蕨类植物铝富集特征及影响因素研究

发布时间：2018-03-01 06:18

本文关键词： 铝土壤酸化里白狗脊天童　出处：《华东师范大学》2017年硕士论文　论文类型：学位论文

【摘要】：酸沉降引起的土壤酸化对生态环境和生物群落会带来一系列的影响,导致土壤中铝离子的活化并大量溶出,危害森林生态系统的健康。本文以浙江省宁波市天童国家森林公园为例,采集了天童森林公园不同海拔高度不同剖面的土壤样品以及狗脊、里白植株样品,探究了天童森林公园土壤酸化特征、蕨类植物狗脊和里白的铝、硅和铁富集特征,分析讨论了天童森林公园土壤发育程度及狗脊和里白的铝富集特征。主要研究结果如下:(1)土壤酸化特征:研究区土壤酸化明显,pH值从上剖面向土层深度增加,水解性总酸度和交换性酸均呈现由上剖面到下剖面降低的趋向;土壤粘土矿物由伊利石,高岭石和绿泥石构成,伊利石占绝对优势及上下剖面伊利石化学指数0.4;土壤不同剖面铝铁硅系数小于硅铝系数和铝铁系数;土壤游离度低于活化度及铁水合系数1.5;依据土壤酸化特征相关指标的测定结果,得出研究区土壤风化发育程度较低,处于脱硅向富铝化发展的初级阶段。(2)土壤铝溶出特征:研究区0-20 cm剖面土壤活性铝的含量先后分布规律是酸溶铝氧化物、腐殖酸螯合态铝、有机结合态铝、交换态铝、无机吸附态铝、水溶态铝;20-50cm土层的分布规律是腐殖酸螯合态铝、酸溶铝氧化物、交换态铝、有机结合态铝、无机吸附态铝、水溶态铝。土壤剖面0-20cm有效态活性铝占可提取活性铝的12.79%～20.46%,20-50 cm 土层有效态活性铝占可提取活性铝的9.39%～13.46%;通过与不同土壤类型植茶区进行横、纵向比较分析,得出该地有效态活性铝含量及其占可提取活性铝比例与之相当或较高。(3)蕨类植物铝富集特征:狗脊的根部铝含量最高且根部富集系数较高,植株的转移系数偏低(1),得出狗脊的铝累积特点是只有根中累积一定量的铝,但是植株地上部不累积;里白叶片中铝含量平均值为7.444 g/kg,地上部富集系数较高,转移系数为3.350(1),得出里白的铝累积特点是不仅根部能吸收高浓度的铝,植株地上部也能吸收高浓度的铝,属于铝累积植物。(4)蕨类植物铁、硅富集特征:蕨类植物狗脊和里白根部铁含量最高,地上部硅含量高于根部。狗脊的根部铁、硅含量与铝含量之间存在显著正相关(p0.05),表明狗脊植株对铝的吸收加强了对铁的吸收,且不影响植株吸收营养元素硅,根部具有富铁和富硅机制。里白根部铝含量与铁、硅含量之间达到极显著水平(p0.01),表明里白根部对铝吸收的同时不排斥对营养元素铁、硅的吸收,根部具有富铁机制,同时硅的吸收对铝在植株体内的迁移转化影响不大。
[Abstract]:The acidification of soil caused by acid deposition has a series of effects on the ecological environment and biota, which leads to the activation and dissolution of aluminum ions in soil. Taking Tiantong National Forest Park of Ningbo City, Zhejiang Province as an example, soil samples from different altitude profiles and samples of dog ridges and Lilai plants were collected from Tiantong Forest Park, Zhejiang Province. The characteristics of soil acidification in Tiantong Forest Park, the characteristics of aluminum, silicon and iron enrichment in the ferns' dog ridges and libai were investigated. The characteristics of soil acidification in Tiantong Forest Park were analyzed and discussed. The main results were as follows: the pH value of soil acidification increased from the upper profile to the depth of soil layer in the study area. The total hydrolytic acidity and exchangeable acid tended to decrease from the upper profile to the lower profile, and the clay minerals in the soil were composed of Illite, kaolinite and chlorite. Illite occupies the absolute dominance and the Illite chemical index is 0.4 in the upper and lower sections, and the Al-Fe-Si coefficient of soil in different profiles is lower than that of Si-Al and Al-Fe; The degree of soil dissociation is lower than that of activation and the coefficient of iron hydration is 1.5. According to the measurement results of soil acidification characteristics, it is concluded that the degree of soil weathering and development in the study area is lower than that in the study area. In the primary stage of desilication to aluminization, the characteristics of aluminum dissolution in soil: the distribution of active aluminum in soil in 0-20 cm profile is acid soluble aluminum oxide, humic acid chelate aluminum, organic bound aluminum and exchangeable aluminum. The distribution of inorganic adsorbed aluminum and water-soluble aluminum in the soil layer of 20-50 cm is that of humic acid chelate aluminum, acid-soluble aluminum oxide, exchangeable aluminum, organic bound aluminum, inorganic adsorbed aluminum. Water soluble aluminum. Available active aluminum in 0-20cm soil profile accounted for 12.79% of extractable active aluminum in 20.46 cm soil layer and 9.39% 13.46% of extractable active aluminum in 20-50 cm soil layer. The available active aluminum content and its proportion in extractable active aluminum were obtained. The characteristics of aluminum enrichment in pteridophytes were as follows: the highest Al content in the root and the higher enrichment coefficient in the root of the canine ridge. The transfer coefficient of the plant was lower than that of the control. It was found that only a certain amount of aluminum was accumulated in the root of the dog ridge, but not in the shoot, and the average aluminum content in the leaves of Libai was 7.444 g / kg, and the enrichment coefficient of the aboveground part was higher. The transfer coefficient is 3.350 ~ 1 ~ (-1). The characteristic of aluminum accumulation in Libai is that not only the roots can absorb high concentration of aluminum, but also the aboveground part of plants can absorb high concentration of aluminum, which belongs to the aluminum accumulative plant. The characteristics of silicon enrichment: the iron content in the roots of pteridophyte dog ridges and libbeas was the highest, and the content of silicon in the aboveground part was higher than that in the roots. There was a significant positive correlation between Si content and Al content, which indicated that the absorption of Al by Doggesia plants enhanced the absorption of Fe, and had no effect on the absorption of nutrient element Si by the plant, and the roots had the mechanism of rich in Fe and rich in Si, and the content of Al in the root of Libai was related to iron, and the content of Al in the root of Libai increased the absorption of Fe. The content of Si reached a significant level (p 0.01), which indicated that the root of Libai did not exclude the absorption of iron and silicon at the same time, the absorption of Fe and Si in the root had the mechanism of iron enrichment, and the absorption of silicon had little effect on the migration and transformation of aluminum in the plant.
【学位授予单位】：华东师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X173

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