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1.
We present naturalist sightings of seabirds and marine mammals made during a research cruise with the IceAGE project off Iceland and the Faroe Islands during September 2011. Our findings from the obtained pelagic database are in-line with many other, more in-depth studies, showing major declines for pelagic seabirds and likely sea mammals, thus revising the role that Iceland now plays for such species. Northern Fulmar (Fulmarus glacialis) was the most recorded species, followed by different gulls, Black-legged Kittiwake (Rissa tridactyla) and Northern Gannet (Morus bassanus). However, Atlantic Puffin (Fratercula arctica) and Common Murre (Uria aalge) were only seen very rarely, and no observations were made of Dovekie (Alle alle) or Thick-billed Murre (U. lomvia). These observations were surprising since Iceland is known, so far, to host globally relevant populations of these auk species. A surprising high number of thirteen species of passerines were also detected offshore, mostly Wheatear (Oenanthe oenanthe), Meadow Pipit (Anthus pratensis) and Reed Bunting (Emberiza schoeniclus). Only a few marine mammals (Balaenoptera and Megaptera sp.) were encountered. Our detections present underestimates but are discussed in relation to ongoing and recently reported but dramatic anthropogenic changes of Iceland and in the North Atlantic overall. These include the substantial decrease in bird populations, overfishing and subsequent trophic cascades, as well as climate change, Arctic shipping and more industrial development to come. In light of these dramatic ecological changes, we conclude with an urgent request for an improved effective conservation management for Iceland, the North Atlantic and its stakeholders for directly related global governance to handle problems proactively.  相似文献   

2.
Shrub-Steppe Early Succession Following Juniper Cutting and Prescribed Fire   总被引:1,自引:0,他引:1  
Pinus-Juniperus L. (Piñon-juniper) woodlands of the western United States have expanded in area nearly 10-fold since the late 1800’s. Juniperus occidentalis ssp. occidentalis Hook. (western juniper) dominance in sagebrush steppe has several negative consequences, including reductions in herbaceous production and diversity, decreased wildlife habitat, and higher erosion and runoff potentials. Prescribed fire and mechanical tree removal are the main methods used to control J. occidentalis and restore sagebrush steppe. However, mature woodlands become difficult to prescribe burn because of the lack of understory fuels. We evaluated partial cutting of the woodlands (cutting 25–50% of the trees) to increase surface fuels, followed by prescribed fire treatments in late successional J. occidentalis woodlands of southwest Idaho to assess understory recovery. The study was conducted in two different plant associations and evaluated what percentage of the woodland required preparatory cutting to eliminate remaining J. occidentalis by prescribed fire, determined the impacts of fire to understory species, and examined early post-fire successional dynamics. The study demonstrated that late successional J. occidentalis woodlands can be burned after pre-cutting only a portion of the trees. Early succession in the cut-and-burn treatments were dominated by native annual and perennial forbs, in part due to high mortality of perennial bunchgrasses. By the third year after fire the number of establishing perennial grass seedlings indicated that both associations would achieve full herbaceous recovery. Cutting-prescribed fire combinations are an effective means for controlling encroaching late successional J. occidentalis and restoring herbaceous plant communities. However, land managers should recognize that there are potential problems associated with cutting-prescribed fire applications when invasive weeds are present.  相似文献   

3.
Enhanced concentrations of Fe, Zn, Mn, Pb, Cu, Cd and total hydrocarbons (THC) determined in fish samples from the Cross River system, Nigeria have been associated with clinical defects (nausea, headache, hepatitis, body rashes) observed in coastal residents who are the major consumers of the fish species. Fish samples were collected from ten locations with varying degrees of exposure to human activities. Heavy metal concentrations in fish followed the sequence: Fe>Zn>Mn>Pb>Cu>Cd with the highest concentration of 243 g/g (Fe) wet weight occurring in Tympanotonus sp. Fe levels were significantly (P<0.001) higher than other metals analysed. The sequence in total hydrocarbon concentrations according to fish species was in the order of O. niloticus (55.1 g/g) > E. fimbriata > P. elongatus > Portonus sp. > C. nigrodigitatus > Tympanotonus sp. Generally, the demersal species showed a marked potential for tolerating high levels of heavy metals while the pelagic species showed preference for the accumulation of hydrocarbons. The degree of contamination depended on pollutant type, fish species, sampling location, trophic level and their mode of feeding. The persistent accumulation and tolerable potential of Tympanotonus, Portonus and P. elongatus suggest that they might be effectively utilized as self-integrating indicators for time-series monitoring of the rate of recovery of the impacted ecosystem by heavy metals. Possible sources of pollutant include leachates from municipal dumps, used crankcase oils from fluvial discharges (mechanic workshops) and occasional oil spills.  相似文献   

