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1.
In a previous article, Beschta et al. (Environ Manag 51(2):474–491, 2013) argue that grazing by large ungulates (both native and domestic) should be eliminated or greatly reduced on western public lands to reduce potential climate change impacts. The authors did not present a balanced synthesis of the scientific literature, and their publication is more of an opinion article. Their conclusions do not reflect the complexities associated with herbivore grazing. Because grazing is a complex ecological process, synthesis of the scientific literature can be a challenge. Legacy effects of uncontrolled grazing during the homestead era further complicate analysis of current grazing impacts. Interactions of climate change and grazing will depend on the specific situation. For example, increasing atmospheric CO2 and temperatures may increase accumulation of fine fuels (primarily grasses) and thus increase wildfire risk. Prescribed grazing by livestock is one of the few management tools available for reducing fine fuel accumulation. While there are certainly points on the landscape where herbivore impacts can be identified, there are also vast grazed areas where impacts are minimal. Broad scale reduction of domestic and wild herbivores to help native plant communities cope with climate change will be unnecessary because over the past 20–50 years land managers have actively sought to bring populations of native and domestic herbivores in balance with the potential of vegetation and soils. To cope with a changing climate, land managers will need access to all available vegetation management tools, including grazing.  相似文献   

2.
In response to Albrecht et al.’s (J Agric Environ Ethics 26(4):827–845, 2013) discussion on the ethics of assisted migration, we emphasize the issues of risk and scientific uncertainty as an inextricable part of a comprehensive ethical evaluation. Insisting on a separation of risk and ethical considerations, although arguably common in many policy contexts, is at best misguided and at worst damaging.  相似文献   

3.
Protection of native aquatic plants is an important proenvironmental behavior, because plant loss coupled with nutrient loading can produce changes in lake ecosystems. Removal of aquatic plants by lakeshore property owners is a diffuse behavior that may lead to cumulative impacts on lake ecosystems. This class of behavior is challenging to manage because collective impacts are not obvious to the actors. This paper distinguishes positive and negative beliefs about aquatic plants, in models derived from norm activation theory (Schwartz, Adv Exp Soc Psychol 10:221–279, 1977) and the theory of reasoned action (Fishbein and Ajzen, Belief, attitude, intention, and behavior: an introduction to theory and research, Addison-Wesley, Boston 1975), to examine protection of native aquatic plants by Minnesota lakeshore property owners. We clarify how positive and negative evaluations of native aquatic plants affect protection or removal of these plants. Results are based on a mail survey (n = 3,115). Results suggest that positive evaluations of aquatic plants (i.e., as valuable to lake ecology) may not connect with the global attitudes and behavioral intentions that direct plant protection or removal. Lakeshore property owners’ behavior related to aquatic plants may be driven more by tangible personal benefits derived from accessible, carefully managed lakeshore than intentional action taken to sustain lake ecosystems. The limited connection of positive evaluations of aquatic plants to global attitudes and behavioral intentions may reflect either lack of knowledge of what actions are needed to protect lake health and/or unwillingness to lose perceived benefits derived from lakeshore property.  相似文献   

4.
As federal agencies and businesses rely more on cyber infrastructure, they are increasingly vulnerable to cyber attacks that can cause damages disproportionate to the sophistication and cost to launch the attack. In response, regulatory authorities call for focusing attention on enhancing infrastructure resilience. For example, in the USA, President Obama issued an Executive Order and policy directives focusing on improving the resilience and security of cyber infrastructure to a wide range of cyber threats. Despite the national and international importance, resilience metrics to inform management decisions are still in the early stages of development. We apply the resilience matrix framework developed by Linkov et al. (Environ Sci Technol 47:10108–10110, 2013) to develop and organize effective resilience metrics for cyber systems. These metrics link national policy goals to specific system measures, such that resource allocation decisions can be translated into actionable interventions and investments. In this paper, a number of metrics have been identified and assessed using quantitative and qualitative measures found in the literature. We have proposed a generic approach and could integrate actual data, technical judgment, and literature-based measures to assess system resilience across physical, information, cognitive, and social domains.  相似文献   

5.
Tom et al. (Environ Syst Decis 1–12, 2015) compared the energy requirements, water footprint, and greenhouse gas emissions of diet regimens recently recommended by the US Department of Agriculture. This editorial comments on a number of challenges related to the use of the results of life-cycle assessment studies to quantify the environmental impacts of dietary shifts.  相似文献   

