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71.
Fishing industry and related perspectives on the issues raised by no-take marine protected area proposals 总被引:2,自引:2,他引:0
In the face of growing calls for no-take marine protected areas (NTMPAs), the views of fishing industry representatives in south-west (SW) England on related issues are analysed. Only 23% thought NTMPAs were the way forward and a range of concerns were expressed, e.g. that the ‘terrestrial’ protected areas approach and related biodiversity conservation objectives will be extended to the seas, and that fish yield reductions from the loss of access to NTMPAs are very unlikely to be compensated for through spillover/export. Some interesting approaches to ameliorating these concerns emerged, such as being open and honest that NTMPAs are primarily intended to achieve biodiversity conservation benefits, reducing uncertainty concerning the potential for any secondary fisheries spillover/export benefits, justifying NTMPAs on an objective, rational basis rather than on a subjective, precautionary basis, and the quid pro quo streamlining of wider fisheries management approaches. This research reveals a more diverse range of perspectives amongst fishing industry representatives on the issues raised by NTMPA proposals than is often assumed. 相似文献
72.
73.
2004年春季东海赤潮高发区COD分布及其与赤潮关系的初步研究 总被引:6,自引:0,他引:6
2004年4~5月初在东海赤潮高发区暴发的特大规模原甲藻赤潮前期和暴发初期对该海域进行的现场调查,并对该海域COD的分布特征进行了探讨。结果表明,赤潮暴发前COD为0.295-1.836mg/L,主要受陆源输入影响。根据其在局部海区底层出现的异常升高结合其他参数分析可对特定海区潜在赤潮暴发的可能性进行评估。赤潮暴发时COD为0.36~3.14mg/L,表层和中层与叶绿素存在显著正相关关系,表明其主要受生物影响。富营养化指数表明赤潮暴发前近一半海域已经处于富营养化状态,但COD对富营养化的贡献不如营养盐重要。 相似文献
74.
在海洋经济质量转型之期,基于“认知—评价—建构—优化”理念,界定海洋经济增长质量内涵,通过中心-引力模型评价分析2000—2014年辽宁沿海地区海洋经济增长质量空间特征,构建了海洋经济增长质量模型,识别影响其空间特征的相关要素,并根据要素作用程度提出优化建议。研究发现:① 辽宁沿海地区海洋经济增长质量呈“核心—圈层”结构,形成以大连为“领头雁”的雁阵式相互继起模式;“钻石型”引力流结构促成辽宁沿海地区集中化连片发展格局;② 海洋经济增长质量空间特征主要受空间集聚效应影响,海洋资本、海洋基建和海洋产业结构成为推动海洋经济增长质量循环引力流的顺流机制,其中海洋产业结构成为影响辽宁海洋经济增长质量圈层空间集聚效应的关键流;海洋人才成为制约海洋经济增长质量循环引力流的逆流机制;③ 通过路径作用程度的象限划分,提出强化大连中心地职能,针对腹地城市定位及资源禀赋条件提出调控措施,推进沿海区域协调与一体化进程。 相似文献
75.
Journal of Geographical Sciences - This paper investigated spatial structures of 3418 national protected areas (NPAs) grouped into 13 types using GIS and quantitative analysis, including point... 相似文献
76.
ABSTRACTIn the past, population growth in Australia's Northern Territory, as in other peripheral parts of high-income countries, has been driven by internal labour migration and migration from outside of Australia. These have been contributing to the high population turnover experienced in peripheral areas. Since 2010, the Northern Territory has experienced low (and even negative) population growth, and public policy is currently focused on migration as a lever to reverse this trend. However, the extent to which the characteristics of migrants influence the potential for longer-term population growth is poorly understood. This paper uses a new method to analyse the contributions of various types of migrants to both population turnover and retention. Two major sets of findings emerge: First, the significance of separating newer in-migrants from longer-term residents when analysing migration patterns; and secondly, the contribution of age, gender, Indigenous status, international origin, wages and industry of employment to the Northern Territory's population turnover. The research suggests that current forms of migration favour people who are likely to stay for only short periods, and have high wage demands. The main policy inference is that long-term population growth will likely not eventuate unless new forms of migration can be stimulated. 相似文献
77.
