不同改良剂对石灰性土壤镉污染的修复效应

发布时间：2017-12-26 19:26

本文关键词：不同改良剂对石灰性土壤镉污染的修复效应　出处：《石河子大学》2015年硕士论文　论文类型：学位论文

更多相关文章： 有机肥 油菜 小白菜 改良剂 镉含量

【摘要】：【研究目的】我国农业土壤重金属污染十分严重,在所有重金属中,镉是毒性最高的元素之一。近年来,修复镉污染土壤已成为我国农业可持续发展亟待解决的问题。改良剂一般通过吸附、离子交换、表面沉淀、络合、氧化还原等机理作用于土壤中的重金属,其成本低廉、安全性高,是目前研究最多的一项经济、高效的治理技术。因此,研究改良剂对土壤中镉的转化、积累以及植物对镉吸收的影响,能够为农业生产中合理改良镉污染土壤提供参考。【研究方法】本研究采用盆栽试验,以小白菜和油菜为试验材料,研究在我国西北地区石灰性土壤中不同改良剂对土壤中镉的含量、形态转化以及小白菜和油菜对镉的吸收与积累的影响。本试验分为两部分进行:第一部分为预试验,研究有机肥对小白菜、油菜镉吸收量的影响。第二部分为试验部分,采用盆栽试验,分别在正常土壤(A)、低镉含量土壤(B)、高镉含量土壤(C)3种土壤上种植小白菜和油菜,以鸡粪、腐殖酸、生物碳和海泡石4种改良剂分别以不同含量施入各土壤,研究4种改良剂及其用量对小白菜和油菜生物量、镉吸收量及土壤镉含量与形态转化的影响。【主要结果】预试验主要结果:(1)施用较高含量的有机肥均可显著提高小白菜和油菜的生物量。土壤中一定的镉含量可以促进小白菜地上部的生物量。(2)添加有机肥对污染土壤中小白菜和油菜镉的吸收量有显著影响,且有机肥对油菜的作用大于小白菜。小白菜在各土壤上对镉均有超富集作用。试验主要研究结果:(1)在正常土壤上,改良剂对油菜和小白菜地上部分生物量的影响基本一致,施用高含量的鸡粪处理均显著增加了小白菜和油菜的生物量。在土壤镉含量为1.5 mg·kg-1时,鸡粪均显著增加了小白菜与油菜地上部生物量。在土壤镉含量为3.0mg·kg-1时,鸡粪对油菜生物量有显著的作用,高施用量的鸡粪也提高了小白菜的生物量,说明改良剂的不同施用量对小白菜和油菜均有不同的影响。(2)在正常土壤上,改良剂对油菜和小白菜地上部镉含量影响均不显著。当土壤镉含量为1.5 mg·kg-1时,4种改良剂对油菜地上部的镉含量均有降低。在土壤镉含量为3.0 mg·kg-1时,不同改良剂对油菜和小白菜地上部镉含量影响各异,且不同施用量对其影响也不同。(3)在正常土壤中,腐殖酸、生物碳和鸡粪均显著降低了种植小白菜和油菜土壤中的镉含量。当土壤中镉含量1.5 mg·kg-1时,4种改良剂对均显著降低土壤中的镉含量。当土壤镉含量为3.0 mg·kg-1时,4种改良剂较对照土壤均显著降低了种植小白菜土壤中的镉含量,且腐殖酸处理的降低效果最佳。(4)有机改良剂腐殖酸、鸡粪和生物碳不同程度的促进了土壤中的镉由不可利用态向潜在生物可利用态和可利用态的转化,而海泡石则钝化了有效态镉含量,不利于植物根系对镉离子的吸收;生物碳增加了土壤中碳酸盐态镉的存在比例;鸡粪作为一种特殊的有机改良剂施入土壤后,土壤镉主要以交换态、碳酸盐结合态和铁锰氧化态形式存在,其他形态镉含量均很少;改良剂对土壤中镉形态的影响在修复土壤方面起着至关重要的作用。【结论】有机肥不仅可以提高作物生长,还可以促进小白菜和油菜对镉的吸收,小白菜对镉的超积累能力优于油菜。鸡粪可以显著增加小白菜与油菜的生物量,4种改良剂的施用量的不同对小白菜与油菜地上部镉含量也有显著差异。鸡粪、生物碳和腐殖酸对土壤镉有活化的作用,海泡石抑制了土壤中镉的有效化。
[Abstract]:[Objective] the pollution of heavy metals in agricultural soils of China is very serious. Among all the heavy metals, cadmium is one of the most toxic elements. In recent years, the remediation of cadmium contaminated soil has become an urgent problem to be solved in the sustainable development of agriculture in China. Amelioration agents generally act on heavy metals in soil by adsorption, ion exchange, surface precipitation, complexation, redox and other mechanisms. Their cost is low and safety is high. It is currently an economical and efficient treatment technology. Therefore, studying the effects of modifiers on the transformation and accumulation of cadmium in soil and the effect of plants on cadmium absorption can provide references for improving cadmium contaminated soil in agricultural production. [method] the pot experiment was conducted to study the effects of different amendments on calcareous soil cadmium content, morphological transformation and absorption and accumulation of cadmium in Chinese cabbage and rape. The experiment was divided into two parts: the first part was the pretest to study the effect of organic fertilizer on the absorption of cadmium in Chinese cabbage and rapeseed. The second part is the experiment part, pot experiments were conducted respectively in normal soil (A), low cadmium content of soil (B) and high cadmium content of soil (C) of 3 soil types in Chinese cabbage and rape, chicken manure, humic acid, bio carbon and sepiolite 4 kinds of modifiers with different content of each application study on the influence of 4 kinds of soil improver and its dosage on Chinese cabbage and rape biomass and Cd uptake and accumulation of cadmium in soil and transformation. The main results were as follows: (1) the high content of organic fertilizer could significantly increase the biomass of cabbage and rapeseed. A certain amount of cadmium in the soil can promote the biomass of the upper part of Chinese