6.
The concept of animal welfare in confinement agriculture—and an ethical theory based upon this concept—necessitates an idea of what kind of being it is that fares well and what “well” is for this being. This double-question is at the heart of understanding and adequately defining welfare as qualitatively embedded in the experiencing subject. The notion of telos derives (philosophically) from Aristotle and is a way of accounting for the good life of an animal from the unique speciesness of the animal in question. The first part of the article will address the contemporary philosophical and ethical analysis of animals based upon this Aristotelian idea (Rollin in Animal rights and human morality (1st ed. 1981). Prometheus Books, New York, 2006b). Telos is here employed to illustrate the dimensions of what matters in welfare assessment and ethical evaluation. The second half of the article addresses some of the welfare problems in modern animal agriculture and how they relate to the telos concept. Two main examples are dealt with: Boredom (Wemelsfelder in Mental health and well-being in animals. Blackwell Publishing, Oxford, 2005) is argued as being the suffering of choicelessness in animals that are inherently beings that choose—and loneliness is the suffering of social isolation in animals for whom standing in active relations to others is part of what they are.  相似文献   

7.
The recognition of the significance of the residential environment in contributing to non-point source (NPS) pollution and the inherently dispersed nature of NPS pollution itself that presents significant challenges to effective regulation has led to the creation and dissemination of best management practices (BMPs) that can reduce the impacts of NPS pollution (Environmental Protection Agency US, Protecting water quality from urban runoff, http://www.epa.gov/npdes/pubs/nps_urban-facts_final.pdf, 2003). However, very few studies have examined the factors that influence the adoption of BMPs by residential homeowners, despite the fact that residential environments have been identified as one of the most significant contributors to NPS pollution. Given this need, the purpose of this project was to explore how demographic and knowledge-based factors predict adoption of residential BMPs in an urbanizing watershed in Northern Illinois using statistical analyses of survey data collected as part of a watershed planning process. The findings indicate that broad knowledge of BMPs is the strongest predictor of use for a specific BMP. Knowledge of BMPs is strongly correlated with their use, which reinforces the need for educational programs, even among those assumed to be knowledgeable about BMPs.  相似文献   

8.
This work is devoted to some methodological developments on information fusion in presence of uncertainty and their application in the frame of the BEMUSE Programme. In nuclear safety studies, different uncertainty analyses using different codes and implying different experts are generally performed. It is then useful to define formal methods to combine all these information sources in order to improve the reliability of the expertise process and especially to detect possible conflicts (if any) between the sources. Starting from the IRSN methodology already introduced in Destercke and Chojnacki (Nucl Eng Des 238(9):2484–2493, 2008), this paper presents a more convenient reformulation of its construction to allow its use by engineers. It is then applied to analyse the results coming from the BEMUSE Programme.  相似文献   

9.
Government priorities on provincial Nutrient Management Planning (NMP) programs include improving the program effectiveness for environmental quality protection, and promoting more widespread adoption. Understanding the effect of NMP on both crop yield and key water-quality parameters in agricultural watersheds requires a comprehensive evaluation that takes into consideration important NMP attributes and location-specific farming conditions. This study applied the Soil and Water Assessment Tool (SWAT) to investigate the effects of crop and rotation sequence, tillage type, and nutrient N application rate on crop yield and the associated groundwater ${\text{NO}_{3}}^{ - } {\text{-N }}$ leaching and sediment loss. The SWAT model was applied to the Thomas Brook Watershed, located in the most intensively managed agricultural region of Nova Scotia, Canada. Cropping systems evaluated included seven fertilizer application rates and two tillage systems (i.e., conventional tillage and no-till). The analysis reflected cropping systems commonly managed by farmers in the Annapolis Valley region, including grain corn-based and potato-based cropping systems, and a vegetable-horticulture system. ANOVA models were developed and used to assess the effects of crop management choices on crop yield and two water-quality parameters (i.e., ${\text{NO}_{3}}^{ - } {\text{-N }}$ leaching and sediment loading). Results suggest that existing recommended N-fertilizer rate can be reduced by 10–25 %, for grain crop production, to significantly lower ${\text{NO}_{3}}^{ - } {\text{-N }}$ leaching (P > 0.05) while optimizing the crop yield. The analysis identified the nutrient N rates in combination with specific crops and rotation systems that can be used to manage ${\text{NO}_{3}}^{ - } {\text{-N }}$ leaching while balancing impacts on crop yields within the watershed.  相似文献   

