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1.
Agroforestry systems are fundamental features of the rural landscape of the Indian state of Kerala. Yet these mixed species systems are increasingly being replaced by monocultures. This paper explores how public policies on land tenure, agriculture, forestry and tree growing on private lands have interacted with farmer preferences in shaping land use dynamics and agroforestry practices. It argues that not only is there no specific policy for agroforestry in Kerala, but also that the existing sectoral policies of land tenure, agriculture, and forestry contributed to promoting plantation crops, even among marginal farmers. Forest policies, which impose restrictions on timber extraction from farmers’ fields under the garb of protecting natural forests, have often acted as a disincentive to maintaining tree-based mixed production systems on farmlands. The paper argues that public policies interact with farmers’ preferences in determining land use practices.  相似文献   

2.
In this paper we hypothesize that land use change can be induced by non-linearities and thresholds in production systems that impact farmers' decision making. Tradeoffs between environmental and economic indicators is a useful way to represent dynamic properties of agricultural systems. The Tradeoff Analysis (TOA) System is software designed to implement the integrated analysis of tradeoffs in agricultural systems. The TOA methodology is based on spatially explicit econometric simulation models linked to spatially referenced bio-physical simulation models to simulate land use and input decisions. The methodology has been applied for the potato-pasture production system in the Ecuadorian Andes. The land use change literature often describes non-linearity in land use change as a result of sudden changes in the political (e.g. new agricultural policies) or environmental setting (e.g. earthquakes). However, less attention has been paid to the non-linearities in production systems and their consequences for land use change. In this paper, we use the TOA system to study agricultural land use dynamics and to find the underlying processes for non-linearities. Results show that the sources of non-linearities are in the properties of bio-physical processes and in the decision making-process of farmers.  相似文献   

3.
The increasing energy demand, increasing energy dependency, energy supply security, and environmental concerns have become a part of business policies since COP21 agreements in Paris, 2015. Combined cooling, heating, and power (CCHP or tri-generation) systems play an important role in paying the necessary attention to these policies. Tri-generation investment is a complex decision with hybrid use of energy resources. This article aims to reduce the complexity of this decision by the use of Bayesian belief networks in pre-investment stage of tri-generation investment project cycle. The proposed model gives an insight into decision analysis and helps the decision-makers either generate or purchase from it in order to meet the energy demand with different scenarios. The model is studied for a university case. The investment decision for a CCHP (tri-generation) system will be discussed as an alternative for purchasing the electricity and natural gas from the national grids.  相似文献   

4.
ABSTRACT. The limited success of command-and-control policies for reducing nonpoint source (NPS) water pollution mandated under the Federal Water Pollution Control Act (FWPCA) has prompted increased interest in economic incentive policies as an alternative control mechanism. A variety of measures have been proposed ranging from fairly minor modifications of existing policies to substantial revisions including watershed-wide polices that rely on economic incentives. While greater use of economic incentive policies, such as environmental bonds and point/nonpoint source trading is being advocated in the reauthorization of the CWA, the expected effects of individual proposals will be modest. The characteristics of NPS pollution, namely uncertainty and asymmetrical information, underscores that there is no single, ideal policy instrument for controlling the many types of agricultural NPS water pollution. Some of the usual incentive-based policies, such as effluent taxes, are not well suited to the task. Individual incentive policies proposed for the reauthorized CWA, such as pollution trading or deposit/refund systems, are not broadly applicable for heterogeneous pollution situations. Economic incentive policies may be appropriate in some cases, and command-and-control policies will be preferable in others and may in fact complement incentive policies.  相似文献   

