以防治侵蚀为目标的阳崖流域植被缓冲带技术
发布时间：2018-11-29 12:29
【摘要】：砒砂岩区由于砒砂岩自身的易蚀性以及干旱风大、降雨集中等恶劣的自然条件,加之人为因素的干扰,水土流失情况严峻,被称为世界水土流失之最。本文选取砒砂岩区具有典型代表性的阳崖小流域为研究对象,在ArcGis10.0操作平台下,以30m分辨率的DEM数据为基础对流域内的沟道进行提取；通过对2013年遥感影像进行解译,获取了流域2013年的土地利用现状图；对流域内的植被现状进行外业调查；参照我国《1：100万土地资源图》土地潜力评价系统对研究区内土地利用潜力进行评价,并结合实地情况对流域内坡面、沟沿、沟道以及河岸进行植被缓冲带的布局与配置。主要研究结论如下：(1)流域内一级沟道数量多,致使水流集中的速度快；沟道密度大,使得地表径流大量汇集,水流流量增大。因此,流域内沟道数量多、密度大,一级沟道多,所占比重大是流域内土壤侵蚀严重的重要原因。(2)对流域内土地类型和植被现状进行了调查。通过对地形因子坡度、坡向的提取与分析,揭示出流域内地形条件差,坡度主要集中在5-15°,坡向以阳坡、半阳坡为主,用作农用地的改良难度大,适宜用为林业用地或牧草地。对土地利用现状的分析说明流域内土地利用结构不合理,未利用地占到流域总面积的45.52%,且主要为侵蚀沟道两侧的裸岩与裸地。此外,流域内的植被覆盖度低,种类单一,主要为灌木和草本植物,乔木数量少且以人工林为主,应该通过布设植被缓冲带增加流域内植被盖度和生物多样性,从而达到防治侵蚀的目标。(3)依据土地潜力评价系统建立土地利用潜力评价表,根据最弱指标对评价单元的限制作用最大的原则对流域内土地潜力进行评价,结果表明流域内主要为Ⅲ级和Ⅳ级地,共占流域总面积的78.62%,且主要分布在沟坡以及坡面上,应充分挖掘这部分土地的利用潜力,通过土地利用结构的调整把其用作林业用地或牧草地来达到控制土壤侵蚀,增加生态经济效益的目的。(4)依据土地潜力评价结果以及土地利用现状对流域进行植被缓冲带的布局与配置。缓冲带主要分布在坡面、沟沿、沟道(沟底、沟坡和溯源侵蚀强烈的沟头)以及河岸。结合立地条件选择适宜的植被和整地方式,共设计了油松+柠条、油松+山杏、沙棘+山杏三种带状混交模式和沙棘纯林、油松纯林、以及柠条纯林三种纯林模式。
[Abstract]:Due to its own erodibility, severe natural conditions such as high drought wind and concentrated rainfall, and the disturbance of human factors, the soil and water loss situation in the arsenopyst area is severe, so it is called the most serious soil erosion in the world. In this paper, the typical representative Yangya small watershed in the soft rock area is selected as the research object, and the channel in the basin is extracted on the basis of 30m resolution DEM data under the ArcGis10.0 operating platform. Through the interpretation of the remote sensing image in 2013, the land use status map of the watershed in 2013 was obtained, and the vegetation status in the basin was investigated in the field. According to the land potential evaluation system of < 1: 1 million land resources map in China, the potential of land use in the study area is evaluated, and the distribution and disposition of vegetation buffer zone along the slope, gully, channel and riverbank in the river basin are analyzed in combination with the actual situation. The main conclusions are as follows: (1) the number of first-order channels in the basin is large, which results in the rapid concentration of water flow, and the high channel density leads to a large amount of surface runoff and the increase of water flow. Therefore, the number and density of channel in the watershed are large, and the proportion of the first channel is large, which is the important reason for the serious soil erosion in the basin. (2) the land types and vegetation status in the basin are investigated. Through the extraction and analysis of the slope and direction of the topographic factors, it is revealed that the terrain condition in the basin is poor, the slope is mainly concentrated in 5-15 掳, the slope direction is mainly sunny slope and semi-sunny slope, so it is difficult to improve agricultural land. Suitable for forestry land or forage land. The analysis of the present situation of land use shows that the structure of land use in the basin is unreasonable, the unused land accounts for 45.52% of the total area of the basin, and it mainly consists of bare rock and bare land on both sides of the erosion channel. In addition, the vegetation coverage in the watershed is low, the species is single, mainly shrubs and herbaceous plants, and the number of trees is small and the artificial forest is the main one. Therefore, vegetation coverage and biodiversity should be increased by planting vegetation buffering zones. In order to achieve the goal of controlling erosion. (3) according to the land potential evaluation system, the evaluation table of land use potential is established, and the land potential in the watershed is evaluated according to the principle that the weakest index has the most limiting effect on the evaluation unit. The results show that there are mainly 鈪，
本文编号：2364997
[Abstract]:Due to its own erodibility, severe natural conditions such as high drought wind and concentrated rainfall, and the disturbance of human factors, the soil and water loss situation in the arsenopyst area is severe, so it is called the most serious soil erosion in the world. In this paper, the typical representative Yangya small watershed in the soft rock area is selected as the research object, and the channel in the basin is extracted on the basis of 30m resolution DEM data under the ArcGis10.0 operating platform. Through the interpretation of the remote sensing image in 2013, the land use status map of the watershed in 2013 was obtained, and the vegetation status in the basin was investigated in the field. According to the land potential evaluation system of < 1: 1 million land resources map in China, the potential of land use in the study area is evaluated, and the distribution and disposition of vegetation buffer zone along the slope, gully, channel and riverbank in the river basin are analyzed in combination with the actual situation. The main conclusions are as follows: (1) the number of first-order channels in the basin is large, which results in the rapid concentration of water flow, and the high channel density leads to a large amount of surface runoff and the increase of water flow. Therefore, the number and density of channel in the watershed are large, and the proportion of the first channel is large, which is the important reason for the serious soil erosion in the basin. (2) the land types and vegetation status in the basin are investigated. Through the extraction and analysis of the slope and direction of the topographic factors, it is revealed that the terrain condition in the basin is poor, the slope is mainly concentrated in 5-15 掳, the slope direction is mainly sunny slope and semi-sunny slope, so it is difficult to improve agricultural land. Suitable for forestry land or forage land. The analysis of the present situation of land use shows that the structure of land use in the basin is unreasonable, the unused land accounts for 45.52% of the total area of the basin, and it mainly consists of bare rock and bare land on both sides of the erosion channel. In addition, the vegetation coverage in the watershed is low, the species is single, mainly shrubs and herbaceous plants, and the number of trees is small and the artificial forest is the main one. Therefore, vegetation coverage and biodiversity should be increased by planting vegetation buffering zones. In order to achieve the goal of controlling erosion. (3) according to the land potential evaluation system, the evaluation table of land use potential is established, and the land potential in the watershed is evaluated according to the principle that the weakest index has the most limiting effect on the evaluation unit. The results show that there are mainly 鈪，
本文编号：2364997
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