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1.
This study explores different socio-economic and institutional factors influencing the adoption of improved soil conservation technology (ISCT) on Bari land (Rainfed outward sloping terraces) in the Middle Mountain region of Central Nepal. Structured questionnaire survey and focus group discussion methods were applied to collect the necessary information from farm households. The logistic regression model predicted seven factors influencing the adoption of improved soil conservation technology in the study area including years of schooling of the household head, caste of the respondent, land holding size of the Bari land, cash crop vegetable farming, family member occupation in off farm sector, membership of the Conservation and Development Groups, and use of credit. The study showed that technology dissemination through multi-sectoral type community based local groups is a good option to enhance the adoption of improved soil conservation technology in the Middle Mountain farming systems in Nepal. Planners and policy makers should formulate appropriate policies and programs considering the farmers' interest, capacity, and limitation in promoting improved soil conservation technology for greater acceptance and adoption by the farmers.  相似文献   

2.
The Ozegahara peatland, in the Nikko-Oze National Park in Japan, is ecologically significant because of its oligotrophic environment; it is one of the most strictly preserved areas in the country. The isotope ratio of nitrogen (15N/14N) and carbon (13C/12C) and C/N ratio of peat moss (Sphagnum spp.) and sundew (Drosera rotundifolia) in the peatland were analyzed. The correlation of the isotope ratio with some parameters (sundew population density, number of trapped insects, water level, bog myrtle coverage, and visitor density) was investigated. The nitrogen isotope ratio of sundew showed the most significant covariation with visitor density, where sundew from lunch areas or along busy walkways showed a higher nitrogen isotope ratio. The nitrogen isotope ratio of peat moss covaried, not only with route traffic frequency but also with water level, bog myrtle coverage, and number of trapped insects by sundew, indicating that factors other than the visitor level influence the local nitrogen cycle. This study suggests that the nitrogen imported into the peatland by visitors is a principal factor to be monitored for the maintenance of the natural environment.  相似文献   

3.
The ability of both regulators and farmers themselves to monitor the impact of environmental practices may be an issue with nonpoint source pollution. Effects that can be perceived via direct sensory evidence provide information at low cost. Results from a survey of livestock farmers suggest that a practice that has more obvious effects on water quality, manure application setbacks, is more likely to be adopted than a more complicated one with less visible effects, manure testing. Farmers’ perceptions of the profitability of the two practices were similar. The importance of observability and complexity has implications for educational programs.  相似文献   

4.
The state of solid waste recycling by scavengers in Onitsha, a heavily commercial city in Anambra State, and some other urban areas such as Nsukka, Enugu, and Port Harcourt was analyzed. Data were obtained through interviews of scavengers who deal with recyclables. Although the activities of scavengers are sub-optimal, they can have a great impact on Nigerian economy with respect to resource conservation, creation of job opportunities, and reduction of the magnitude of waste disposal problems. A cost analysis is presented to compare the different forms of recycling utilized by municipal solid waste management. It is shown that a well-planned recycling program with recycling and composting would result in 18.6% savings in waste management costs and 57.7% in landfill avoidance costs. However, if the compost materials are not recycled, the corresponding savings in cost become 8.6% and 28.6%, respectively. The option with the lowest cost involves encouraging individual households to separate at the source their recyclables, which are bought by scavengers. This results in 78.0% savings in waste management cost and 79.5% landfill avoidance cost. A low-cost approach aimed at the integration of scavenging activities into conventional solid waste management is presented.  相似文献   

5.
Advancement of modern agricultural biotechnology has brought various potential benefits to humankind, but at the same time ethical concerns regarding some applications such as genetically modified foods (GMF) have been raised among the public. Several questions are being posed; should they utilize such applications to improve quality of their life, or should they refrain in order to save themselves from any associated risk? What are the ethical principles that can be applied to assess these applications? By using GMF as a case study, this paper discusses possible answers to these questions from Islamic perspective. Such answers are based on the understanding of the Islamic concept of maslahah (benefit) and mafsadah (harm) as well as the Islamic principles of priority. There is no specific GMF that has been declared as unlawful by Muslim scholars thus far. Nevertheless, they generally state that any GMF that contains unlawful substance is prohibited in Islam. Such statement can be understood since Islam puts highest priority to preserve shari’ah (Islamic law) which prescribes the lawful and unlawful things in human life. Priorities have also been given to preserve human health and environment therefore any GMF that may inflict harm on both entities is also considered as unlawful.  相似文献   