5.
Due to environmental constraints and reactive water management practices, water shortages exist across the Everglades ecosystem. A growing human population and continued wetlands damage and loss decrease the system's ability to provide water for sustained natural areas and for human uses. 'The Restudy' is an $8 billion plan to restore the Everglades while also continuing to provide water storage for urban and agricultural areas. The Restudy proposes a mix of water storage systems to provide for the predicted future growth in water demand. This mix is purported to be the most cost-efficient at providing water supplies, within the constraints of unchanged agricultural and urban land use. However, a sensitivity analysis of the Restudy's cost equation reveals that the total cost of water storage systems is influenced by real estate, land acquisition and water treatment costs. The interaction of land use and agricultural policies can affect these cost factors, and can change the relative cost-efficiency between storage systems. Real estate and land acquisition costs are affected by several 1996 Farm Bill provisions, which influence the cost of aboveground water storage systems versus Aquifer Storage and Recovery systems. The Governor's Commission for a Sustainable South Florida recommendations also influence the water storage options available to the Restudy. Due to the Restudy's initial assumptions and constraints, it may not advocate the most economically and ecologically sound remediation.  相似文献   

6.
An Environmental Management System (EMS) has been widely in use by many companies to manage the environmental effects of their operations. The process has recently gained ground in being adopted at city and municipal levels as well as in institutions such as universities. However, an EMS that is conducted at corporate level has some deficiencies when it is applied at city level. These deficiencies are in evaluating environmental goals and policies carried out to mainly ensure that the policies meet ISO 14001 standard and corporate requirements and neglect of public participation. Urban areas differ from companies due to their size, complexity and environmental challenges, high rate of growth and the dynamic nature of urban systems. Therefore, they need an urban environmental management approach that will assess the formulated urban environment policies and goals in a strategic method before implementation, including social dimensions such as public participation. Therefore, this paper proposes a modified approach to incorporate an EMS, called the Sustainable Urban Environmental Management Approach (SUEMA). The approach recognizes the above-mentioned deficiencies and benefits from the advantages of sustainability and Strategic Environmental Assessment (SEA) in the formulation and evaluation of policies, plans and programs. SUEMA is developed to ensure more sustainable urban environmental planning and development.  相似文献   

7.
The aim of this paper is to highlight key social and economic drivers crucial to understanding community acceptance and adoption of decentralised water systems. The review focused on social science literature pertaining to alternative forms of household water, with an emphasis on research examining decentralised water acceptance. Researchers consistently reported that most communities were open to alternative water sources for domestic applications; however, this was highly dependent upon the level of personal contact with the water. Acceptance and adoption of alternative water technology, such as decentralised systems, was influenced by risk perception, water culture, and threat perception. Motivational drivers were also identified as potentially influencing adoption of decentralised systems. A clear limitation of the literature was found to be an over-reliance on measuring people's intentions to adopt alternative water systems and building a conceptual understanding of acceptance solely on hypothetical water supply scenarios. Further, within the social science literature there appears to be a skewing towards focusing on acceptance of centralised alternative water, such as recycled and desalinated water systems. Although there are some research outcomes that are generalizable to the decentralised water context, it is clear that there is a significant gap in the knowledge base of social drivers specific to the acceptance of decentralised water systems and the factors contributing to its widespread use. It is recommended that future research focus on examining public attitudes relevant to decentralised water systems, as well as adoption behaviours among current users of these systems. This will assist in developing policies specific to domestic decentralised water use.  相似文献   

8.
Changes in material use, energy use and emissions profiles of industry are the result of complex interrelationships among a multitude of technological and economic drivers. To better understand and guide such changes requires that attention is paid to the time-varying consequences that technology and economic influences have on an industry's choice of inputs and its associated (desired and undesired) outputs. This paper lays out an approach to improving our understanding of the dynamics of large industrial systems. The approach combines engineering and econometric analysis with a detailed representation of an industry's capital stock structure. A transparent dynamic computer modeling approach is chosen to integrate information from these analyses in ways that foster participation of stakeholders from industry and government agencies in all stages of the modeling process-from problem definition and determination of system boundaries to generation of scenarios and interpretation of results. Three case studies of industrial energy use in the USA are presented-one each for the iron and steel, pulp and paper, and ethylene industry. Dynamic models of these industries are described and then used to investigate alternative carbon emissions and investment-led policies. A comparison of results clearly points towards two key issues: the need for industry specific policy approaches in order to effectively influence industrial energy use, fuel mix and carbon emissions, and the need for longer time horizons than have typically been chosen for the analysis of industrial responses to climate change policies.  相似文献   

