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81.
Evolution of a Mediterranean Coastal Zone: Human Impacts on the Marine Environment of Cape Creus 总被引:1,自引:0,他引:1
This study presents an integrated analysis of the evolution of the marine environment and the human uses in Cape Creus, a
Mediterranean coastal area where intense commercial fisheries and recreational uses have coexisted over the last fifty years.
The investigation synthesizes the documented impacts of human activities on the marine environment of Cap de Creus and integrates
them with new data. In particular, the evolution of vulnerable, exploited species is used to evaluate the fishing impacts.
The effects of area protection through the establishment of a marine reserve in the late 1990s and the potential climate change
impacts are also considered. The evolution of the human uses is marked by the increasing socioeconomic importance of recreational
activities (which affect species and habitats) in detriment to artisanal and red coral fisheries (which principally affect
at a species level). Overall, populations of sedentary, vulnerable exploited species, hard sessile benthic invertebrates,
and ecologically fragile habitats, such as seagrass meadows, the coralligenous and infralittoral algal assemblages have been
the most negatively impacted by anthropogenic activities. Albeit human uses currently constitute the largest negative impact
on the marine environment of Cap de Creus, climate change is emerging as a key factor that could have considerable implications
for the marine environment and tourism activities. The establishment of the marine reserve appears to have had little socioeconomic
impact, but there is some evidence that it had some positive biological effects on sedentary, littoral fishes. Results demonstrate
that the declaration of a marine reserve alone does not guarantee the sustainability of marine resources and habitats but
should be accompanied with an integrated coastal management plan. 相似文献
82.
长白山区域旅游资源开发的几个问题 总被引:3,自引:0,他引:3
长白山区域是我国具有特色的地理单位,资源丰富,尤其旅游资源有着广阔的开发前景。本文是在深入调查和完成旅游规划的基础上,论述旅游开发的几个问题。 相似文献
83.
城市环境总体规划中大气环境红线内涵及划定技术 总被引:3,自引:0,他引:3
城市环境总体规划是一项重大环境管理制度创新,目前全国已启动了24个城市的环境总体规划编制工作,其中划定环境红线是城市环境总体规划的核心内容。本文结合福州、宜昌、平潭等城市环境总体规划编制实践,首次提出了大气环境红线的技术框架,将大气环境红线划分为源头布局敏感区、污染易聚集区及敏感的环境受体三类,并创新性建立了大气环境红线划定技术方法,初步构建了适用于城市环境总体规划的空间规划技术体系。 相似文献
84.
85.
Fenton试剂处理酸性玫瑰红B的研究 总被引:7,自引:0,他引:7
采用Fenton试剂处理酸性玫瑰红B染料废水,考察了FeSO4投加量、H2O2投加量、pH值和反应时间对处理效果的影响,研究了原水的氧化还原电位和TOC的变化规律,评价了它的可生化性。结果表明,最佳pH值为3,FeSO4的适宜投加量为8mmol/L,H2O2最佳投加量为50mmol/L,此时COD去除率和脱色率分别为77.1%和92.8%,处理后该染料废水的可生化性大大提高。 相似文献
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88.
Assessments of risk to biodiversity often rely on spatial distributions of species and ecosystems. Range‐size metrics used extensively in these assessments, such as area of occupancy (AOO), are sensitive to measurement scale, prompting proposals to measure them at finer scales or at different scales based on the shape of the distribution or ecological characteristics of the biota. Despite its dominant role in red‐list assessments for decades, appropriate spatial scales of AOO for predicting risks of species’ extinction or ecosystem collapse remain untested and contentious. There are no quantitative evaluations of the scale‐sensitivity of AOO as a predictor of risks, the relationship between optimal AOO scale and threat scale, or the effect of grid uncertainty. We used stochastic simulation models to explore risks to ecosystems and species with clustered, dispersed, and linear distribution patterns subject to regimes of threat events with different frequency and spatial extent. Area of occupancy was an accurate predictor of risk (0.81<|r|<0.98) and performed optimally when measured with grid cells 0.1–1.0 times the largest plausible area threatened by an event. Contrary to previous assertions, estimates of AOO at these relatively coarse scales were better predictors of risk than finer‐scale estimates of AOO (e.g., when measurement cells are <1% of the area of the largest threat). The optimal scale depended on the spatial scales of threats more than the shape or size of biotic distributions. Although we found appreciable potential for grid‐measurement errors, current IUCN guidelines for estimating AOO neutralize geometric uncertainty and incorporate effective scaling procedures for assessing risks posed by landscape‐scale threats to species and ecosystems. 相似文献
89.
论人口-资源-环境-灾害恶性循环的严重性与减灾工作的新阶段 总被引:6,自引:2,他引:4
人口、资源、环境、灾害.这是当今世界考虑人类的生存与发展的四大基本问题,目前均已发出“黄牌警告”.抑制社会与自然向恶性循环方向发展,需唤起全人类的觉醒和国家领导更高的责任感:保护环境和防御大灾.需组织国际交流与协作:协词社会的发展与生存.需促使环保减灾工作纳入发展规划;提高环保减灾的效能.需推动其内部机制走向综合化和社会化,这是90年代国际和国内共同奋斗的目标. 我国是四大基本问题最为严重的少数国家之一,本文列述了有关的一些重要资料,以求在严酷的四大“黄牌”的总况面前.激起社会更广泛的觉醒和行动.最后,简述了对减灾工作的一些设想. 相似文献
90.
采用溶胶 凝胶法(Sol Gel)制备了负载型纳米TiO2膜,分别考察了原料配比、pH值、煅烧温度对薄膜性质的影响,并利用XRD对其结构进行了表征,同时,用负载型TiO2膜对活性艳红X 3B(X 3B)模拟染料废水进行了微波辅助光催化脱色的研究。结果表明,改变原料配比及pH值可以制备出不同粒径的纳米TiO2膜,在450℃煅烧时TiO2呈锐态矿结构,在650℃以上出现锐态矿与金红石混晶结构,750℃时完全转变为金红石结构。所制得的纳米TiO2薄膜对X 3B具有较好的光催化活性。 相似文献