6.
Abstract

The popularity of sustainability indicators is almost inescapable. From the early pioneers such as the ‘Sustainable Seattle’ project (Atkisson, ‘Developing Indicators of a Sustainable Community: lessons from Sustainable Seattle’, in: D. Satterthwaite (Ed), The Earthscan Reader in Sustainable Cities, London, Earthscan, 1996) to the comprehensive European Union benchmarking launched in 2003 (European Commission, European Common Indicators: towards a local sustainability profile, Milan, Ambiente Italia, 2003), it seems that consensus has been reached about the positive impacts that establishing sustainability indicators can bring. This paper uses the case of developing sustainability indicators on the Island of Guernsey over the last three years to show that Agenda 21's call to activate grassroots action is being realised, but in ways that are neither top-down and modernist in approach nor bottom-up and postmodernist as Agenda 21 advocates. Although best practice literature often suggests that community involvement must be engaged prior to designing sustainability indicators, this paper explores the reasons why this is not always possible. Guernsey's case is used to show how it only became possible to generate interest in the indicator process once they were actually up and running. However, it also shows that once interest was secured by a few relevant stakeholders it became possible to further evolve the indicators in a process that has slowly been attracting more and more of the Island's community.  相似文献   

7.
8.
The performance characteristics of a solar air heater can effectively be improved by providing artificial roughness in the form of protrusions and dimples of various shapes, sizes, and orientations on the underside of heated surface. An extensive literature review on artificial roughness elements has been carried and the correlations developed for heat transfer and friction factor for roughened solar air collector have been discussed and presented in this paper. The performance parameter has also been computed and compared with various kinds and shapes of roughness geometries using correlations developed by various investigators. The optimum values of the roughness parameters obtained by several investigators have also been discussed.  相似文献   

9.
Zoning and applying Limits of Acceptable Change (LAC) are two promising strategies for managing tourism in Marine Protected Areas (MPAs). Typically, these management strategies require the collection and integration of ecological and socioeconomic data. This problem is illustrated by a case study of Koh Chang National Marine Park, Thailand. Biophysical surveys assessed coral communities in the MPA to derive indices of reef diversity and vulnerability. Social surveys assessed visitor perceptions and satisfaction with conditions encountered on snorkelling tours. Notably, increased coral mortality caused a significant decrease in visitor satisfaction. The two studies were integrated to prescribe zoning and “Limits of Acceptable Change” (LAC). As a biophysical indicator, the data suggest a LAC value of 0.35 for the coral mortality index. As a social indicator, the data suggest that a significant fraction of visitors would find a LAC value of under 30 snorkellers per site as acceptable. The draft zoning plan prescribed four different types of zones: (I) a Conservation Zone with no access apart from monitoring or research; (II) Tourism Zones with high tourism intensities at less vulnerable reefs; (III) Ecotourism zones with a social LAC standard of <30 snorkellers per site, and (IV) General Use Zones to meet local artisanal fishery needs. This study illustrates how ecological and socioeconomic field studies in MPAs can be integrated to craft zoning plans addressing multiple objectives.  相似文献   

10.
Curbside recycling efforts have made an important contribution to waste containment, but many communities have specific limitations on what products can be recycled within their community bins (e.g., no cartons, styrofoam, soft plastics) and must rely on depots for recycling these other items. These specialty depots typically take the form of local community or large central municipal sites. The purpose of this randomized trial was to examine messages targeting (1) awareness/instructions, (2) utility, (3) affect, and (4) planning upon community and central depot recycling across eight weeks. One hundred and seventy-six community-dwelling residents between the ages of 18–65 years who self-identified as having the potential to improve their depot recycling activities completed baseline recycling measures and then were randomly assigned to one of the four messaging conditions. One hundred and forty-four of these participants subsequently answered follow-up recycling behavior measures four and eight weeks later. Intention to treat analyses showed that depot recycling increased significantly from baseline to four weeks. The effect waned for community recycling while holding for municipal depot recycling at eight weeks. Distance to recycling depot (closer proximity resulted in greater community recycling), access to a car (low access resulted in greater community recycling), and baseline recycling behavior (no prior recycling resulted in greater behavior change) all acted as significant moderators of the effect. There was no time by group interaction among conditions. The findings support the use of basic instructions – as a minimum – for promoting depot recycling efforts and provide evidence that local community depots, in conjunction with municipal depots, are important to increasing recycling behavior.  相似文献   

