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81.
Phoebe J. Stewart-Sinclair Carissa J. Klein Ian J. Bateman Catherine E. Lovelock 《Conservation biology》2021,35(6):1850-1860
Marine coastal ecosystems, commonly referred to as blue ecosystems, provide valuable services to society but are under increasing threat worldwide due to a variety of drivers, including eutrophication, development, land-use change, land reclamation, and climate change. Ecological restoration is sometimes necessary to facilitate recovery in coastal ecosystems. Blue restoration (i.e., in marine coastal systems) is a developing field, and projects to date have been small scale and expensive, leading to the perception that restoration may not be economically viable. We conducted a global cost–benefit analysis to determine the net benefits of restoring coral reef, mangrove, saltmarsh, and seagrass ecosystems, where the benefit is defined as the monetary value of ecosystem services. We estimated costs from published restoration case studies and used an adjusted-value-transfer method to assign benefit values to these case studies. Benefit values were estimated as the monetary value provided by ecosystem services of the restored habitats. Benefits outweighed costs (i.e., there were positive net benefits) for restoration of all blue ecosystems. Mean benefit:cost ratios for ecosystem restoration were eight to 10 times higher than prior studies of coral reef and seagrass restoration, most likely due to the more recent lower cost estimates we used. Among ecosystems, saltmarsh had the greatest net benefits followed by mangrove; coral reef and seagrass ecosystems had lower net benefits. In general, restoration in nations with middle incomes had higher (eight times higher in coral reefs and 40 times higher in mangroves) net benefits than those with high incomes. Within an ecosystem type, net benefit varied with restoration technique (coral reef and saltmarsh), ecosystem service produced (mangrove and saltmarsh), and project duration (seagrass). These results challenge the perceptions of the low economic viability of blue restoration and should encourage further targeted investment in this field. 相似文献
82.
Amanda Xuereb Cassidy C. D'Aloia Marco Andrello Louis Bernatchez Marie-Josée Fortin 《Conservation biology》2021,35(3):909-920
The availability of genomic data for an increasing number of species makes it possible to incorporate evolutionary processes into conservation plans. Recent studies show how genetic data can inform spatial conservation prioritization (SCP), but they focus on metrics of diversity and distinctness derived primarily from neutral genetic data sets. Identifying adaptive genetic markers can provide important information regarding the capacity for populations to adapt to environmental change. Yet, the effect of including metrics based on adaptive genomic data into SCP in comparison to more widely used neutral genetic metrics has not been explored. We used existing genomic data on a commercially exploited species, the giant California sea cucumber (Parastichopus californicus), to perform SCP for the coastal region of British Columbia (BC), Canada. Using a RAD-seq data set for 717 P. californicus individuals across 24 sampling locations, we identified putatively adaptive (i.e., candidate) single nucleotide polymorphisms (SNPs) based on genotype–environment associations with seafloor temperature. We calculated various metrics for both neutral and candidate SNPs and compared SCP outcomes with independent metrics and combinations of metrics. Priority areas varied depending on whether neutral or candidate SNPs were used and on the specific metric used. For example, targeting sites with a high frequency of warm-temperature-associated alleles to support persistence under future warming prioritized areas in the southern coastal region. In contrast, targeting sites with high expected heterozygosity at candidate loci to support persistence under future environmental uncertainty prioritized areas in the north. When combining metrics, all scenarios generated intermediate solutions, protecting sites that span latitudinal and thermal gradients. Our results demonstrate that distinguishing between neutral and adaptive markers can affect conservation solutions and emphasize the importance of defining objectives when choosing among various genomic metrics for SCP. 相似文献
83.
