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141.
JEFFREY A. McNEELY PROMILA KAPOOR-VIJAY† LU ZHI‡ LINDA OLSVIG-WHITTAKER§ KASHIF M. SHEIKH ANDREW T. SMITH†† 《Conservation biology》2009,23(4):805-810
Abstract: With about half the world's human population and booming economies, Asia faces numerous challenges to its biodiversity. The Asia Section of the Society for Conservation Biology has identified some key policy issues in which significant progress can be made. These include developing new sources of funding for forest conservation; identifying potential impacts of energy alternatives on the conservation of biodiversity; curbing the trade in endangered species of plants and animals; a special focus on the conservation of mountain biodiversity; enhancing relevant research; ensuring that conservation biology contributes to major international conventions and funding mechanisms; using conservation biology to build a better understanding of zoonotic diseases; more effectively addressing human–animal conflicts; enhancing community-based conservation; and using conservation biology to help address the pervasive water-deficit problems in much of Asia. These challenges can be met through improved regional cooperation among the relevant stakeholders . 相似文献
142.
ROBERT C. BARBOUR‡ LYNNE G. FORSTER SUSAN C. BAKER† DOROTHY A. STEANE BRADLEY M. POTTS 《Conservation biology》2009,23(5):1146-1155
Abstract: The developing field of community genetics has the potential to broaden the contribution of genetics to conservation biology by demonstrating that genetic variation within foundation plant species can act to structure associated communities of microorganisms, invertebrates, and vertebrates. We assessed the biodiversity consequences of natural patterns of intraspecific genetic variation within the widely distributed Australian forest tree, Eucalyptus globulus. We assessed genetic variation among geographic races of E. globulus (i.e., provenances, seed zones) in the characteristics of tree‐trunk bark in a 17‐year‐old common garden and the associated response of a dependent macroarthropod community. In total, 180 macroarthropod taxa were identified following a collection from 100 trees of five races. We found substantial genetically based variation within E. globulus in the quantity and type of decorticating bark. In the community of organisms associated with this bark, significant variation existed among trees of different races in composition, and there was a two‐fold difference in species richness (7–14 species) and abundance (22–55 individuals) among races. This community variation was tightly linked with genetically based variation in bark, with 60% of variation in community composition driven by bark characteristics. No detectable correlation was found, however, with neutral molecular markers. These community‐level effects of tree genetics are expected to extend to higher trophic levels because of the extensive use of tree trunks as foraging zones by birds and marsupials. Our results demonstrate the potential biodiversity benefits that may be gained through conservation of intraspecific genetic variation within broadly distributed foundation species. The opportunities for enhancing biodiversity values of forestry and restoration plantings are also highlighted because such planted forests are increasingly becoming the dominant forest type in many areas of the world. 相似文献
143.
Hugo Fjelsted Alrøe Mette Vaarst Erik Steen Kristensen 《Journal of Agricultural and Environmental Ethics》2001,14(3):275-299
The recent development and growth oforganic livestock farming and the relateddevelopment of national and internationalregulations has fueled discussions amongscientists and philosophers concerning theproper conceptualization of animal welfare.These discussions on livestock welfare inorganic farming draw on the conventionaldiscussions and disputes on animal welfare thatinvolve issues such as different definitions ofwelfare (clinical health, absence of suffering,sum of positive and negative experiences,etc.), the possibility for objective measuresof animal welfare, and the acceptable level ofwelfare. It seems clear that livestock welfareis a value-laden concept and that animalwelfare science cannot be made independent ofquestions of values and ethics. The questioninvestigated here is whether those values thatunderpin organic farming, in particular, alsoaffect the interpretation of livestock welfare,and, if so, how. While some of the issuesraised in connection with organic farming arerelatively uncontroversial, others are not. Theintroduction of organic farming values seems tointroduce new criteria for what counts as goodanimal welfare, as well as a different ethicalbasis for making moral decisions on welfare.Organic farming embodies distinctive systemicor communitarian ethical ideas and the organicvalues are connected to a systemic conceptionof nature, of agriculture, of the farm, and ofthe animal. The new criteria of welfare arerelated to concepts such as naturalness,harmony, integrity, and care. While the organicvalues overlap with those involved in theconventional discussion of animal welfare, someof them suggest a need to set new prioritiesand to re-conceptualize animal welfare – forexample, with respect to ``naturalness,' inrelation to the possibilities for expression ofnatural behavior and in relation to animalintegrity as a concept for organismic harmony.The organic perspective also seems to suggest awider range of solutions to welfare problemsthan changes in farm routines or operations onthe animals. The systemic solutions include thechoice and reproduction of suitable breeds,changes in the farm structure, and changes inthe larger production and consumption system – including consumer perceptions andpreferences. But the organic values may alsocall for sacrifices of individual welfare in aconventional sense in order to advance welfarefrom the perspective of organic farming.Whether this is good or bad cannot be decidedwithout entering into an inquiry and discussionof the values and ethics involved. 相似文献
144.
