高原城镇河道演变与生态护岸措施

River channel evolution and ecological revetment measures in plateau towns

为促进高原城镇可持续发展,改善传统硬质护岸破坏高原脆弱的水域生态系统结构和城市景观环境现状,选取林芝市八一镇河道为研究对象,基于1970年、1982年、2009年、2014年地形图对尼洋河八一镇河段河道演变特征和生态护岸措施进行分析。结果表明,尼洋河八一镇河段河床具有明显的游荡特征,河道心滩发育、洲汊纵横、主流摆动频繁,致使堤防维护和加固难度凸显;结合林芝市八一镇硬质型护岸现状生态改造需要,应从尊重民族文化、遵守自然法则、采用原生材料、营造滨水景观、去直改缓、注重生物多样性的设计角度出发,综合采用植物护岸、松木桩-抛石生态护岸、生态格网挡墙、混凝土砌块护岸、生态混凝土护岸等生态护岸形式。

With the section of the Niyang River in Bayi Town of Nyingchi City used as an example,this study was conducted to alleviate the damages of traditional rigid revetments to fragile river ecology and the landscape environment in plateau regions,and to promote the sustainable development of plateau towns.The analysis of river evolution in Bayi Town according to aerophotographic maps of 1970,1982,2009,and 2014 shows that the river section has obvious characteristics of riverbed wandering,heart beach development,complicated distributions of islands and branches,and frequent swing of the main stream,leading to significant difficulties in embankment reinforcement.Results also show that the ecological reconstruction of rigid revetments in Bayi Town,Nyingchi City,should be undertaken based on the design concepts of respecting the culture of ethnic minorities,following natural laws,using autochthonous materials,creating waterfront landscape,transforming straight walls to gradual slopes,and protecting biodiversity,and the ecological revetment forms,including plant revetments,pine pile-riprap revetments,stone cage retaining wall revetments,precast concrete block revetments,and ecological concrete revetments should be comprehensively used.