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111.
Death in fishing gear of non-target species (called ‘bycatch’) is a major concern for marine wildlife, and mostly worrying for long-lived species like cetaceans, considering their demographic characteristics (slow population growth rates and low fecundity). In European waters, cetaceans are highly impacted by this phenomenon. Under the Common Fishery Policy, the EC 812/2004 regulation constitutes a legal frame for bycatch monitoring on 5–10% of fishing vessels >15 m. The aim of this work was to compare parameters and bycatch estimates of common dolphins (Delphinus delphis) provided by observer programmes in France and UK national reports and those inferred from stranding data, through two approaches. Bycatch was estimated from stranding data, first by correcting effectives from drift conditions (using a drift prediction model) and then by estimating the probability of being buoyant. Observer programmes on fishing vessels allowed us to identify the specificity of the interaction between common dolphins and fishing gear, and provided low estimates of annual bycaught animals (around 550 animals year−1). However, observer programmes are hindered by logistical and administrative constraints, and the sampling scheme seems to be poorly designed for the detection of marine mammal bycatches. The analyses of strandings by considering drift conditions highlighted areas with high levels of interactions between common dolphins and fisheries. Since 1997, the highest densities of bycaught dolphins at sea were located in the southern part of the continental shelf and slope of the Bay of Biscay. Bycatch numbers inferred from strandings suggested very high levels, ranging from 3650 dolphins year−1 [2250–7000] to 4700 [3850–5750] dolphins year−1, depending on methodological choices. The main advantage of stranding data is its large spatial scale, cutting across administrative boundaries. Diverging estimates between observer programmes and stranding interpretation can set very different management consequences: observer programmes suggest a sustainable situation for common dolphins, whereas estimates based on strandings highlight a very worrying and unsustainable process. 相似文献
112.
《环境科学学报(英文版)》2023,35(4):321-332
Sludge is the by-product of wastewater treatment process. Multisource sludge can be defined as sludge from different sources. Based on the sludge properties of five typical cities in the Yangtze River basin, including Jiujiang, Wuhu, Lu'an, Zhenjiang and Wuhan, this study investigated and summarized the characteristic variations and distribution differences of multiple indicators and substances from municipal sludge, dredged sludge, and river and lake sediments. The results demonstrated pH of multisource sludge was relatively stable in the neutral range. Organic matter and water content among municipal sludge were high and varied considerably between different wastewater treatment plants. Dredged sludge had an obviously higher sand content and wider particle distribution, which could be considered for graded utilization depending on its size. The nutrients composition of river and lake sediments was usually stable and special, with lower nitrogen and phosphorus content but higher potassium levels. The sources of heavy metals and persistent organic pollutants in multisource sludge were correlated, generally much higher among municipal sludge than dredged sludge and river and lake sediments, which were the most important limitation for final land utilization. Despite various properties of multisource sludge, the final fate and destination have some overall similarities, which need to be supplemented and improved by standards and laws. The study provided a preliminary analysis of suitable technical routes for municipal sludge, dredged sludge, river and lake sediments based on their different characteristics respectively, which was of great significance for multisource sludge co-treatment and disposal in the future of China. 相似文献
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115.
In the Recôncavo of Bahia (located between 12°33′ and 13°10′S and 38°00′and 39°00′W), there are significant discharges of SO2 and NOx due to local, industrial and urban activities. The incoming air masses from the Atlantic Ocean are enriched with seaspray, which neutralizes part of the rain acidity. The extent of seaspray neutralization of rain acidity was quantified in four sites of the region, each with different loads of seaspray. Rain samples were obtained daily at the same time, integrating the precipitation of the previous 24 h, using wet-only collectors and analyzed for pH by potentiometry and for sodium by flame photometry. The amount of rain acidity in Recôncavo neutralized by seaspray ranged from <1% up to 88% and depended on the site. On average, neutralization ranged from 5% to 18%. 相似文献
116.
Current political conditions, primarily budgetary uncertainty, and the related reluctance to make funding commitments for
future generations, have raised questions about the costs of conservation and environmental protection that have not previously
been asked. As Federal investments are scrutinized and budgets become ever more constrained, the costs associated with environmental
requirements could begin to be of greater importance and to influence decisions on Federal projects. In response to concerns
about the U.S. Army Corps of Engineers (Corps) spending under the Endangered Species Act (P.L. 93-205) (ESA), a limited investigation
was performed to determine the accuracy of reported Corps expenditures. The investigation showed that, for particular groups
of species, actual conservation costs for threatened and endangered species may be twice the amounts previously reported in
the annual ESA expenditure reporting to the U.S. Fish and Wildlife Service. In light of this finding, the Corps has sought
a means to provide more accurate and consistent reporting of expenditures for addressing threatened and endangered species.
