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911.
L.T. Silva F. Fonseca D. Rodrigues A. Campos 《Journal of Environmental Planning and Management》2018,61(3):535-552
The impact of traffic noise can be prevented by suitable planning measures. This study analyses the relationship between urban geometry and traffic noise, recognizing that the arrangement of buildings and streets greatly influences urban noise. The study was carried out in Braga, a medium-sized Portuguese city, by selecting locations with different urban geometries. At each site, the equivalent continuous sound level was measured. Furthermore, the urban geometry was evaluated by using the sky view factor, a parameter which shows the degree of sky obstructed by buildings. Results show an inverse proportionality between noise and the sky view factor. The highest noise levels were found in areas with a low sky view factor. The results also indicate that the sky view factor is a parameter which can potentially be used in research on urban noise. 相似文献
912.
跨境流域生态补偿机制的构建,是实现"一带一路"倡议目标的重要基础,有助于化解资源冲突、协调区域发展、增进利益协同,进而增强政治互信,加快经济融合,提升文化包容,推进命运共同体构建。本文基于对西方国家跨境流域生态补偿研究与实践的梳理,总结归纳出西方跨境流域生态补偿中强调流域生态系统分析、注重不同付费原则相互配搭、重视双/多边协商、建立多层次综合管理体系等经验。在此基础上,针对现阶段中国跨境流域生态补偿所面临的挑战,提出加强跨境协商合作平台建设、重视对跨境流域生态系统研究以及构建多层次协同管理体系等应对措施。 相似文献
913.
Culture as trigger for sustainability transition in the water domain: the case of the Spanish water policy and the Ebro river basin 总被引:2,自引:2,他引:0
There is a mounting body of literature dealing generally with the dynamics of transitions of human systems towards sustainability
and specifically with the different stages and processes of transitions. However, the question of why transition processes
occur in the first place remains largely unexplained. This paper explores the concept of transition triggers, such as culture
or material resource scarcity, and provides a theoretical framework to explain the emergence of a transition and its relation
to recent developments in Spanish water policy. We adapt the general framework provided by current transition theory and gather
empirical evidence and insights from processes occurring within the Spanish policy context and the Ebro river basin in particular.
Our results show that the sole existence of biophysical limits to water use or development cannot explain the start of a possible
sustainability transition in this domain in Spain. Changes in the existing water policies in the direction of sustainability
were not ignited by people directly affected by water scarcities but by a coalition of sensitive agents, mostly from academia,
NGOs and local constituencies, who managed to articulate new identities, integrate multiple sources of policy relevant knowledge,
and develop new values under the umbrella of the new water culture movement.
相似文献
Akgun IlhanEmail: |
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917.
北武夷梨子坑火山盆地流纹斑岩与铅锌矿的成因关系 总被引:2,自引:0,他引:2
梨子坑火山盆地位于北武夷中生代月凤山—梨子坑火山岩带东段,已知铅锌(铜、银)矿体或矿化呈细脉-浸染型、脉状,产于流纹斑岩脉的内外接触带及其外侧围岩中,发育钾化、绿泥石化、硅化、绿帘石化等围岩蚀变。地球化学特征显示流纹斑岩为钙碱性系列,岩石具有高SiO2、富碱、高K2O、高钙铁、低镁、K2O/Na2O值偏高的特点,为强过铝质岩石。w(ΣREE)值为76.28×10-6~222.54×10-6,ω(ΣLREE/ΣHREE)比值较大,为4.08~12.30,属于轻稀土元素富集型。成矿流纹斑岩形成于137±2.1Ma(SHRIMP锆石U-Pb法)~138.8±1.4Ma(LA-MC-ICPMS锆石U-Pb法),属早白垩世。铅锌矿属于次火山斑岩脉型铅锌(银铜)成矿系列,划分为次火山斑岩脉型和次火山热液破碎带型两种矿床成因类型。 相似文献
918.
Abstract: Interfaces between terrestrial and stream ecosystems often enhance species diversity and population abundance of ecological communities beyond levels that would be expected separately from both the ecosystems. Nevertheless, no study has examined how stream configuration within a watershed influences the population of terrestrial predators at the drainage‐basin scale. We examined the habitat and abundance relationships of forest insectivorous birds in eight drainage basins in a cool temperate forest of Japan during spring and summer. Each basin has different drainage‐basin geomorphology, such as the density and frequency of stream channels. In spring, when terrestrial arthropod prey biomass is limited, insectivorous birds aggregated in habitats closer to streams, where emerging aquatic prey was abundant. Nevertheless, birds ceased to aggregate around streams in summer because terrestrial prey became plentiful. Watershed‐scale analyses showed that drainage basins with longer stream channels per unit area sustained higher densities of insectivorous birds. Moreover, such effects of streams on birds continued from spring through summer, even though birds dispersed out of riparian areas in the summer. Although our data are from only a single year, our findings imply that physical modifications of stream channels may reduce populations of forest birds; thus, they emphasize the importance of landscape‐based management approaches that consider both stream and forest ecosystems for watershed biodiversity conservation. 相似文献
919.
滇池及其流域生态建设既是生态问题,也是经济问题,必须用经营的理念来进行治理和保护。流域要调整产业格局,“农田退耕造林,村庄闭合治污,产业退二进三”;要开展“厕所革命”、“餐饮革命”和“垃圾革命”,实现城市废弃物资源化利用;入湖河道要打造为生态景观河道;湖体可开发湿地公园旅游、水上游玩、底泥资源化利用等项目,还可种植水生花卉、水生蔬菜和养殖生态鱼类。 相似文献
920.
In this paper, stormwater runoff from an urban watershed with combined sewer systems located in Daejeon metropolitan city, Korea, was characterized to measure the stormwater runoff discharge rates and pollutant concentrations. The observed averaged event mean concentrations (EMCs) of combined sewer overflows (CSO) were 536.1mg TSS/L, 467.7 mg TCODcr/L, 142.7 mg TBOD/L, 16.5mg TN/L, and 13.5mg TP/L. A detention basin was proposed to reduce CSO, and its essential design elements were discussed. The first flush significantly affected contaminant constituents in the descending order of suspended solid>organics>nutrients. Storage volumes for containing the first flush to improve water quality of the receiving stream can be estimated based on the total suspended solid loading. In this study, detention of the first flush equivalent to 5mm of precipitation could reduce CSO-induced diffuse pollution loading to a receiving water body by up to 80% of the total suspended solid loading. 相似文献