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81.
In 1968, excavations in the Climente II cave in the Iron Gates gorge of the River Danube in southwest Romania unearthed the skeleton of an adult male. The burial was assumed to be of Late Pleistocene age because of the presence of Late Upper Palaeolithic (LUP) artefacts in the cave. However, there was no strong supporting stratigraphic evidence, and the body position is reminiscent of Early Neolithic burial practice in the region. Here, we report the results of radiocarbon and stable isotope analyses of the Climente II skeleton, which show that the skeleton dates to the Bølling–Allerød Interstadial ~14,500 cal BP. This is several millennia older than any previously dated human remains from the Iron Gates region and confirms its status as the oldest known burial from Romania. The stable isotope results indicate a diet with an emphasis on aquatic resources, contrary to the commonly held view that the LUP inhabitants of the Iron Gates subsisted mainly by hunting large land mammals.  相似文献   
82.
Ethics and Environmental Attitudes With Implications for Economic Valuation   总被引:1,自引:0,他引:1  
This paper tests the hypothesis that different ethical belief systems are unrelated to the attitude an individual takes towards the environment. More specifically, the neoclassical economic approach is seen to require a belief in utilitarianism while many individuals may operate on the basis of a deontological or rights-based approach to decision-making. The concern with this relationship arises from the use of the cost–benefit analysis approach to environmental policy and the specific application of the contingent valuation method. Evidence is found to support the view that environmentalists choose to operate on a rights-based approach which rejects the relative welfare arguments of economics and positively attributes compensation to future generations for environmental damages. This implies that the contingent valuation of environmental attributes will lead to values which are biased towards technocentric optimists and against the environmental movement. In terms of policy, environmental management on the basis of totalling economic values is liable to be undemocratic because of the systematic exclusion of a section of the general public.  相似文献   
83.
Land application of coalbed natural gas (CBNG) co-produced water is a popular management option within northwestern Powder River Basin (PRB) of Wyoming. This study evaluated the impacts of land application of CBNG waters on soil chemical properties at five sites. Soil samples were collected from different depths (0-5, 5-15, 15-30, 30-60, 60-90, and 90-120 cm) from sites that were irrigated with CBNG water for 2 to 3 yr and control sites. Chemical properties of CBNG water used for irrigation on the study sites indicate that electrical conductivity of CBNG water (EC(w)) and sodium adsorption ratio of CBNG water (SAR(w)) values were greater than those recommended for irrigation use on the soils at the study sites. Soil chemical analyses indicated that electrical conductivity of soil saturated paste extracts (EC(e)) and sodium adsorption ratio of soil saturated paste extracts (SAR(e)) values for irrigated sites were significantly greater (P < 0.05) than control plots in the upper 30-cm soil depths. Mass balance calculations suggested that there has been significant buildup of Na in irrigated soils due to CBNG irrigation water as well as Na mobilization within the soil profiles. Results indicate that irrigation with CBNG water significantly impacts certain soil properties, particularly if amendments are not properly utilized. This study provides information for better understanding changes in soil properties due to land application of CBNG water. These changes must be considered in developing possible criteria for preserving fragile PRB ecosystems.  相似文献   
84.
85.
苏禄-苏拉威西海,及相邻的印度尼西亚海和南海,位于世界热带海洋生物多样性的中心.苏禄-苏拉威西海由3个人口众多的发展中国家--菲律宾、印度尼西亚和马来西亚所包围,该海及其毗连的沿海和陆地生态系养育着大约3300万人口,其中大部分人口的生计主要依赖于该海的可再生自然资源.  相似文献   
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87.
Problem: Workplace health and safety remains an important international socioeconomic issue, but the progressive declines in reported incidents may be slowing. The British Government has responded by launching a new policy initiative aimed at “Revitalizing Health and Safety” by establishing targets for improvement, strategies, and a series of action points, mainly targeting employers and organizational issues. This paper critically assesses the realities of implementing this policy with respect to the scientific base for each of the strategies. Method: Literature meta-analysis; analysis of policy. Results: Empirically proven determinants of workplace health and safety provide baselines for compensation and conditions of work, workforce characteristics, workplace characteristics, health and safety environment, political and economic factors, and industry characteristics. Support for different policy elements is varied and there are some significant gaps. Summary: An impressive body of research was found that offers a firm foundation for future developments. However, the need for work that is interdisciplinary, ordered, and collaborative is pressing. The need to move away from elegant but simplistic pictures of occupational health and safety (OHS) management practice, and to reflect true complexity is imperative. The reality of health and safety at work is that it is an issue that is taken lightly by those who do not practice or research safe and healthy working, and a serious issue for victims or relatives of victims of shoddy management. It remains one of the bastions of inequality of work worldwide. Impact on industry: The intent of governments in attempting to reinvigorate the suppression of workplace injury and illness is motivated by both social and economic imperatives. Motivation for organizations is not fully understood as there is no obvious business imperative. If organizations can further understand and provide a scientific justification for investment in OHS management, then governments' task will be made easier. By proving the value of OHS to management, we will demonstrate that organizations continue to present considerable hazards to their employees.  相似文献   
88.