9.
Trade-offs between ecosystem conservation and agricultural production can more easily be addressed by shifting the view from the plot scale to the scale of the landscape and integrating biodiversity friendly land use systems into development strategies. The provision of ecosystem services such as watershed protection and carbon sequestration by natural and complex agro-ecosystems can play an important role in making such integrated landscape approaches viable. This special issue brings together papers that were presented at a symposium on agroforestry and landscape scale conservation at the Second World Agroforestry Congress in Nairobi in August 2009. It is divided into two sections focusing on: (1) the biological mechanisms and implications of landscape scale conservation strategies as influenced by land use, especially agroforestry; and (2) the economic drivers and public policies that determine to a large extent the success of agroforestry-based landscape conservation strategies. The contributions provide evidence both for the potential and limitations of agroforestry in landscape scale conservation and development strategies and highlight the importance of economic incentives and policies to promote integrated landscape solutions. This introductory paper summarizes and discusses the contributions and concludes with policy recommendations and research needs.  相似文献   

10.
India has good reasons to be concerned about climate change as it could adversely affect the achievement of vital national development goals related to socio‐economic development, human welfare, health, energy availability and use, and infrastructure. The paper attempts to develop a framework for integrated impact assessment and adaptation responses, using a recently built railroad coastal infrastructure asset in India as an example. The framework links climate change variables — temperature, rainfall, sea level rise, extreme events, and other secondary variables — and sustainable development variables — technology, institutions, economic, and other policies. The study indicates that sustainable development variables generally reduce the adverse impacts on the system due to climate change alone, except when they are inadequately applied. The paper concludes that development is a vital variable for integrated impact assessment. Well crafted developmental policies could result in a less‐GHG intensive future, enhanced adaptive capacities of communities and systems, and lower impacts due to climate change.  相似文献   

11.
During the 1976–77 drought, three principal mechanisms were used to reduce water use in Utah communities: price increases, maximum monthly use restrictions, and restrictions on outdoor watering times. A regression model was developed to explain observed changes in water use, with price, type of restriction, household size, and summer rainfall as independent variables. For an average system, a 1 percent increase in price would reduce water use by 0.07 to 0.09 percent. A 1 percent increase in outdoor watering time restriction reduces use by 0.064 to 0.075 percent. A 1 percent increase in quantity restrictions leads to a reduction in water use of 0.014 to 0.054 percent. The effectiveness of rationing policies is influenced by system characteristics. For example, outdoor watering time restrictions were less effective in systems with above average household size and below average monthly use.  相似文献   

12.
Abstract: Spatio‐temporal linkages between hydrologic and ecologic dimensions of watersheds play a critical role in conservation policies. Habitat potential is influenced by variation along longitudinal and lateral gradients and land use disturbance. An assessment of these influences provides critical information for protecting watershed ecosystems and in making spatially explicit, conservation decisions. We use an ecohydrologic approach that focuses on interface between hydrological and ecological processes. This study focuses on changes in watershed habitat potentials along lateral (riparian), and longitudinal (stream order) dimensions and disturbance (land use). The habitat potentials were evaluated for amphibians, reptiles, mammals, and birds in the Westfield River Watershed of Massachusetts using geographic information systems and multivariate analysis. We use a polynomial model to study nonlinear effects using robust regression. Various spatial policies were modeled and evaluated for influence on species diversity. All habitat potentials showed a strong influence along spatial dimensions and disturbance. The habitat potential for all vertebrate groups studied decreased as the distance from the riparian zone increased. Headwaters and lower order subwatersheds had higher levels of species diversity compared to higher order subwatersheds. It was observed that locations with the least disturbance also had higher habitat potential. The study identifies three policy criteria that could be used to identify critical areas within a watershed to conserve habitat suitable for various species through management and restoration activities. A spatially variable policy that is based on stream order, riparian distance, and land use can be used to maximize watershed ecological benefits. Wider riparian zones with variable widths, protection of headwaters and lower order subwatersheds, and minimizing disturbance in riparian and headwater areas can be used in watershed policy. These management objectives could be achieved using targeted economic incentives, best management practices, zoning laws, and educational programs using a watershed perspective.  相似文献   