A Species Costs Template (template) has been developed to identify the types and magnitude of costs related to the ESA and
to counteract the impediments (legal, institutional, and practical) to underreporting costs. The template will be used by
the Corps for reporting ESA costs beginning with Fiscal Year 2005 (FY05) (reported in January 2006). Five broad categories
of expenditures (effects determination costs, ESA protection and conservation costs, equipment costs, opportunity costs, and
other species costs) are identified by the template. 相似文献
117.
Zoning and applying Limits of Acceptable Change (LAC) are two promising strategies for managing tourism in Marine Protected
Areas (MPAs). Typically, these management strategies require the collection and integration of ecological and socioeconomic
data. This problem is illustrated by a case study of Koh Chang National Marine Park, Thailand. Biophysical surveys assessed
coral communities in the MPA to derive indices of reef diversity and vulnerability. Social surveys assessed visitor perceptions
and satisfaction with conditions encountered on snorkelling tours. Notably, increased coral mortality caused a significant
decrease in visitor satisfaction. The two studies were integrated to prescribe zoning and “Limits of Acceptable Change” (LAC).
As a biophysical indicator, the data suggest a LAC value of 0.35 for the coral mortality index. As a social indicator, the
data suggest that a significant fraction of visitors would find a LAC value of under 30 snorkellers per site as acceptable.
The draft zoning plan prescribed four different types of zones: (I) a Conservation Zone with no access apart from monitoring
or research; (II) Tourism Zones with high tourism intensities at less vulnerable reefs; (III) Ecotourism zones with a social
LAC standard of <30 snorkellers per site, and (IV) General Use Zones to meet local artisanal fishery needs. This study illustrates
how ecological and socioeconomic field studies in MPAs can be integrated to craft zoning plans addressing multiple objectives. 相似文献
118.
姚杰 《安全.健康和环境》2022,22(1):22-25
针对消防救援车辆缺乏专业堵漏和倒罐装备、应急处置受限等问题,研究采用专用注压接头套组与消防车配合,通过向事故槽车阀门注水加压或惰性气体的方式实施辅助堵漏,能够实现因地制宜、快速有效地解决现场液化石油气大量泄漏的问题,降低事故危害。 相似文献
119.
This paper clarifies household income, living and working conditions of dumpsite waste pickers at Bantar Gebang final disposal site for municipal solid waste generated in Jakarta, and investigates the feasibility of integrating the informal sector into formal waste management in Indonesia. The first author did fieldwork for totally 16 months at the site and quantitative field surveys were conducted twice during the period. All respondents in the first round quantitative survey (n = 1390) were categorized as follows: waste pickers, family workers, wage labors, bosses, family of the bosses, housewives, pupils/students, preschoolers, the unemployed, and others. Based on the results of the second round quantitative survey (n = 69 households), their average household income was estimated to be approximately US 216 dollars per month (n = 59 households), which was virtually equivalent to the minimum wage in Jakarta in 2013. Living conditions of scavengers at the site were horrible, and their working conditions were dangerous due to medical waste and other sharp waste. Polluted groundwater was one of the serious environmental problems at the site. Despite the social, health and environmental problems, they were attracted to the freedom of entering the informal recycling system in Bantar Gebang and withdrawing from the system, in which a lot of opportunities were provided for the people having few marketable skills to obtain cash earnings. The freedom of their choice should be guaranteed as a prerequisite before integrating the informal sector into formal waste management. Furthermore, special attentions are required when incomes of scavengers are the same level as minimum wages and the national economy is rapidly growing, because scavengers cannot easily change their jobs due to few marketable skills. Indonesian national waste laws and regulations should be properly applied to facilitate a socialization process at final disposal sites. Measures need to be taken to prevent children from working as informal recycling actors, especially for waste pickers aged 15 or younger. 相似文献
120.
Discharges of nutrients, urea, dissolved organic matter and heavy metals by a sewage underwater pipeline are analysed in comparison to environmental conditions in a shallow coastal zone. Variable thermo-haline stratifications of the water column and currents in upper (2.62-34.97 cm s-1) and deeper (0.83-10.91 cm s-1) layers drive vertical diffusion and lateral transport of wastewaters. Loads of reactive phosphorus (0.13 tons d-1) and ammonium (1.62 tons d-1) by the pipeline are not negligible compared to the major river loads in the gulf. High concentrations of urea (≤11.51 μmol N dm-3) were found in the area of wastewater release. Ammonium uptake (6.14-534 nmol N dm-3 h-1) strongly exceeded nitrate uptake (0.19-138 nmol N dm-3 h-1), indicating that discharges of ammonium by the pipeline are actively assimilated by plankton community even at low levels of light. Distribution of Zn (≤27.7 ppb), Cu (≤25.6 ppb), Cd (≤0.80 ppb) and Pb (≤13.5 ppb) in the water column and the measurement of their complex-forming capacity in seawater did not indicate a persistent perturbation of the pelagic environment due to heavy metals. 相似文献