采用RTKGPS测量技术与方法,2006~2008年连续三年共9次对我国海岸沙丘主要分布区域之一的河北昌黎黄金海岸翡翠岛的一个典型海岸横向沙脊进行了三个横剖面的高精度观测。海岸横向沙脊高程、断面及其典型位置的观测结果表明,观测期间海岸横向沙脊脊顶和背风坡坡脚夏秋季东移、冬春季节西移,脊顶总体向西移动,年均最大移距1.83m,但同期观测剖面背风坡坡脚的移动距离最大仅0.16m;脊顶高程夏秋季降低、冬春季升高,观测期间脊顶高程平均降低了1.58m,而三个观测剖面的断面面积期间则分别增加了0.47%、0.79%和0.69%,故海岸横向沙脊移动与形态变化的季节性十分明显,总体上具有沙丘下部基本稳定、顶部以往复前进方式向陆缓慢移动以及沙体加积增大但脊顶高程逐渐降低的特征,其原因主要与区域风况特点及人类活动密切相关。
By use of high-precision RTKGPS technology and survey method, three profiles of a typical coastal transverse ridge were surveyed 9 times in the three years from 2006 to 2008. The typical coastal transverse ridge is located at Feicui Island of Changli Gold Coast in Hebei Province, which is one of the most typical coastal aeolian distribution regions in China and famous for the tall and typical coastal transverse ridges. The surveying data, which is about height and profile section as well as the typical topographic positions of coastal transverse ridge, could be used to explain the movement and topographic change of coastal transverse ridge. In the period of field observation from 2006 to 2008, the position of crest and the leedward slope bottom at the survey profiles of coastal transverse ridge advanced towards sea in the direction of east in summer and autumn and moved towards inland in the direction of west in winter and spring, in general the crest of coastal transverse ridge moved towards inland in the direction of west, and its annual largest movement distance in the period of field observation was 1.83 meters, but the annual largest movement distance of the leeward slope bottom in the same period was just 0.16 meters. It was found that the height of crest at the survey profiles of coastal transverse ridge decreased in summer and autumn and increased in winter and spring, the mean height of crest of coastal transverse ridge in the period of field observation reduced by 1.58 meters. The section area of the surveyed profiles of coastal transverse ridge increased by 0.47%, 0.79% and 0.69%, respectively. According to the surveying data above, it could be concluded that the movement and topographic change of coastal transverse ridge are closely related with the seasonal change, indicating that the stable bottom of coastal transverse ridge is characterized by slow advance to inland in the way of to-and-fro of crest, the aggrandizement of volume and reduction of height of crest of coastal transverse ridge. This res