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1.
Scholarly critics such as Wendell Berry, as well as the popular media, frequently refer to problems associated with agriculture as the agricultural crisis or the farm crisis. Despite the identification of a problem or problems as symptomatic of this crisis, scant attention is paid to why the situation is a social crisis as opposed to a problem, tragedy, trend, or simple change in the structure of agriculture. This paper analyzes the use of social crisis as applied to the state of modern agriculture and, by extension, other crises such as those in legitimation and morality. It concludes that, although important social values associated with farming as a way of life may be in danger of being lost, the crisis we may be facing with respect to agriculture is more properly understood as a sociopolitical crisis that has broader implications than simply the loss of farms or traditional farming values. Indeed, what is in danger of being lost is our ability to affect a secure and sustainable political-economic system.  相似文献   

2.
The synthetic field of conservation biology uses principles derived from many different disciplines to address biodiversity issues. Many of these principles have come from ecology, and two simple ones that seem to relate to many issues involving the utility industry are: (1) Everything is interconnected (and should usually stay that way), and (2) We can never do merely one thing. The first principle can be applied to both the biotic and physical environments that are impacted by industrial activities. Habitat fragmentation and the loss of physical and biotic connectedness that results are frequently associated with transmission rights-of-way. These problems can be reduced—or even turned into conservation benefits—by careful planning and creative management. The second principle applies to the utility industry's programs to deal with carbon released by burning fossil fuels. Ecological knowledge can allow these programs to contribute to the preservation of biodiversity in addition to addressing a pollution problem. Without careful ecological analyses, industry could easily create new problems while implementing solutions to old ones.  相似文献   

3.
Kathryn Paxton George has recently argued that vegetarianism cannot be a moral obligation for most human beings, even if Tom Regan is correct in arguing that humans and certain nonhuman animals are equally inherently valuable. She holds that Regan's liberty principle permits humans to kill and eat innocent others who have a right to life, provided that doing so prevents humans from being made worse off. George maintains that obstaining from meat and dairy products would in fact make most humans worse off. I argue that Regan's liberty principle either contradicts his equal rights view or does not permit the slaughter of another for food. I show that a different view recognizing the moral rights of nonhumans but according them less value than normal adult humans, the unequal rights view, would permit such action if human survival or health depended upon it. However, it would also permit the slaughter of innocent humans in the same circumstances. Finally, I argue that current nutritional research does not support George's contention that most humans would suffer if they ceased eating other animals and their products.  相似文献   

4.
Naturalness In Biological Conservation   总被引:1,自引:0,他引:1  
Conservation scientists are arguing whether naturalness provides a reasonable imperative for conservation. To clarify this debate and the interpretation of the term natural, I analyze three management strategies – ecosystem preservation, ecosystem restoration, and ecosystem engineering – with respect to the naturalness of their outcomes. This analysis consists in two parts. First, the ambiguous term natural is defined in a variety of ways, including (1) naturalness as that which is part of nature, (2) naturalness as a contrast to artifactuality, (3) naturalness as an historical independence from human actions, and (4) naturalness as possession of certain properties. After that, I analyze the different conceptions with respect to their implications for the three management strategies. The main conclusion is that there exists no single conception of naturalness that could distinguish between the outcomes of the three management methods. Therefore, as long as the outcomes of the different methods are regarded as being of a different value in conservation, we should either abandon the idea of naturalness as the guiding concept in conservation or use the term natural only in the ways that take both its historical and feature dependent meanings into consideration.  相似文献   

