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为探究甘肃平凉市崆峒区河道建设管理问题状况,基于崆峒区河道现状,对河道生态建设管理中的问题进行总结,提出远期发展对策。分析结果认为：崆峒区河道生态治理中主要存在突出工程效益,忽略了河道生态赋性及水系连通和护岸的景观价值,大部分护岸工程均为砼挡墙式结构,“渠化”“硬化”过多,河流水域岸线管理基础薄弱等问题。针对河道治理及管理问题,应从重视河湖水系连通、河道生态修复和保护、注重护岸的景观价值及水文化元素在工程建设中的应用和加大河道管护的资金投入机制等方面加强治理及管理,补齐河湖监管的短板弱项。分析结果为后期河道建设管理提供参考依据。 相似文献
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在城市河流生态治理中为修复生态系统环境,创造良好的动植物栖息空间和聚集地,尽可能的满足人们对河道宜居环境、人文景观的亲水性要求,提出河道底泥与水质治理、重新设计河道斜堤、发挥生态群落和水生植物吸附作用等水生态一体化技术。通过仿真试验的环境模拟,验证了生态治理技术体系的有效合理性,试验表明:基于河道景观修复、水质治理和斜堤重新设计的水生态治理措施恢复了河流的生态系统,可为太子河水资源保护和河流生态治理规划提供一定的决策依据。 相似文献
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大荔洛河生态治理首先在保证洛河大荔县城区段防洪安全的前提下,重在改善河道环境,营造良好区域环境,以打造绿色生态河流为主要目标。以“水”为脉,以“绿”为网,构筑生态化、自平衡的人居体系,形成“疏密有致,蓝绿相间”的布局形态。在保证河道生态用水的前提下,通过水生态环境治理,适当规划河湖人工水系和绿色景观,实现水资源的综利用。 相似文献
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河流生态修复技术研究概述 总被引：2，自引：0，他引：2
河流在人类社会发展中扮演着重要的角色,但由于人类的过度使用以及随意将污染物排放入河流中,造成河流的生态破坏、水体污染.对于河流的治理,国外已从传统的“污水处理、达标排放”治理目标转变为以水质再生为核心的“水的循环再利用”,由单纯的“污染控制”技术发展为“水生态的修复与恢复”.本文介绍了河流生态修复的理念及其修复技术. 相似文献
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“峡谷丹山”是内外地质营力共同作用而形成的多成因地貌组合,不仅具有非常高的景观价值,而且具有重要的科学价值。青海省化隆县拉木峡为黄河一级支流,发育典型的角度不整合和丹霞地貌,因而成为青藏高原隆升和黄河形成演化研究的良好区域。以该地貌组合类型的形态特征、成因机制及形成年代研究为目标,采用野外地质调查等方法,对组成峡谷的岩石及地层、构造背景开展研究,系统总结与分析拉木峡地貌景观的形成动力和演化过程,进而探讨其对青藏高原隆升及黄河演化的指示意义。拉木峡由约900 Ma前的新元古代化隆岩群片麻岩及角度不整合于其上的约54 Ma前的新生代古近纪西宁群红色砂砾岩层组成。约8 Ma前青藏高原快速隆升,丹霞地貌雏形开始形成。自1.1 Ma黄河贯通化隆盆地后,受拉木峡流水强烈侵蚀下切和重力崩塌的持续作用,发育“峡谷丹山”地貌组合景观。峡谷险峻幽深、丹霞栩栩如生,成为极具典型性、独特性和稀有性的国家级地质遗迹,对青藏高原隆升、黄河形成演化和新生代气候环境的研究具有重要价值。 相似文献
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The Yangtze, the longest river in Asia, was hypothesized to be assembled through a series of Cenozoic capture events, such as the reversal of Middle Yangtze River and the capture of Upper Yangtze River, but the history remains largely unknown. Here, we present new geomorphic observations in the structural context of the eastern Sichuan Basin, namely the Eastern Sichuan fold belt, and identify an important drainage divide along the “midline” of this arc-shape fold belt. Based on longitudinal profile analysis, we find that the river capture events more likely occurred in the syncline valleys of low-relief landscape. Our results yield a new perspective on Middle Yangtze River reversal, and we propose that the “midline” drainage divide, rather than the Three Gorges, was the starting site of Middle Yangtze River reversal. In this manner, the reversal could have been accomplished by a sequence of river reversal over range-parallel segments in syncline valleys with less impact on the pre-existing drainage system in eastern Sichuan Basin. 相似文献
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为了改变传统滑坡遥感技术方法效率低、调查精度难以提高的状况,经多年实践与探索,笔者于 1999 年提出了“数字滑坡”概念。该概念使传统的“地学滑坡”拓展为能以数字形式表达的,具有三维空间、“多维”时间信息的,由“多元”要素组成的“数字滑坡”。数字滑坡技术系统由滑坡解译基础技术、遥感识辨滑坡技术、滑坡数据库及滑坡模型4部分构成。多年来,数字滑坡技术已成功应用于我国大型水电站建设、山区交通线建设、区域开发环境治理以及抗震减灾等领域,也用于大规模个体滑坡调查研究,并取得了显著的经济和社会效益,有效服务于国家防灾减灾战略。该文主要以西藏帕里河及川东天台乡2个典型滑坡调查为例,阐述数字滑坡技术的创新应用。 相似文献
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基于孢粉、炭屑显微结构、古土壤遥感资料,并结合西辽河流域文化景观的时空格局,探讨了人地关系相互作用机制.历史时期西辽河流域的环境变化有两个适宜期和两个欠适宜期,与此相适应,文化景观则表现为农业文化的3次兴盛:上古农业文化兴盛期;中古农业文化兴盛期;近代农业文化兴盛期.在这3个农业兴盛期中,人类生态足迹逐渐扩大,对资源的利用程度逐渐加强,对该区域的景观面貌的影响逐渐增大.西辽河流域景观演变不表现为简单的南北摆动,而是表现为区域尺度上景观的"弹性变化". 相似文献
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Lucie Juřičková Jitka Horáčková Vojen Ložek Michal Horsák 《Boreas: An International Journal of Quaternary Research》2013,42(4):932-946
