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1.
Land-cover types were analyzed for 1970, 1990 and 2000 as the bases for determining land-use systems and their influence on the resilience of tropical rain forests in the Tehuantepec Isthmus, Mexico. Deforestation (DR) and mean annual transformation rates were calculated from land-cover change data; thus, the classification of land-use change processes was determined according to their impact on resilience: a) Modification, including land-cover conservation and intensification, and b) Conversion, including disturbance and regeneration processes. Regeneration processes, from secondary vegetation under extensive use, cultivated vegetation under intensive use, and cultivated or induced vegetation under extensive use to mature or secondary vegetation, have high resilience capacity. In contrast, cattle-raising is characterized by rapid expansion, long-lasting change, and intense damages; thus, recent disturbance processes, which include the conversion to cattle-raising, provoke the downfall of the traditional agricultural system, and nullify the capacity of resilience of tropical rain forest. The land-use cover change processes reveal a) the existence of four land-use systems (forestry, extensive agriculture, extensive cattle-raising, and intensive uses) and b) a trend towards the replacement of agricultural and forestry systems by extensive cattle-raising, which was consolidated during 1990–2000 (DR of evergreen tropical rain forest=4.6%). Only the forestry system, which is not subject to deforestation, but is affected by factors such as selective timber, extraction, firewood collection, grazing, or human-induced fire, is considered to have high resilience (2 years), compared to agriculture (2–10 years) or cattle-raising (nonresilient). It is concluded that the analysis of land-use systems is essential for understanding the implications of land-use cover dynamics on forest recovery and land degradation in tropical rain forests.  相似文献   

2.
The Khanikhola watershed in Sikkim is agrarian with about 50% area under rain-fed agriculture representing the conditions of the middle mountains all over the Himalaya. The study was conducted to assess overland flow, soil loss and subsequent nutrient losses from different land uses in the watershed, and identify biotechnological inputs for management of mountain farming systems. Overland flow, soil and nutrient losses were very high from open agricultural (cropped) fields compared to other land uses, and more than 72% of nutrient losses were attributable to agriculture land use. Forests and large cardamom agroforestry conserved more soil compared to other land uses. Interventions, like cultivation of broom grass upon terrace risers, N2-fixing Albizia trees for maintenance of soil fertility and plantation of horticulture trees, have reduced the soil loss (by 22%). Soil and water conservation values (> 80%) of both large cardamom and broom grass were higher compared to other crops. Use of N2-fixing Albizia tree in large cardamom agroforestry and croplands contributed to soil fertility, and increased productivity and yield. Bio-composting of farm resources ensured increase in nutrient availability specially phosphorus in cropped areas. Agricultural practices in mountain areas should be strengthened with more agroforestry components, and cash crops like large cardamom and broom grass in agroforestry provide high economic return and are hydroecologically sustainable.  相似文献   

3.
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   

4.
Agroforestry is often an economically viable land-use option for the environmental rehabilitation of salinized cropping areas in irrigated drylands, but afforestation initiative at the farm level is subject to various socio-political constraints. We analyzed the factors that affect farmer decisions with respect to the agroforestry adoption using an ex ante approach through Ethnographic Decision Tree Modeling (EDTM). Constraints on agroforestry adoption were identified via a review of legal documents, focus-group discussions, and a farm survey in northwest Uzbekistan. The findings highlighted the importance of farmer perceptions of risk with respect to decision making surrounding the adoption of alternative land uses. The EDTM analysis allowed determining those policy incentives for afforestation that could directly influence the decision-making process of potential participants. In particular, there is a need for increased land-use flexibility, improved land tenure and tree plantation proprietorship security, increased awareness raising and training in agroforestry practices, and greater institutional support.  相似文献   

5.
