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1.
Adaptive management (AM) is the process of implementing land management activities in incremental steps and evaluating whether desired outcomes are being achieved at each step. If conditions deviate substantially from predictions, management activities are adjusted to achieve the desired outcomes. Thus, AM is a kind of monitoring, an activity that land management agencies have done poorly for the most part, at least with respect to ground-based monitoring. Will they do better in the future? We doubt it unless costs, personnel, and future commitment are seriously addressed. Because ecosystem responses to management impacts can ripple into the distant future, monitoring programs that address only the near future (e.g., 10–20 years), are probably unreliable for making statements about resource conditions in the distant future. We give examples of this. Feedback loops between ecosystem response and adjustment of management actions are often broken, and therefore AM again fails. Successful ground-based monitoring must address these and other points that agencies commonly ignore. As part of the solution, publics distrustful of agency activities should be included in any monitoring program.  相似文献   

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Approximately 37% of forestlands in the conterminous United States are publicly owned; they represent a substantial area of potential carbon sequestration in US forests and in forest products. However, large areas of public forestlands traditionally have been less intensively inventoried than privately owned forests. Thus, less information is available about their role as carbon sinks. We present estimates of carbon budgets on public forestlands of the 48 conterminous states, along with a discussion of the assumptions necessary to make such estimates. The forest carbon budget simulation model, FORCARB2, makes estimates for US forests primarily based on inventory data. We discuss methods to develop consistent carbon budget estimates from inventory data at varying levels of detail. Total carbon stored on public forestlands in the conterminous US increased from 16.3 Gt in 1953 to the present total of 19.5 Gt, while area increased from 87.1 million hactares to 92.1 million hactares. At the same time the proportion of carbon on public forestlands relative to all forests increased from 35% to 37%. Projections for the next 40 years depend on scenarios of management influences on growth and harvest.This article was written and prepared by US Government employees on official time, and it is therefore in the public domain and not subject to copyright.  相似文献   

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Increased salinity in spawning and nursery grounds in the Savannah River estuary was cited as the primary cause of a 97% decrease in adult striped bass (Morone saxatilis) and a concomitant 96% decrease in striped bass egg production. Restoration efforts focused on environmental remediation and stock enhancement have resulted in restored salinity patterns and increased egg and adult abundances. However, future water needs or harbor development may preclude further recovery by reducing freshwater inflow or increasing salinity intrusion. To assess the effect of potential changes in the salinity regime, we developed models relating discharge, tidal phase, and salinity to striped bass egg and early larval survival and re-cast these in a quantitative Bayesian belief network. The model indicated that a small upstream shift (≤1.67 km) in the salinity regime would have the least impact on striped bass early life history survival, whereas shifts >1.67 km would have progressively larger impacts, with a 8.33-km shift potentially reducing our estimated survival probability by >28%. Such an impact could have cumulative and long-term detrimental effects on the recovery of the Savannah River striped bass population. The available salinity data were collected during average and low flows, so our model represents some typical and some extreme conditions during a striped bass spawning season. Our model is a relatively simplistic, “first-order” attempt at evaluating potential effects of changes in the Savannah River estuarine salinity regime and points to areas of concern and potential future research.  相似文献   

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Regulating groundwater in the Eastern United States (U.S.), particularly transboundary aquifers between states, is a challenge given the patchwork quilt of common law, statutory frameworks, and agency rules. Such regulation is made more challenging by the need for better quantification of pumping and use. These dynamics are exemplified through several case studies, including the first ever U.S. Supreme Court case related to groundwater withdrawals (set in the Eastern U.S.). As dynamics such as expanded irrigation, population increases, and ecological considerations influence groundwater use across the Eastern U.S., water use will continue to be an important driver for economic activity and interaction within and between states. To effectively regulate transboundary aquifers, governance solutions must incorporate current science into decision making and be implemented at local, state, regional, and federal scales.  相似文献   