4.
An elaborate set of criteria have been developed by fish managers and regulators to assure the accuracy, precision, representativeness, and robustness of survival compliance studies coordinated within the Federal Columbia River Power System in the northwestern USA. Dam passage survival, defined as survival from the dam face to the tailrace mixing zone, must be ≥96 % for spring out migrating juvenile salmonids [i.e., yearling Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss)] and ≥93 % for summer outmigrants (i.e., subyearling Chinook salmon). Survival must be estimated with a standard error ≤1.5 %. However, these quantitative benchmarks are only part of a multifaceted set of criteria, including representative dam operations, river discharge levels, and fish selection, along with tests of model validity that must be satisfied. These criteria are illustrated using acoustic-tag survival compliance studies conducted at The Dalles Dam on the Columbia River, 2010–2012. The results suggest evaluation criteria for survival compliance tests must balance the needs for rigor and robustness with the ability to reasonably perform the tests in naturally varying riverine systems.  相似文献   

5.
成都地区蔬菜中重金属污染分析与评价   总被引:38,自引:2,他引:38  
通过对成都地区的9种蔬菜152个样品的可食部分中重金属元素的分析研究,查明了蔬菜中重金属汞、砷、铅、锡的含量及分布特征。结果表明,锡和铅是成都地区蔬菜中的主要污染元素,在检测的蔬菜样品中,锡和铅的超标率分别为29.4%和22%,最高超标分别为5.60倍和2.86倍,汞和砷无超标现象。  相似文献   

6.
This study examines the effects of internal motivations and external pressures on the integration of environmental management (EM) practices within manufacturing operations in China. The moderating role of perceptions toward the regulatory process is also considered along with comparisons between wholly Chinese-owned and foreign-owned enterprises. From a sample of 131 manufacturing companies in the Guangzhou area, it was found that the salience of fees and fines has a strong positive influence on perceptions toward the regulator (the local Environmental Protection Bureau, EPB). This also has a positive effect on perceptions toward regulations themselves for foreign-owned enterprises. Business-case motivations for EM positively shape enterprise perceptions toward regulations, whereas risk-reduction motivations have a negative effect on perceptions toward regulations in foreign-owned enterprises. Enterprise perceptions toward the regulatory process have direct effects on the integration of EM practices in wholly Chinese-owned enterprises, but in opposite directions. While positive perceptions toward regulations have positive influence, positive perceptions toward regulators (i.e., the EPB) negatively affect it. Overall, these results indicated that promoting the adoption of EM practices depends on convincing business leaders that EM practices contribute to profit making. The regulatory process can potentially promote these practices, but measures need to be taken to ensure that the regulator is not co-opted by the regulated, especially in wholly Chinese-owned enterprises.  相似文献   

7.
Emerging challenges of risk management, environmental protection, and land-use planning requires integration of stakeholder values and expert judgment. The process of decision making in situation of high uncertainty can be assisted through the use of decision support systems (DSSs). Such DSSs are often based on tools for spatial data representation (GIS) and environmental models that are integrated using multi-criteria decision analysis (MCDA). This paper presents DecernsMCDA implementing all major types of multi-criteria methods and tools (AHP, MAUT, Outranking) under the same user interface. In addition to providing ability for testing model uncertainty associated with selection of specific MCDA algorithms, DecernsMCDA implements new algorithms for parameter uncertainty analysis based on probabilistic approaches and fuzzy sets. The paper illustrates application of DecernsMCDA for selecting remedial alternative at radiologically contaminated sites.  相似文献   

