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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.
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   

3.
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   

4.
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   

5.
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   

6.
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   

7.
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   

8.
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   

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.
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   

11.
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   

12.
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   

13.
The portrayal of animals in the media is often criticised for instrumentalising, objectifying and anthropomorphising animals (e.g. Hirschman and Sanders in Semiotica 115(1/2):53–79, 1997; Lerner and Kalof in Sociol Q 40(4):565–586, 1999; Stewart and Cole in Int J Multidiscip Res 12(4):457–476, 2009). Although we agree with this criticism, we also identify the need for a more substantiated approach to the moral significance of instrumentalisation, objectification and anthropomorphism. Thus, we propose a new framework which is able to address the morally relevant aspects of animal portrayal in the media. We closely examine the normative messages communicated by an unusual TV commercial in which an anthropomorphised piglet advertises organic beef. This serves as a case example to relate the philosophical and ethical concepts of objectification and anthropomorphism to each other and show how they can be applied. We conclude that the commercial conveys a message of animal instrumentalisation as being normatively correct within the constraint of good animal welfare. The depicted form of instrumentalisation is, nonetheless, associated with harm for the animals and thus, needs to overcome cognitive dissonance. To achieve this, animals are directly objectified by a trivialised and de-individualised portrayal. Moreover, animals are indirectly objectified even when they are anthropomorphised as they are granted significance only through being human-like. Thus, objectification and anthropomorphism are not opposing terms in our proposed framework. In addition, objectification, together with the reference to the dominant ideology, and combined with humorous anthropomorphism weakens scrutiny of these normative messages by the viewers. This eventually augments a decrease of moral concern for farmed animals in advertisement employing such portrayals.  相似文献   

14.
A growth room experiment was conducted to evaluate the bioavailability of Cu, Mn, Zn, Ca, Fe, K, Mg, P, S, As, B, Cd, Co, Cr, Hg, Mo, Na, Ni, Pb, and Se from a sandy loam soil amended with source-separated municipal solid waste (SSMSW) compost. Basil (Ocimum basilicum L.) and Swiss chard (Beta vulgaris L.) were amended with 0, 20, 40, and 60% SSMSW compost to soil (by volume) mixture. Soils and compost were sequentially extracted to fractionate Cu, Pb, and Zn into exchangeable (EXCH), iron- and manganese-oxide-bound (FeMnOX), organic-matter (OM), and structurally bound (SB) forms. Overall, in both species, the proportion of Cu, Pb, and Zn levels in different fractions followed the sequence: SB > OM > FeMnOX > EXCH for Cu; FeMnOX = SB > OM > EXCH for Pb; and FeMnOX > SB = EXCH > OM for Zn. Application of SSMSW compost increased soil pH and electrical conductivity (EC), and increased the concentration of Cu, Pb, and Zn in all fractions, but not EXCH Pb. Basil yields were greatest in the 20% treatment, but Swiss chard yields were greater in all compost-amended soils relative to the unamended soil. Basil plants in 20 or 40% compost treatments reached flowering earlier than plants from other treatments. Additions of SSMSW compost to soil altered basil essential oil, but basil oil was free of metals. The results from this study suggest that mature SSMSW compost with concentrations of Cu, Pb, Mo, and Zn of 311, 223, 17, and 767 mg/kg, respectively, could be used as a soil conditioner without phytotoxic effects on agricultural crops and without increasing the normal range of Cu, Pb, and Zn in crop tissue. However, the long-term effect of the accumulation of heavy metals in soils needs to be carefully considered.  相似文献   

15.
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   

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.
The toxicity and bioaccumulation of two heavy metals—lead (Pb) and cadmium (Cd)—in a semi-aquatic plant, Colocasia esculenta (L. Schott), from a synthetic heavy metal solution were studied. Young plants of equal size were grown hydroponically in shallow raceways containing Hoagland medium amended with 20, 40, and 60 mg l?1 of Pb and 2, 4, and 6 mg l?1 of Cd. The medium containing heavy metals was allowed to flow through the raceways with a change in influent heavy metal solution on every 5th day. The experiment was continued for 20 days. A set of control raceways—one comprised of nutrient medium with heavy metal supplements, devoid of plants, and another with the plants and nutrient medium having no metal supplement—was also simultaneously run. Chlorosis in the leaves was the prominent toxicity symptom observed due to Pb and Cd on the test plants. A significant decrease in the relative growth, biomass productivity, and total chlorophyll content were noticed in the plants with an increase in concentration of metal supplement in the solution and exposure time. Both metals accumulated to higher concentrations in the roots than in shoots, suggesting that the metals were bound to the root cells and their translocation to the leaves was limited. The results of the 20-day-long experiments indicate that from a phytoremediation perspective, C. esculenta is a promising plant species for remediation of wastewater polluted with lower concentrations of Pb and Cd.  相似文献   