Seidel B Alm M Peters R Kördel W Schäffer A 《Environmental science and pollution research international》2006,13(2):125-130
Background Due to the bovine spongiform encephalopathy (BSE), specified risk material (SRM) as well as animal meat and bone meal (MBM)
are banned from the food and feed chain because of a possible infection with pathogenic prions (PrPSc). Nowadays, prions are
widely accepted to be responsible for TSE(transmissible spongiform encephalopathies)-caused illnesses like BSE and scrapie,
and especially for the occurrence of the new variant of CJD in humans. Presently, SRM and MBM are burnt under high temperatures
to avoid any hazards for humans, animals or the environment. The aim of this study was to evaluate a method using animal fat
separated from Category I material which includes SRM and the carcasses of TSE-infected animals, or animals suspected of being
infected with TSE, as a source for producing biodiesel by transesterification, analogous to the biodiesel process using vegetable
oil.
Methods For this purpose, animal fat was spiked with scrapie-infected hamster brain equivalents – as representative for a TSE-infected
animal – and the biodiesel manufacturing process was downscaled and performed under lab-scale conditions.
Results and Discussion The results analysed by Western blotting showed clearly that almost each single step of the process leads to a significant
reduction of the concentration of the pathogenic prion protein (PrPSc) in the main and side-products.
Conclusion The data revealed that the biodiesel production, even from material with a high concentration of pathogenic prions, can be
considered as safe.
Recommendations and Outlook The obtained results indicated that biodiesel produced from prion-contaminated fat was safe under the tested process conditions.
However, it has to be pointed out that the results cannot be generalized because a different process control using other conditions
may lead to different results and then has to be analysed independently. It is clear that the production of biodiesel from
high risk material represents a more economic usage than the combustion of such material. 相似文献
145.
Jo Murphy-Lawless 《Journal of Agricultural and Environmental Ethics》2004,17(4-5):385-403
The recent crises of BSE and FMD in the United Kingdom have revealed widespread concerns on the part of farmers and consumers about government regulations and handling of animal movements, animal welfare, and food safety. Both crises raised issues of government accountability and the lack of openness in public debate. The issues of democratic process and decision-making were especially strong in relation to the mass slaughter policy of the government to control FMD. This article explores public disquiet about these matters, as expressed through the reports of two public inquiries, and the perceived links between government decision-making and the needs of global agribusiness, to the detriment of family farms and animal welfare. In light of the growing evidence about the environmental and economic costs of agribusiness, the argument is made that strong programs of citizen action, such as the Devon Foot and Mouth Inquiry, that are grounded in an ethical stance on animal welfare can challenge the perspectives of central governments about concepts of cost, efficiency, and safety in agriculture. 相似文献
146.
