节点文献
陕北半干旱黄土区陡坡微地形分布规律
The Microrelief Distribution Law on Steep Slope in Semiarid Loess Area in North Shaanxi Province
【作者】 邝高明；
【导师】 朱清科；
【作者基本信息】 北京林业大学 ， 复合农林学， 2012， 硕士
【摘要】 微地形导致陕北半干旱黄土区坡面水分的异质性,因此按照微地形进行植被配置是解决该地区植被恢复困难问题的重要理论。本文选取陕西省吴起县合沟流域为研究对象,基于三维影像扫描全站仪、GIS、统计学等方法,研究黄土丘陵沟壑区陡坡微地形分布规律。研究结果表明：以卷尺测量值为参照,三维影像扫描全站仪测量的浅沟长度和陡坎宽度误差均在5%左右,能够满足本文对微地形研究的需要；五种微地形占坡面面积比例平均值从大大小依次为切沟8.44%、缓台6.66%、浅沟5.00%、陡坎1.53%、塌陷1.52%；陡坡坡面陡坎与塌陷占坡面面积比例上限介于2%-5%之间、浅沟与切沟占坡面面积比例上限介于5%-10%之间、缓台占坡面面积比例上限介于15%-20%之间；塌陷、浅沟和切沟占坡面面积比例整体表现为阳坡和半阳坡大于半阴坡和阴坡,陡坎占坡面面积比例表现为阴坡和半阳坡大于半阴坡和阳坡,而相反,缓台表现为半阴坡和阳坡大于阴坡和半阳坡；陡坎、浅沟和切沟占坡面面积比例随着坡度的增大而减小,塌陷占坡面面积比例随着坡度的增大而增大；田坎与沟缘线对塌陷、陡坎和缓台等三种微地形的面积、长度、汇流面积及上坡坡长等地形参数有不同的影响；按照微地形进行植被配置后能有较大比例的乔灌植被。
【Abstract】 The microrelief lead to soil moisture heterogeneity on slop,therefore,According to microrelief in configuring vegetation is an important theory to solve the difficult restoration of vegetation on steep slop in semiarid loess area in north Shaanxi Province.Choosing He Vally in Wuqi County,Shanxi Province as research object,based on3-d laser scanner, GIS and significant to research microrelief distribution in steep slope in loess hilly and gully region.The results showed that comaring with tape measure results, the error is about5%of shallow gully length and scarp width measured by3-d laser scannerwhi,ch is satisfied for researching microrelief;The area percentage of differerent microrelief,from big to small,are gully (8.44%), platform(6.66%), shallow gully (5.00%),scarp(1.53%) and collapse(1.52%).The area percentage upper of scarp and collapse is between2%-5%,gully and shallow gully is between10%-15%,platform is between15%-20%; the area percentage of collapse,gully and shallow gully shown as sunny slope and half-sunny slope are higher than half-shaded slope and shaded slope,however,it shows an opposite result of scarp area percentage. The area percentage of scarp,gully and shallow gully increases with slope gradient,and The area percentage of collapse decrease with slope gradient. The ridge and valley shoulder line have different effection on the terrain parameter,such as area,length,slope gradient and confluence area of collapse,scarp and platform; in addition, According to microrelief in configuring vegetation, arbor and shrub vegetation can take a big proportion.