18.
Two pulp and paper industrial wastes, lime mud (LM) and recovery boiler ash (RB), have low moisture contents, low heavy metal contaminations and contain various carbonate compounds which contribute to a high pH. Metal finishing wastewater (MF-WW) has a low pH, high levels of TDS and high contaminations from Cr, Cu, Pb and Zn. The heavy metals from MF-WW were removed by sorption and precipitation mechanisms. LM gave better results in removing heavy metals from MF-WW than RB. At a reaction time of 45 min, the maximum removal efficiencies for Cr (93%) and Cu (99%) were obtained at 110 g L−1 of LM, but at 80 g L−1 for Pb (96%) and Zn (99%). Treatment with LM gives a higher sludge volume than with RB. However, the leachability of heavy metals from LM is lower. Leachability of heavy metals in the sediment for all selected treatment conditions is within government standards.  相似文献   

19.
In 1906, Henry Stephens Salt published a short collection of essays that presented several rhetorically powerful, if formally deficient arguments for the vegetarian position. By interpreting Salt as a moral sentimentalist with ties to Aristotelian virtue ethics, I propose that his aesthetic argument deserves contemporary consideration. First, I connect ethics and aesthetics with the Greek concepts of kalon and kalokagathia that depend equally on beauty and morality before presenting Salt’s assertion: slaughterhouses are disgusting, therefore they should not be promoted. I suggest three areas of development since Salt’s death that could be fruitfully plumbed to rebuild this assertion into a contemporary argument: (1) an updated analysis of factory farm conditions, (2) insights from moral psychologists on the adaptive socio-biological benefits of disgust as a source of cognitive information, and (3) hermeneutical considerations about the role of the audience that allow blameworthiness for slaughterhouse atrocities to be laid upon the meat-eater.  相似文献   

20.
The Akaki River, laden with untreated wastes from domestic, industrial, and commercial sources, serves as a source of water for irrigating vegetable farms. The purpose of this study is to identify the impact of waste-water irrigation on the level of heavy metals and to predict their potential mobility and bioavailability. Zn and V had the highest, whereas Hg the lowest, concentrations observed in the soils. The average contents of As, Co, Cr, Cu, Ni, Zn, V, and Hg of both soils; and Pb and Se from Fluvisol surpassed the mean + 2 SD of the corresponding levels reported for their uncontaminated counterparts. Apparently, irrigation with waste water for the last few decades has contributed to the observed higher concentrations of the above elements in the study soils (Vertisol and Fluvisol) when compared to uncontaminated Vertisol and Fluvisol. On the other hand, Vertisol accommodated comparatively higher average levels of Cr, Cu, Ni, Zn, etc V, and Cd, whereas high contents of Pb and Se were observed in Fluvisol. Alternatively, comparable levels of Co and Hg were found in either soil. Except for Ni, Cr, and Cd in contaminated Vertisol, heavy metals in the soils were not significantly affected by the depth (0–20 and 30–50 cm). When the same element from the two soils was compared, the levels of Cr, Cu, Ni, Pb, Se, Zn, V, Cd at 0–20 cm; and Cr, Ni, Cu, Cd, and Zn at 30–50 cm were significantly different. Organic carbon (in both soils), CEC (Fluvisol), and clay (Vertisol) exhibited significant positive correspondences with the total heavy metal levels. Conversely, Se and Hg contents revealed perceptible associations with carbonate and pH. The exchangeable fraction was dominated by Hg and Cd, whereas the carbonate fraction was abounded with Cd, Pb, and Co. conversely, V and Pb displayed strong affinity to reducible fraction, where as Cr, Cu, Zn, and Ni dominated the oxidizable fraction. Cr, Hg, Se, and Zn (in both soils) showed preference to the residual fraction. Generally, a considerable proportion of the total levels of many of the heavy metals resided in non residual fractions. The enhanced lability is generally expected to follow the order: Cd > Co > Pb > Cu > Ni > Se > V and Pb > Cd > Co > Cu > Ni > Zn in Vertisol and Fluvisol, respectively. For the similar wastewater application, the soil variables influence the status and the distribution of the associated heavy metals among the different soil fractions in the study soils. Among heavy metals that presented relatively elevated levels and with potential mobility, Co, Cu, Ni (either soil), V (Vertisol), Pb, and Zn (Fluvisol) could pose health threat through their introduction into the food chain in the wastewater irrigated soils.  相似文献   

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