Impact of conservation areas on trophic interactions between apex predators and herbivores on coral reefs
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Apex predators are declining at alarming rates due to exploitation by humans, but we have yet to fully discern the impacts of apex predator loss on ecosystem function. In a management context, it is critically important to clarify the role apex predators play in structuring populations of lower trophic levels. Thus, we examined the top‐down influence of reef sharks (an apex predator on coral reefs) and mesopredators on large‐bodied herbivores. We measured the abundance, size structure, and biomass of apex predators, mesopredators, and herbivores across fished, no‐take, and no‐entry management zones in the Great Barrier Reef Marine Park, Australia. Shark abundance and mesopredator size and biomass were higher in no‐entry zones than in fished and no‐take zones, which indicates the viability of strictly enforced human exclusion areas as tools for the conservation of predator communities. Changes in predator populations due to protection in no‐entry zones did not have a discernible influence on the density, size, or biomass of different functional groups of herbivorous fishes. The lack of a relationship between predators and herbivores suggests that top‐down forces may not play a strong role in regulating large‐bodied herbivorous coral reef fish populations. Given this inconsistency with traditional ecological theories of trophic cascades, trophic structures on coral reefs may need to be reassessed to enable the establishment of appropriate and effective management regimes. El Impacto de las Áreas de Conservación sobre las Interacciones Tróficas entre los Depredadores Dominantes y los Herbívoros en los Arrecifes de Coral 相似文献
84.
Shifting elasmobranch community assemblage at Cocos Island—an isolated marine protected area
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Easton R. White Mark C. Myers Joanna Mills Flemming Julia K. Baum 《Conservation biology》2015,29(4):1186-1197
Fishing pressure has increased the extinction risk of many elasmobranch (shark and ray) species. Although many countries have established no‐take marine reserves, a paucity of monitoring data means it is still unclear if reserves are effectively protecting these species. We examined data collected by a small group of divers over the past 21 years at one of the world's oldest marine protected areas (MPAs), Cocos Island National Park, Costa Rica. We used mixed effects models to determine trends in relative abundance, or probability of occurrence, of 12 monitored elasmobranch species while accounting for variation among observers and from abiotic factors. Eight of 12 species declined significantly over the past 2 decades. We documented decreases in relative abundance for 6 species, including the iconic scalloped hammerhead shark (Sphyrna lewini) (?45%), whitetip reef shark (Triaenodon obesus) (?77%), mobula ray (Mobula spp.) (?78%), and manta ray (Manta birostris) (?89%), and decreases in the probability of occurrence for 2 other species. Several of these species have small home ranges and should be better protected by an MPA, which underscores the notion that declines of marine megafauna will continue unabated in MPAs unless there is adequate enforcement effort to control fishing. In addition, probability of occurrence at Cocos Island of tiger (Galeocerdo cuvier), Galapagos (Carcharhinus galapagensis), blacktip (Carcharhinus limbatus), and whale (Rhincodon typus) sharks increased significantly. The effectiveness of MPAs cannot be evaluated by examining single species because population responses can vary depending on life history traits and vulnerability to fishing pressure. 相似文献
85.
Emerging conservation challenges and prospects in an era of offshore hydrocarbon exploration and exploitation
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Globally, extensive marine areas important for biodiversity conservation and ecosystem functioning are undergoing exploration and extraction of oil and natural gas resources. Such operations are expanding to previously inaccessible deep waters and other frontier regions, while conservation‐related legislation and planning is often lacking. Conservation challenges arising from offshore hydrocarbon development are wide‐ranging. These challenges include threats to ecosystems and marine species from oil spills, negative impacts on native biodiversity from invasive species colonizing drilling infrastructure, and increased political conflicts that can delay conservation actions. With mounting offshore operations, conservationists need to urgently consider some possible opportunities that could be leveraged for conservation. Leveraging options, as part of multi‐billion dollar marine hydrocarbon operations, include the use of facilities and costly equipment of the deep and ultra‐deep hydrocarbon industry for deep‐sea conservation research and monitoring and establishing new conservation research, practice, and monitoring funds and environmental offsetting schemes. The conservation community, including conservation scientists, should become more involved in the earliest planning and exploration phases and remain involved throughout the operations so as to influence decision making and promote continuous monitoring of biodiversity and ecosystems. A prompt response by conservation professionals to offshore oil and gas developments can mitigate impacts of future decisions and actions of the industry and governments. New environmental decision support tools can be used to explicitly incorporate the impacts of hydrocarbon operations on biodiversity into marine spatial and conservation plans and thus allow for optimum trade‐offs among multiple objectives, costs, and risks. 相似文献
86.
