Assessing availability, phytotoxicity and bioaccumulation of lead to ryegrass and millet based on 0.1 mol/L Ca(NO_3)_2 extraction

作     者：SI Ji-tao TIAN Bao-guo WANG Hong-tao Nicholas Basta Jackie Schroder Mark Casillas 

作者机构：Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China School of Natural Resources The Ohio State University Columbus OH 43210 USA Department of Plant and Soil Sciences Oklahoma State University Stillwater Oklahoma 74078 USA 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2006年第18卷第5期

页      面：958-963页

核心收录：

学科分类：082803[工学-农业生物环境与能源工程] 08[工学] 0828[工学-农业工程] 09[农学] 0903[农学-农业资源与环境] 

基　　金：The Strategic Environment Research and Development Program(SERDP)  USA Project and the Alcoa Foundations Conservation andSustainability Fellowship Program (SDRAC) 

主　　题：heavy metals bioconcentration factor spike extraction lead (Pb) 

摘      要：This study was conducted to assess availability, phytotoxicity and bioaccumulation of lead （Pb） to ryegrass （Lolium perenne L.） and millet （Echinochloa crusgalli） based on the 0.1 mol/L Ca（NO3）2 extraction. Effect of soil properties on availability, phytotoxicity and bioaccumulation of Pb to the two plants was also evaluated. Five soils with pH values varying from 3.8 to 7.3, organic carbon （OC） contents from 0.7% to 2.4%, and clay contents from 11.6% to 35.6% were selected. Soils were spiked with Pb to achieve a range of concentrations： 250, 500, 1000, 3000 and 5000 mg/kg. Pb availability in the spiked soils was estimated by extracting soil with 0.1 mol/L Ca（NO3）2. The results indicate that plants yield decreased with decreasing soil pH and increased with increasing soil clay and OC content. Negative relationship between available Pb and the relative dry matter growth （RDMG） of the two plants were significantly related. Available Pb used to assess EC20 （20% effective concentration） and EC50 （50% effective concentration） of millet was 119 and 300 mg/kg, respectively. Available Pb used to assess EC20 and EC50 of ryegrass was 63 and 157 mg/kg, respectively. Bioaccumulation, expressed as bioconcentration factors of Pb, was inversely related to soil pH, soil OC and clay content. Strong relationships were found between available lead and uptake by the two plants （P was 0.92 and 0.95 respectively）. In general, 0.1 mol/L Ca（NO3）2 available Pb may be used to assess the availability, phytotoxicity and bioaccumulation of lead to the two plants tested.