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排序方式: 共有616条查询结果,搜索用时 140 毫秒
611.
Michael J. Roast Samir Martins Lourdes Fernández-Peralta José Carlos Báez Ahmed Diame David March Jazel Ouled-Cheikh Adolfo Marco Jacob González-Solís Luis Cardona 《Conservation biology》2023,37(5):e14110
Fisheries bycatch is a critical threat to sea turtle populations worldwide, particularly because turtles are vulnerable to multiple gear types. The Canary Current is an intensely fished region, yet there has been no demographic assessment integrating bycatch and population management information of the globally significant Cabo Verde loggerhead turtle (Caretta caretta) population. Using Boa Vista island (Eastern Cabo Verde) subpopulation data from capture–recapture and nest monitoring (2013–2019), we evaluated population viability and estimated regional bycatch rates (2016–2020) in longline, trawl, purse-seine, and artisanal fisheries. We further evaluated current nesting trends in the context of bycatch estimates, existing hatchery conservation measures, and environmental (net primary productivity) variability in turtle foraging grounds. We projected that current bycatch mortality rates would lead to the near extinction of the Boa Vista subpopulation. Bycatch reduction in longline fisheries and all fisheries combined would increase finite population growth rate by 1.76% and 1.95%, respectively. Hatchery conservation increased hatchling production and reduced extinction risk, but alone it could not achieve population growth. Short-term increases in nest counts (2013–2021), putatively driven by temporary increases in net primary productivity, may be masking ongoing long-term population declines. When fecundity was linked to net primary productivity, our hindcast models simultaneously predicted these opposing long-term and short-term trends. Consequently, our results showed conservation management must diversify from land-based management. The masking effect we found has broad-reaching implications for monitoring sea turtle populations worldwide, demonstrating the importance of directly estimating adult survival and that nest counts might inadequately reflect underlying population trends. 相似文献
612.
613.
《油气田环境保护》2014,(2):68-70
This article classifies the atmospheric pollution sources according to the distribution of time, space and production conditions and summarizes the characteristics and hazards of all kinds of pollution sources. Through the analysis of environment impacts caused by pollu- tants, prevention measures for air pollutionin different stages of oil- field development are proposed, in an effort to control regional atmos- pheric environmental quality. 相似文献
614.
Louise Anderson Peter Houk Mark G. R. Miller Javier Cuetos-Bueno Curtis Graham Kriskitina Kanemoto Elizabeth Terk Elizabeth McLeod Maria Beger 《Conservation biology》2022,36(3):e13866
Localized stressors compound the ongoing climate-driven decline of coral reefs, requiring natural resource managers to work with rapidly shifting paradigms. Trait-based adaptive management (TBAM) is a new framework to help address changing conditions by choosing and implementing management actions specific to species groups that share key traits, vulnerabilities, and management responses. In TBAM maintenance of functioning ecosystems is balanced with provisioning for human subsistence and livelihoods. We first identified trait-based groups of food fish in a Pacific coral reef with hierarchical clustering. Positing that trait-based groups performing comparable functions respond similarly to both stressors and management actions, we ascertained biophysical and socioeconomic drivers of trait-group biomass and evaluated their vulnerabilities with generalized additive models. Clustering identified 7 trait groups from 131 species. Groups responded to different drivers and displayed divergent vulnerabilities; human activities emerged as important predictors of community structuring. Biomass of small, solitary reef-associated species increased with distance from key fishing ports, and large, solitary piscivores exhibited a decline in biomass with distance from a port. Group biomass also varied in response to different habitat types, the presence or absence of reported dynamite fishing activity, and exposure to wave energy. The differential vulnerabilities of trait groups revealed how the community structure of food fishes is driven by different aspects of resource use and habitat. This inherent variability in the responses of trait-based groups presents opportunities to apply selective TBAM strategies for complex, multispecies fisheries. This approach can be widely adjusted to suit local contexts and priorities. 相似文献
615.
Nick Hahlbeck William R. Tinniswood Matthew R. Sloat Jordan D. Ortega Matthew A. Wyatt Mark E. Hereford Ben S. Ramirez David A. Crook Kara J. Anlauf-Dunn Jonathan B. Armstrong 《Conservation biology》2022,36(3):e13857
A central tenet of landscape ecology is that mobile species depend on complementary habitats, which are insufficient in isolation, but combine to support animals through the full annual cycle. However, incorporating the dynamic needs of mobile species into conservation strategies remains a challenge, particularly in the context of climate adaptation planning. For cold-water fishes, it is widely assumed that maximum temperatures are limiting and that summer data alone can predict refugia and population persistence. We tested these assumptions in populations of redband rainbow trout (Oncorhynchus mykiss newberrii) in an arid basin, where the dominance of hot, hyperproductive water in summer emulates threats of climate change predicted for cold-water fish in other basins. We used telemetry to reveal seasonal patterns of movement and habitat use. Then, we compared contributions of hot and cool water to growth with empirical indicators of diet and condition (gut contents, weight–length ratios, electric phase angle, and stable isotope signatures) and a bioenergetics model. During summer, trout occurred only in cool tributaries or springs (<20 °C) and avoided Upper Klamath Lake (>25 °C). During spring and fall, ≥65% of trout migrated to the lake (5–50 km) to forage. Spring and fall growth (mean [SD] 0.58% per day [0.80%] and 0.34 per day [0.55%], respectively) compensated for a net loss of energy in cool summer refuges (–0.56% per day [0.55%]). In winter, ≥90% of trout returned to tributaries (25–150 km) to spawn. Thus, although perennially cool tributaries supported thermal refuge and spawning, foraging opportunities in the seasonally hot lake ultimately fueled these behaviors. Current approaches to climate adaptation would prioritize the tributaries for conservation but would devalue critical foraging habitat because the lake is unsuitable and unoccupied during summer. Our results empirically demonstrate that warm water can fuel cold-water fisheries and challenge the common practice of identifying refugia based only on summer conditions. 相似文献
616.
三塘湖油田生态环境保护指导思想为:"分区保护、分类防治、分级管理"。文章通过分析干旱荒漠区生态功能的划分,根据三塘湖油田开发区生态环境特征、生态系统服务功能、生态环境功能重要性与敏感性的空间分异规律,确定区域生态功能分区,为制定生态环境保护计划、维护区域生态安全、促进社会经济可持续发展提供科学依据。 相似文献