cabbage. (2) adding organic fertilizer had a significant effect on the absorption of cadmium in Chinese cabbage and rapeseed in contaminated soil, and the effect of organic manure on rape was greater than that of Chinese cabbage. Chinese cabbage has hyperconcentration on Cadmium in every soil. The main results of the experiment were as follows: (1) on the normal soil, the effects of amendments on the aboveground biomass of rape and pakchoi were basically the same. The high biomass of chicken manure significantly increased the biomass of Chinese cabbage and Brassica napus. When the soil cadmium content was 1.5 mg. Kg-1, chicken manure significantly increased the biomass of Brassica napus and Brassica napus. When the soil cadmium content is 3.0mg. Kg-1, chicken manure has a significant effect on rape biomass. The chicken manure with higher application dose also increased the biomass of pakchoi, indicating that different application amount of modifier had different effects on Chinese cabbage and rape. (2) on the normal soil, the effect of the modifier on the content of Cd in the upper part of Brassica napus and pakchoi was not significant. When the soil cadmium content was 1.5 mg. Kg-1, the content of cadmium in the upper part of the rapeseed was reduced by the 4 modifiers. When soil cadmium content was 3 mg. Kg-1, different modifiers had different effects on the content of Cd in the upper part of Brassica napus and pakchoi, and the effects of different dosage on the CD content were different. (3) in the normal soil, humic acid, bio carbon and chicken manure significantly decreased the content of cadmium in the soil of Brassica napus and Brassica napus. When the content of cadmium in the soil was 1.5 mg. Kg-1, the 4 modifiers significantly decreased the content of cadmium in the soil. When the cadmium content of soil was 3 mg. Kg-1, the 4 kinds of amendments significantly reduced the cadmium content in the soil of cabbage, compared with the control soil, and the effect of humic acid treatment was the best. (4) organic modifier humic acid, chicken manure and biological carbon in different degree to promote the cadmium in the soil by not available to potential biological availability and availability of the transformation, and then the effective cadmium passivation of sepiolite content, is not conducive to the absorption of plant roots on cadmium ion; biological carbon increase the ratio of carbonate bound cadmium in soil; manure as an organic modifier for special application in soil, cadmium in soil mainly in the exchangeable, carbonate bound and Fe Mn oxidized form, other forms of cadmium content are few; effects of amendments on CD forms in soil plays an important role in the repair of soil. [Conclusion] organic fertilizer can not only improve the growth of crops, but also promote the absorption of cadmium in Chinese cabbage and rapeseed, and the super accumulation of cadmium in Chinese cabbage is better than that of rape. Chicken manure could significantly increase the biomass of Brassica napus and Brassica napus, and the difference in the application of the 4 modifiers had significant difference on the content of Cd in the upper part of Brassica napus and Brassica napus. The effect of chicken manure, bio carbon and humic acid on Cadmium in soil was activated, and sepiolite inhibited the availability of cadmium in soil.
【学位授予单位】：石河子大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X53

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