Agricultural expansion and deforestation are spatial processes of land transformation that impact on landscape pattern. In peninsular Malaysia, the conversion of forested areas into two major cash crops—rubber and oil palm plantations—has been identified as driving significant environmental change. To date, there has been insufficient literature studying the link between changes in landscape patterns and land-related development policies. Therefore, this paper examines: (i) the links between development policies and changes in land use/land cover and landscape pattern and (ii) the significance and implications of these links for future development policies. The objective is to generate insights on the changing process of land use/land cover and landscape pattern as a functional response to development policies and their consequences for environmental conditions. Over the last century, the development of cash crops has changed the country from one dominated by natural landscapes to one dominated by agricultural landscapes. But the last decade of the century saw urbanization beginning to impact significantly. This process aligned with the establishment of various development policies, from land development for agriculture between the mid 1950s and the 1970s to an emphasis on manufacturing from the 1980s onward. Based on a case study in Selangor, peninsular Malaysia, a model of landscape pattern change is presented. It contains three stages according to the relative importance of rubber (first stage: 1900–1950s), oil palm (second stage: 1960s–1970s), and urban (third stage: 1980s–1990s) development that influenced landscape fragmentation and heterogeneity. The environmental consequences of this change have been depicted through loss of biodiversity, geohazard incidences, and the spread of vector-borne diseases. The spatial ecological information can be useful to development policy formulation, allowing diagnosis of the country’s “health” and sustainability. The final section outlines the usefulness of landscape analysis in the policy-making process to prevent further fragmentation of the landscape and forest loss in Malaysia in the face of rapid economic development.
Adnan A. HezriEmail:
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6.
There are several claims in the literature that social desirability concerns affect people’s response to self-reported measures of environmental attitudes and ecological behaviour. However, only a few empirical studies have indirectly evaluated the impact of social desirability on environmental issues measures, and those who did have found only a low impact. This article describes two studies that explicitly address whether socially desirable responding has direct and moderating effects on self-reported environmental attitudes and ecological behaviour. Results from correlational and moderated multiple regression analyses from both studies showed that social desirability had only a weak direct effect on environmental attitudes (but not ecological behaviour), and had no moderating effect on the environmental attitudes–ecological behaviour relationship. Implications of these findings for research on environmental issues are discussed.
Taciano L. MilfontEmail:
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7.
Food production and consumption cause significant environmental burdens during the product life cycles. As a result of intensive development and the changing social attitudes and behaviors in the last century, the agrofood sector is the highest resource consumer after housing in the EU. This paper is part of an effort to estimate environmental impacts associated with life cycles of the agrofood chain, such as primary energy consumption, water exploitation, and global warming. Life cycle assessment is used to investigate the production of the following citrus-based products in Italy: essential oil, natural juice, and concentrated juice from oranges and lemons. The related process flowcharts, the relevant mass and energy flows, and the key environmental issues are identified for each product. This paper represents one of the first studies on the environmental impacts from cradle to gate for citrus products in order to suggest feasible strategies and actions to improve their environmental performance.
Marina Mistretta (Corresponding author)Email:
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8.
The East Usambara Mountains, recognized as one of the 25 most important biodiversity hot spots in the world, have a high degree of species diversity and endemism that is threatened by increasing human pressure on resources. Traditional slash and burn cultivation in the area is no longer sustainable. However, it is possible to maintain land productivity, decrease land degradation, and improve rural people’s livelihood by ameliorating cultivation methods. Improved agroforestry seems to be a very convincing and suitable method for buffer zones of conservation areas. Farmers could receive a reasonable net income from their farm with little investment in terms of time, capital, and labor. By increasing the diversity and production of already existing cultivations, the pressure on natural forests can be diminished. The present study shows a significant gap between traditional cultivation methods and improved agroforestry systems in socio-economic terms. Improved agroforestry systems provide approximately double income per capita in comparison to traditional methods. More intensified cash crop cultivation in the highlands of the East Usambara also results in double income compared to that in the lowlands. However, people are sensitive to risks of changing farming practices. Encouraging farmers to apply better land management and practice sustainable cultivation of cash crops in combination with multipurpose trees would be relevant in improving their economic situation in the relatively short term. The markets of most cash crops are already available. Improved agroforestry methods could ameliorate the living conditions of the local population and protect the natural reserves from human disturbance.  相似文献   

9.
