施用海泡石对铅、镉在土壤-水稻系统中迁移与再分配的影响

发布时间：2018-04-04 07:39

  本文选题：水稻　切入点：海泡石　出处：《环境科学》2017年07期

【摘要】：以浙江省绍兴市某铅(Pb)、镉(Cd)复合重污染地区土壤(全Pb含量为2 028.22 mg·kg~(-1),全Cd含量为2.36 mg·kg~(-1))及具有低Pb、Cd积累特性的浙江省典型晚粳稻品种嘉33为对象,通过土培盆栽试验,研究了海泡石的施用对铅、镉复合污染土壤中有效态Pb、Cd的含量以及水稻植株对Pb、Cd的吸收和分配关系的影响.结果表明:供试土壤中有效态Pb、Cd的含量与添加的海泡石量呈显著负相关,其相关系数分别为-0.940、-0.952,均达到显著水平(P0.01).随着海泡石添加量的增加,水稻根、茎、叶和精米中Pb、Cd的含量有不同程度地降低,水稻根、茎、叶及精米对Pb、Cd的富集系数显著下降,同时茎对根系吸收的Pb、Cd以及精米对茎中Pb、Cd的转运系数也显著下降.当海泡石的添加量为9.00 g·kg~(-1)土时,嘉33精米中的Pb、Cd含量分别为(0.14±0.02)mg·kg~(-1)、(0.03±0.01)mg·kg~(-1),均低于国家的限量指标(GB 2762-2012);相比于对照组而言,水稻根、茎、叶及精米对Pb的富集系数分别下降了8.83%、29.96%、49.20%、79.41%,对Cd的富集系数分别下降了23.08%、63.22%、44.00%、82.35%;另外,茎对根吸收的Pb、Cd的转运系数分别下降了23.18%、52.19%,精米对茎转运的Pb、Cd的转运系数分别下降了70.83%、52.00%,意味着在铅、镉复合重污染土壤上,海泡石同时对重金属Pb、Cd在土壤-水稻系统的迁移与再分配具有较好的阻控作用,合理施用海泡石与低重金属积累品种相结合可以实现污染浓度相对较高的重金属Pb、Cd复合污染土壤的农业安全利用.
[Abstract]:The effects of sepiolite application on the contents of available Pb and CD in Pb and CD contaminated soil and the relationship between uptake and distribution of Pb + CD by rice plants were studied.The results showed that there was a significant negative correlation between the content of available Pb ~ (2 +) CD and the amount of sepiolite added in the tested soil, and the correlation coefficients were -0.940 ~ 0.952, respectively, and reached the significant level of P0.01C.With the increase of sepiolite addition, the content of Pb ~ (2 +) CD in rice roots, stems, leaves and milled rice decreased to some extent, and the enrichment coefficient of Pb ~ (2 +) CD in rice roots, stems, leaves and milled rice decreased significantly.At the same time, the transport coefficient of Pb ~ (2 +) CD from stem to root and from milled rice to stem was also decreased significantly.褰撴捣娉＄煶鐨勬坊鍔犻噺涓，

本文编号：1708998