Darmody R G, Marlin J C, Talbott J, Green R A, Brewer E F, Stohr C
Dep. of Natural Resources and Environ. Sciences, Univ. of Illinois, 1102 S. Goodwin Ave., Urbana, IL 61801, USA.
J Environ Qual. 2004 Mar-Apr;33(2):458-64. doi: 10.2134/jeq2004.4580.
Sedimentation of the Illinois River in central Illinois has greatly diminished the utility and ecological value of the Peoria Lakes reach of the river. Consequently, a large dredging project has been proposed to improve its wildlife habitat and recreation potential, but disposal of the dredged sediment presents a challenge. Land placement is an attractive option. Previous work in Illinois has demonstrated that sediments are potentially capable of supporting agronomic crops due to their high natural fertility and water holding capacity. However, Illinois River sediments have elevated levels of heavy metals, which may be important if they are used as garden or agricultural soil. A greenhouse experiment was conducted to determine if these sediments could serve as a plant growth medium. A secondary objective was to determine if plants grown on sediments accumulated significant heavy metal concentrations. Our results indicated that lettuce (Lactuca sativa L.), barley (Hordeum vulgare L.), radish (Raphanus sativus L.), tomato (Lycopersicon lycopersicum L.), and snap bean (Phaseolus vulagaris L. var. humillis) grown in sediment and a reference topsoil did not show significant or consistent differences in germination or yields. In addition, there was not a consistent statistically significant difference in metal content among tomatoes grown in sediments, topsoil, or grown locally in gardens. In the other plants grown on sediments, while Cd and Cu in all cases and As in lettuce and snap bean were elevated, levels were below those considered excessive. Results indicate that properly managed, these relatively uncontaminated calcareous sediments can make productive soils and that metal uptake of plants grown in these sediments is generally not a concern.
伊利诺伊州中部伊利诺伊河的泥沙淤积极大地降低了该河皮奥里亚湖段的利用价值和生态价值。因此，有人提议开展一项大型疏浚工程，以改善其野生动物栖息地和休闲潜力，但疏浚泥沙的处置带来了挑战。陆地填埋是一个有吸引力的选择。伊利诺伊州此前的研究表明，由于泥沙天然肥力高且持水能力强，它们有潜力用于种植农作物。然而，伊利诺伊河泥沙中的重金属含量较高，如果将其用作花园或农业土壤，这可能是个重要问题。为此进行了一项温室试验，以确定这些泥沙能否用作植物生长介质。第二个目标是确定在泥沙上生长的植物是否积累了大量重金属。我们的结果表明，在泥沙和参照表土中种植的生菜（Lactuca sativa L.）、大麦（Hordeum vulgare L.）、萝卜（Raphanus sativus L.）、番茄（Lycopersicon lycopersicum L.）和菜豆（Phaseolus vulagaris L. var. humillis）在发芽率或产量上没有显著或一致的差异。此外，在泥沙、表土或当地花园中种植的番茄之间，金属含量在统计学上也没有一致的显著差异。在泥沙上生长的其他植物中，虽然所有情况下镉和铜以及生菜和菜豆中的砷含量都有所升高，但均低于被认为过高的水平。结果表明，经过适当管理，这些相对未受污染的钙质泥沙可以形成肥沃的土壤，并且在这些泥沙中生长的植物对金属的吸收通常无需担忧。
