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71.
The contents from thick-billed murre (Uria lomvia) eggs collected at four Alaskan colonies in 2002 were analyzed for organic contaminants and carbon δ13C) and nitrogen (δ1?N) stable isotopes. Contaminant concentrations in the eggs varied from below detection limits to 230 ng g?1 wet mass for 4,4'-DDE in one egg from St Lazaria Island in the Gulf of Alaska. Eggs from this colony generally contained higher levels of contaminants and exhibited significantly different patterns compared to eggs from the Bering and Chukchi seas. Stable isotope values also varied geographically; however, these differences appeared to be related to differences in C and N baselines in the food webs instead of differences in prey. Contaminant and stable isotope correlations were inconclusive, suggesting that better information on regional food web differences and differential offloading of contaminants and stable isotopes to the eggs must be obtained before these kinds of data can be fully incorporated into seabird egg contaminant monitoring programs.  相似文献   
72.
Well-being is a positive physical, mental and social state and has increasingly become an area of interest to researchers and policy-makers internationally. This paper presents results from research that analyses the well-being benefits gained by different sections of society through viewing, engaging with, and accessing woodlands and forests in Britain. We draw on 31 studies undertaken since 2001 and present a meta-analysis of quantitative data and a meta-synthesis of qualitative data to explore the range of benefits and associated activities in woodlands, and their social distribution. We also present a state-of-the-art typology of well-being benefits for woodlands in Britain. The findings illustrate the wide range of well-being benefits gained by different social groups through various forms of engagement with and activities undertaken in woodlands. We illustrate the wide range of meanings and values attached to trees and woodlands across different social groups. The evidence also illustrates how carefully designed and targeted interventions can be particularly effective in enabling and encouraging people to visit woodland sites, to participate or get involved in new activities and, therefore, to realise a range of well-being benefits.  相似文献   
73.
This paper describes a recent study in the UK aimed at identifying how policy makers might more effectively encourage pro-environmental behaviours amongst their target audiences. The study included analysis and synthesis of theories and models of behaviour change, a range of current policy programmes and instruments and ‘real world’ practices of individuals, households, groups and organisations.The paper highlights some important considerations for future policy within the UK and, more widely, for other countries aiming to introduce comprehensive and multi-level policy programmes to encourage pro-environmental behaviours. To this end, it emphasises the complex and non-linear nature of environmental behaviours and, thus, the importance of adopting multi-levelled and multi-instrument integrated policies across whole systems of delivery.  相似文献   
74.
Using geographic information system, soil sampling, and statistical analysis to map anthropogenic effects on soil  相似文献   
75.
Chicken eggs from five different production types (conventional, omega-3 enriched, free range, organic and free run) were collected, when available, from three regions (west, central and east) of Canada to determine persistent organic pollutant (POP) concentrations. Total polychlorinated biphenyl (PCB) concentrations (∑37 congeners) in yolks from the eggs ranged from 0.162 ng g−1 lipid to 24.8 ng g−1 lipid (median 1.25 ng g−1 lipid) while the concentration of the sum of the 6 indicator PCBs ranged from 0.100 ng g−1 lipid to 9.33 ng g−1 lipid (median 0.495 ng g−1 lipid). Total polychlorinated dibenzo-p-dioxin/dibenzofuran (PCDD/F) concentrations ranged from 2.37 pg g−1 lipid to 382 pg g−1 lipid (median 9.53 pg g−1 lipid). The 2005 WHO toxic equivalency (TEQ) ranged from 0.089 pg TEQPCDD/F+dioxin-like[DL]-PCB g−1 lipid to 12.8 pg TEQPCDD/F+DL-PCB g−1 lipid (median 0.342 pg TEQPCDD/F+DL-PCB g−1 lipid). PCB and PCDD/F concentrations were significantly different (p < 0.001) in egg yolks from different regions of collection. In contrast to observations in Europe, PCB and PCDD/F concentrations in Canadian egg yolks were not impacted solely by the production type (e.g., conventional, free range, organic, etc.) used to maintain the laying chickens. Additionally, only one Canadian free range yolk from western Canada (12.8 pg TEQPCDD/F+DL-PCB g−1 lipid) exceeded the European toxic equivalent concentration limits for eggs (5 pg TEQPCDD/F+DL-PCB g−1 lipid). This differs from observations in Europe where free range/home produced eggs frequently have higher POP concentrations than eggs from other production types. Median PCB dietary intake estimates based on consumption of eggs were less than 10 ng d−1 while median PCDD/F intakes were less than 45 pg d−1.  相似文献   
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