Analyses of fossil mollusc successions have rarely been used to study the development of floodplain forests during the Holocene. The Oh?e River, located in a prehistorically settled chernozem area in the Czech Republic, is partly situated in Cretaceous marlstones, yielding sediments suitable for fossilization directly in floodplain deposits. We analysed five fossil mollusc successions situated in the lower stretch of the Oh?e River and compared the results with recent mollusc assemblages studied along the entire 256 km of the river. Fossil samples were composed mostly of open‐country species throughout the Holocene or the whole preserved succession. Only some samples also contained woodland assemblages, but these were always greatly impoverished, with a very low frequency of strictly woodland species. Although the natural‐looking appearance of the present‐day floodplain forests of the lower river stretch has resulted in its being declared a nature reserve, modern floodplain forest mollusc assemblages there are also impoverished. This reduction in the distribution of strictly woodland species compared with modern assemblages in the upper stretch of the river seems to be the result of an ancient human settlement and continuous disturbances of the floodplain forest development since the Neolithic. Thus, fully developed floodplain forest assemblages occur recently only in the upper non‐impacted stretch of the river. Based on the studied fossil successions we can conclude that the lower Oh?e River floodplain was probably a mosaic of open and disturbed forest habitats throughout the Holocene. This area is part of a central European landscape island, where forests probably never fully developed and open patches from the early Holocene continually developed into an agricultural landscape. 相似文献
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黄海、渤海陆架区可见黄河三角洲沉积的形成时代 总被引：8，自引：1，他引：7
对于黄河形成史的研究存在两种不同的意见,其一认为黄河在第三纪以前就已出现;其二认为黄河在晚更新切末期才最终得以贯通。黄河的贯通与青藏高原隆起密切相关,黄河不可能在海拔较高的源头出现之关就已存在。冰期海退时期的陆架不存在类似现在的黄河。现代长江口以北地区在末次冰期 非常恶劣的自然环境,部分地区为冻土带分布区,部分地区为古沙漠活动区。 相似文献
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《Geoforum》2015
This article examines changing water governance modalities in the context of the neoliberalization of nature. Specifically, it focuses on Brazilian water sector reforms passed in 1997 that mandate decentralized and participatory decision-making at the river basin scale. Critics have suggested that rescaling, decentralization, and participatory governance mechanisms – supposedly intended to render decision-making more equitable, accessible, and relevant – can serve to legitimate, facilitate, and thus further embed processes of neoliberalization. Examining the impact of Brazil’s water sector reforms on the state–society relationship, this article presents a case study of water governance in the São Francisco River Basin and finds that the reforms – despite their neoliberalizing potential – have not significantly contributed to the neoliberalization of governance therein. Instead, water governance continues to be characterized by longstanding patterns of traditional elite control. Through an institutional and socio-natural analysis, this article describes and accounts for the continued dominance of these patterns relative to neoliberalization and explores activists’ efforts to use water sector reforms to pursue more progressive possibilities. The article concludes with a discussion of the implications for variegation and contestation in ongoing debates over neoliberal natures. 相似文献
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以金沙江石鼓-巧家河段与川江宜宾-重庆丰都河段的阶地堆积物物质成分变化为着眼点研究了长江上游水系变迁。分河段对阶地堆积物重矿物成分进行时空对比后发现,金沙江下段沿岸各地的高位阶地重矿物成分差异较大,说明当时该地区尚未有贯通的金沙江,而可能是独立的小水系。白汉场、剑川、漾濞、元江等地古河谷堆积物样品重矿物成分的相似说明古金沙江可能是在石鼓、鸿文附近向南经过白汉场-剑川-漾濞盆地入红河的。川江各处高位阶地重矿物成分的差异说明当时该地区也存在分散的水系。金沙江下段以及川江贯通之后汇水东流,现代长江上游水系格局形成,并发育了重矿物成分相近的低阶地。 相似文献
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源汇系统（Source- to- sink system）是将物源区的构造剥蚀、沉积物输送区的沉积物搬运和沉积区的沉积物堆积等视为一个完整系统。沉积物的源区恢复和附近水系重建是源汇研究的热点问题，沉积物碎屑锆石U- Pb定年是源汇系统研究的有效方法之一。南海北部与其周边地区构成了一个完整的源汇系统，通过源汇分析可获得南海北部各盆地沉积物来源及周边主要河流的演化历史。本文通过总结前人在南海北部主要盆地新生代沉积物碎屑锆石U- Pb研究成果，探讨珠江、红河和昆莺琼古河的新生代演化历史。珠江最早的支流北江和东江形成于早渐新世，晚渐新世溯源到西江上游的红水河、左江和右江，中新世溯源到西江中游柳江、桂江和上游的北盘江、南盘江。在晚白垩世—古近纪红河属于青藏高原东缘大型向东南或向南流河流的一部分，之后由于地貌变化形成现今红河。昆莺琼古河在早渐新世开始发育影响到珠江口盆地，在晚渐新世昆莺琼古河雏形已经基本形成，中新世起昆莺琼古河可能向西有一定程度的退缩。 相似文献