低土壤对磷的吸附量,四种生物炭对土壤磷的吸附量依次为:小麦秸秆>玉米秸秆>花生壳>水稻秸秆。此外四种生物炭都能促进土壤中磷的解吸,其中玉米秸秆的促进效果最为显著,解吸量比对照高1.76倍。Langmuir方程和Freundlich方程都能很好地拟合生物炭存在下土壤磷的吸附等温线(P<0.01),Freundlich拟合程度要比Langmuir方程的高。准一级动力学方程和准二级动力学方程都能很好地描述生物炭存在下土壤磷的吸附动力学(P<0.01)。Effects of biochars derived from rice straw,wheat straw,maize straw and peanut shell on the adsorption and desorption behaviors of phosphorus in soil were studied in this experiment.The results showed that effects of biochars on adsorption of phosphorus depended on phosphorus concentration in soil solution.Compared with the control,the effect of biochars on adsorption of phosphorus was small when phosphorus concentration was lower than 90 mgL^-1.However,adsorption of phosphorus was inhibited by biochars derived from wheat straw and peanut shell and was promoted by biochars derived from rice straw and maize straw,when phosphorus concentration was high in soil solution.Addition of biochars to soil decreased adsorption amount of phosphorus under the condition of equilibrium and adsorption amount followed the order：wheat straw biocharmaize straw biocharpeanut shell biocharrice straw biochar.The four kinds of biochar promoted desorption of phosphorus from soil.Desorption amount of soil phosphorus with maize straw biochar added was 1.76 times higher than that of control.Adsorption isotherm of phosphorus could be well described by Langmuir equation and Freundlich equation（P〈0.01）.Adsorption kinetics of phosphorus could be well described by pseudo-first-order kinetics and pseudo-second order kinetics equation（P〈0.01）.

关 键 词：土壤 生物炭 磷元素 吸附 解吸 

分 类 号：S156.2[农业科学—土壤学]