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Abstract: This paper examines the use of climate forecasting in water management in Brazil and the United States (U.S.). Specifically, it seeks to understand how different institutional arrangements shape the willingness and ability of water managers to incorporate technoscience, especially seasonal climate forecasting (SCF), in their decision‐making process. It argues that among the many factors shaping the willingness of water managers to use SCF, institutional design and change is critical to explain different patterns in Brazil and the U.S. Moreover, factors related to individual flexibility, discretion, and accountability also affect the ability of managers to use climate information in water management. This paper finds that while water managers in the U.S operate in a mostly fragmented and risk‐averse system – which constrains the adoption of innovation – decision makers in Brazil can afford more flexibility to introduce new decision tools as a result of widespread water management reforms initiated in the 1990s.  相似文献   

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The concept of resilience is now frequently invoked by natural resource agencies in the US. This reflects growing trends within ecology, conservation biology, and other disciplines acknowledging that social–ecological systems require management approaches recognizing their complexity. In this paper, we examine the concept of resilience and the manner in which some legal and regulatory frameworks governing federal natural resource agencies have difficulty accommodating it. We then use the U.S. Forest Service’s employment of resilience as an illustration of the challenges ahead.  相似文献   

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In the prior‐appropriation water rights regimes that prevail in the arid western United States, claims to annually variable surface water flows are fulfilled based on the order of their establishment. The two‐step process used to establish an appropriative water right in all 17 conterminous western states creates a temporary phase, or conditional water right, which has a priority date but no actual water use. We provide a review of the legal basis for these conditional water rights and demonstrate the potential uncertainty they introduce to current water users. We then present a complete census of conditional water rights in Colorado, including their amounts, ages, and uses. At the end of 2012 there were a large number of conditional water rights in Colorado (some over 90 years old) equal to 61% of the perfected water rights. Many of the controversial conditional water rights in Colorado have been associated with unconventional oil production in the northwestern portion of the state; however, conditional water rights are ubiquitous across the state and across many use types. In several basins, their existence can introduce uncertainty to some of the most senior water rights holders. Nevertheless, in most of the state, the effects of conditional water rights are restricted to a relatively junior class of water users. This work quantifies for the first time the result, in one state, of a peculiar aspect of water law common across all western prior‐appropriation states.  相似文献   

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In the process of implementing EU policy, Member States sometimes introduce new policy instruments in cases where this is not obligatory. To better understand this phenomenon, this paper reviews three cases in which new instruments emerged and develops a methodology to trace back the influence of EU Directives on instrument choice. The method is illustrated by a narrative of the emergence of new management planning instruments during the implementation of the EU Habitats Directive in three EU Member States: Finland, Hungary and the Netherlands. Three key features of a policy instrument are defined, namely, its authoritative force, action content and governance design. These are used to measure the contribution of the Habitats Directive compared to other potential explanatory causes for the emergence of the new policy instrument. In all three reviewed countries a nested causal relationship between the Habitats Directive and the introduction of the new policy instrument is identified. Based on the relative contribution of the Habitats Directive to the emergence of the new instrument a distinction is made whether the Directive acted as a cause, catalyst or if conjunction occurred.  相似文献   

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Abstract: A public opinion survey was carried out in Montana to ascertain if the public identifies a level of benthic (bottom‐attached) river and stream algae that is undesirable for recreation. The survey had two parts; an On‐River survey and a By‐Mail survey. The On‐River survey was conducted via 44 trips randomly scheduled throughout the state during which recreators were interviewed in‐person at the stream. Selection of stream segments and survey dates/times was based on known, statewide recreational use patterns. By‐Mail survey forms were sent to 2,000 individuals randomly selected from Montana’s Centralized Voter File (CVF) available from the Montana Secretary of State. The CVF was current through 2004 and represented over 85% of the state’s eligible voting population. In both surveys, eight randomly ordered photographs depicting varying levels of stream benthic algae were presented, and participants were asked if the algae level shown was desirable or undesirable for recreation. Survey form design, selection of photographs, and pretesting followed acceptable protocols that limited unintentional bias through survey execution. There were 433 returned forms (389 complete) for the By‐Mail survey, while the On‐River survey documented 563 interviews. In both surveys, as benthic algal chlorophyll a (Chl a) levels increased, desirability for recreation decreased. (Other measures of benthic algae biomass are presented as well.) For the public majority, mean benthic Chl a levels ≥200 mg/m2 were determined to be undesirable for recreation, whereas mean levels ≤150 mg Chl a/m2 were found to be desirable. Error rates were within the survey’s statistical design criteria (≤5%). The largest potential error source was nonresponse in the By‐Mail survey; however, the population represented by nonrespondents would have to exhibit profoundly different perceptions of river and stream algae to meaningfully alter the results. Results support earlier work in the literature suggesting 150 mg Chl a/m2 represents a benthic algae nuisance threshold.  相似文献   