Joe Weber 《The Professional geographer》2019,71(2):239-252
In the twenty-first century, there are three American Wests, which cut across cultural, political, physical, and economic boundaries. Parts of the West are booming, building homes, and adding population; others are legally off limits to such development; and much of the West has been bypassed by such development and growth. These are called here the Booming West, Protected West, and Bypassed West. Maps of climate, political boundaries, ethnic and racial identities, or presidential voting patterns do not match these three Wests. Each West has a different relationship to the others and might see them as threats or opportunities, and each West can be expected to grow in different areas at the expense of other Wests. The boundaries between the three Wests could be important locations; sharp transitions can exist between Wests, perhaps nowhere more so than where a fast growing metro area abuts a national park or forest boundary. Finally, the effects of climate change cut across the three Wests and have different implications for their future. Continued population growth will further emphasize the boundaries between each of the three Wests and raise the stakes for their control. 相似文献
78.
Nitin D. Rai Tor A. Benjaminsen Siddhartha Krishnan C. Madegowda 《Singapore journal of tropical geography》2019,40(1):124-139
Protected areas have had significant impacts on local communities primarily through the physical removal of people. In some instances, people continue to live within protected areas due to the inability of the state to evict them. The restrictions on livelihoods placed on people living inside protected areas lead to in situ displacement. We show how conservation enclosures in the Biligiri Rangaswamy Temple Tiger Reserve have produced a class of people that the state ‘lets die’ by banning customary practices such as fire use, hunting and harvesting of forest produce. Using longitudinal ethnographic, socio‐economic and ecological data, we demonstrate that conservation policy has alienated indigenous forest dwellers from their agricultural and forest‐land. The outcomes of conservation policy include dispossession through increased crop losses, reduced income from agriculture and forest produce, as well as a forest that is dominated by weeds due to fire suppression. The ban on hunting in particular has increased wildlife densities, which has enabled the state to accumulate revenues through the establishment of wildlife tourism facilities. All in all, centralized protected area governance has changed the relationships among people, forest and the state in a way that has produced adverse effects for both livelihoods and the ecosystem. 相似文献
79.
西北贫困地区乡村类型识别与振兴途径研究 总被引:13,自引:2,他引:11
乡村振兴战略是新时期我国推进城乡融合发展的重要举措。贫困地区既是脱贫攻坚的主战场,又是乡村振兴的重点区域。如何科学识别村落类型,分类推进典型区域乡村振兴发展,对于破解农村发展不平衡不充分问题具有重要的现实意义。本文解析了乡村地域系统发展理论,阐释了城乡融合发展理论,剖析了村域空间结构格局演变和城乡要素结构功能优化重组;构建了西北干旱贫困地区乡村振兴村落类型识别体系,从乡村主体、产业发展、人居环境、资源禀赋4个子系统进行逐级分类判断,识别乡村主导类型,结合专家征询分析与村落特征,将乡村振兴村落类型识别为集聚提升类、三产融合类、城郊融合类、特色保护类、搬迁撤并类,结合不同乡村振兴模式提出了相应地发展路径,以期为乡村振兴提供理论依据与决策参考。 相似文献
80.
OA Bergstad ÅS Høines R Sarralde G Campanis M Gil F Ramil 《African Journal of Marine Science》2019,41(1):11-28
Most of the Southeast Atlantic Ocean is abyssal, and global bathymetries suggest that only ~3.2% of the areas beyond national jurisdiction (ABNJ; also known as the high seas, as defined in the United Nations Convention on the Law of the Sea [UNCLOS]) are shallower than 2 500 m. This study mapped bathymetry and characterised substrates in selected seamount summit areas, including several that have been or may become fishing areas. The southernmost location, the Schmitt-Ott Seamount, has exposed volcanic bedrock with surrounding flats covered by thin biogenic sediments and/or coral rubble that appears ancient. At Wüst, Vema, Valdivia and Ewing seamounts the basaltic base appears to be overlain by coral caps and other coral substrates (sheets, rubble). Adjacent summit plains have biogenic sediments of varying thickness. Vema has a flat, roughly circular summit, <100 m deep, with the shallowest point being a 22-m-deep summit knoll; the upper slopes have ancient coral framework, but the summit has a mixture of coralline and volcanic rock and coarse sediments, including extensive areas with coralline algae and kelp forests. Valdivia Bank is a 230-m-deep, flat, rocky area (~11 × 5 km), protruding steeply from the extensive multi-summit Valdivia subarea of the Walvis Ridge. The distribution of past fisheries in the Convention Area of the South East Atlantic Fisheries Organisation (SEAFO) was considered in relation to the new information on bathymetry and substrate. 相似文献