10.
Over the last three decades, livestock exclosure research has emerged as a preferred method to evaluate the ecology of riparian ecosystems and their susceptibility to livestock impacts. This research has addressed the effects of livestock exclusion on many characteristics of riparian ecosystems, including vegetation, aquatic and terrestrial animals, and geomorphology. This paper reviews, critiques, and provides recommendations for the improvement of riparian livestock exclosure research. Exclosure-based research has left considerable scientific uncertainty due to popularization of relatively few studies, weak study designs, a poor understanding of the scales and mechanisms of ecosystem recovery, and selective, agenda-laden literature reviews advocating for or against public lands livestock grazing. Exclosures are often too small (<50 ha) and improperly placed to accurately measure the responses of aquatic organisms or geomorphic processes to livestock removal. Depending upon the site conditions when and where livestock exclosures are established, postexclusion dynamics may vary considerably. Systems can recover quickly and predictably with livestock removal (the “rubber band” model), fail to recover due to changes in system structure or function (the “Humpty Dumpty” model), or recover slowly and remain more sensitive to livestock impacts than they were before grazing was initiated (the “broken leg” model). Several initial ideas for strengthening the scientific basis for livestock exclosure research are presented: (1) incorporation of meta-analyses and critical reviews. (2) use of restoration ecology as a unifying conceptual framework; (3) development of long-term research programs; (4) improved exclosure placement/design; and (5) a stronger commitment to collection of pretreatment data.  相似文献   

11.
Insect neurobiology and cognition are most fully understood through studies on European honeybees (Apis mellifera ssp.; Hymenoptera: Apidae). Karl von Frisch (1886?C1982) became a Nobel Laureate in Medicine and Physiology (1973) for his pioneering research on honeybee behaviour, learning and social communication (von Frisch Tanzsprache und Orientierung der Bienen. Springer, Berlin,1965, The dance language and orientation of bees. Harvard University Press, Cambridge,1967). His enduring work stimulated numerous prominent scientists, including Martin Lindauer (1918?C2008) who was mentor to R. M., and whose nomination provided P. K. with a DAAD fellowship to work with his team in the Institut für Neurobiologie of the Freie Universit?t Berlin in 1994. Honeybees are the most important managed pollinators of crop plants and responsible for estimated billions of dollars worth of food production annually. Although these insects make excellent subjects for basic research, understanding their biology often has immediate practical implications. Honeybees, and beekeeping, around the world appear to be facing serious problems to such a grave extent that the popular media are full of stories about their demise and the potential consequences to human food security. How honeybees perceive their world, especially the flowers they pollinate, and how they react to stresses in their environments (management, pathogens, parasites, pesticides, pollutants and landscape changes) are closely interlinked. Therefore, the relationships between basic and applied research become of immediate importance and may lead to a better handling of the ecological conditions under which honeybees perform their economically important contribution to the balance of nature.  相似文献   

12.
Humans are now virtually found everywhere in the world. They changed the global nitrogen and phosphate cycles, create light pollution and affect the soundscapes, even in remote wilderness areas. The destruction of the earth and its original habitat is found on land, in the ocean and now, in the atmosphere. Of note are the big impacts from the many small contaminations (e.g., Ott in Sound truth and corporate myths: the legacy of the Exxon Valdez oil spill. Dragonfly Sisters Press, Cordova, 2005). The global magnitude of this man-made impact is virtually unprecedented in human history. Indigenous populations lived within earth??s carrying capacity for easily over 10,000?years, and they never caused such global impacts. It is obvious from most metrics that these problems steeply increased during the last 50?years. This suggests that global procedures and policies, and arguably driven by western industrialized countries, cultures and institutions setting the global framework, are affecting sustainability in dramatic ways. Based on documented and public sources, here I show the brief history, European thought, its global expansion, successes and global sustainability failures. There is an inherent and widely acknowledged conflict between growing the gross domestic product (GDP) and biodiversity, and when considering that we all live on one finite world. Works by Daly, Diamond, Flannery, Shtilmark, Leopold and many others make that already widely clear. Our land- and seascapes are currently overcommitted. With an increase of the human population of over 9?billion people in the next 100?years??likely earlier??we are at the very brink of biodiversity and humanity, and of the earth as we know it. Business as usual, and purely technical and industrial environmental efforts will not help us, and instead, we need a sustainability reform of institutions, education, funding schemes, cultures and society if we want to keep striving, or at least maintain the status quo.  相似文献   