为了揭示出海洋纤毛虫在人工海水中及不同温度下的种群动力学,利用实验生态学方法,就4种培养液及2种(17℃和23℃)温度对海洋纤毛虫扇形游仆虫(Euplotesvannus Müller,1786)种群增长的影响进行了初步探讨.结果显示①该种纤毛虫原生动物在4种人工海水培养液中的种群增长率大小顺序为牛肉浸膏培养液>米粒培养液>酵母粉培养液>蛋白胨培养液;②种群密度大小顺序依次为米粒培养液>牛肉浸膏培养液>酵母粉培养液>蛋白胨培养液;③指数增长期及稳定期在米粒培养液中均长于牛肉浸膏培养液;④随着培养温度的升高,种群增长率增大,指数增长期及稳定期缩短;⑤温度系数(Q10)的大小顺序为蛋白胨培养液>牛肉浸膏培养液>米粒培养液>酵母粉培养液.结果表明,米粒人工海水培养液不仅适合于保种培养,而且适合于种群的扩大培养,而牛肉浸膏培养液更适合于种群的快速扩大培养,其他两种培养液则只适合于保种培养.图2表4参13 相似文献
87.
在严格厌氧条件下,研究了驾琼盆地东方1-1-1井垂直剖面不同沉积层地质样品中的厌氧纤维素分解菌.结果表明:厌氧纤维素分解菌在各样品中都存在,但其分布有很大随机性,与样品埋藏深度无相关性,与样品中一些有机物含量,如纤维素、半纤维素也无相关性,厌氧纤维素分解菌数量高的样品,其在生物模拟产甲烷实验中的单位有机质产气量也较高,有显著的相关性.菌体形态主要为杆菌和球菌. 相似文献
88.
Avril Siung-Chang 《Environmental geochemistry and health》1997,19(2):45-55
Marine pollution and coastal degradation have become serious development issues in the Caribbean. Early evidence of marine pollution was mainly anecdotal, but within the last 10--15 years, work conducted by universities and research institutions in the Region has provided the beginnings of a database that identifies several common marine pollution problems. The United Nations Environment Programme (UNEP), the Intergovernmental Oceanographic Commission (IOC) and the Pan American World Health Organization (PAHO/WHO) have also been instrumental in co-ordinating several marine pollution studies. In the English-speaking Caribbean, the University of the West Indies, the Institute of Marine Affairs in Trinidad and Tobago, and the Caribbean Environmental Health Institute located in St Lucia, have taken a lead role in identifying marine pollution problems in their Sub-Region. For the Wider Caribbean a database for petroleum pollution and marine debris has been developed. Land-based sources of marine pollution have been identified as a major problem, with several hot spots identified in mainland countries and in some of the larger industrialised islands. Organic and nutrient pollution, particularly from sewage, is most widespread and is possibly the most serious marine pollution problem in the Caribbean. A lack of capital investment funds to install the appropriate infrastructure to deal with sewage and other liquid effluents is a major stumbling block to solving the problem of marine pollution in the Caribbean. Other factors include political will and administrative and legal structures to regulate human development activities. 相似文献
89.
西太平洋海域海水和雨水的化学特征 总被引:2,自引:0,他引:2
本工作测定了西太平洋海域中海水、海水悬浮物和海面上雨水的元素组成和浓度。通过富集因子的计算,探讨海面上雨水中微量元素的富集程度及其来源,讨论了海面上气溶胶粒子大小与洗出因子的关系,结果表明不同质量粒径大小的微量元素在公海上具有相似的洗出因子。 相似文献
90.
三种海藻凝集素细胞凝集活性的比较 总被引:3,自引:0,他引:3
比较了3种经纯化的海藻凝集素即铁钉菜凝集素(IOL),鹿角沙菜凝集素(HCL0和脆江蓠凝集素(GBL)对红细胞,微藻,细菌,酵母及肿瘤细胞的凝集活性,IOL对供试的动物红细胞均有凝集作用,而HCL和GBL只对部分红细胞产生凝集作用,3种凝集素都不能凝集人的A,O,B型血红细胞。在12种供试的微藻中,有6种单细胞藻类分别被海藻凝集素所凝集,海洋微藻比淡水微藻敏感,盐生杜氏藻均可被3种海藻凝集素所凝集,3种海藻凝集素都能凝集枯草杆菌,但不能凝集胃癌细胞,3种凝集素中,IOL对细胞的凝集作用最好,表3参13 相似文献