In Rocky Mountain National Park (RMNP), aspen (Populus tremuloides Michx.) has been observed to be declining on elk (Cervus elaphus nelsoni) winter range for many decades. To support elk management decisions, the SAVANNA ecosystem model was adapted to explore interactions between elk herbivory and aspen dynamics. The simulated probability of successful vegetative regeneration for senescent aspen stands declines sharply when elk densities reach levels of 3–5 elk/km2, depending on model assumptions for the seasonal duration of elk foraging activities. For aspen stands with a substantial component of younger trees, the simulated regeneration probability declines more continuously with increasing elk density, dropping below 50% from densities at 8–14 elk/km2.At the landscape scale, simulated aspen regeneration probability under a scenario of extensive seasonal use was little affected by elk population level, when this level was above 300–600 elk (25%–50% current population) over the ca. 107 km2 winter range. This was because elk distribution was highly aggregated, so that a high density of elk occupied certain areas, even at low population levels overall. At approximately current elk population levels (1000–1200 elk), only 35%–45% of senescent aspen stands are simulated as having at least a 90% probability of regeneration, nearly all of them located on the periphery of the winter range. Successful management for aspen persistence on core winter range will likely require some combination of elk population reduction, management of elk distribution, and fencing to protect aspen suckers from elk browsing. 相似文献
147.
Bernard E. Rollin 《Journal of Agricultural and Environmental Ethics》1989,2(3):225-234
It is patent that society is evolving an ethic for the treatment of animals which goes well beyond the standard prohibitions against cruelty. This new ethic for animals takes the consensus ethic for the treatment of humans in society and extends it,mutatis mutandis, to the treatment of animals. Though this ethic has been applied first to research animals, its extension to agricultural animals is inevitable, and has already begun. This article explores the extent to which veterinary medicine and animal science, the major scientific fields relevant to animal agriculture, can accommodate the emerging ethic. 相似文献
148.
149.
In her recent Counter-Reply to my views, Evelyn Pluhar defends her use of literature on nutrition and restates her argument for moral vegetarianism. In his Vegan Ideal article, Gary Varner claims that the nutrition literature does not show sufficient differences among women, men, and children to warrant concern about discrimination. In this response I show how Professor Pluhar continues to draw fallacious inferences: she begs the question on equality, avoids the main issue in my ethical arguments, argues from irrelevancies, misquotes her sources, equivocates on context, confuses safety with morality, appeals to fear, confuses correlation with cause, fails to evaluate scientific studies, draws hasty conclusions from insufficient data, ignores a large amount of data which would call her views into question, does not follow good scientific or moral argumentation, objectionably exceeds the limits of her expertise, and resorts to scapegoating. I also argue that Professor Varner fails to make his case because he offers virtually no evidence from scientific studies on nutrition, relies on outdated and fallacious sources, makes unsupported claims, ignores evidence that would contravene his claims, draws hasty conclusions based on weakly supported hypotheses rather than facts, employs a double standard, appeals to ignorance, does not evaluate arguments from his sources, and makes anad hominem attack on a respected nutritionist when his focus should be on evaluating the evidence and arguments from the scientific studies themselves. Neither Varner nor Pluhar have responded sufficiently to the real issue in my arguments, that of discrimination and bias in the vegan ideal. 相似文献
150.
Gary E. Varner 《Journal of Agricultural and Environmental Ethics》1994,7(1):29-40
Much of the scientific literature on vegetarian nutrition leaves one with the impression that vegan diets are significantly more risky than omnivorous ones, especially for individuals with high metabolic demands (such as pregnant or lactating women and children). But nutrition researchers have tended to skew their study populations toward new vegetarians, members of religious sects with especially restrictive diets and tendencies to eschew fortified foods and medical care, and these are arguably the last people we would expect to thrive on vegan diets. Researchers also have some tendency to play up weakly confirmed risks of vegan dietsvis-à-vis equally weakly confirmed benefits. And, in spite of these methodological and rhetorical biases, for every nutrient which vegans are warned to be cognizant of, there is reason to believe that they are not at significantly greater risk of nutritional deficiency than omnivores. 相似文献