13.
The introduction of national parks in areas where existing authorities have traditionally been responsible for developing policies, preparing plans and making decisions on development proposals, can be a threat to longstanding interests. This paper explores this problem by examining the struggle for control of planning in one of Scotland's first national parks, the Cairngorms. Recent research (McCarthy et al., 2002 McCarthy J Lloyd G Illsley B (2002) National parks in Scotland: balancing environment and economy Research briefing European Planning Studies 10 (5) pp. 665–670 [Web of Science ®] [Google Scholar]) has established the policy context for this investigation. Informed by research focusing on the consultation process which led to the establishment of the national park, this paper analyzes how alternative approaches to the allocation of planning powers were captured in competing storylines, around which polarized coalitions of interest formed. Opening such insights into the considerations that shape institutional design—a combination of contested problem framing and straightforward political struggles over the locus of regulatory power—starkly reveals the challenges to the new park authority as it seeks to establish consensus between conflicting interests.  相似文献   

14.
Streamside vegetation frequently regenerates faster than upland vegetation following wildland fire and contributes to the recovery of riparian and stream ecosystems. Limited data are available, however, on the post‐fire growth of riparian species and the influence of herbivory on regeneration. To determine post‐fire regrowth of riparian vegetation, height, crown area, crown volume, and browse levels were measured for key riparian shrub species in streamside burned and unburned plots along second‐order streams in western Wyoming. Shrubs in the burned plots were subject to high levels of browse ‐ up to 84 percent of the leaders were browsed ‐ by native ungulates in 2002, the second post‐fire year (September 2001 to September 2002). In summer 2003, the burned watershed was also grazed by livestock, resulting in increased browse levels and decreased shrub heights for several species. In the third post‐fire year, September 2002 to September 2003, four of the six most common species showed no increase in crown area or crown volume, indicating that the combination of native ungulate and cattle browsing suppressed their growth. Potential impacts of grazing on post‐fire recovery of stream and riparian ecosystems are discussed.  相似文献   

15.
The European Landscape Convention (2000) obligates European Union countries to identify and implement landscape quality objectives (LQOs) understood as the specification of public expectations and preferences concerning the landscape of a given area, expressed by competent public authorities. The convention emphasizes the important role of local community representatives in this field. In Poland, the implementation of the LQO concept was first undertaken in two regions with radically different landscape characteristics: (1) the West Polesie Biosphere Reserve and (2) the selected protected areas of the Roztocze–Solska Forest, nominated to the rank of a biosphere reserve. The first stage of the presented study was the recognition of public opinion on the quality of key features of landscape, based on a questionnaire (n = 470). The primary objective of the study was to provide an answer to the following questions: (1) Whether similar social expectations regarding landscape quality exist in spite of radically different landscape characteristics of the regions investigated (landscape quality is understood as spatial arrangement, scenic beauty, and lack of environmental pollution); (2) which landscape features are considered to be most preservation worthy by the representatives of both local communities; and (3) What processes or development impacts pose the greatest threat to the landscape quality of both regions according to the public opinion? The conducted comparative assessment revealed that it is possible to define a set of features fundamental to the quality of both areas and that representatives of local communities pointed out the same threats to the natural and cultural values of both regions investigated.  相似文献   

16.
The wildland–urban interface (WUI) is the region where development meets and intermingles with wildlands. The WUI has an elevated fire risk due to the proximity of development and residents to wildlands with natural wildfire regimes. Existing methods of delineating WUI are typically applied over a large region, use proxies for risk, and do not consider site-specific fire hazard drivers. While these models are appropriate for federal and provincial risk management, municipal managers require models intended for smaller regions. The model developed here uses the Burn-P3 fire behavior model to model WUI from local fire susceptibility (FS) in two study communities. Forest fuel code (FFC) maps for the study communities were modified using remote sensing data to produce detailed forest edges, including ladder fuels, update data currency, and add buildings and roads. The modified FFC maps used in Burn-P3 produced bimodal FS distributions for each community. The WUI in these communities was delineated as areas within community bounds where FS was greater than or equal to ?1 SD from the mean FS value ( ${\text{WUI}} = {\text{FS}} \geqslant - 1 \, [\bar \chi - \sigma ]$ ), which fell in the trough of the bimodal distribution. The WUI so delineated conformed to the definition of WUI. This model extends WUI modeling for broader risk management initiatives for municipal management of risk, as it (a) considers site-specific drivers of fire behavior; (b) models risk, represented by WUI, specific to a community; and, (c) does not use proxies for risk.  相似文献   

