Mitigation of rice cadmium (Cd) accumulation by joint application of organic amendments and selenium (Se) in high-Cd-contaminated soils
Mitigation of rice cadmium (Cd) accumulation by joint application of organic amendments and selenium (Se) in high-Cd-contaminated soils
复制标题
在高镉污染土壤中联合施用有机改良剂和硒 (Se) 减少水稻镉 (Cd) 积累
DOI：
10.1016/j.chemosphere.2019.125106
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发表时间：
2020-02-01
期刊：
影响因子：
8.8
通讯作者：
Wei, Shiqiang
中科院分区：
文献类型：
--
作者：
Liu, Na;Jiang, Zhenmao;Wei, Shiqiang
采用盆栽试验研究了高镉污染土壤上施用有机添加剂（蚯蚓粪和生物炭）和硒（Se）对高镉积累水稻品种玉珍香（YZX）和低镉积累水稻品种长两优772（CLY）镉生物累积的影响。结果表明，镉敏感性和耐受性与品种有关，CLY籽粒镉含量符合中国国家食品安全标准（0.2 mg kg（-1）），而YZX籽粒镉含量是CLY的1.4-5.8倍。施用改良剂后，YZX和CLY的籽粒Cd含量分别降低了3.5%~ 36.9%和36.1%~ 74.4%。蚯蚓粪（VC）比生物炭（BC）更能有效地降低Cd的生物累积。硒与有机肥配施可显著提高籽粒硒含量，并使籽粒镉含量比单一有机肥降低5.8%~ 20.8%。这可能是由于镉在水稻组织中的迁移和分配发生了变化，并通过改变土壤性质抑制了土壤中镉的生物有效性。有机添加剂，特别是高剂量（5%），增加了土壤pH和有机质含量，降低了土壤Cd的生物有效性。连续提取分析表明，有机添加剂和硒促进了土壤Cd从生物有效态向固定态转化，从而降低了籽粒Cd含量。因此，有机添加剂与硒的配合施用以及低镉积累品种的选育，是一种既能满足人类硒需求，又能安全利用镉污染土壤的有效策略。(C)2019爱思唯尔有限公司版权所有。
A pot experiment was conducted to investigate the possible mediatory effect of organic amendments (vermicompost and biochar) and selenium (Se) on Cd bioaccumulation in both rice cultivars (high-Cd accumulation rice: Yuzhenxiang (YZX) and low-Cd accumulation rice: Changliangyou772 (CLY)) in high-Cd-contaminated soils. The results showed that Cd sensitivity and tolerance were cultivar-dependent, and grain Cd contents for CLY accorded with the Chinese national food safety standards (0.2 mg kg(-1)), whereas grain Cd levels for YZX were 1.4-5.8 times higher than those for CLY. Soil applications of amendments decreased grain Cd levels by 3.5%-36.9% for YZX and 36.1%-74.4% for CLY. Moreover, vermicompost (VC) was more effective in reducing Cd bioaccumulation than biochar (BC). A combination of Se and organic amendments could significantly increase grain Se contents and help further reduce grain Cd levels by 5.8%-20.8%, compared to the single organic amendments. This mitigation progress could be attributed to the changes of Cd translocation and distribution among rice tissues and the inhibition of Cd bioavailability in soil through the alteration in soil properties. Organic amendments, especially high dose (5%), increased soil pH and organic matter contents, and correspondingly decreased soil Cd bioavailability. A sequential extraction analysis suggested that organic amendments and Se facilitated the transformation of soil Cd from the bioavailable form to the immobilized Cd form, and thus decreased grain Cd levels. Hence, co-applications of organic amendments and Se in combination with low-Cd accumulation cultivar could be an effective strategy for both Se needs of humans and safe utilization of Cd polluted soil. (C) 2019 Elsevier Ltd. All rights reserved.