11.
The water resources of most small island developing states (SIDS) are often very limited and require special consideration to ensure that they are developed and managed in a sustainable manner. Many small islands, typically located in the humid tropics, have no surface water resources and rely on limited groundwater resources in the form of thin freshwater lenses. The exposed location of small islands makes them particularly vulnerable to natural disasters such as cyclones, floods and droughts. Pollution from population centres and from agricultural and other activities is an increasing problem. This article provides an overview of the water resources of small islands, and the main problems and issues related to water resources. Some suggested solutions, based on practical experiences, are offered for water resource assessment and monitoring programmes, and water resource development. Water resource policy, planning and management issues are also addressed, and suggested approaches for resolving some of the major water resource problems presented.  相似文献   

12.
ABSTRACT: Florida water resources are among the most abundant in the United States, with Florida receiving the second‐highest mean annual rainfall of all states. However, water supply issues have troubled the state due to the highly variable spatial and temporal distributions of water supply and demand, and they are aggravated by the population's preference for settling in coastal regions where freshwater resources are scarce. Historically, the competing issues of water resource development and natural systems protection have placed water management agencies and local governments at odds. In 1997, the Florida Legislature enacted several major changes to Florida water law in an attempt to improve water resource planning and protection. This paper briefly reviews the history of water management in Florida with an emphasis on decisions culminating in the 1997 legislation, which requires the development of minimum flows and levels. Also examined is the impact of the 1997 law on water management. Efforts made to comply with legislative mandates are summarized; these include, to date, establishment of minimum flows and levels on 209 water bodies and budgeting in excess of $1.4 billion for water resource development projects.  相似文献   

13.
This paper seeks to identify some promising policy options which could be part of a strategic and holistic effort to address India's future water challenges. Significant increases in agricultural water productivity would be a major factor in reducing the need for developing new water sources. Crop diversification, appropriately targeted to account for the present agricultural systems and available water resources, will increase productivity. Furthermore, much more emphasis needs to be placed on effective management of the groundwater resources through renewed efforts to enhance artificial recharge and conservation. Also, efforts should be revived to improve the existing surface irrigation systems. In particular, systems could be reconfigured to provide a more reliable water supply and allow effective community level management, where appropriate. Finally, while some of the increasing demands from domestic and industrial users will be met by the development of groundwater and reallocation of water from the agricultural sector, this will not be sufficient. Given that such conditions are emerging in states with high economic growth and relatively water scarce basins, this will require the further development of water resources. In some cases, these conditions along with the demand for reliable water for high value crops, will be part of the justification for inter‐basin transfers.  相似文献   

14.
Sharing waters: Post-Rio international water management   总被引:4,自引:0,他引:4  
Transcending human-defined political and administrative boundaries, the world's transboundary freshwater resources pose particularly challenging management problems. Water resource users at all scales frequently find themselves in direct competition for this economic and life-sustaining resource, in turn creating tensions, and indeed conflict, over water supply, allocation, and quality. At the international scale, where the potential for conflict is of particular concern, significant efforts are underway to promote greater cooperation in the world's international river basins, with notable achievements in the past decade following the Dublin and Rio conferences. Over the past ten years, the international community has adopted conventions, declarations, and legal statements concerning the management of international waters, while basin communities have established numerous new basin institutions. Despite these developments, significant vulnerabilities remain. Many international basins still lack any type of joint management structure, and certain fundamental management components are noticeably absent from those that do. An understanding of these weaknesses, however, offers an opportunity for both the international and basin communities to better respond to the specific institution-building needs of basin communities and thereby foster broader cooperation over the world's international water resources.  相似文献   

15.
Fresh water has become a very topical, emotive and sensitive issue in Zimbabwe following the recent continued droughts in conjunction with lack of finance to expand water resources development. Heated debates have arisen over the availability, allocation, distribution, disbursement and conservation of this precious resource. A great deal of inefficiency has also resulted from Government Ministries or Departments playing all the roles, from policymaking to supply operations. Government authorities often make the mistake of controlling day-to-day management of water and sewage services. In fact, greater accountability results when Government authorities focus on policymaking, establishing regulatory regimes that provide incentives for achieving goals and sanctions for serious failures, while giving sufficient autonomy to entities responsible for investment and operations to control outcomes. It is becoming more and more evident throughout the world that provision of water, as opposed to the planning and allocation of the water resource, should be handled by commercial undertakers. Indeed, Zimbabwe and its neighbours are currently involved with changing the status of their water departments to corporate entities; Botswana, Malawi, Namibia, South Africa and Zambia have already commercialised or are currently in the process of commercialising their freshwater supply services.  相似文献   

