Increased fluctuation of sulfur alleviates cadmium toxicity and exacerbates the expansion of Spartina alterniflora in coastal wetlands
Increased fluctuation of sulfur alleviates cadmium toxicity and exacerbates the expansion of Spartina alterniflora in coastal wetlands
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硫波动的增加减轻了镉的毒性并加剧了沿海湿地互花米草的扩张
DOI：
10.1016/j.envpol.2021.118399
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发表时间：
2022
影响因子：
8.9
通讯作者：
Daolin Du
中科院分区：
文献类型：
--
作者：
Yueming Wu;Zhanrui Leng;Jian Li;Hui Jia;Chongling Yan;Hualong Hong;Qiang Wang;Yanyan Lu;Daolin Du
证据表明互花米草（Spartinaalterniflora（S.互花米草（alterniflora）对沿海湿地的稳定构成潜在的严重风险，而沿海湿地是一个极易受到生物和非生物威胁的生态系统。但硫在介导细菌生长和膨胀中的作用和机制尚不清楚。对互花米草的了解很少，特别是当沉积物被镉（Cd）污染时。通过为期6个月的温室试验，研究了硫对水稻耐镉性和生长的调节作用。互花处理包括三个硫水平（以Na 2SO 4; 0、500、1000 mg kg− 1干重（DW），以S 0、S500和S1000）和四个镉水平（以CdCl 2; 0、1、2、4 mg kg− 1 DW，以Cd 0、Cd 1、Cd 2和Cd 4）的析因组合。结果表明，虽然外源S显著增加了根中Cd的积累量（71.22 ± 6.43 mg kg−1DW），但由于铁膜中Fe含量降低（4.02 ± 1.18 mg g−1DW），植物组织中的生物量减少和氧化胁迫得到了显著缓解。S的加入显著上调了与Cd耐性相关的化合物的浓度，包括脯氨酸和谷胱甘肽。因此，限制了Cd的转运，而不影响植物的生长。本研究表明，外源硫的供应可以促进S.互花米草对Cd的耐性增强。因此，在S.互花米草中S的释放和沉积所引起的S库波动增加可能进一步加剧S.在Cd污染的滨海湿地中，
Evidence suggests that the invasion ofSpartinaalterniflora(S. alterniflora) poses potentially serious risks to the stability of coastal wetlands, an ecosystem that is extremely vulnerable to both biological and non-biological threats. However, the effects and mechanisms of sulfur (S) in mediating the growth and expansion ofS. alternifloraare poorly understood, particularly when sediments are contaminated with cadmium (Cd). A 6-month greenhouse study was conducted to evaluate the mediating effect of S on Cd tolerance and growth ofS. alterniflora. Treatments consisted of a factorial combination of three S rates (applied as Na2SO4; 0, 500, 1000 mg kg−1dry weight (DW), as S0, S500, and S1000) and four Cd rates (applied as CdCl2; 0, 1, 2, 4 mg kg−1DW, as Cd0, Cd1, Cd2, and Cd4). Results showed that although the exogenous S supply obviously increased Cd accumulation in roots (up to 71.22 ± 6.43 mg kg−1DW) due to the decrease of Fe concentration in iron plaque (down to 4.02 ± 1.18 mg g−1DW), biomass reduction and oxidative stress in plant tissues were significantly alleviated. The addition of S significantly up-regulated the concentration of compounds related to Cd tolerance, including proline and glutathione. Therefore, the translocation of Cd was restricted, and plant growth was not impacted. The present study demonstrated that the exogenous sulfur supply could promote the growth ofS. alternifloraand enhance its tolerance to Cd. Therefore, under the effects ofS. alterniflora, the increased fluctuations of S pool caused by the release and deposition of S might further exacerbateS. alternifloraexpansion in Cd contaminated coastal wetlands.