南方酸性红壤区5种典型土地利用土壤Pb、Cu的吸附解吸特征  

Pb and Cu Adsorption-desorption Characteristics of Five Typical Land Use Soils in Acid Red Soil Zone of South China

作　　者：李灵[1] 唐辉[2] 张玉[3] 陈达英[1] 王涛[1] 邱炎坤 

机构地区：[1]福建省生态产业绿色技术重点实验室,武夷学院生态与资源工程学院,武夷山354300 [2]陕西理工大学外国语学院,汉中723003 [3]武夷学院土木工程与建筑学院,武夷山354300

出　　处：《科学技术与工程》2017年第5期126-131,共6页Science Technology and Engineering

基　　金：南平市科技局项目(N2009Z10-3);武夷学院对接南平产业发展专项(2011DJ08);武夷山风景名胜区管理委员会项目(2008-03)资助

摘　　要：研究了南方酸性红壤5种典型土地(马尾松、杉木、竹林、茶园、稻田)利用的土壤对Cu、Pb的吸附-解吸特性。结果表明,(1)在Pb^(2+)、Cu^(2+)最大初始浓度(100 mg·L^(-1))条件下,Pb、Cu的吸附量表现为稻田(2 254.35、1 254.63 mg·kg^(-1))﹥杉木林(2 237.33、732.81 mg·kg^(-1))﹥马尾松林(2 010.66、581.94 mg·kg^(-1))﹥竹林(1 730.47、470.56 mg·kg^(-1))﹥茶园(1 574.01、322.69 mg·kg^(-1)),这与土壤中有机质和阳离子交换量(Cation exchange copaeifg,CEC)大小顺序一致。(2)Cu和Pb的吸附等温线用Langmuir和Freundlich方程拟合的相关性达到显著水平(P<0.05)。土壤对Pb的吸附强度(1/n)表现为稻田(0.711 7)>杉木林(0.695 3)>马尾松林(0.647 9)>竹林(0.533 4)>茶园(0.462 5),对Cu的吸附强度(1/n)表现为稻田(1.061 7)>马尾松林(0.839 6)>杉木林(0.537)>竹林(0.517 7)>茶园(0.421 7)。(3)在实验最大吸附量条件下,马尾松、杉木、竹林、茶园、稻田土壤Pb的解吸率分别为4.85%、2.72%、6.07%、5.47%、1.45%,Cu的解吸率分别为27.31%、25.95%、35.09%、52.82%、14.89%,Cu的解吸率远大于Pb的。(4)当Pb^(2+)、Cu^2共存时,Pb的竞争能力大于Cu的,不同土壤Pb和Cu的竞争作用表现为稻田﹥杉木林﹥马尾松林﹥竹林﹥茶园。茶园土壤Cu的解吸率较大,外源Cu易被茶树吸收,影响岩茶品质;且研究区内降雨量大且集中,Cu^(2+)随径流向区域内水体流失的风险较大。Five typical land use soils,collected from the acid red soil zone of South China,were analyzed to explore Pb and Cu adsorption-desorption characteristics of the soils. The research results show that:(1)In terms of Pb or Cu adsorption capacity with initial maximum concentrations of Pb or Cu added( 100 mg·L- 1solutions),a decreasing order was observed as paddy soil( 2 254. 35,1 254. 63 mg·kg^(-1)) > Chinese fir forest soil( 2 237. 33,732. 81 mg·kg^(-1)) > Pinus massoniana forest soil( 2 010. 66,581. 94 mg·kg^(-1)) > bamboo forest soil( 1 730. 47,470. 56 mg·kg^(-1)) > tea plantation soil( 1 574. 01,322. 69 mg·kg^(-1)). The order was same as the soil organic matter and CEC content.(2)Isothermal curves of Pb and Cu adsorption these five soils fit well to Langmuir and Freundlich equations( P < 0. 05). The adsorption intensity of Pb( 1 / n) ranked as follows: paddy soil( 0. 711 7) > Chinese fir forest soil( 0. 695 3) > Pinus massoniana forest soil( 0. 647 9) > bamboo forest soil( 0. 533 4) > tea plantation soil( 0. 462 5. The adsorption intensity of Cu( 1 /n) ranked as follows: paddy soil( 1. 061 7) > Pinus massoniana forest soil( 0. 839 6) > Chinese fir forest soil( 0. 537) > bamboo forest soil( 0. 517 7) > tea plantation soil( 0. 421 7).(3)The desorptive rates of Pb2 +was 4. 85%( Pinus massoniana forest soil),2. 72%( Pinus massoniana forest soil),6. 07%( bamboo forest soil),5. 47%( tea plantation soil),1. 45%( paddy soil). The desorptive rates of Cu^(2+)was27. 31%( Pinus massoniana forest soil),25. 95%( Pinus massoniana forest soil),35. 09%( bamboo forest soil),52. 82%( tea plantation soil),14. 89%( s paddy soil). The desorptive rates of Cu^(2+)was much higher than that of Pb^(2+).(4)The selective sequence of five soils to Pb and Cu adsorption was Pb > Cu in competitive adsorption. The competitive adsorption of Pb and Cu was observed as paddy soil > Chinese fir forest soil > Pinus massoniana forest soil > bamboo forest soil > tea plantation soil. The desorptive rates of Cu^(2+)in tea plantation soil was relative

关 键 词：吸附 解吸 铜 铅 土地利用 酸性红壤 

分 类 号：X131.3[环境科学与工程—环境科学] S152.4[农业科学—土壤学]