5.
Bioassessment is used worldwide to monitor aquatic health but is infrequently used with risk-assessment objectives, such as supporting the development of defensible, numerical water-quality criteria. To this end, we present a generalized approach for detecting potential ecological thresholds using assemblage-level attributes and a multimetric index (Index of Biological Integrity—IBI) as endpoints in response to numerical changes in water quality. To illustrate the approach, we used existing macroinvertebrate and surface-water total phosphorus (TP) datasets from an observed P gradient and a P-dosing experiment in wetlands of the south Florida coastal plain nutrient ecoregion. Ten assemblage attributes were identified as potential metrics using the observational data, and five were validated in the experiment. These five core metrics were subjected individually and as an aggregated Nutrient–IBI to nonparametric changepoint analysis (nCPA) to estimate cumulative probabilities of a threshold response to TP. Threshold responses were evident for all metrics and the IBI, and were repeatable through time. Results from the observed gradient indicated that a threshold was 50% probable between 12.6 and 19.4 g/L TP for individual metrics and 14.8 g/L TP for the IBI. Results from the P-dosing experiment revealed 50% probability of a response between 11.2 and 13.0 g/L TP for the metrics and 12.3 g/L TP for the IBI. Uncertainty analysis indicated a low (typically 5%) probability that an IBI threshold occurred at 10 g/L TP, while there was 95% certainty that the threshold was 17 g/L TP. The weight-of-evidence produced from these analyses implies that a TP concentration > 12–15 g/L is likely to cause degradation of macroinvertebrate assemblage structure and function, a reflection of biological integrity, in the study area. This finding may assist in the development of a numerical water-quality criterion for TP in this ecoregion, and illustrates the utility of bioassessment to environmental decision-making.  相似文献   

6.
This article examines the likely impacts of the United States' new federalism on natural hazard land use management in Colorado. Flood and avalanche hazard programs are the focus of the study Both short- and long-term effects of changes in funding are discussed, and the conclusions summarize probable positive and negative program impacts for the state. These results may help researchers and state authorities mitigate similar effects in their states prior to the enactment of new federalism.  相似文献   

7.
This paper presents a new habitat suitability modeling method whose main properties are as follows: (1) It is based on the density of observation points in the environmental space, which enables it to fit complex distributions (e.g. nongaussian, bimodal, asymmetrical, etc.). (2) This density is modeled by computing the geometric mean to all observation points, which we show to be a good trade-off between goodness of fit and prediction power. (3) It does not need any absence information, which is generally difficult to collect and of dubious reliability. (4) The environmental space is represented either by an expert-selection of standardized variables or the axes of a factor analysis [in this paper we used the Ecological Niche Factor Analysis (ENFA)].We first explain the details of the geometric mean algorithm and then we apply it to the bearded vulture (Gypaetus barbatus) habitat in the Swiss Alps. The results are compared to those obtained by the median algorithm and tested by jack-knife cross-validation. We also discuss other related algorithms (BIOCLIM, HABITAT, and DOMAIN). All these analyses were implemented into and performed with the ecology-oriented GIS software BIOMAPPER 2.0.The results show the geometric mean to perform better than the median algorithm, as it produces a tighter fit to the bimodal distribution of the bearded vulture in the environmental space. However, the median algorithm being quicker, it could be preferred when modeling more usual distribution.  相似文献   

8.
The Environmental Impact Statement (EIS) attempts to portray the current character of a given ecosystem. This provides a Baseline against which future possible changes can be assessed. Ecosystems, however, are dynamic and in a constant state of change. Consequently, data representing a single year reflect conditions only for that year and can be misleading if compared against any other year. In addition to this temporal variation, considerable spacial variation exists in species composition and cover. Ample sampling is required to compensate for this heterogeneity. Variation, or background noise, can be minimized by the use of similarity indexes and sampling over a period of at least two years.  相似文献   

9.
Conclusion As a final thought, I want to conclude with the cliche that a problem recognized is half solved. Certainly, I cannot be accused of laying out a solution to solving the major fisheries management problems, but it is hoped that the problems managers face are now clearer. The complexity of fisheries assystems to be managed is clear to even the most casual observer. The second point, a broad theory of fisheries management, should provide a framework to categorize all of the disjointed activities that we associate with management of our fisheries resources.  相似文献   

