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1.
The designation of no‐take marine reserves involves social and economic concerns due to the resulting displacement of fishing effort, when fishing rights are removed from those who traditionally fished within an area. Displacement can influence the functioning of the fishery and success of the reserve, yet levels of displacement are seldom quantified after reserve implementation and very rarely before that. We devised a simple analytical framework based on set theory to facilitate reserve placement. Implementation of the framework requires maps of fishing grounds, fishing effort, or catch per unit effort for at least 2 years. The framework quantifies the level of conflict that a reserve designation might cause in the fishing sector due to displacement and the opportunities to offset the conflict through fisher spatial mobility (i.e., ability of fishers to fish elsewhere). We also considered how the outputs of the framework can be used to identify targeted management interventions for each fishery. We applied the method in Honduras, where the largest marine protected area in Central America is being placed, for which spatial data on fishing effort were available for 6 fisheries over 3 years. The proposed closure had a greater negative impact on the shrimp and lobster scuba fisheries, which concentrated respectively 28% and 18% of their effort inside the reserve. These fisheries could not accommodate the displacement within existing fishing grounds. Both would be forced to stretch into new fishing grounds, which are available but are of unknown quality. These stakeholders will likely require compensation to offset costly exploratory fishing or to travel to fishing grounds farther away from port. 相似文献
2.
Landowners can intentionally impair biodiversity values occurring on their land to pre-empt biodiversity protection. This often leads to significant negative effects on biodiversity. We studied whether landowners in Finland engaged in pre-emptive loggings after they were notified that their wooded mires are candidate sites for a mire protection program. After the notification, harvesting rates of the candidate wooded mires were significantly lower compared to harvesting rates of similar but non-candidate wooded mires. Annual and monthly harvesting rates indicated that notifying landowners of the conservation potential did not launch systematic pre-emptive logging behavior. Nevertheless, part of the candidate wooded mires were logged, so some landowners place more weight on other values than the biodiversity ones. Pre-emptive behavior has been observed in other studies suggesting that many country- or system-specific factors such as cultural background or level of compensation can affect landowners’ behavior.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01354-4) contains supplementary material, which is available to authorized users. 相似文献
3.
湖北省珍稀濒危保护水禽物种多样性及种群数量 总被引：3，自引：0，他引：3
使用直接计数法和专项调查法于1996年5月～2003年7月对湖北省珍稀濒危保护水禽物种多样性和种群数量进行了研究。结果表明：湖北省珍稀濒危保护水禽有45种,隶属于6目9科24属;记录到34种,其中有黄嘴白鹭和小苇鳽2个新记录种。按区系型分,古北界种类占优势,有35种,东洋种8种,广布种2种;按季节型分,冬候鸟为主体,有30种,夏候鸟8种,旅鸟5种,留鸟2种;按生活型分,涉禽23种,游禽22种,种类几乎相等。种群数量为41.1796万只。在45种珍稀水禽中,IUC红皮书水禽23种,8 247只;中国红皮书水禽22种,3 615只;CITES濒危水禽23种,40.631 6万只;国家重点保护水禽24种,3 838只。角等11种水禽未发现,可能已绝迹或极度濒危。按水禽1 %地理种群数量的标准,洪湖、沉湖、龙感湖、梁子湖、网湖等湿地可以确定为国际重要湿地。 相似文献
4.
天目山国家级保护区加入世界生物圈保护区网络已经10年,为了更好地保护其生物多样性和文化多样性,并可持续地利用好该保护区的自然资源,需适应客观形势发展的要求,把天目山国家级保护区建成为名副其实的生物圈保护区。采用现场实地考察、社区居民访谈、保护区管理者和政府人员座谈、历史资料查询等方法,了解到天目山保护区在自然资源保护、科研监测、教育培训、资源持续利用和生态旅游等方面取得了不少的成绩,但也存在诸如保护区面积尚欠不够、毛竹林资源能否合理利用和柳杉林的衰亡与病虫害的防治等问题。按照生物圈保护区的管理理念并参照以上的调查和思考,提出下列3条建议：一是扩大保护区的面积,二是建立一个完善的保护区共管机制,三是建立学术顾问委员会协助推动保护区各方面的工作。 相似文献
5.
黄土塬面是黄土高原地区主要的农业分布区和人口聚居地,地位十分重要。黄土塬面潜在蒸发量(ET0)的研究对于区域水循环研究、水土流失防治及农业的可持续发展具有重要意义。基于黄土塬面保护区1960—2017年的气象数据,利用Penman-Monteith模型、小波分析、Mann-Kendall非参数检验等方法研究了黄土塬面保护区ET0的变化规律及其与气象、环流因子间的关系。结果表明:(1)黄土塬面保护区多年平均ET0为1173.4 mm,总体呈现增长趋势,增长率为21.1 mm/10 a;其生长季平均ET0值及增长率均高于非生长季平均ET0。(2)该区多年平均ET0空间分布特征表现为东部高西部低,西部甘肃塬区多年平均ET0远低于东部山西塬区。(3)过去58年来,区域年均、生长季、非生长季ET0均呈现出增长趋势,但空间差异明显;研究区年均ET0存在着10年、30年和50年的震荡周期,其中以30年周期... 相似文献
6.
