不同生物质炭对棕壤中磷素吸附解吸的影响  

Effects of Different Biochars on Phosphorus Adsorption and Desorption in Brown Soil

作　　者：刘慧[1] 张伟康 李蒋戈野 王青青 承睿 张少斌[2] LIU Hui;ZHANG Weikang;LI-JIANG Geye;WANG Qingqing;CHENG Rui;ZHANG Shaobin(College of Land and Environment,Shenyang Agricultural University,Shenyang 110866,China;College of Biological Science and Technology,Shenyang Agricultural University,Shenyang 110866,China)

机构地区：[1]沈阳农业大学土地与环境学院,沈阳110866 [2]沈阳农业大学生物科学技术学院,沈阳110866

出　　处：《土壤》2023年第6期1198-1206,共9页Soils

基　　金：国家自然科学基金项目(41671293);沈阳农业大学大学生创新创业训练计划项目(2022167,2022265)资助。

摘　　要：为了减少土壤磷素流失,提高磷肥利用效率,探究不同生物质炭对棕壤中磷素吸附解吸行为的影响规律,以水稻秸秆、玉米秸秆和花生壳为原材料,利用限氧升温炭化法制备生物质炭,通过批量吸附试验研究了生物质炭种类和生物质炭添加量对棕壤磷吸附解吸的影响。结果表明:水稻秸秆生物质炭在添加量为4 g/kg时显著提高棕壤对磷的吸附量,花生壳生物质炭和玉米秸秆生物质炭则显著降低棕壤对磷的吸附量;吸附等温线表明,不同生物质炭均未改变吸附等温线的变化趋势,均可用Langmuir方程和Freundlich方程进行描述(R^(2)>0.93),其中Langmuir方程拟合效果更好,不同处理对磷的理论吸附量大小顺序为:水稻秸秆生物质炭+棕壤>棕壤>花生壳生物质炭+棕壤>玉米秸秆生物质炭+棕壤;吸附动力学试验表明,不同生物质炭均未改变磷吸附动力学曲线的变化趋势,在所有动力学模型中,准二级动力学模型最适合描述土壤对磷的吸附行为(R^(2)>0.99),其次为准一级动力模型(R^(2)>0.99)和Elovich动力学模型(R^(2)>0.88);3种生物质炭均显著促进棕壤对磷的解吸,当生物质炭添加量为≥2g/kg时,水稻秸秆生物质炭、玉米秸秆生物质炭和花生壳生物质炭,分别可提高棕壤对磷的解析率50%、70%和90%以上。由此可见,不同生物质炭可提高棕壤对磷素的供应和利用,水稻秸秆生物质炭在减少棕壤磷素流失、保护生态环境方面具有更大的应用价值。In this study,different biochars were prepared with rice straw,corn straw and peanut shell using the oxygen-limiting heating carbonization method and their influences on phosphorus(P)adsorption and desorption in brown soil were studied through batch adsorption experiment in order to reduce the loss of soil P and improve the utilization efficiency of P fertilizer.The results showed that rice straw biochar significantly improved P adsorption with an addition of 4 g/kg,while peanut shell and corn straw biochars significantly reduced P adsorption.The change trend of isothermal adsorption curves were similar under different biochars,all could be described well by Langmuir and Freundlich equations(R^(2)>0.93),among them,Langmuir equation fitted better.P maximum theoretical adsorption caused by different treatments was as follows:rice straw biochar+brown soil>brown soil>peanut shell biochar+brown soil>corn straw biochar+brown soil.The adsorption kinetic experiments showed that the trend of P adsorption kinetic curve did not change under different biochars,among all kinetic models,the quasi-secondary kinetic model was the best suitable to describe P adsorption behavior(R^(2)>0.99),followed by the quasi-first-order kinetic model(R^(2)>0.99)and Elovich kinetic model(R^(2)>0.88);The three kinds of biochars significantly promoted P desorption of brown soil,when biochar addition was≥2 g/kg,rice straw,corn straw and peanut shell biochars could improve P desorption rate by 50%,75%and 90%,respectively.In conclusion,different biochars can improve P supply and utilization of brown soil,and rice straw biochar has greater application value in reducing P loss of brown soil and protecting the ecological environment.

关 键 词：棕壤 生物质炭 磷 吸附解吸 

分 类 号：S156.2[农业科学—土壤学]