17.
Uncertainties inherent in fisheries motivate a precautionary approach to management, meaning an approach specifically intended to avoid bad outcomes. Stochastic dynamic optimization models, which have been in the fisheries literature for decades, provide a framework for decision making when uncertain outcomes have known probabilities. However, most such models incorporate population dynamics models for which the parameters are assumed known. In this paper, we apply a robust optimization approach to capture a form of uncertainty nearly universal in fisheries, uncertainty regarding the values of model parameters. Our approach, developed by Nilim and El Ghaoui (Oper Res 53(5):780–798, 2005), establishes bounds on parameter values based on the available data and the degree of precaution that the decision maker chooses. To demonstrate the applicability of the method to fisheries management problems, we use a simple example, the Skeena River sockeye salmon fishery. We show that robust optimization offers a structured and computationally tractable approach to formulating precautionary harvest policies. Moreover, as better information about the resource becomes available, less conservative management is possible without reducing the level of precaution.  相似文献   

18.
In the western United States, livestock grazing often co-exists with recreation, cultural resource management and biodiversity protection on federal and state protected rangelands as well as on many local government open space areas. While the value of livestock grazing for managing rangeland vegetation to reduce fire fuel loads and improve wildlife habitat is increasingly recognized by resource management professionals, public concerns, and conflict between recreationist and livestock have led to reductions in public land grazing. Traditional public input methods yield a constrained picture of people’s attitudes toward cows and public land grazing. Public meetings, hearings, and surveys, the most commonly used mechanisms for public land managers to solicit public opinion, tend to foster participation of organized special interests or, in the case of surveys, focus on a specific topic. General public input is limited. This study explored the use of personal photography in social media to gain insight into public perceptions of livestock grazing in public spaces. Key findings of this study include that many recreationist in grazed San Francisco Bay Area parks shared views, interests, and concerns about cows and grazing on the photo-sharing website, FlickrTM that seldom show up at a public meeting or in surveys. Results suggest that social media analysis can help develop a more nuanced understanding of public viewpoints useful in making decisions and creating outreach and education programs for public grazing lands. This study demonstrates that using such media can be useful in gaining an understanding of public concerns about natural resource management.  相似文献   

19.
Climate change affects public land ecosystems and services throughout the American West and these effects are projected to intensify. Even if greenhouse gas emissions are reduced, adaptation strategies for public lands are needed to reduce anthropogenic stressors of terrestrial and aquatic ecosystems and to help native species and ecosystems survive in an altered environment. Historical and contemporary livestock production—the most widespread and long-running commercial use of public lands—can alter vegetation, soils, hydrology, and wildlife species composition and abundances in ways that exacerbate the effects of climate change on these resources. Excess abundance of native ungulates (e.g., deer or elk) and feral horses and burros add to these impacts. Although many of these consequences have been studied for decades, the ongoing and impending effects of ungulates in a changing climate require new management strategies for limiting their threats to the long-term supply of ecosystem services on public lands. Removing or reducing livestock across large areas of public land would alleviate a widely recognized and long-term stressor and make these lands less susceptible to the effects of climate change. Where livestock use continues, or where significant densities of wild or feral ungulates occur, management should carefully document the ecological, social, and economic consequences (both costs and benefits) to better ensure management that minimizes ungulate impacts to plant and animal communities, soils, and water resources. Reestablishing apex predators in large, contiguous areas of public land may help mitigate any adverse ecological effects of wild ungulates.  相似文献   

20.
Fire and grazing are common management schemes of grasslands globally and are potential drivers of reptilian and amphibian (herpetofauna) metacommunity dynamics. Few studies have assessed the impacts of fire and cattle grazing on herpetofauna assemblages in grasslands. A patch-burn grazing study at Osage Prairie, MO, USA in 2011–2012 created landscape patches with treatments of grazing, fire, and such legacies. Response variables were measured before and after the application of treatments, and I used robust-design occupancy modeling to estimate patch occupancy and detection rate within patches, and recolonization and extinction (i.e., dispersal) across patches. I conducted redundancy analysis and a permuted multivariate analysis of variance to determine if patch type and the associated environmental factors explained herpetofauna assemblage. Estimates for reptiles indicate that occupancy was seasonally constant in Control patches (ψ ~ 0.5), but declined to ψ ~ 0.15 in patches following the applications of fire and grazing. Local extinctions for reptiles were higher in patches with fire or light grazing (ε ~ 0.7) compared to the controls. For the riparian herpetofaunal community, patch type and grass height were important predictors of abundance; further, the turtles, lizards, snakes, and adult amphibians used different patch types. The aquatic amphibian community was predicted by watershed and in-stream characteristics, irrespective of fire or grazing. The varying responses from taxonomic groups demonstrate habitat partitioning across multiple patch types undergoing fire, cattle grazing, and legacy effects. Prairies will need an array of patch types to accommodate multiple herpetofauna species.  相似文献   

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