10.
We studied the effects of spatial and temporal timber harvesting constraints on competing objectives of sustaining wildlife habitat supply and meeting timber harvest objectives in a boreal mixedwood forest. A hierarchical modeling approach was taken, where strategic and tactical level models were used to project blocking and scheduling of harvest blocks. Harvest block size and proximity, together with short- and long-term temporal constraints, were adjusted in a factorial manner to allow creation of response–surface models. A new measure of the habitat mosaic was defined to describe the emergent pattern of habitat across the landscape. These models, together with multiple linear regression, were used to provide insight on convergence or divergence between spatial objectives. For example, green-up delay (defined as time required before a harvest block adjacent to a previously logged block can be scheduled for harvest) had an adverse effect on the amount of annual harvest area that could be allocated and blocked spatially, and habitat supply responded in an opposite direction to that of wood supply, where caribou, moose wintering, and marten habitat supply increased when harvest blocks were further apart, maximum block size smaller, and both a green-up delay and mesoscale stratification were applied. Although there was no solution space free of conflicts, the analysis suggests that application of the mesoscale stratification, together with a diversity of harvest block sizes and a between-harvest block proximity of 250 m, will perform relatively well with respect to wood supply objectives, and at the same time create a less fragmented landscape that better reflects natural forest patterns.  相似文献   

11.
Nature quality in relation to farming is a complex field. It involves different traditions and interests, different views of what nature is, and different ways of valuing nature. Furthermore there is a general lack of empirical data on many aspects of nature quality in the farmed landscape. In this paper we discuss nature quality from the perspective of organic farming, which has its own values and goals in relation to nature – the Ecologist View of Nature. This is in contrast to the Culturist View characteristic of much conventional agriculture and the Naturalist View characteristic of the traditional biological approach to nature quality. This threefold distinction forms a framework for exploration of nature quality criteria in the farmed landscape. The traditional work on nature quality has mainly focused on biological interests based on a Naturalist View of Nature. In this paper we will explore how criteria for nature quality based on the Ecologist View can be developed and thereby feed into the ongoing discussion of the development of the organic farming practices. We suggest additional criteria for nature quality based on an Ecologist View of Nature: biodiversity, habitat diversity, extent and structure, functional integrity of habitats and agro-ecosystems, landscape integrity, accessibility, and experientiality. The larger set of Naturalist and Ecologist criteria can provide a wider and more balanced basis for developing nature quality indicators that are relevant in the farmed landscapes. This broader approach to nature quality is also expected to benefit the general societal discussions and decisions on farming and nature.  相似文献   

12.
A three-tiered structure of land-use and environmental management is here proposed for Australia. The structure is based on the idea that environment means the environment of people, and that environmental problems arise when a change in the interaction between people and their environment leads to conflicts about the use of land and resources. The heterogeneity of society means that a range of human aspirations and value systems must be satisfied by environmental managers. Existing methods of environmental management fail to achieve these objectives, due to inadequate perception of environmental problems by decision-makers, and the inability of currently available impact assessment techniques to resolve human conflicts associated with the use of land and resources. The main work of planning and managing land use and the environment would be carried out by regional authorities, supported by federal and state policy. Examples are given of moves towards regional administration in England and Wales, Western Australia, Australia and New Zealand. Community participation in the decision-making process is essential and can be achieved by electoral representation to the authoritative bodies and through procedures that ensure informed public comment on planning proposals.  相似文献   

13.
Different criteria have been proposed for the rapid ecological evaluation of wooded areas. It is difficult, however, to determine the criteria most likely to yield results similar to those that would be obtained through detailed surveys and exhaustive evaluation. In order to identify such synthetic criteria, data from a detailed evaluation of Montreal Urban Community woodlots were studied with the help of multivariate analysis. This detailed evaluation was undertaken at two levels—woodlot unit and the woodlots themselves—using 16 different criteria.At the woodlot unit level, area and abundance indices of shade intolerant species in the tree layer could be used as synthetic criteria, while at the woodlot level the ecological value of the constituent units stand out as the first synthetic criterion. These results are compared with criteria proposed in the literature, and the use of multivariate analysis in ecological evaluation is briefly discussed.  相似文献   