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This review presents first ever literature survey on historical development of farm animal welfare indicators and assessment in the Danube region. This area, encompassing European Eastern countries and the Balkans, is to a large extent heterogeneous in terms of culture and language. However, international (English) publications were disproportionally small compared to the amount of research institutions and animal welfare activities present in the region. Therefore, the authors aimed at investigating the published literature, focusing on country level and on native languages. Data were collected for the 1980–2015 period referring to scientific papers published in international and national journals, papers and abstracts in proceedings of the international and national conferences, reviews, monographs, short communications, Ph.D., Master and Graduation theses. Welfare assessment of all farm animal species was observed including fish. Over 180 papers were in line with the preselected index. Data collected showed that publishing dynamics grew rapidly towards the last decade. Most of the studies were focused on animal welfare indicators such as stress, injuries and mutilations, behaviour, body condition and management practices. Cattle, chickens, pigs and sheep were the predominant species investigated. The study revealed that experts from the region were greatly involved in the studies of animal welfare indicators and assessment, contributing to development of the currently most widely used animal welfare assessment protocols, thus having an important role in animal welfare research and protection.  相似文献   

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In Ethiopia, climate change and associated risks are expected to have serious consequences for agriculture and food security. This in turn will seriously impact on the welfare of the people, particularly the rural farmers whose main livelihood depends on rain-fed agriculture. The level of impacts will mainly depend on the awareness and the level of adaptation in response to the changing climate. It is thus important to understand the role of the different factors that influence farmers’ adaptation to ensure the development of appropriate policy measures and the design of successful development projects. This study examines farmers’ perception of change in climatic attributes and the factors that influence farmers’ choice of adaptation measures to climate change and variability. The estimated results from the climate change adaptation models indicate that level of education, age and wealth of the head of the household; access to credit and agricultural services; information on climate, and temperature all influence farmers’ choices of adaptation. Moreover, lack of information on adaptation measures and lack of finance are seen as the main factors inhibiting adaptation to climate change. These conclusions were obtained with a Multinomial logit model, employing the results from a survey of 400 smallholder farmers in three districts in Tigray, northern Ethiopian.  相似文献   

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Nature-based tourism and recreation within and close to protected areas may have negative environmental impacts on biodiversity due to urban development, landscape fragmentation, and increased disturbance. We conducted a 3-year study of disturbances of birds induced by nature-based tourism over a recreational gradient in the Pallas-Yllästunturi National Park and its surroundings in northern Finland. Bird assemblages were studied in highly disturbed areas close to the park (a ski resort, villages, and accommodation areas) and in campfire sites, along hiking routes (recreational areas) and in a forest (control area) within the park. Compared with the forest, the disturbed urbanized areas had higher abundances of human-associated species, corvid species, cavity and building nesters, and edge species. The abundances of managed forest species were higher in campfire sites than in the forest. Hiking trails and campfire sites did not have a negative impact on open-nesting bird species. The most likely reason for this outcome is that most campfire sites were situated at forest edges; this species group prefers managed forests and forest edge as a breeding habitat. The abundances of virgin forest species did not differ among the areas studied. The results of the study suggest that the current recreation pressure has not caused substantial changes in the forest bird communities within the National Park. We suggest that the abundances of urban exploiter species could be used as indicators to monitor the level and changes of urbanization and recreational pressure at tourist destinations.  相似文献   