13.
Many counties in England have systems of non‐statutory sites of importance for nature conservation in addition to the statutory National Nature Reserves, Sites of Special Scientific Interest and Local Nature Reserves. The paper describes the evolution of such a system over the past 20 years in the metropolitan county of the West Midlands. The system has been recognized by the local planning authorities who have included appropriate policies for the conservation of these sites in statutory development plans. The authority of such a system derives from the use of published criteria for the selection of sites, consensus over the application of these criteria, and consultation with the owners and occupiers of the sites.  相似文献   

14.
Because ecosystem approaches to management adhere to ecological systems rather than human-defined boundaries, collaboration across jurisdiction, agencies, and land ownership is often necessary to achieve effective management of transboundary resources. Local natural resource and land use planners increasingly recognize that while ecosystem management requires looking beyond specific jurisdictions and focusing on broad spatial scales, the approach will partly be implemented at the local level with the coordination of local policies across larger landscapes. This article evaluates the collective capabilities of local jurisdictions to manage large transboundary ecological systems in Florida. Specifically, it combines plan evaluation with geographic information systems (GIS) techniques to map, measure, and analyze the existing mosaic of management across selected ecosystems in the southern portion of the State. Visual and statistical results indicate significant gaps in the management framework of southern Florida that, if filled, could achieve a greater level of consistency and more complete coverage of ecosystem management policies. Based on the spatial distribution of 58 ecosystem management indicators, notable gaps persist in the southwest coast, southeast coast, and central Everglades ecosystems, particularly for wildlife corridors and collaboration with neighboring jurisdictions. We also test for spatial autocorrelation of ecosystem planning scores and find that local jurisdictions with strong ecosystem management capabilities tend to cluster within specific ecosystems. Based on the findings, we make recommendations on how and where local plans can be strengthened to more effectively attain the objectives of ecosystem approaches to management.  相似文献   

15.
Insight into future land use and effective ways to control land-use change is crucial to addressing environmental change. A variety of growth-control policies have been adopted by municipal and regional governments within the United States to try to minimize the ecological impact of continued urbanization, but it is often unclear if those policies can meet the stated ecological goals. Land-use-change models provide a way to generate predictions of future change, while exploring the impact of different land-use policies before irreversible transformations occur. In this article, an approach to modeling land-use policies that focuses on their ecological consequences is described. The policy simulation approach was used to predict future land use in the Barnegat Bay and Mullica River watersheds, in southeastern New Jersey, USA. Four commonly used policies were considered: down-zoning, cluster development, wetlands/water buffers, and open space protection. The results of the analysis suggest that none of the policies modeled were able to alter future land-use patterns, raising questions about the effectiveness of commonly adopted land-use policies. However, the policy modeling approach used in this study proved to be a useful way to determine if adoption of a given policy could improve the likelihood of meeting ecological goals.  相似文献   

16.
ABSTRACT: A mathematical model of agricultural water use and a hydrological and economic simulation model were linked to quantify the economic and hydrological impact of deficit irrigation, increased water application efficiency, and farm storage dams when maintaining an IFR (instream flow requirement) under stochastic water supply conditions. The main finding was that a water conservation policy aimed at reducing the amount of water withdrawn from the river could bring more pressure to bear on stream flow. Water can only be saved if consumptive use is reduced. Increased water application efficiency is detrimental to other users as a result of reduced return flow. The economic cost of maintaining a specific IFR increases with the use of all three strategies as the probability of maintaining the IFR increases. Because of the control that can be exercised over the supply of water, a farm storage dam is the best strategy for minimizing the costs for irrigators. The interaction between water legislation, water policy administration, technology, hydrology, and human value systems necessitates an integrated approach to facilitate water management at catchment level and to formulate policies that will be in the interest of society.  相似文献   

