添加生物质炭对红壤性水稻土Cd^2+吸附解吸特性的影响  

Effects of Biochar Amendment on Adsorption and Desorption Characteristics of Cd^2+in Red Paddy Soil

作　　者：胡世民 陈效民[1] 景峰 杨之江 刘巍 温馨 HU Shimin;CHEN Xiaomin;JING Feng;YANG Zhijiang;LIU Wei;WEN Xin(College of Resource and Environment Science,Nanjing Agricultural University,Nanjing 210095)

机构地区：[1]南京农业大学资源与环境科学学院,南京210095

出　　处：《水土保持学报》2020年第2期360-364,371,共6页Journal of Soil and Water Conservation

基　　金：国家重点研发计划项目(2016YFD0800306)。

摘　　要：为探讨生物质炭对红壤性水稻土中镉(Cd)元素吸附解吸特性的影响,采用一次平衡法研究添加生物质炭后Cd2+在红壤性水稻土中的吸附动力学、等温吸附和解吸过程。结果表明:施用CK(0t/hm^2)、A10(10t/hm^2)、A20(20t/hm^2)、A30(30t/hm^2)和A40(40t/hm^2)生物质炭后,红壤性水稻土对Cd2+的吸附过程是以化学吸附为主、非均匀的多表面吸附。施用CK(0t/hm^2)、A10(10t/h2)、A20(20t/hm^2)、A30(30t/hm^2)和A40(40t/hm^2)生物质炭处理的最大吸附量和最大解吸量分别为2933~3346mg/kg和171~192mg/kg。添加生物质炭可以提高红壤性水稻土对Cd2+的吸附固持能力,同时增强土壤对外源Cd2+的缓冲能力。生物质炭添加量对红壤性水稻土的吸附解吸能力的改良效果具体表现为:A30>A40>A20>A10。高剂量的生物质炭处理使土壤吸附点位饱和,生物质炭吸附能力相对降低。因此,添加30t/hm^2生物质炭是一种有效预防和治理红壤性水稻土镉污染的措施。In order to investigate the effects of biochar on the adsorption and desorption characteristics of cadmium(Cd)elements,the adsorption kinetics,isothermal adsorption and desorption of Cd2+in red soil paddy soils amended with biochar were studied by a primary equilibrium method.The results showed that after applying biochar of CK(0 t/hm^2),A10(10 t/hm^2),A20(20 t/hm^2),A30(30 t/hm^2)and A40(40 t/hm^2),the adsorption of Cd2+in red paddy soil was dominated by chemical adsorption and heterogeneous multi-surface adsorption.The maximum contents of adsorption and desorption of each treatment were between 2933~3346 mg/kg and 171~192 mg/kg,respectively.The biochar enhanced the adsorption and fixation capacity for Cd2+in red paddy soil and improved the buffer capacity for Cd2+.The improvement of adsorption and desorption capacity in red paddy soil amended with biochar was shown as follows:A30>A40>A20>A10.High addition of biochar could saturate the soil adsorption point.Therefore,the adsorption capacity of biochar was relatively low.In conclusion,addition of 30 t/hm^2 biochar was the most reasonable measure.

关 键 词：生物质炭 动力学吸附 等温吸附 解吸 

分 类 号：S158[农业科学—土壤学] X53[农业科学—农业基础科学]