8.
This article measures the changes in energy use, blue water footprint, and greenhouse gas (GHG) emissions associated with shifting from current US food consumption patterns to three dietary scenarios, which are based, in part, on the 2010 USDA Dietary Guidelines (US Department of Agriculture and US Department of Health and Human Services in Dietary Guidelines for Americans, 2010, 7th edn, US Government Printing Office, Washington, 2010). Amidst the current overweight and obesity epidemic in the USA, the Dietary Guidelines provide food and beverage recommendations that are intended to help individuals achieve and maintain healthy weight. The three dietary scenarios we examine include (1) reducing Caloric intake levels to achieve “normal” weight without shifting food mix, (2) switching current food mix to USDA recommended food patterns, without reducing Caloric intake, and (3) reducing Caloric intake levels and shifting current food mix to USDA recommended food patterns, which support healthy weight. This study finds that shifting from the current US diet to dietary Scenario 1 decreases energy use, blue water footprint, and GHG emissions by around 9 %, while shifting to dietary Scenario 2 increases energy use by 43 %, blue water footprint by 16 %, and GHG emissions by 11 %. Shifting to dietary Scenario 3, which accounts for both reduced Caloric intake and a shift to the USDA recommended food mix, increases energy use by 38 %, blue water footprint by 10 %, and GHG emissions by 6 %. These perhaps counterintuitive results are primarily due to USDA recommendations for greater Caloric intake of fruits, vegetables, dairy, and fish/seafood, which have relatively high resource use and emissions per Calorie.  相似文献   

9.
Lead (Pb) contamination of the environment is an important human health problem. Children are vulnerable to Pb toxicity; it causes damage to the central nervous system and, in some extreme cases, can cause death. Lead is widespread, especially in the urban environment, and is present in the atmosphere, soil, water and food. Pb tends to accumulate in surface soil because of its low solubility, mobility, and relative freedom from microbial degradation of this element in the soil. Lead is present in soil as a result to weathering and other pedogenic processes acting on the soil parent material; or from pollution arising caused by the anthropogenic activities; such as mining, smelting and waste disposal; or through the adoption of the unsafe and unethical agricultural practices such as using of sewage sludge, and waste water in production of vegetable crops or cultivation of vegetables near highways and industry regions. Lead concentrations are generally higher in the leafy vegetables than the other vegetables. Factors affecting lead uptake included its concentration in the soil, soil pH, soil type, organic matter content, plant species, and unsafe agriculture practices. Generally, as Pb concentration increased; dry matter yields of roots, stems and leaves as well as total yield decreased. The mechanism of growth inhibition by lead involve: a decrease in number of dividing cells, a reduction on chlorophyll synthesis, induced water stress to plants, and decreased NO 3 - uptake, reduced nitrate and nitrite reductase activity, a direct effect of lead on protein synthesis, a decrease on the uptake and concentration of nutrients in plants. The strategies to minimize Pb hazard can be represented in: (a) Phytoremediation, through natural plants are able to bio-accumulate Pb in their above–ground parts, which are then harvested for removal such as, using Indian Mustard (Brassica juncea), Ragweed (Ambrosia artemisiifolia), Hemp Dogbane (Apocynum cannabium), or Poplar trees, which sequester lead in its biomass. (b) Good and ethical agricultural practices such as cultivation of vegetables crops as far from busy streets or highways and industry regions as well as nonuse of sewage sludge and waste water in cultivated soils. (c) Increasing the absorptive capacity of the soil by adding organic matter and humic acid. (d) Growing vegetable crops and cultivars with a low potential to accumulate lead, especially in soils exposed to atmospheric pollution. (e) Washing of leafy vegetables by water containing 1 % vinegar or peeling roots, tubers, and some fruits of vegetables before consumption may be an important factor in reducing the lead concentration.  相似文献   