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In recent years, researchers and policy makers have recognized that nontimber forest products (NTFPs) extracted from forests by rural people can make a significant contribution to their well-being and to the local economy. This study presents and discusses data that describe the contribution of NTFPs to cash income in the dry deciduous forests of Orissa and Jharkhand, India. In its focus on cash income, this study sheds light on how the sale of NTFPs and products that use NTFPs as inputs contribute to the rural economy. From analysis of a unique data set that was collected over the course of a year, the study finds that the contribution of NTFPs to cash income varies across ecological settings, seasons, income level, and caste. Such variation should inform where and when to apply NTFP forest access and management policies.  相似文献   

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Many countries are confronting climate change that threatens agricultural production and farmers’ lives. Farmers’ perceived risks of climate change and factors influencing those perceived risks are critical to their adaptive behavior and well-planned adaptation strategies. However, there is limited understanding of these issues. In this paper, we attempt to quantitatively measure farmers’ perceived risks of climate change and explore the influences of risk experience, information, belief in climate change, and trust in public adaptation to those perceived risks. Data are from structured interviews with 598 farmers in the Mekong Delta. The study shows that perceived risks to production, physical health, and income dimensions receive greater priority while farmers pay less attention to risks to happiness and social relationships. Experiences of the events that can be attributed to climate change increase farmers’ perceived risks. Information variables can increase or decrease perceived risks, depending on the sources of information. Farmers who believe that climate change is actually happening and influencing their family’s lives, perceive higher risks in most dimensions. Farmers who think that climate change is not their concern but the government’s, perceive lower risks to physical health, finance, and production. As to trust in public adaptation, farmers who believe that public adaptive measures are well co-ordinated, perceive lower risks to production and psychology. Interestingly, those who believe that the disaster warning system is working well, perceive higher risks to finance, production, and social relationships. Further attention is suggested for the quality, timing, and channels of information about climate change and adaptation.  相似文献   

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This article presents a critical reflection on the theory and practice of social sustainability in the built environment, identifies areas of agreement and disagreement, explores theoretical and conceptual gaps and challenges, and suggests practical implications for future research and urban policy. It argues that despite revisionist approaches which challenge the tripartite structure of sustainable development, social dimension of sustainability remains an essential valid pillar. Utilising a qualitative meta-analysis methodology for undertaking critical analysis of previous research and publications on the topic, key themes of theory and practice of social sustainability are identified and critically examined. Accordingly, 10 key formative characteristics of social sustainability and their research and policy implications are introduced. The article concludes with institutional observations for policy-makers to achieve greater success in addressing largely underestimated dimensions of social sustainability in urban settings.  相似文献   

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/ The Itapiranga Sustainable Logging Plan provides an example of how Brazil's licensing system functions for logging companies in the state of Amazonas. Two questions need to be dealt with: "How sustainable can logging in the Amazon be?" and "What and how effective are existing legal mechanisms to deal with logging projects?" The environmental impact assessment (EIA) and environmental impact statement (EIS, known as the RIMA in Brazil), present relatively detailed accounts of biodiversity and the need to adopt conservation strategies to protect it. However, social and health impacts are only superficially addressed. The economic sustainability of the operation over multiple cycles is not demonstrated. The multidisciplinary teams responsible for the EIA and EIS (RIMA) reports are hired by the project proponent, an arrangement inherently carrying the risk of biasing the result. Logging reduces biodiversity, releases greenhouse gases and inflicts social and health costs. These impacts reduce the ability of Amazonian forests to provide environmental services and to supply food and livelihood security to local populations. The reports inflate positive effects such as employment: the estimated number of jobs was cut by more than half in a revision made after the EIA and EIS (RIMA) had been approved. Not only do the reports need to be more realistic in assessing both positive and negative consequences of proposed projects, but better means are needed to ensure that promised mitigatory measures are enforced in practice. Many of the lessons that can be drawn from the Itapiranga Plan are not unique to logging projects and apply to licensing of development activites generally in Brazil and elsewhere.  相似文献   

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