14.
Southeastern Utah is a region of world-renowned red-rock sandstone formations, large tracts of federal public land, rural communities centered on agriculture and extractive industries, and is often at the epicenter of environmental protection efforts in the western United States. Environmental groups have proposed formal Wilderness designations for much of the regions public land—proposals that have been actively fought by rural community leaders who do not want large areas locked-up from traditional livelihood and recreational uses. The debate over wilderness designation in the region has been characterized in the media as one that is particularly contentious and polarizing. A survey of southeastern Utah residents was conducted in order to better understand this conflict. The survey focused on attitudes toward wilderness designation and management. We found that residents of southeastern Utah have negative attitudes towards the designation and management of Wilderness Study Areas. We propose that these attitudes should be carefully considered and engaged in future policy and management decisions. We suggest that negative opinions expressed by residents of southeastern Utah are not directed primarily at the concept of environmental protection but rather at the strong perception that these programs and initiatives have been carried out in a heavy-handed manner and dominated by outside influences that have overwhelmed local voices.  相似文献   

15.
Due to assimilation of recycled CO2 from litter decomposition and photosynthetic changes in carbon fractionation at low light levels, the foliage at the base of a forest is often more depleted in13C compared to that exposed to the atmosphere in either the canopy or in open clearings. This is referred to as the canopy effect. African research has indicated that these habitat differences in foliar 13C can be substantial enough to affect the carbon isotope ratios of resident fauna. Previous work documenting a 30-year chronology on moose teeth from Isle Royale National Park indicated a progressive depletion in13C and suggested that this could be due to forest regrowth following extensive burning. The present study examined the assumption implicit in this hypothesis that foliar 13C varies between open and closed boreal forest sites. I found a marginal canopy effect of 2 13C difference between upper canopy and ground flora for a forest in northwestern Ontario and an average difference of 1.2 in under- and mid-story vegetation between closed forests and open clear-cuts. Because of these small differences, the utility of carbon isotope analysis in quantifying temporally integrated exploitation of deforested habitats will be low for northern boreal locations. In denser forests, such as those in the tropics or western North American where the canopy effect can be expected to be much greater, 13C analysis may still offer some promise for determining selection by wildlife of disturbed habitats.  相似文献   

16.
Summary Effective communication concerning environmental issues can take a variety of forms. The following essay is offered as a metalogue, a piece of writing in which the writing itself illustrates the principles developed in the writing.International readers will be helped if they know that Jack Armstrong and Sergeant Preston are heroes of moralizing (and often jingoistic) radio dramas popular among children in the United States during the War years and that the Tom Mix Holster Set and the A-bomb Ring were premiums offered to children in boxes of cold cereal in the period after the War. These trivia illustrate the kinds of societal messages directed toward the generation of Americans who presumably will be running the country during the 1980s.The authors are a professor of Psychology and Ethology and a graduate student in International Development. Both attended Harvard University in the late 1950s and the University of California, Berkeley, in the early 1960s. Their autobiographical reflections have something to say about the motivation underlying the environmental movement and where these motivations are likely to lead in the near future.  相似文献   

