黄土高原不同植被条件下土壤可溶性有机质的荧光特征

发布时间：2018-03-22 08:36

本文选题：植被　切入点：土壤可溶性有机质　出处：《西安建筑科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：土壤可溶性有机质的组成和结构是土壤质量的重要判别指标,具有重要的生态意义。研究黄土丘陵地区不同植被下土壤可溶性有机质的数量和荧光结构特征,可以为该地的植被修复及土壤质量评价提供科学依据。本文利用传统荧光和三维荧光技术,选取激发发射荧光光谱、同步荧光光谱得到的腐殖化指标对土壤可溶性有机物的来源和结构进行评估,通过三维荧光技术探究不同植被下土壤可溶性有机质之间组分的差异。主要结果如下:(1)黄土丘陵区土壤可溶性有机质大多来源于植物和微生物的混合作用;油松林地(Pinus tabulaeformia)的可溶性有机质结构较简单、腐殖化程度较低;而灌木林地(Vitex negundo var.heterophylla)的可溶性有机质结构较为复杂、腐殖化程度较高。(2)沙漠湖泊区盐碱地、沼泽化草甸10-50 cm土层可溶性有机质的腐殖化指数较高,而50-100 cm土壤的腐殖化指数较低;草地土壤芳香化程度较低;草原化沙地、沙地的可溶性有机质腐殖化程度在不同土壤深度差异很小。(3)风蚀水蚀区处于东南坡的小叶杨(Populus simonii Carr)、沙柳(Salix cheilophila)和沙蒿(Artemisia desertorum Spreng.Syst.Veg.)可溶性有机质的缩合程度较低;而同处于东南坡的柠条(Caragana Korshinskii Kom)、坡顶的长茅草(Stipa bungeana Trin.)和位于阳坡的苜蓿(Medicago)土壤可溶性有机质芳香性较高。(4)黄土丘陵沟壑区荒地的可溶性有机质的含量较高,人工植被条件下柠条(Caragana Korshinskii Kom)、苜蓿(Medicago)的可溶性有机质含量高于红梅杏(Armeniaca vulgaris Lam.)和山杏(Armeniaca sibirica(L.)Lam.),可溶性有机质含量在表层0-20 cm较高,富里酸类和胡敏酸类物质含量也在表层较高。(5)不同地区的煤矿土壤可溶性有机质的缩聚度不同。煤矿区上河煤矿可溶性有机质缩聚度高,而银河薛庙滩煤矿可溶性有机质腐殖化程度较低,中能煤矿、永乐煤矿可溶性有机质的腐殖化程度也处于较低的水平。研究结果表明不同土壤类型不同植被条件下的土壤可溶性有机质的组成和结构是存在差异的,同时说明荧光技术可用于揭示可溶性有机物的组成和缩合特性研究。
[Abstract]:The composition and structure of soil soluble organic matter is an important discriminant index of soil quality and has important ecological significance. The quantity and fluorescence structure characteristics of soil soluble organic matter under different vegetation in loess hilly region were studied. It can provide scientific basis for vegetation restoration and soil quality evaluation. In this paper, excitation emission fluorescence spectra are selected by using traditional fluorescence and three-dimensional fluorescence techniques. The source and structure of soluble organic matter in soil were evaluated by humification index obtained by synchronous fluorescence spectroscopy. The difference of soil soluble organic matter in different vegetation was studied by three dimensional fluorescence technique. The main results were as follows: 1) most of the soluble organic matter in loess hilly region originated from the mixed action of plant and microorganism. The structure of soluble organic matter of Pinus tabulaeformiais simple and the degree of humification is lower, while the structure of soluble organic matter of Vitex negundo var. heterophylla is more complex, and the degree of humification is higher. The humification index of soluble organic matter in 10 ~ 50 cm soil layer of marsh meadow was higher than that of 50 ~ 100 cm soil layer, while the humification index of 50 ~ 100 cm soil layer was lower; the aromatization degree of grassland soil was lower; The degree of humification of soluble organic matter in sandy land is very small in different soil depth. 3) the condensation degree of soluble organic matter of Populus simonii Carru (Salix cheilophila) and Artemisia desertorum desertorum Spreng.Syst.Veg. in the wind-eroded water erosion area on the southeastern slope is lower; However, the content of soluble organic matter in the soil of Caragana Korshinskii Komna, Stipa bungeana Trin. on the top of the slope and Medicago in the sunny slope was higher than that in the loess hilly and gully region, and the content of soluble organic matter was higher in the wasteland of the loess hilly and gully region. Under artificial vegetation, the soluble organic matter content of Caragana Korshinskii Komao (Medicago) was higher than that of armeniaca vulgaris Lam. and armeniaca sibiricae L.Lam.The content of soluble organic matter was higher in surface layer 0-20 cm. The condensate degree of soluble organic matter in coal mine soil is different in different areas, and the condensation degree of soluble organic matter is high in Shanghe coal mine. However, the humification degree of soluble organic matter in Yinxue Miaotan coal mine is low, and the middle energy coal mine, The humification degree of soluble organic matter in Yongle Coal Mine is also at a low level. The results show that the composition and structure of soluble organic matter in different soil types and vegetation conditions are different. At the same time, fluorescence technique can be used to reveal the composition and condensation characteristics of soluble organic compounds.
【学位授予单位】：西安建筑科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S153.6

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