10.
This ecophysiological research on the ash deposits from the Nikola Tesla–A thermal power station in Serbia covered 10 plant species (Tamarix gallica, Populus alba, Spiraea van-hauttei, Ambrosia artemisifolia, Amorpha fruticosa, Eupatorium cannabinum, Crepis setosa, Epilobium collinum, Verbascum phlomoides, and Cirsium arvense). This paper presents the results of a water regime analysis, photosynthetic efficiency and trace elements (B, Cu, Mn, Zn, Pb, and Cd) content in vegetative plant parts. Water regime parameters indicate an overall stability in plant-water relations. During the period of summer drought, photosynthetic efficiency (Fv/Fm) was low, ranging from 0.429 to 0.620 for all the species that were analyzed. An analysis of the tissue trace elements content showed a lower trace metal concentration in the plants than in the ash, indicating that heavy metals undergo major concentration during the combustion process and some are not readily taken up by plants. The Zn and Pb concentrations in all of the examined species were normal whereas Cu and Mn concentrations were in the deficiency range. Boron concentrations in plant tissues were high, with some species even showing levels of more than 100 g/g (Populus sp., Ambrosia sp., Amorpha sp., and Cirsium sp.). The presence of Cd was not detected. In general, it can be concluded from the results of this research that biological recultivation should take into account the existing ecological, vegetation, and floristic potential of an immediate environment that is abundant in life forms and ecological types of plant species that can overgrow the ash deposit relatively quickly. Selected species should be adapted to toxic B concentrations with moderate demands in terms of mineral elements (Cu and Mn).  相似文献   

11.
What is the relationship between biotechnology employees’ beliefs about the moral outcomes of a controversial transgenic research project and their attitudes of acceptance towards the project? To answer this question, employees (n=466) of a New Zealand company, AgResearch Ltd., were surveyed regarding a project to create transgenic cattle containing a synthetic copy of the human myelin basic protein gene (hMBP). Although diversity existed amongst employees’ attitudes of acceptance, they were generally: in favor of the project, believed that it should be allowed to proceed to completion, and that it is acceptable to use transgenic cattle to produce medicines for humans. These three items were aggregated to form a project acceptance score. Scales were developed to measure respondents’ beliefs about the moral outcomes of the project for identified stakeholders in terms of the four principles of common morality (benefit, non-harm, justice, and autonomy). These data were statistically aggregated into an Ethical Valence Matrix for the project. The respondents’ project Ethical Valence Scores correlated significantly with their project acceptance scores (r=0.64, p<0.001), accounting for 41% of the variance in respondents’ acceptance attitudes. Of the four principles, non-harm had the strongest correlation with attitude to the project (r=0.59), followed by benefit and justice (both r=0.54), then autonomy (r=0.44). These results indicate that beliefs about the moral outcomes of a research project, in terms of the four principles approach, are strongly related to, and may be significant determinants of, attitudes to the research project. This suggests that, for employees of a biotechnology organization, ethical reasoning could be a central mechanism for the evaluation of the acceptability of a project. We propose that the Ethical Valence Matrix may be used as a tool to measure ethical attitudes towards controversial issues, providing a metric for comparison of perceived ethical consequences for multiple stakeholder groups and for the evaluation and comparison of the ethical consequences of competing alternative issues or projects. The tool could be used to measure both public and special interest groups’ ethical attitudes and results used for the development of socially responsible policy or by science organizations as a democratizing decision aid to selection amongst projects competing for scarce research funds.  相似文献   

12.
Cochin estuary is one of the highly polluted aquatic systems of the southwest coast of India. The present study focuses on the assessment of heavy metals (Zn, Cd, Pb, and Cu) present in the sediments of Cochin estuary and the adjoining Periyar River. The sediments were analyzed for total metal content and various chemically bound fractions such as exchangeable, carbonate bound, easily reducible, organic, and residual. Total metal content of sediment was found higher than the average values reported from other Indian rivers. The mean concentration of Zn, Cd, Pb, and Cu in the sediments was 1,249.44, 9.5, 221.37, and 166.14???g/g, respectively. The results of sequential extraction showed that the concentration of Cd was high in the first two weakly bound fractions (exchangeable and carbonate bound) than the other metals, which are high in residual and organic bound fractions. Risk-assessment code analysis and environmental indices (enrichment factor and pollution load index) suggest that the sediments are highly polluted with metals, especially Cd.  相似文献   

