锡林河流域草地管理方式对植被和土壤及其风蚀的影响

发布时间：2018-05-26 12:32

本文选题：草地 + 管理方式　；参考：《内蒙古农业大学》2015年硕士论文

【摘要】：锡林河流域是我国北方重要的生态保护屏障,但随着自然气候变化和经济内驱力的影响,水土流失和荒漠化问题突显,草地生产能力下降,草畜矛盾日益尖锐。本论文以内蒙古锡林河流域典型草原上人为扰动草地、天然放牧草地、围封草地为材料,探究三种管理方式对草地植被、土壤及其风蚀的影响,以期揭示不同草地管理方式下植被、土壤及土壤风蚀的特点,为草地管理方式提供理论依据及科学指导,实现生态效益与经济效益平衡。试验得出以下结论：(1)在草地植被方面,人为扰动使得草地内植被高度、盖度、物种种数、植被多样性等指标下降,植被的生活型单一,一年生草本占据了优势地位。天然放牧使得草地内植被群落的物种多样、均匀度、优势度、丰富度下降,植物的物种种类共10种,分属于菊科、藜科、禾本科、鸢尾科,其中藜科的植物最多。围封措施增加了草地的物种数,群落的多样性、丰富度、均匀度以及优势度上升,并且多年生草本的优势度显著增加,群落以羊草、冰草、糙隐子草、冷蒿、克氏针茅为优势物种。随着围封年限的增加,植被盖度、高度、群落生态优势度增加,而物种种数、多样性指数、丰富度指数以及均匀度指数下降,草地群落成为了具有单优和寡优势种的群落。(2)在草地土壤方面,人为扰动使得草地表层土壤中粒径较大的颗粒含量增加,粒径较小的颗粒含量、0-15cm层土壤含水量、有机质含量以及紧实度降低。天然放牧使得0～15cm层土壤粒径0.250mm的颗粒百分含量是31%,细沙百分含量为32%,极细沙百分含量为21%；0～15cm层土壤有机质含量为13.11g,/kg。采取围封措施后土壤各项指标均优于天然放牧草地,具体表现为表层土壤中粒径较大的颗粒百分含量小,较小粒径的颗粒百分含量大,且随着围封年限的增加土壤中细粒物质百分含量增加。(3)在草地土壤风蚀方面,人为扰动使得地表粗糙度降低,采取围封措施后地表粗糙度增加,且围封12年草地地表粗糙度最大；同一风蚀过程中近地表0～50cm范围内人为扰动草地、天然放牧草地、围封3年草地以及围封12年草地的输沙量呈降低趋势,且以围封12年草地的风蚀程度最小。
[Abstract]:Xilin River Basin is an important ecological protection barrier in the north of China, but with the influence of natural climate change and economic driving force, the problems of soil and water loss and desertification are highlighted, the production capacity of grassland decreases, and the contradiction between grass and livestock becomes more and more acute. In this paper, the effects of three management methods on grassland vegetation, soil and wind erosion were studied by using artificial disturbance grassland, natural grazing grassland and enclosed grassland in Xilin River Basin, Inner Mongolia. In order to reveal the characteristics of vegetation, soil and soil wind erosion under different grassland management methods, to provide theoretical basis and scientific guidance for grassland management, and to achieve the balance between ecological and economic benefits. The following conclusions are drawn as follows: (1) in the aspect of grassland vegetation, artificial disturbance makes the vegetation height, coverage, species number and vegetation diversity decrease, the vegetation life type is single, and annual herbaceous plants occupy the dominant position. Natural grazing resulted in diversity, evenness, dominance and richness of vegetation community in grassland. There were 10 species of plants, belonging to Compositae, Chenopodiaceae, Gramineae, Iridaceae, among which Chenopodiaceae was the most. The number of species, the diversity, richness, evenness and dominance of the community were increased, and the dominance of perennial herbaceous was significantly increased. The community was composed of Leymus chinensis, Icegrass, Herba Sagittifolia, Artemisia frigida, and Artemisia frigida. Stipa Kirschsoni is the dominant species. With the increase of envelop life, vegetation coverage, height, ecological dominance of community increased, but species number, diversity index, richness index and evenness index decreased. Grassland community became the community with single dominant species and oligopoly species. (2) in grassland soil, artificial disturbance increased the content of larger particles in the surface layer of grassland, and the soil moisture content in the layer of 0-15 cm layer with smaller particle size. Organic matter content and compactness decreased. Natural grazing resulted in the content of soil particle fraction of 0.250mm in 0~15cm layer is 31%, the content of fine sand is 32%, and the content of soil organic matter is 13.11 g / kg in the layer of 21 ~ 0 ~ 15 cm layer of extremely fine sand. The indexes of soil were better than those of natural grazing grassland after the enclosed measures were adopted, which showed that the percentage content of the larger particles in the surface soil was smaller than that of the smaller ones, and the content of the smaller particles in the surface soil was higher than that in the natural grazing grassland. And with the increase of encapsulation years, the percentage of fine particles in soil increased. 3) in the aspect of grassland soil wind erosion, the surface roughness was decreased by artificial disturbance, and the surface roughness increased after the adoption of enclosure measures. The surface roughness of the enclosed grassland for 12 years was the largest, and the sediment transport rate of the artificial disturbance grassland, the natural grazing grassland, the enclosed grassland for 3 years and the enclosed grassland for 12 years showed a decreasing trend during the same wind erosion process in the range of 0~50cm near the surface. The degree of wind erosion was the lowest in enclosed grassland for 12 years.
【学位授予单位】：内蒙古农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S812

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