A cost-effectiveness analysis was performed to evaluate the competitiveness of seminatural Free Water Surface (FWS) wetlands compared to traditional wastewater-treatment plants. Six scenarios of the service costs of three FWS wetlands and three different wastewater-treatment plants based on active sludge processes were compared. The six scenarios were all equally effective in their wastewater-treatment capacity. The service costs were estimated using real accounting data from an experimental wetland and by means of a market survey. Some assumptions had to be made to perform the analysis. A reference wastewater situation was established to solve the problem of the different levels of dilution that characterize the inflow water of the different systems; the land purchase cost was excluded from the analysis, considering the use of public land as shared social services, and an equal life span for both seminatural and traditional wastewater-treatment plants was set. The results suggest that seminatural systems are competitive with traditional biotechnological systems, with an average service cost improvement of 2.1-fold to 8-fold, according to the specific solution and discount rate. The main improvement factor was the lower maintenance cost of the seminatural systems, due to the self-regulating, low artificial energy inputs and the absence of waste to be disposed. In this work, only the waste-treatment capacity of wetlands was considered as a parameter for the economic competitiveness analysis. Other goods/services and environmental benefits provided by FWS wetlands were not considered.
Daniel FrancoEmail:
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10.
Common decision support tools and a growing body of knowledge about ecological recovery can help inform and guide large state and federal restoration programs affecting thousands of impaired waters. Under the federal Clean Water Act (CWA), waters not meeting state Water Quality Standards due to impairment by pollutants are placed on the CWA Section 303(d) list, scheduled for Total Maximum Daily Load (TMDL) development, and ultimately restored. Tens of thousands of 303(d)-listed waters, many with completed TMDLs, represent a restoration workload of many years. State TMDL scheduling and implementation decisions influence the choice of waters and the sequence of restoration. Strategies that compare these waters’ recovery potential could optimize the gain of ecological resources by restoring promising sites earlier. We explored ways for states to use recovery potential in restoration priority setting with landscape analysis methods, geographic data, and impaired waters monitoring data. From the literature and practice we identified measurable, recovery-relevant ecological, stressor, and social context metrics and developed a restorability screening approach adaptable to widely different environments and program goals. In this paper we describe the indicators, the methodology, and three statewide, recovery-based targeting and prioritization projects. We also call for refining the scientific basis for estimating recovery potential.
Paul ZephEmail:
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11.
In this short essay it is argued that recent criticisms portraying the activist environmental movement as overly pessimistic are valid and that the communication of this pessimism to the public at large has been largely counterproductive to the objectives of environmentalists. It is argued that, in contrast to historic assumptions of a ‘progress paradigm’ that epitomized the widely held optimism of the past, the shock tactics and pessimistic media campaigns employed by the activist environmental movement, and the media that capitalizes upon those campaigns, have contributed to the creation of a figurative hopeless age. The key characterization of the hopeless age is the widely held assumption that the future will be worse than the present and that the lives of future generations will be diminished relative to our own. It is argued that the creation of this social-psychological phenomenon is counterproductive to the aims of the environmental movement and that the restoration of a collective vision and message of hope would be far more productive. Lastly, some reasons for a hopeful outlook are suggested.
Andrew McKinleyEmail: Email:
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12.
We examined the prevalence of residential development that occurs with consideration of the natural features of the site, known as conservation design, within county-level planning jurisdictions across Northern Indiana. Using data from telephone interviews with representatives of planning departments, jurisdictions were ranked based on reported use of conservation design. Three categories of use emerged from the data: no use, use of individual practices associated with conservation design, and integration of multiple conservation design practices. Qualitative data analysis revealed that conservation design practices were not being used widely and, when used, were often used to fulfill stormwater requirements. Statistical analysis, using data from interviews, spatial data sets, and the U.S. Census Bureau, identified several significant positive predictors of the levels of conservation design use including conversion of forest or agricultural land cover to urban uses and education levels in the jurisdiction. Many of the interviewees noted that agricultural land is perceived to meet open space needs within their counties. Given that agricultural land does not fully meet all ecosystem needs, education about the benefits of other types of open space is suggested.