16.
Beijing's local water resources have been overexploited and the ecological and environmental pressures exceed the carrying capacity of this densely populated megacity. This article examines the current status of Beijing's water resources with respect to its industrial, residential, and eco‐environmental water usage and the challenges it may face in the near future. The article describes the context of water uses, the steps taken by Beijing to alleviate the water shortage problems, and challenges to Beijing's abilities to meet its urgent and future water needs. A multipronged strategy is proposed that aims at both the present problems and the anticipated future challenges. In particular, engineering and institutional approaches for Beijing's successful transition from overexploitation to sustainable utilization of water resources are explained. Actions include reasonable water utilization, water conservation, reclaimed wastewater, and importing water from neighboring areas. We conclude that Beijing must take additional steps in water resource management to ensure its sustainable development that involves continued urbanization sprawls and population growth. Future water resource management strategies should focus on strengthening water demand management through water conservation, efficient interbasin water transfers, use of nontraditional water resources, strategically reserving water supply, and promoting rehabilitation of the eco‐environments.  相似文献   

17.
REALM (REsource ALlocation Model) is a generalised computer simulation package that models harvesting and bulk distribution of water resources within a water supply system. It is a modeling tool, which can be applied to develop specific water allocation models. Like other water resource simulation software tools, REALM uses mass-balance accounting at nodes, while the movement of water within carriers is subject to capacity constraints. It uses a fast network linear programming algorithm to optimise the water allocation within the network during each simulation time step, in accordance with user-defined operating rules. This paper describes the main features of REALM and provides potential users with an appreciation of its capabilities. In particular, it describes two case studies covering major urban and rural water supply systems. These case studies illustrate REALM's capabilities in the use of stochastically generated data in water supply planning and management, modelling of environmental flows, and assessing security of supply issues.  相似文献   

18.
Shrinking freshwater supplies pose particular threats in international drainage basins, which serve some 40% of the global population and account for around 60% of the world's river flows. The use and management of these basins are increasingly governed by treaties between the riparian states. While the rules of international law, properly understood, are sufficiently flexible to permit adaptation to changing conditions such as development, population growth and climate change, treaties are essentially rigid instruments that are modifiable only under certain limited conditions. Countries should take this fact into account in designing the regimes to govern their shared freshwater resources, including joint management institutions.  相似文献   

19.
A multi-objective optimisation approach to water management   总被引:3,自引:0,他引:3  
The management of river basins is complex especially when decisions about environmental flows are considered in addition to those concerning urban and agricultural water demand. The solution to these complex decision problems requires the use of mathematical techniques that are formulated to take into account conflicting objectives. Many optimization models exist for water management systems but there is a knowledge gap in linking bio-economic objectives with the optimum use of all water resources under conflicting demands. The efficient operation and management of a network of nodes comprising storages, canals, river reaches and irrigation districts under environmental flow constraints is challenging. Minimization of risks associated with agricultural production requires accounting for uncertainty involved with climate, environmental policy and markets. Markets and economic criteria determine what crops farmers would like to grow with subsequent effect on water resources and the environment. Due to conflicts between multiple goal requirements and the competing water demands of different sectors, a multi-criteria decision-making (MCDM) framework was developed to analyze production targets under physical, biological, economic and environmental constraints. This approach is described by analyzing the conflicts that may arise between profitability, variable costs of production and pumping of groundwater for a hypothetical irrigation area.  相似文献   

20.
Fuzzy pricing for urban water resources: model construction and application   总被引:2,自引:0,他引:2  
A rational water price system plays a crucial role in the optimal allocation of water resources. In this paper, a fuzzy pricing model for urban water resources is presented, which consists of a multi-criteria fuzzy evaluation model and a water resources price (WRP) computation model. Various factors affecting WRP are comprehensively evaluated with multiple levels and objectives in the multi-criteria fuzzy evaluation model, while the price vectors of water resources are constructed in the WRP computation model according to the definition of the bearing water price index, and then WRP is calculated. With the incorporation of an operator's knowledge, it considers iterative weights and subjective preference of operators for weight-assessment. The weights determined are more rational and the evaluation results are more realistic. Particularly, dual water supply is considered in the study. Different prices being fixed for water resources with different qualities conforms to the law of water resources value (WRV) itself. A high-quality groundwater price computation model is also proposed to provide optimal water allocation and to meet higher living standards. The developed model is applied in Jinan for evaluating its validity. The method presented in this paper offers some new directions in the research of WRP.  相似文献   

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