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371.
Correlations and cross-correlations between forest fires in the province of British Columbia, Canada, and sea surface temperatures in the Pacific Ocean were evaluated. British Columbia has a long Pacific Ocean coastline; given that there may be teleconnections between the province's forest fires and climate variability over the ocean, significant correlations may exist between forest fires and the sea surface temperature of the Pacific Ocean. Fire occurrences and areas burned through lightning-caused and human-caused fires were analyzed against individual 1° × 1° grid cells of anomalies in the sea surface temperature to determine correlations for the period 1950-2006. Significant correlations (p < 0.05) for vast areas of the ocean were found between occurrences of lightning-caused fires and sea surface temperature anomalies for time lags of 1 and 2 years, whereas significant correlations between occurrences of human-caused fires and sea surface temperature anomalies occurred extensively for many time lags. To support the results of this approach, correlations between fire data and the Niño 3.4, Pacific Decadal Oscillation, and Arctic Oscillation indices were tested for the same period. Significant correlations were found between fire occurrences and these indices at certain time lags. Overall, fire occurrence appeared to be more extensively correlated with sea surface temperature anomalies than was area burned. These results support the hypothesis that teleconnections exist between fire activity in British Columbia and sea surface temperatures in the Pacific Ocean, and the correlations suggest that linear regression models or other regression techniques may be appropriate for predicting fire severity from the sea surface temperatures of one or more previous years.  相似文献   
372.
The effect of anthropogenic landscape change on disease in wildlife populations represents a growing conservation and public health concern. Red colobus monkeys (Procolobus rufomitratus), an endangered primate species, are particularly susceptible to habitat alteration and have been the focus of a great deal of disease and ecological research as a result. To infer how landscape changes can affect host and parasite dynamics, a spatially explicit agent-based model is created to simulate movement and foraging of this primate, based on a resource landscape estimated from extensive plot-derived tree population data from Kibale National Park, Uganda. Changes to this resource landscape are used to simulate effects of anthropogenic forest change. With each change in the landscape, disease outcomes within the simulated red colobus population are monitored using a hypothetical microparasite with a directly transmitted life cycle. The model predicts an optimal distribution of resources which facilitates the spread of an infectious agent through the simulated population. The density of resource rich sites and the overall heterogeneity of the landscape are important factors contributing to this spread. The characteristics of this optimal distribution are similar to those of logged sections of forest adjacent to our study area.  相似文献   
373.
Management and Recovery Options for Ural River Beluga Sturgeon   总被引:1,自引:0,他引:1  
Abstract: Management of declining fisheries of anadromous species sometimes relies heavily on supplementation of populations with captive breeding, despite evidence that captive breeding can have negative consequences and may not address the root cause of decline. The beluga sturgeon (Huso huso), a species threatened by the market for black caviar and reductions in habitat quality, is managed through harvest control and hatchery supplementation, with an emphasis on the latter. We used yield per recruit and elasticity analyses to evaluate the population status and current levels of fishing and to identify the life‐history stages that are the best targets for conservation of beluga of the Ural River. Harvest rates in recent years were four to five times higher than rates that would sustain population abundance. Sustainable rates of fishing mortality are similar to those for other long‐lived marine species such as sharks and mammals. Yield per recruit, which is maximized if fish are first harvested at age 31 years, would be greatly enhanced by raising minimum size limits or reducing illegal take of subadults. Improving the survival of subadult and adult females would increase population productivity by 10 times that achieved by improving fecundity and survival from egg to age 1 year (i.e., hatchery supplementation). These results suggest that reducing mortality of subadults and adult wild fish is a more effective conservation strategy than hatchery supplementation. Because genetics is not factored into hatchery management practices, supplementation may even reduce the viability of the beluga sturgeon.  相似文献   
374.
Assessing species’ extinction risk is vital to setting conservation priorities. However, assessment endeavors, such as those used to produce the IUCN Red List of Threatened Species, have significant gaps in taxonomic coverage. Automated assessment (AA) methods are gaining popularity to fill these gaps. Choices made in developing, using, and reporting results of AA methods could hinder their successful adoption or lead to poor allocation of conservation resources. We explored how choice of data cleaning type and level, taxonomic group, training sample, and automation method affect performance of threat status predictions for plant species. We used occurrences from the Global Biodiversity Information Facility (GBIF) to generate assessments for species in 3 taxonomic groups based on 6 different occurrence-based AA methods. We measured each method's performance and coverage following increasingly stringent occurrence cleaning. Automatically cleaned data from GBIF performed comparably to occurrence records cleaned manually by experts. However, all types of data cleaning limited the coverage of AAs. Overall, machine-learning-based methods performed well across taxa, even with minimal data cleaning. Results suggest a machine-learning-based method applied to minimally cleaned data offers the best compromise between performance and species coverage. However, optimal data cleaning, training sample, and automation methods depend on the study group, intended applications, and expertise.  相似文献   
375.
李静  杜群 《中国环境管理》2019,11(1):117-122
我国南海渔业活动及其以外的人类活动产生的环境问题,严重污染了南海海域的水质,威胁着南海渔业资源的可持续发展。我国南海海域渔业环境保护法律体系已形成,提供了较为合理的制度安排。但仍存在一些法律问题,其中以环境影响评价制度、海洋环境监测制度和海水养殖污染防治制度等方面的问题较为突出。因此本文提出以下法律对策:明确渔业部门在环境影响评价制度中的法律地位,加强渔业海域环境监测的协调机制和完善海水养殖污染防治制度,以期依靠法治的力量保护南海渔业资源的可持续发展。  相似文献   
376.
