CAJ | 학술논문

以玉米和大豆为试验材料，研究了单种、套种对土壤重金属含量及迁移转化规律的影响。试验结果表明，试验区土壤中Pb、Cd和Zn含量均超过土壤环境质量二级标准（GB 1518—2008）。套种时，非根系和根系土壤中Pb、Zn、Cu、Cd、Fe和Mn含量呈下降趋势，但与单种无显著性差异，种植模式对土壤重金属形态影响显著不同，且根系土壤与非根系土壤差异显著。根系土壤和非根系土壤中Zn、Cu、Fe和Mn以残渣态为主，占50%以上，而Pb以铁锰结合态为主，非根系土壤中铁锰结合态Pb的比例约为40%，而根系土壤约为50%。根系土壤中可交换态和碳酸盐结合态Cd的比例分别占土壤中Cd总量的14.01%~15.82%和9.56%~9.90%，与根系土壤相比，非根系土壤中可交换态Cd和碳酸盐结合态Cd的比例分别高0.63~0.85倍和1.38~1.48倍。研究还发现，大豆和玉米对Pb、Zn、Cu、Cd、Fe和Mn吸收富集能力显著不同，且种植模式对植物吸收富集重金属能力也有显著性影响。在试验区土壤中种植大豆和玉米，重金属在土壤-植物系统中的迁移率都比较高，从而使作物可食部分重金属含量较高，大豆中Pb和Cd含量分别超标48.0~53.5倍和24.8~30.8倍，玉米中Pb和Cd含量分别超标47.2~51.8倍和9.7~15.8。所有试验结果显示，在试验区种植粮食作物存在较大的健康风险，且水改旱不能实现试验区土壤重金属污染治理的目的。
이옥미화대두위시험재료，연구료단충、투충대토양중금속함량급천이전화규률적영향。시험결과표명，시험구토양중Pb、Cd화Zn함량균초과토양배경질량이급표준（GB 1518—2008）。투충시，비근계화근계토양중Pb、Zn、Cu、Cd、Fe화Mn함량정하강추세，단여단충무현저성차이，충식모식대토양중금속형태영향현저불동，차근계토양여비근계토양차이현저。근계토양화비근계토양중Zn、Cu、Fe화Mn이잔사태위주，점50%이상，이Pb이철맹결합태위주，비근계토양중철맹결합태Pb적비례약위40%，이근계토양약위50%。근계토양중가교환태화탄산염결합태Cd적비례분별점토양중Cd총량적14.01%~15.82%화9.56%~9.90%，여근계토양상비，비근계토양중가교환태Cd화탄산염결합태Cd적비례분별고0.63~0.85배화1.38~1.48배。연구환발현，대두화옥미대Pb、Zn、Cu、Cd、Fe화Mn흡수부집능력현저불동，차충식모식대식물흡수부집중금속능력야유현저성영향。재시험구토양중충식대두화옥미，중금속재토양-식물계통중적천이솔도비교고，종이사작물가식부분중금속함량교고，대두중Pb화Cd함량분별초표48.0~53.5배화24.8~30.8배，옥미중Pb화Cd함량분별초표47.2~51.8배화9.7~15.8。소유시험결과현시，재시험구충식양식작물존재교대적건강풍험，차수개한불능실현시험구토양중금속오염치리적목적。
Plant species have different impacts on forms and transformation of heavy metals in soil. Here an experiment was performed to in-vestigate the effects of single and inter-planting of soybean and maize on content, forms and migration of soil heavy metals in dryland in Southern China. Results showed that the content of Pb, Cd and Zn exceeded the second grade levels of the National Soil Environmental Quality Standard(GB 1518—2008). Compared to the soil with single planting, Pb, Zn, Cu, Cd, Fe and Mn concentrations under the inter-planting tended to decrease in both rhizospheric and non-rhizospheric soils. However, plating patterns had significant effects on forms of soil heavy metals. The forms of soil heavy metals were significantly different between rhizospheric and non-rhizospheric soils. Residual form was the main fraction of Zn, Cu, Fe and Mn in both rhizospheric and non-rhizospheric soils, accounting for more than fifty percent. The forms of Pb and Cd were significantly different from those of Zn, Cu, Fe and Mn. Oxide bound Pb was the major fraction in both rhizospheric and non-rhizospheric soils, constituting about forty percent in non-rhizospheric soil and about fifty percent in rhizospheric soil. Percentages of exchangeable and carbonate bound Cd were respectively 14.01%~15.82% and 9.56%~9.90% in rhizospheric soil, while 0.63~0.85 and 1.38~1.48 times more in non-rhizospheric soil. The content of Pb, Zn, Cu, Cd, Fe and Mn was significantly different between soybean and maize, and influenced by planting patterns. Lead and Cd in edible part of soybean were 37.95~43.45 and 50.5~52.6 times higher, while in maize 47.2~56.8 and 9.7~15.8 times more than the limits for pollution standard in food(GB 2762—2012), respectively. These results show that food crops planted in the tested field had high health risks and that changing from paddy field to dry land is not an option for remedia-tion of soil contaminated with heavy metals.