13.
Determining reference concentrations in rivers and streams is an important tool for environmental management. Reference conditions for eutrophication-related water variables are unavailable for Brazilian freshwaters. We aimed to establish reference baselines for São Paulo State tropical rivers and streams for total phosphorus (TP) and nitrogen (TN), nitrogen-ammonia (NH4 +) and Biochemical Oxygen Demand (BOD) through the best professional judgment and the trisection methods. Data from 319 sites monitored by the São Paulo State Environmental Company (2005 to 2009) and from the 22 Water Resources Management Units in São Paulo State were assessed (N = 27,131). We verified that data from different management units dominated by similar land cover could be analyzed together (Analysis of Variance, P = 0.504). Cumulative frequency diagrams showed that industrialized management units were characterized by the worst water quality (e.g. average TP of 0.51 mg/L), followed by agricultural watersheds. TN and NH4 + were associated with urban percentages and population density (Spearman Rank Correlation Test, P < 0.05). Best professional judgment and trisection (median of lower third of all sites) methods for determining reference concentrations showed agreement: 0.03 &; 0.04 mg/L (TP), 0.31 &; 0.34 mg/L (TN), 0.06 &; 0.10 mg-N/L (NH4 +) and 2 &; 2 mg/L (BOD), respectively. Our reference concentrations were similar to TP and TN reference values proposed for temperate water bodies. These baselines can help with water management in São Paulo State, as well as providing some of the first such information for tropical ecosystems.  相似文献   

14.
This article explores certain aspects related to the environmental ethical message in the Encyclical Letter Laudato si, written in 2015 by Pope Francis, leader of the Catholic Church, and compares them to recent Green party political movements in Italy. Italy offers a unique case study in that the religious background of the country acts as an independent variable with respect to the social acceptance of current environmental issues. The ethical message in Laudato sì is compared to recent debates on the moral responsibility of the individual and/or institution towards environmental problems; a range of responsibilities assumed by institutions versus individuals with regards to environmental problems are analyzed. In conclusion, parallels are made between the abovementioned ethical debate and the ethical contents of the Encyclical Letter.  相似文献   

15.
Over the past several decades environmental ethics has grown markedly, normative ethics having provided essential grounding in assessing human treatment of the environment. Even a systematic approach, such as Paul Taylor’s, in a sense tells the environment how it is to be treated, whether that be Earth’s ecosystem or the universe itself. Can the environment, especially the ecosystem, as understood through the study of ecology, in turn offer normative and applied (environmental) ethics any edification? The study of ecology has certainly increased awareness of the fact that it is not possible for a moral agent within the ecosystem to step outside its intricate mesh of actions and events, of causes and effects. That is, absolutely everything that an agent can do can have some, often unforeseeable, outcome in the environment. An incompletely snuffed-out match tossed out a car window can cause a forest fire, which causes biome destruction, which causes x, y, and z. In sum, the ecosystem can edify ethics in terms of the scope of ethics, which remains an unsettled, if too-often ignored, matter. By such an inclusive view of moral scope, as derived in part from ecology and as presented here, the scope of moral behavior would include—whether or not adventitiously—every action an agent may do. By this view, moral scope is, in essence, unlimited. The article offers some ramifications of this view of moral scope.  相似文献   

16.
A literature survey on liquid-phase adsorption of selected heavy metals including Cu(II), Zn(II), Ni(II), Cd(II), Pb(II), Hg(II), and Cr(VI) on chitosan (CTS) and its derivatives was made from the viewpoint of adsorption capacity. This parameter was obtained from the Langmuir fit of isotherm data. The magnitude of adsorption capacity of heavy metals on pristine CTS was also used to discuss the mechanism of adsorption; that is, how many amino groups in CTS chains would coordinate with one heavy metal ion. Furthermore, a newly defined parameter, the approaching equilibrium factor RL, was proposed to quantitatively indicate the favorability of the related adsorption process and to judge the correctness of adsorption capacity determined by the Langmuir equation.  相似文献   

