摘要
为研究富硅材料谷壳灰(HA)对稻田土壤Cd、As生物有效性及糙米中Cd、As累积的影响,以稻壳为原料制备中性HA(总硅量6.26×10^5 mg·kg^-1),开展水稻盆栽试验.HA按质量比设置4个添加水平(0、0.5%、1%、2%),种植3种水稻(黄华占、湘晚籼13、隆优4945).研究结果表明:①在土壤Cd总量为2.30 mg·kg^-1、As总量为90.45 mg·kg^-1的复合污染土壤中,HA施用后,与对照相比,土壤Cd的TCLP提取态、CaCl2提取态及酸可提取态含量呈现不同程度的降低,分别降低了7.8%~18.7%、7.4%~18.7%、0.9%~16.7%;土壤As的交换态和TCLP提取态含量也有降低,分别降低了6.1%~47.1%、4.3%~26.7%.②HA施用可促进土壤中酸可提取态Cd向难溶态Cd的转变,水稻湘晚籼13、隆优4945根际土壤残渣态Cd含量分别增大9.8%~23.5%、5.9%~28.1%;土壤中As主要以残渣态存在,HA的施用对土壤专性吸附As含量有增大效应.③HA施用能够降低糙米中Cd和无机As含量,施用0.5%~2%HA能使水稻隆优4945和湘晚籼13糙米Cd含量降低到0.2 mg·kg^-1以下,施用2%HA能使黄华占糙米无机As含量降低到0.2 mg·kg^-1以下.施用HA能够有效降低土壤Cd、As生物有效性和糙米Cd、As含量,同时增大土壤有效Si含量,有利于提高土壤质量.
Rice pot experiments were conducted with application of silicon⁃rich material husk ash HA(total silicon concentration 6.26×10^5 mg·kg^-1)to study the influences of HA on cadmium(Cd)and arsenic(As)bioavailability and their accumulation in brown rice in complexly contaminated paddy soil with Cd(2.30 mg·kg^-1)and As(90.45 mg·kg^-1).HA was set at four levels(0,0.5%,1%,2%,W/W)based on the quality ratio,and three genotypes of rice were planted(Huanghuazhan,Xiangwanxian 13,Longyou 4945).The results showed that:①Compared with the control treatment,HA decreased the concentrations of soil TCLP⁃Cd,CaCl2⁃Cd and HOAc⁃Cd by 7.8%~18.7%,7.4%~18.7%,0.9%~16.7%,respectively.HA application decreased the concentrations of TCLP⁃As and NH4Cl⁃As in different degrees by 6.1%~47.1%and 4.3%~26.7%,respectively.②Application of HA promoted transformation of soil Cd from acidic extractable to insoluble,thus increasing the residual Cd in the rhizosphere soils of rice Xiangwanxian 13 and Longyou 4945 by 9.8%~23.5%and 5.9%~28.1%,respectively.As in soil mainly existed in the form of residues,and the application of HA had an increasing effect on the specific adsorption of As.③Application of HA could reduce concentrations of Cd and inorganic As in brown rice.When 0.5%~2%of HA was applied,Cd concentrations in brown rice were lower than 0.2 mg·kg^-1 for Xiangwanxian 13 and Longyou 4945;when 2%of HA was applied,concentration of inorganic As in brown rice was lower than 0.2 mg·kg^-1 for Huanghuazhan.Application of HA could effectively reduce the bioavailability of Cd and As in soil and the concentrations of Cd and inorganic As in brown rice,and increase available Si concentration in soil,which is beneficial to improvement of soil quality.
作者
刘雅
辜娇峰
周航
邓鹏辉
霍洋
黄芳
张竞颐
廖柏寒
LIU Ya;GU Jiaofeng;ZHOU Hang;DENG Penghui;HUO Yang;HUANG Fang;ZHANG Jingyi;LIAO Bohan(College of Environment Science and Engineering,Central South University of Forestry and Technology,Changsha 410004;Hunan Engineering Laboratory for Control of Rice Quality and Safely,Changsha 410004)
出处
《环境科学学报》
CAS
CSCD
北大核心
2020年第7期2581-2588,共8页
Acta Scientiae Circumstantiae
基金
湖南省自然科学基金(No.2018JJ3880)
国家自然科学基金青年科学基金(No.41907126)
中南林业科技大学引进人才科研启动基金(No.2019YJ041)。
关键词
镉
砷
糙米
谷壳灰
土壤
生物有效性
cadmium
arsenic
brown rice
husk ash
soil
bioavailability