17.
本文系统回顾了新中国成立70年以来生态环境财税政策的历史变迁,以时间为主线,分析其在不同阶段的措施手段,对于制定完善生态环境财税政策,全面推进美丽中国建设具有重大意义。生态环境财税政策大致经历了萌芽发展、探索发展、开拓发展和快速发展四个阶段,从无到有,逐步演化,已形成种类齐全,内容丰富的政策体系,但同时也存在着支出力度和支出效率不足、事权与支出责任相适应的制度不明确、税收政策体系尚不完善等问题。本文提出了增加财政"211节能环保"科目支出规模、健全事权与支出责任相匹配的财政制度、完善环境保护税和税收优惠政策、建立基于绩效的资金分配机制等优化新时期生态环境财税政策的建议。  相似文献   

18.
Land-Cover Change Trajectories in Northern Ghana   总被引:3,自引:0,他引:3  
Land-cover change trajectories are an emergent property of complex human–environment systems such as the land-use system. An understanding of the factors responsible for land change trajectories is fundamental for land-use planning and the development of land-related policies. The aims of this study were to characterize and identify the spatial determinants of agricultural land-cover change trajectories in northern Ghana. Land-cover change trajectories were defined using land-cover maps prepared from Landsat Thematic Mapper dataset acquired in 1984, 1992, and 1999. Binary logistic regression was used to model the probability of observing the trajectories as a function of spatially explicit biophysical and socioeconomic independent variables. Population densities generally increased along the continuum of land-use intensity, whereas distance from market and roads generally decreased along this continuum. Apparently, roads and market serve as incentives for settlement and agricultural land use. An increase in population density is an important spatial determinant only for trajectories where the dominant change process is agricultural extensification. A major response to population growth is an increase in cultivation frequency around the main market. Agricultural intensification is highly sensitive to accessibility by roads. The increase in land-use intensity is also associated with low soil quality. These results suggest the need for policies to restore soil fertility for agricultural sustainability. The models also provide a means for identifying functional relationships for in-depth analyses of land-use change in Ghana.  相似文献   

19.
Problems of deteriorating water quality and the prospects of large invest ments for treatment facilities have motivated government decision makers to seek more cost-effective means to manage water quality. The most preferred policy advocated by economists is based on economic incentives. But the response of water quality managers to a particular incentive system cannot be predicted a priori . Before any incentive system is implemented, its effectiveness must be evaluated. Mathematical programming models have been used for this purpose. Experimental economics provides an alternative mechanism for testing the effectiveness of such a system. It can also help identify the necessary parameters of incentive-based systems. The objective of this paper is to describe the results of an experiment for evaluating the effectiveness of managing water quality under two different policies: a command and control policy; and a transferable discharge permit (TDP) policy. A review of previous research on the effectiveness of TDP systems is provided along with arguments supporting the use of experimental economics to investigate these problems. The particular experiments developed for this research along with the experimental procedures are described. Key results and observations from the experiments are presented.  相似文献   

20.
The effectiveness of a decision-support tool created to identify protected-area potential within the Nova Forest Alliance (NFA) of Nova Scotia, Canada is assessed from the perspective of a public participatory geographic information system (PPGIS) approach. The application sought to create an integrated GIS-based decision-support tool for community-focused communication and conservation assessment among NFA partners (including private woodland owners, government agencies, forest companies, and non-government organizations) and potential application within other model forests in Canada. The application illustrated that the GIS-based tool, once set up and populated with the necessary data, was able to generate effective visual alternatives to support decision making within the NFA community and elsewhere. However, from a PPGIS perspective, the application faced challenges that influenced the efficacy of its implementation: (1) limitations arose around data quality, use and sharing policies; (2) although opportunities for participation by the NFA partnership were initiated, these proved insufficient to achieve adequate engagement, buy in and support for the process and outcomes; and (3) the expert-grounded GIS-based tool requires a greater degree of expertise than may currently be present in the community. These challenges limit its ongoing use in the NFA and its potential utility in other model forests. For PPGIS-decision-support applications to be effective in the NFA and elsewhere, it is suggested that the following conditions be met: (1) implementation of geographically based data policies to allow for greater data accessibility, specifically with fewer bureaucratic and private sector barriers; (2) engagement of community partners in the initial project design, goal-setting and subsequent stages, even if this requires extensions to anticipated timelines; and (3) development of effective participatory technical systems that meet the needs of participants without being so complex as to constitute a barrier to their use.  相似文献   

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