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311.
Quantifying the nutritional quality of forage fish is integral for understanding upper trophic levels as forage fish are the dominant prey for top predator fish, marine mammals, and sea birds. Many existing reports documenting body composition of forage species are not comparable due to confounding effects. This study systematically assessed the variability in proximate composition and energy content of 16 forage species in southeastern Alaska (57.2626 N/133.7394 W) between 2001 and 2004. Variation in energy and lipid contents was related to habitat, epipelagic planktivores varying most, mesopelagics intermediate, and demersal species relatively invariable. Season was the greatest source of variation as a result of short growing seasons at high latitude and energy allocation strategies for reproduction and growth. Among species that varied seasonally, energy and lipid increased over summer and declined during winter. Annual differences in body composition occurred during periods of peak energy content. Sampling recommendations and guidance for bioenergetics models are provided.  相似文献   
312.
This study analyses disparities in the provision of environmental services in Jerusalem, specifically through the distribution of recycling bins. The allocation of recycling bins in Jerusalem is uneven. Some neighbourhoods have more than their share of infrastructure, while others do not have any recycling bins at all. The spatial distribution of recycling bins throughout the city is analysed across the ethno-religious and socioeconomic divides, enabling us to determine whether the opportunity to recycle is a right or a privilege. The findings demonstrate that the Arab areas are literally not serviced. Ultra-Orthodox (Haredi) Jewish neighbourhoods are discriminated against unless socioeconomic levels and population size are controlled. Therefore, waste-management policies reproduce social inequalities resulting in environmental injustice. Due to the fact that recycling in Jerusalem is voluntary and not obligatory, and that in general the public wants to recycle, the opportunity to recycle is indeed a privilege.  相似文献   
313.
Bikini Island was contaminated on March 1, 1954 by the Bravo detonation (U.S. nuclear test series, Castle) at Bikini Atoll. About 90% of the estimated dose from nuclear fallout to potential island residents is from cesium-137 ((137)Cs) transferred from soil to plants that are consumed by residents. Thus, radioecology research efforts have been focused on removing (137)Cs from soil and/or reducing its uptake into vegetation. Most effective was addition of potassium (K) to soil that reduces (137)Cs concentration in fruits to 3-5% of pretreatment concentrations. Initial observations indicated this low concentration continued for some time after K was last applied. Long-term studies were designed to evaluate this persistence in more detail because it is very important to provide assurance to returning populations that (137)Cs concentrations in food (and, therefore, radiation dose) will remain low for extended periods, even if K is not applied annually or biennially. Potassium applied at 300, 660, 1260, and 2070 kg ha(-1) lead to a (137)Cs concentration in drinking-coconut meat that is 34, 22, 10, and about 4% of original concentration, respectively. Concentration of (137)Cs remains low 8-10 y after K is last applied. An explanation for this unexpected result is discussed.  相似文献   
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