17.
Western North America is experiencing a dramatic expansion of piñon (Pinus spp.) and juniper (Juniperus spp.) (P-J) trees into shrub-steppe communities. Feature extracted data acquired from remotely sensed imagery can help managers rapidly and accurately assess this land cover change in order to manage rangeland ecosystems at a landscape-scale. The objectives of this study were to: (1) develop an effective and efficient method for accurately quantifying P-J tree canopy cover and density directly from high resolution photographs and (2) compare feature-extracted data to typical in-situ datasets used by land managers. Tree cover was extracted from aerial-photography using Feature Analyst®. Tree density was calculated as the sum of the total number of individual polygons (trees) within the tree cover output file after isolation using a negative buffer post-processing technique. Feature-extracted data were compared to ground reference measurements from Utah’s Division of Wildlife Resources Range Trend Project (DWR-RTP). We found that the proposed feature-extraction techniques used for measuring cover and density were highly correlated to ground reference and DWR-RTP datasets. Feature-extracted measurements of cover generally showed a near 1:1 relationship to these data, while tree density was underestimated; however, after calibration for juvenile trees, a near 1:1 relationship was realized. Feature-extraction techniques used in this study provide an efficient method for assessing important rangeland indicators, including: density, cover, and extent of P-J tree encroachment. Correlations found between field and feature-extracted data provide evidence to support extrapolation between the two approaches when assessing woodland encroachment.  相似文献   

18.
The act of animal killing affects the human psyche in manners that are culturally contingent. Throughout history, societal attitudes towards the taking of animal lives have mostly been based on deference and/or dominion. Postdomestic societies have evolved in fundamentally different ways. Meat production is abundant yet concealed, animals are categorized and stereotyped, and slaughter has become a highly disquieting activity. Increased awareness of postdomestic meat production systems raises a moral polemic and provokes disgust in some consumer segments. Overall, a heterogeneous set of solutions has emerged to deal with the societal upset and cognitive dissonance caused by animal slaughter. This includes the so-called carnism approach, a rise in animal welfare programs, a market demand for reassuring narratives (“story meat”), a rehabilitation of the metier of farmers and butchers, crowd butchering, neo-ritualism and home slaughter, the biotechnological exploration of “cultured meat” and “pain-free meat”, entomophagy, “meatless meat”, and the increasing proliferation of vegan and vegetarian lifestyles.  相似文献   

19.
In this article I discuss the thesis put forward by David Gunkel and Mark Coeckelbergh in their essay Facing Animals: A Relational, Other-Oriented Approach to Moral Standing. The authors believe that the question about the status of animals needs to be reconsidered. In their opinion, traditional attempts to justify the practice of ascribing rights to animals have been based on the search for what is common to animals and people. This popular conviction rests on the intuition according to which we tend to treat better those beings that are closer to us and resemble man in one way or the other. The attempts to ascribe a special status to animals are therefore based on the question “What properties does the animal have?”. However, the question is not well formulated because it leads to a number of ontological and epistemological problems. The question should rather be “What are the conditions under which an entity becomes a moral subject?”. Whilst fully subscribing to the suggestion, I cannot agree to the way the question is understood by both authors. I will demonstrate that the question opens up a transcendental dimension of reflections and may provide a clear justification of the need to engage in animal ethics. To do so, I will separate the easy and hard problems of animal ethics and use a different approach from the one suggested by Gunkel and Coeckelbergh to demonstrate how the need to pursue animal ethics may be justified.  相似文献   

20.
We examined whether differences in climate-friendly choices between the supporters of left-wing and right-wing ideologies are based on different moral foundations. Moreover, we compared general and issue-specific endorsement of moral foundations applied to climate change. Study 1 examined the endorsement of general moral foundations of university students living in Finland (N = 272). Individualizing foundations were associated with increased climate-friendly choices and binding foundations were associated with decreased climate-friendly choices; the endorsement of moral foundations made the effect of political orientation disappear. In Study 2 we developed and tested an issue-specific measure of moral foundations (N = 350). The issue-specific endorsement of both types of foundations was directly associated with increased climate-friendly consumption. Binding foundations were associated with the avoidance of climate-friendly choices through right-wing orientation. These findings increase our understanding of differences between general and issue-specific moral concerns and their association to political orientation and pro-environmental behavior.  相似文献   

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