17.
The evolution of sustainability   总被引:1,自引:0,他引:1  
Six separate but related strains of thought have emerged prominently since 1950 in discussions of such phenomena as the interrelationships among rates of population growth, resource use, and pressure on the environment. They are the ecological/carrying capacity root, the resources/environment root, the biosphere root, the critique of technology root, the no growth/slow growth root, and the ecodevelopment root.Each of these strains of thought was fully developed before the word sustainable itself was used. Many of the roots are based on fundamentally opposing assessments of the future of mankind. Many of the roots, such as the ecology/carrying capacity root, are based on physical concepts, and they exclude normative values. Others, such as the ecodevelopment root, include such values as equity, broad participation in governance, and decentralized government.When the word sustainability was first used in 1972 in the context of man's future, in a British book,Blueprint for Survival, normative concepts were prominent. This continued to be the case when the word was first used in 1974 in the United States to justify a no growth economy.Sustainability was first used in a United Nations document in 1978. Normative concepts, encapsulated in the term ecodevelopment, were prominent in the United Nations publications.After about 1978, the term sustainability began to be used not only in technological articles and reports but also in policy documents culminating in the use of the term in the report of the summit meeting of the Group of Seven in 1989.The roots of the term sustainability are so deeply embedded in fundamentally different concepts, each of which has valid claims to validity, that a search for a single definition seems futile. The existence of multiple meaning is tolerable if each analyst describes clearly what he means by sustainability.  相似文献   

18.
Professor Kathryn George's Use and Abuse Revisited does not contain an accurate assessment of my On Vegetarianism, Morality, and Science: A Counter Reply. I show that she has misrepresented my moral and empirical argumentation.  相似文献   

19.
Military installations provide important native habitat for songbirds, including many species that have experienced population declines in recent decades. As part of the Land Condition Trend Analysis (LCTA) program to monitor animal populations on military lands, we surveyed small (<250 g) breeding landbirds on 60 permanent plots on the Fort Riley Military Installation in northeastern Kansas from 1991 to 2002. During this period, species richness averaged 39.0 species (SE 0.9)/year and mean species richness per plot ranged from 3.6 species (SE=0.2)/plot (1999) to 7.5 species (SE=0.3)/plot (1992). Turnover (the appearance and disappearance of species on all plots from one year to the next) ranged from 5 species (2000–2001) to 16 species (1992–1993) and was driven primarily by turnover of woodland species. We developed an index of relative difference (C) to evaluate relative trends of local populations and found that 25 species declined, 15 species increased, and 7 did not change. Based on migration assemblages, more resident species (6 of 10) and more short-distant migrants (9 of 12) decreased than long-distance migrants (10 vs. 11). Our analysis of major vegetation communities on plots showed few changes in the quantity of habitats (grassland vs. woodlands) during the study. Our results indicate that Fort Riley provides important habitats for many landbirds, particularly those that require grasslands for breeding. Several species exhibited local declines when compared to the regional Breeding Bird Survey routes. We offer an approach that evaluates population changes of small landbirds and provides objective inputs for conservation directives. These can be adopted easily for use on military installations (that use LCTA), parks, and wildlife refuges that have data from annual breeding bird surveys.  相似文献   

20.
Biotechnology applied to traditional foodanimals raises ethical issues in three distinctcategories. First are a series of issues that arise inthe transformation of pigs, sheep, cattle and otherdomesticated farm animals for purposes that deviatesubstantially from food production, including forxenotransplantation or production of pharmaceuticals.Ethical analysis of these issues must draw upon theresources of medical ethics; categorizing them asagricultural biotechnologies is misleading. The secondseries of issues relate to animal welfare. Althoughone can stipulate a number of different philosophicalfoundations for the ethical assessment of welfare,most either converge on Bernard Rollins principle ofwelfare conservation (Rollin, 1995), or devolve intodebates over the ethical significance of animaltelos or species integrity. The principle of welfareconservation prohibits disfunctional geneticengineering of food animals, but would permit alteringanimals biological functions, especially when (as inmaking animals less susceptable to pain or suffering)do so improves an individual animals well being.Objections to precisely this last form of geneticengineering stress telos or species integrity asconstraints on modification of animals, and thisrepresents the third class of ethical issues. Most whohave formulated such arguments have failed to developcoherent positions, but the notion of species being,derived from the 19th century German tradition,presents a promising way to analyze the basis forresisting the transformation of animal natures.  相似文献   

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