MacNally R  Bowen M  Howes A  McAlpine CA  Maron M 《Ecology》2012,93(3):668-678
Some species have disproportionate influence on assemblage structure, given their numbers or biomass. Most examples of such "strong interactors" come from small-scale experiments or from observations of the effects of invasive species. There is evidence that entire avian assemblages in open woodlands can be influenced strongly by individual species over very large areas in eastern Australia, with small-bodied species (< 50 g) being adversely affected. We used data from repeated surveys in 371 sites in seven districts across a region from Victoria to Queensland (> 2000 km). A series of linked Bayesian models was used to identify large-bodied (> or = 50 g) bird species that were associated with changes in occurrence and abundance of small-bodied species. One native species, the Noisy Miner (Manorina melanocephala; family Meliphagidae), was objectively identified as the sole large-bodied species having similar detrimental effects in all districts, depressing occurrence of 57 of 71 small-bodied species. Adverse effects on abundances of small-bodied species were profound when the Noisy Miner occurred with mean site abundances > or = 1.6 birds/2 ha. The Noisy Miner may be the first species to have been shown to influence whole-of-avifauna assemblage structure through despotic aggressiveness over subcontinental scales. These substantial shifts in occurrence rates and abundances of small-bodied species flow on to alter species abundance distributions of entire assemblages over much of eastern Australia.  相似文献   
89.
Two non-lethal responses, avoidance andimmobility, were observed for thefreshwater gastropod Potamopyrgusantipodarum on exposure to dissolvedarsenic (As) as arsenate (As(V)) orarsenite (As(III)). Two differentpopulations of P. antipodarum, onewith a long history of exposure todissolved As from geothermal fluids andthe other with minimal exposure, werecompared to test for adaptation to As. Both snail populations avoided dissolvedAs(III), the more toxic form, at lowerconcentrations than As(V). As(V), theless toxic form, was avoided by both snailpopulations at much lower concentrationsthan those at which the snails becameimmobile. In contrast, the concentrationsof As(III) which caused avoidance werealmost the same as those which causedimmobility, implying that avoidance may notbe an effective response to protect thesesnails from exposure to As(III). Snailsfrom the exposed population avoided As(V)at about 20% of the concentration thatwas avoided by the snails from theunexposed population. At higherconcentrations of As(V) which causedimmobility, this difference in sensitivitypersisted up to an exposure time of 48 hours. After 96 hours exposure, however,both populations showed similarsensitivity. Snails from the exposedpopulation were more sensitive to As(III),both avoiding the As and becoming immobileat lower concentrations than were observedfor the same responses in the snails fromthe unexposed population. We suggest thatthe differences in sensitivity between thetwo populations could have been the resultof the higher soft body As burden of theexposed snails at the start of thelaboratory experiments.  相似文献   
90.
The inevitable need for freshwater to support the projected population growth along the ocean coast is an emerging issue of potential consequence to adjacent estuaries. A large and controversial water withdrawal/reservoir project in Virginia's coastal plain was the basis of science–management interactions that quantified the vulnerability of tidal freshwater nekton for a series of water withdrawal scenarios. Through progressive iterations of the regulatory review process, which in Virginia includes academic reviews of all aspects of projects proposed to affect the marine and estuarine environment, we developed a novel approach to modeling entrainment probabilities applicable to situations that lack a locally validated hydrodynamic model. The science/management interplay ultimately resulted in surface water allocation strategies that are balances to society and the affected natural environment. Model results showed that the probability of encounter (contact between an egg or larva and one or more units of the intake array) ranged from 1.71% under the conditions of a high river flow and low withdrawal rate to 99.99% under the conditions of a low river flow and high withdrawal rate. The collective body of scientific information was incorporated into regulatory conditions placed on water withdrawals that are designed to protect at least 95% of early life history stages within the intake array's zone of influence.  相似文献   
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