As charismatic mega-fauna, sea turtles attract many volunteers to conservation programs. This article examines the ways in which volunteers value sea turtles, in the specific context of volunteers working with the Caribbean Conservation Corporation, at Tortuguero, Costa Rica. The complexity of volunteer values is explored using a qualitative approach. In-depth interviews with 31 volunteers were conducted in July of 1999 and 2000. Interviews probed, among other things, interest in sea turtles and their conservation, motives for participating, and the most gratifying parts of their volunteer experience. Results show that volunteers hold multiple and complex values for sea turtles, but particular values dominate. Results have implications for understanding human–environment relations and the emerging study of volunteer tourism. There are also management implications for volunteer programs hoping to attract participants.  相似文献   
377.
Sea turtles have a high reproductive output and high mortality at early stages of the life cycle. In particular, many nests are laid below or close to high tide lines, and subsequently large numbers of eggs may be inundated and destroyed. A common conservation procedure is to relocate such doomed eggs to higher ground. This article examines this practice in the light of recent data revealing that some individual turtles tend to nest relatively near the water and others relatively higher up the beach. Discussion is focused on the question of why apparently poor placement of nests has not been selected against. Comparison between the ecology of leatherback and hawksbill turtle nesting beaches suggests that predictability of environmental conditions on the nesting beaches has an important influence on patterns of nest-site selection. Options are outlined for the management of nesting beaches where a high proportion of turtle eggs is subject to destruction by flooding. An erratum to this article is available at.  相似文献   
378.
Introduction: Night work requires inversion of the natural, diurnal human activity-rest cycle and is associated with decreased alertness and some measures of performance, reduced safety, adverse health effects, and chronic disruption of the melatonin cycle that has been associated with increased risk for several major diseases. Previous studies show that red light exposures at night can promote alertness and improve performance while not negatively affecting melatonin secretion. Method: This ongoing crossover, mixed (within- and between-subjects) design field study is testing the efficacy and acceptance of red light delivered to day-shift and night-shift workers using personal light glasses while they are at work. Each participant experienced three lighting interventions at the eyes: red light (50 lx, 630 nm, the treatment intervention), blue light (50 lx, 460 nm, the positive control intervention), and dim white light (10 lx, 3,000 K, the placebo control). During the interventions, participants underwent visual performance testing, submitted salivary melatonin and cortisol samples, and provided subjective reports of sleepiness, sleep disturbance, and general health over the 20-week protocol. Due to the ongoing nature of the study, only the performance and subjective reports are presented here. Results: Preliminary results indicate that response times were improved by the red and blue interventions, but not accuracy and hit rates. Blue light was associated with improvements to self-reported sleep disturbances compared to dim light. Conclusions: These field results partially support our laboratory results that showed a positive effect of red light for promoting alertness and certain performance outcomes during the day and at night. Practical Applications: Red light may be used to improve response times in shift workers. Continued research will elucidate the lighting interventions’ effects on melatonin and objective sleep measures (actigraphy).  相似文献   
379.
为分析南海北部海域油气勘探保障建设选址的适宜性,在广泛研究备选区特征资料的基础上,基于层次分析法(Analytic Hierarchy Process, AHP)原理,以自然环境因素、开发环境因素、基础设施与投资情况以及其他因素作为一级评判准则,建立了包括12项二级评判准则的递进层次结构模型,并以永兴岛、赵述岛和晋卿岛作为3个假定备选区,来验证分析评价模型的有效性和可靠性。AHP评判结果显示,3个备选区的整体优劣指数依次为0.587 1, 0.212 1, 0.200 8;AHP模型的一致性比例CR值为0.020 3。通过分析和筛选影响远海油气勘探保障建设的选址因子,构建基于AHP原理的选址评价模型,可用于分析评价南海北部岛礁油气勘探保障建设选址的适宜性。  相似文献   
380.
• A dual “waste-to-resource” application of FO was proposed. • Performance of sea salt bittern as an economic FO draw solution was evaluated. • High quality struvite recovery from black water using FO was demonstrated. • Feed pH is a key factor to control the form of recovered phosphorous. A dual “waste-to-resource” innovation in nutrient enrichment and recovery from domestic black water using a sea salt bittern (SSB)-driven forward osmosis (FO) process is proposed and demonstrated. The performance of SSB as a “waste-to-resource” draw solution for FO was first evaluated. A synthetic SSB-driven FO provided a water flux of 25.67±3.36 L/m2⋅h, which was 1.5‒1.7 times compared with synthetic seawater, 1 M NaCl, and 1 M MgCl2. Slightly compromised performance regarding reverse solute selectivity was observed. In compensation, the enhanced reverse diffusion of Mg2+ suggested superior potential in terms of recovering nutrients in the form of struvite precipitation. The nutrient enrichment was performed using both the pre-filtered influent and effluent of a domestic septic tank. Over 80% of phosphate-P recovery was achieved from both low- and high-strength black water at a feed volume reduction up to 80%‒90%. With an elevated feed pH (~9), approximately 60%‒85% enriched phosphate-P was able to be recovered in the form of precipitated stuvite. Whereas the enrichment performance of total Kjeldahl nitrogen (TKN) largely differed depending on the strength of black water. Improved concentration factor (i.e., 3-folds) and retention (>60%) of TKN was obtained in the high-nutrient-strength black water at a feed volume reduction of 80%, in comparison with a weak TKN enrichment observed in low-strength black water. The results suggested a good potential for nutrient recovery based on this dual “waste-to-resource” FO system with proper management of membrane cleaning.  相似文献   
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