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21.
In Latin America and the Caribbean, river restoration projects are increasing, but many lack strategic planning and monitoring. We tested the applicability of a rapid visual social–ecological stream assessment method for restoration planning, complemented by a citizen survey on perceptions and uses of blue and green infrastructure. We applied the method at three urban streams in Jarabacoa (Dominican Republic) to identify and prioritize preferred areas for nature-based solutions. The method provides spatially explicit information for strategic river restoration planning, and its efficiency makes it suitable for use in data-poor contexts. It identifies well-preserved, moderately altered, and critically impaired areas regarding their hydromorphological and socio-cultural conditions, as well as demands on green and blue infrastructure. The transferability of the method can be improved by defining reference states for assessing the hydromorphology of tropical rivers, refining socio-cultural parameters to better address river services and widespread urban challenges, and balancing trade-offs between ecological and social restoration goals.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01565-3. 相似文献
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在环境法中,要了解生态修复的属性。目前,业界关于生态修复的研究还处于初级阶段,掌握生态修复的含义,了解生态修复与法律之间的关系,才能进一步探讨生态修复的环境法属性。在生态修复上,政府起到极其重要的作用,政府要加强对环境的保护,使生态修复能够真正落到实处,并严格依据环境法的要求及时追究侵害人的责任。 相似文献
25.
Sargaonkar A 《Environmental monitoring and assessment》2006,117(1-3):491-503
Non-point source (NPS) pollution is the result of various land use practices such as agriculture, sites of construction and
waste disposal, urban development and so on. The control of NPS pollution is possible by regular monitoring and assessment
on watershed basis to educate people for implementing well-known structural and non-structural measures. Recent trend is to
use GIS based modelling tool for assessment of rainfall-runoff and non-point loading. The approach requires generation and
analysis of basin wide data on various features of land and estimates of Event Mean Concentrations (EMCs) of pollutants in
the runoff. In the present paper, basin wide data in different districts of Tapi basin has been analysed for land use distribution;
fertilizer application; low, medium and high-density habitation; and annual rainfall. Coefficients of runoff have been estimated
considering pervious and impervious area for different land use types, and compared with the reported values for Indian conditions.
The estimated mean annual runoff flow indicated that two districts Jalgaon and Dhule contribute maximum runoff to the Tapi
River. Estimates of EMCs for BOD and nutrients (N and P) in the runoff from various districts are useful in GIS-based modelling
study for NPS pollution assessment. 相似文献
26.
以1961~2007年三江源区的气象及径流资料为基础,采用M K法和R/S分析法分析三江源区气候及水文要素变化趋势及进行未来变化趋势预测,并采用主成分分析法判定径流过程的主要驱动要素。研究表明:三江源区气温普遍显著升高,水面蒸发和地温随着气温的升高也不断增加,降水的增加并不显著,而年径流尤其是夏秋季节径流存在明显减小的趋势。R/S分析结果表明气候和水文要素未来总体的变化趋势与过去一致。三江源区径流过程是由气温起主导作用,径流对气温变化较降水变化更为敏感。本研究将为三江源区水资源开发利用及优化配置提供科学借鉴,同时为三江源区的生态建设和保护提供参考依据 相似文献
27.
贵州喀斯特土石山区水土保持生态经济型植被恢复模式 总被引:9,自引:0,他引:9
以贵州省喀斯特土石山区为例,通过总结前人的研究成果和中国科学院亚热带农业生态研究所喀斯特生态实验站的部分试验数据,从全局性、紧迫性、高效性、层次性、可持续性、创新性与多样性的角度提出了在贵州喀斯特土石山区的急坡地、陡坡地、缓陡坡地其水土保持生态经济型植被恢复模式分别采用3种典型模式,即:灌草模式,乔灌草模式与林果模式,以期促进该区域的生态、经济与社会的全面协调与可持续发展。 相似文献
28.
退化河流滨岸带生态系统修复及其评价是目前国内外学者研究的热点,也是修复生态学、流域生态学等学科研究的重要内容之一。河流滨岸带生态修复工作的开展必须建立在掌握滨岸带结构及其生态功能的基础上。河流滨岸带生态系统退化成因和驱动机制研究是进行滨岸带生态修复工作的前提;生态系统修复是滨岸带研究的重点和关键,必须遵循自然法则,以修复生态功能为最终目标;河流滨岸带生态系统的修复过程和效果应该建立适宜的评价方法和管理策略来确定。加强河流滨岸带退化机制的理论研究及3S技术的应用,从景观和流域尺度开展滨岸带生态修复的研究和实践工作,着重进行平原河网地区河流滨岸带生态修复的研究和实践工作等将是中国今后相关研究的重点。 相似文献
29.
Hobbs R 《Journal of environmental management》2009,90(9):2857-2865
In the latter half of the 20th century, native pine woodlands in Scotland were restricted to small remnant areas within which there was little regeneration. These woodlands are important from a conservation perspective and are habitat for numerous species of conservation concern. Recent developments have seen a large increase in interest in woodland restoration and a dramatic increase in regeneration and woodland spread. The proximate factor enabling this regeneration is a reduction in grazing pressure from sheep and, particularly, deer. However, this has only been possible as a result of a complex interplay between ecological, political and socio-economic factors. We are currently seeing the decline of land management practices instituted 150-200 years ago, changes in land ownership patterns, cultural revival, and changes in societal perceptions of the Scottish landscape. These all feed into the current move to return large areas of the Scottish Highlands to tree cover. I emphasize the need to consider restoration in a multidisciplinary framework which accounts not just for the ecology involved but also the historical and cultural context. 相似文献
30.
Pyrethroid pesticides occur in urban creek sediments at concentrations acutely toxic to sensitive aquatic life. To better understand the source of these residues, runoff from residential neighborhoods around Sacramento, California was monitored over the course of a year. Pyrethroids were present in every sample. Bifenthrin, found at up to 73 ng/L in the water and 1211 ng/g on suspended sediment, was the pyrethroid of greatest toxicological concern, with cypermethrin and cyfluthrin of secondary concern. The bifenthrin could have originated either from use by consumers or professional pest controllers, though the seasonal pattern of discharge from the drain was more consistent with professional use as the dominant source. Stormwater runoff was more important than dry season irrigation runoff in transporting pyrethroids to urban creeks. A single intense storm was capable of discharging as much bifenthrin to an urban creek in 3 h as that discharged over 6 months of irrigation runoff. 相似文献