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排序方式: 共有613条查询结果,搜索用时 218 毫秒
1.
Fishing‐gear restrictions and biomass gains for coral reef fishes in marine protected areas 下载免费PDF全文
Stuart J. Campbell Graham J. Edgar Rick D. Stuart‐Smith German Soler Amanda E. Bates 《Conservation biology》2018,32(2):401-410
Considerable empirical evidence supports recovery of reef fish populations with fishery closures. In countries where full exclusion of people from fishing may be perceived as inequitable, fishing‐gear restrictions on nonselective and destructive gears may offer socially relevant management alternatives to build recovery of fish biomass. Even so, few researchers have statistically compared the responses of tropical reef fisheries to alternative management strategies. We tested for the effects of fishery closures and fishing gear restrictions on tropical reef fish biomass at the community and family level. We conducted 1,396 underwater surveys at 617 unique sites across a spatial hierarchy within 22 global marine ecoregions that represented 5 realms. We compared total biomass across local fish assemblages and among 20 families of reef fishes inside marine protected areas (MPAs) with different fishing restrictions: no‐take, hook‐and‐line fishing only, several fishing gears allowed, and sites open to all fishing gears. We included a further category representing remote sites, where fishing pressure is low. As expected, full fishery closures, (i.e., no‐take zones) most benefited community‐ and family‐level fish biomass in comparison with restrictions on fishing gears and openly fished sites. Although biomass responses to fishery closures were highly variable across families, some fishery targets (e.g., Carcharhinidae and Lutjanidae) responded positively to multiple restrictions on fishing gears (i.e., where gears other than hook and line were not permitted). Remoteness also positively affected the response of community‐level fish biomass and many fish families. Our findings provide strong support for the role of fishing restrictions in building recovery of fish biomass and indicate important interactions among fishing‐gear types that affect biomass of a diverse set of reef fish families. 相似文献
2.
San Vicente Bay is a coastal shallow embayment in Central Chile with multiple uses, one of which is receiving wastewater from
industrial fisheries, steel mill effluents, and domestic sewage. A simulation model was developed and applied to dissolved
oxygen consumption by organic residues released into this embayment. Three compartments were established as function of: depth,
circulation and outfall location. The model compartments had different volumes, and their oxygen saturation value was used
as baseline. The parameters: (a) BOD5 of the industrial and urban effluents, (b) oxygen demand by organic sediments, (c) respiration, (d) photosynthesis and (e)
re-aeration were included in the model. Iteration results of the model showed severe alterations in Compartment 1, with a
decrease of 65% in the oxygen below saturation. Compartment 2 showed a small decline (10%) and compartment 3 did not show
apparent changes in oxygen values. Measures recommended for remediation were to decrease the BOD5 loading by 30% in the affected sector. Iteration of the model for 200 h following recommendations derived from the preceding
results produced an increase in saturation of 60% (5 ml O2 L−1), which suggested an improvement of the environmental conditions. 相似文献
3.
Methodological Basis of Ecological Safety Standards for the Technogenic Impact of Mineral Resource Exploitation 总被引:1,自引:0,他引:1
A new methodological approach to the development of biological and technological safety standards for the impact of underground mining on the natural biota is proposed. 相似文献
4.
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
5.
野生灵长类资源的旅游开发与保护关系探讨 总被引:5,自引:0,他引:5
以安徽黄山旅游开发利用野生短尾猴资源实践为基础,探讨了旅游开发与保护的辩证关系,提出了灵长类动物旅游开发中应注意的问题和采取的措施。 相似文献
6.
传统的海洋开发战略在导向上存在离散的缺憾与集成的缺失,造成了海洋开发的外部不经济和整体绩效不高.弥补传统海洋开发战略带来的危机,必然要求海洋开发战略创新,在国家层面上作出海洋开发战略整合的科学选择. 相似文献
7.
湿式脱硫除尘技术在开发应用中的几点看法 总被引:1,自引:0,他引:1
当前,随着经济的快速发展,全国燃煤量不断增加,二氧化硫、烟尘超标排放已导致严重的环境污染问题.二氧化硫、烟尘排放量的控制,可采用选用清洁煤,改变燃烧技术及末尾脱硫除尘技术.比较而言,烟气除尘脱硫技术是一种技术成熟较为经济的应用技术.其中湿式脱硫除尘技术已得到广泛推广与应用,但该技术中仍存在不能消除黑烟、二氧化硫脱除不稳定因素多、设备腐蚀问题.本文通过对实际测试结果分析及脱硫效率影响因素的分析,提出了相应的看法与建议. 相似文献
8.
西江沿岸地带是一个工业不发达的待开发民族区域,但它拥有多方面工业资源优势,而且工业开发环境条件良好。作者认为,优势的工业资源开发必须在全方位开放与资源深度利用的基础上以轻型为主导的策略,重点建设制糖、水果加工、水电、有色金属为主的原材料及加工等若干工业基地。布局上以西江干流和区内铁路干线为“轴”,结合重点工业“点”,稳定提高中部,重点开发东部,创造条件开发西部,实现“点轴结合,逐步推进”的工业资源区域开发策略。 相似文献
9.
河南省黄河湿地生态旅游资源的开发与保护研究 总被引:1,自引:0,他引:1
河南黄河湿地旅游资源丰富,有各具特色的湿地景观、复杂多样的生物景观、丰富的地文景观、悠久的历史人文景观和工程园林景观等多种景观类型;但目前存在着开发利用程度较低,市场营销不够、景点开发质量不高,旅游设备简陋、基础设施落后,景点少、点热面冷,人才缺乏、经营管理水平低等众多问题;最后从旅游功能分区、旅游开发、旅游管理、旅游线路设计、旅游环境监测、区域旅游联合、加大宣传力度等方面提出了河南黄河湿地生态旅游资源开发的对策. 相似文献
10.
油气田开发与炼化企业硫化氢危害分析与预防 总被引:2,自引:0,他引:2
分析了油田开发和炼油化工生产过程中H2S的分布区域、特点及危害.通过对66起H2S中毒事故的分析,指出在设备及管线的吹扫、堵漏、拆卸、安装作业过程中较易发生H2S中毒事故;事故主要是由于违章及误操作以及对H2S的毒害认识不够、安全意识差引起的.从管理措施、技术支持、人员培训、应急救援等方面提出了预防H2S中毒的措施. 相似文献