强人类活动干扰下的平原区数字水系构建

由于满足人类生产生活的需求,人类对河道的开发利用使得河道水系变得纵横交错,在平原区的很多河道高程不断的变化,甚至河流流向变成了与原来相反;因此采用常规方法在利用DEM提取数字水系时就会产生断开或者假水系的情况.针对以上情况,本文建立了采用强可视化算法等方法进行DEM的处理及河系提取,具体为:首先在流域实际水系的基础上,提炼出可反映实际水系主要特征和过程的概化水系,其次对断开或不舍理处的DEM采用本文建立的强可视化算法进行分析,并采用缓冲区算法和双线性插值算法进行修改,最后对得到的DEM进行河系提取.运用以上方法,本文以天津市为倒进行了应用,并与传统算法和高程增量遮加方法提取的DEM水系相比较,结果表明该方法更适合平原区数字水系的提取,并能得到与实际情况吻合的水系.

Extraction of Digital River System in Plain Areas Affected by Human Activities

With the development of society, the river plain water effected by human activities has become the constant criss-crossing,the basin water cycle has changed, and the digital river extracted from its DEM became some shortages,such as disconnect or distortion.A strong visualization algorithm approach was developed in this paper to solve the problems. Firstly, according to the actual situation of river system,the digital elevation models(DEM) was pretreated by blocking up its basic values and using the method of iterative elevation increment advanced by Martz and Garbrecht.Secondly, through interactive analysis between simulating river system and abstracted river system by said pretreatments, some disconnected and illogical rivers were found,then analyzed by strong visualization algorithm which updated by us and buffer zones arithmetic,and its DEM was modified by double lines insert algorithm. The method was applied in Tianjin city,and the result indicates it makes a better river system than river system abstracted by traditional algorithm or models.