在国家公园体制改革背景下,“建立以国家公园为主体的自然保护地体系”对我国自然保护地优化整合提出了系列要求。福建省正在进行自然保护地优化整合,泰宁县是全省自然保护地交叉重叠最复杂的区域之一。以泰宁县为例,基于实地调研和专家意见,构建了三个优化整合的情景规划方案：（1）维持现状,不整合;（2）以泰宁国家地质公园为主体的整合;（3）以泰宁国家公园为主体的整合。基于对方案的成本效益比较,结果显示：方案3的存在和使用价值最高,成本持中;方案1的价值保护持中,成本最低;方案2价值最低,成本最高。研究为福建省县市尺度开展自然保护地优化整合提供思路和技术支持,亦为国内外自然保护地的边界优化提供参考。 相似文献
7.
ＩｎｔｒｏｄｕｃｔｉｏｎＷｅｔｌａｎｄｉｓｏｎｅｏｆｔｈｅｒｉｃｈｅｓｔｂｉｏｄｉｖｅｒｓｉｔｙａｒｅａｓｉｎｔｈｅｅａｒｔｈ .Ｂｉｏｄｉｖｅｒｓｉｔｙｓｈｏｕｌｄｉｎｃｌｕｄｅｆｏｕｒｌｅｖｅｌｓ:ｈｅｒｅｄｉｔｙｄｉｖｅｒｓｉｔｙ ,ｓｐｅｃｉｅｓｄｉｖｅｒｓｉｔｙ ,ｅｃｏｓｙｓｔｅｍｄｉｖｅｒｓｉｔｙａｎｄｌａｎｄｓｃａｐｅｄｉｖｅｒｓｉｔｙ .Ｓｐｅａｋｉｎｇｆｒｏｍｃｅｒｔａｉｎａｎｇｌｅｓ,ｔｈｅｐｒｏｔｅｃｔｉｏｎｏｆｅｃｏｓｙｓｔｅｍｄｉｖｅｒｓｉｔｙａｎｄｌａｎｄｓｃａｐｅｄｉｖｅｒ… 相似文献
8.
Island species are difficult to conserve because they face the synergy of climate change, invasive species, deforestation, and increasing human population densities in areas where land mass is shrinking. The Caribbean island of Hispaniola presents particular challenges because of geopolitical complexities that span 2 countries and hinder coordinated management of species across the island. We employed species distribution modeling to evaluate the impacts of climatic change and anthropogenic activities on the distribution of an endemic mammal of conservation concern, the Hispaniolan solenodon (Solenodon paradoxus). We aggregated occurrence points for this poorly known species for the Last Glacial Maximum (LGM) and the present (1975–2016) based on museum collections, online biodiversity databases, and new field surveys. We quantified degree of overlap between periods and scenarios with Schoener's D. Through a conservation paleobiology lens, we found that over time humans played an increasing role in shaping the distribution of S. paradoxus, thus, providing a foundation for developing conservation strategies on appropriate spatiotemporal scales. Human population density was the single most important predictor of S. paradoxus occurrence. Densities >166 people/km2 corresponded to a near-zero probability of occurrence. Models that accounted for climate but not anthropogenic variables falsely identified suitable habitat in Haiti, where on-the-ground surveys confirm habitat is unavailable. Climate-only models also significantly overestimated the potential for habitat connectivity between isolated populations. Our work highlights that alternative fates for S. paradoxus in the Anthropocene exist across the political border between the Dominican Republic and Haiti due to the fundamentally different economic and political realities of each country. Relationships in the fossil record confirm that Hispaniola's sociopolitical boundary is not biologically significant but instead represents one imposed on the island's fauna in the past 500 years by colonial activity. Our approach reveals how a paleontological perspective can contribute to concrete management insights. 相似文献
9.
Indigenous Uses, Population Density, and Conservation of Threatened Medicinal Plants in Protected Areas of the Indian Himalayas 总被引：3，自引：0，他引：3
CHANDRA PRAKASH KALA† 《Conservation biology》2005,19(2):368-378
Abstract: For 10 years I monitored the population density of threatened medicinal plant species in seven protected areas in the Indian Himalayas. I also documented the indigenous uses of threatened medicinal plants through interviews with 138 herbal healers (83 Tibetan healers and 55 Ayurvedic healers) residing in the buffer zone villages of these protected areas. To assess the population status of threatened medicinal plant species, I sampled the 10 major habitat types in the protected areas. In all, I found 60 threatened medicinal plant species during the study period, of which 54 species occurred in the sampling plots. Twenty-two percent of threatened medicinal plant species were critically endangered, 16% were endangered, and 27% were vulnerable. Thirty-two threatened medicinal plant species were endemic to the Himalayan region. The density of threatened medicinal plant species varied with protected areas. The Valley of Flowers protected area had the highest number of threatened medicinal plant species. The "moist" habitat type was richest in these species among all 10 habitat types sampled. Arnebia euchroma (Royle ex Benth.) Johnston and Ephedra gerardiana Wall. ex Stapf. were the most common threatened medicinal plant species. The indigenous groups of healers used these threatened species in curing about 45 different ailments. Based on my findings, I believe that to ensure the long-term sustainability of threatened medicinal plants, medicinal-plant conservation areas should be established. 相似文献
10.
王献溥 《生态与农村环境学报》1993,(1)
当前,世界130个国家已建立了6500多个保护区,约占地球土地面积4.89％。但是,如何管理好它们,还存在许多问题。本文重点介绍这些问题,并提出一些解决措施,以促进保护区事业的发展。 相似文献