College of Resource and Environment, Hunan Agricultural University, Changsha 410128, PR China.
College of Resource and Environment, Hunan Agricultural University, Changsha 410128, PR China.
Chemosphere. 2019 Dec;236:124379. doi: 10.1016/j.chemosphere.2019.124379. Epub 2019 Jul 16.
In order to study the role of mulberry (Moms alba L) as an economic crop for remediation of cadmium (Cd) contaminated soil, the transport of Cd from mulberry to silkworm were investigated. Three varieties of mulberry (Yuesang-11, Nongsang-14, and Qiangsang-1) with three planting densities were cultivated in two heavy metal-contaminated fields named Dongkou in Shaoyang city and Linxiang in Yueyang city in Hunan province respectively. The both field soils were contaminated by heavy metals, especially by Cd. The potential risks of heavy metals in Linxiang's soil were higher than those in Dongkou's because of higher concentrations of Cd. Since the promotion of Cd concentrations in aerial parts (stem, branch and leaf) resulted from the increase of planting density, the method of high planting density is beneficial to improve the efficiency of the remediation of Cd contaminated soil. The percentages of average Cd contents of mulberry in Dongkou accounted for 44%, 20%, 18% and 16% in roots, stems, branches and leaves respectively, while the Cd contents were 38%, 27%, 19% and 16% distributed in roots, stems, branches and leaves respectively. Mulberry leaves from contaminated soils was applied in food source of silkworms in this study. Although there is Cd uptake occurred in silkworm growth and its products (cocoons and chrysalis), Cd contents in cocoons are lower than the national standard (100 μg*kg-1) for textile industry of China. Therefore, mulberry can be regarded as an economical crop to control soil contamination with Cd.
为了研究桑树（Moms alba L）作为一种经济作物修复镉（Cd）污染土壤的作用，研究了 Cd 从桑树向家蚕的迁移。在湖南省邵阳市洞口县和岳阳市临湘县两个重金属污染区，分别种植了三个桑树品种（粤桑 11 号、农桑 14 号和强桑 1 号），种植密度为三种。两块农田的土壤均受到重金属污染，特别是 Cd 污染。由于临湘土壤中的 Cd 浓度较高，其重金属潜在风险高于洞口土壤。由于种植密度增加导致地上部分（茎、枝和叶）中 Cd 浓度增加，高种植密度的方法有利于提高修复 Cd 污染土壤的效率。在洞口，桑树各部位（根、茎、枝和叶）中 Cd 含量的平均值分别占 44%、20%、18%和 16%，而 Cd 含量分别占 38%、27%、19%和 16%。受污染土壤中的桑叶在本研究中被用作家蚕的食物来源。尽管在蚕的生长及其产品（蚕茧和蛹）中存在 Cd 吸收，但蚕茧中的 Cd 含量低于中国纺织工业的国家标准（100μg*kg-1）。因此，桑树可以被视为一种经济作物，用于控制 Cd 污染的土壤。