Linda Stalker Prokopy (Corresponding author)Email:
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13.
Making Capacity Building Meaningful: A Framework for Strategic Action   总被引:1,自引:0,他引:1  
This paper aims to give practical meaning to ‘capacity building’ through (a) identifying a suite of practical measures, such as mentoring or best practice guidelines, that have been shown to or are considered to build human, social, institutional, and economic capital; (b) placing these measures within a broader systems framework; and (c) exploring stakeholder feedback on specific measures to inform framework implementation. The 29 measures described provide actors, whether government or nongovernment, with a suite of practical investment choices for building capacity. These measures are then clustered into eight groups according to their primary purpose and placed within a systems framework. The framework provides a tool for actors with responsibilities for or an interest in capacity building to inform more holistic and strategic targeting of effort and investment. Stakeholder feedback gathered through surveys and workshops is subsequently reported to further inform implementation of specific measures within the framework’s eight groupings. The framework presented may be built upon through the identification and inclusion of further capacity building measures. The research is conducted within the context of decentralized governance arrangements for natural resource management (NRM), with specific focus on Australia’s recently formalized 56 NRM regions and their community-based governing boards as an informative arena of learning. Application of the framework is explored in the Australian setting through the identification and comparison of measures supported and most preferred by four major stakeholder groups, namely board members, regional NRM organization staff, policy/research interests, and Indigenous interests. The research also examines stakeholder perceptions of capacity issues, and whether these issues are likely to be addressed through implementing their preferred measures.
Lisa RobinsEmail:
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14.
The use of voluntary programs targeting resource conservation on private land has become increasingly prevalent in environmental policy. Voluntary programs potentially offer significant benefits over regulatory and market-based approaches. This article examines the factors affecting landowner participation in voluntary forest conservation programs using a combination of parcel-level GIS and remotely sensed data and semi-structured interviews of landowners in Monroe County, Indiana. A logistic regression model is applied to determine the probability of participation based on landowner education, membership in other non-forest voluntary programs, dominant land use activity, parcel size, distance from urban center, land resource portfolios, and forest cover. Both land use activity and the spatial configuration of a landholder’s resource portfolio are found to be statistically significant with important implications for the design and implementation of voluntary programs.
Derek KauneckisEmail:
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15.
Sustainability assessment (SA) is a holistic and long-range strategic instrument capable of assisting policy-making in electing, and deciding upon, future development priorities. The outcomes of an SA process become more relevant and strengthened when conducted with multi-stakeholder engagement, which provides for multiple dialogues and perspectives. This was the object of research of the SA team in the context of BioScene (Scenarios for Reconciling Biodiversity Conservation with Declining Agriculture Use in Mountain Areas in Europe), a three-year project (2002–2005) funded by the European Union 5th Framework Program, which aimed to investigate the implications of agricultural restructuring and decline for biodiversity conservation in the mountain areas of Europe, using three distinct methodological streams: the ecological, the socio-economic, and the SA approaches. The SA approach drew on the previous two to assess the importance for biodiversity management of different scenarios of agri-environmental change and rural policy in six countries (France, Greece, Norway, Slovakia, Switzerland, and the United Kingdom), develop causal chains, include stakeholder views, and identify potential contributions for, or conflicts with, sustainability. This article tells how SA was used, what sustainability meant in each study area through different objectives of sustainability considered, discusses the methods used in SA, and the benefits arising. The SA was conducted by a team independent of any study area, who developed and oversaw the application of the SA methodology, assisting national teams, and developing a cross-country understanding of the sustainability of proposed scenarios in the different geographical and social contexts, and their implications for policy-making. Finally, it reflects on the persistent challenges of interdisciplinary research, compounded by multi-cultural teams, and concludes on the BioScene’s lessons for the further development and application of SA.
William R. SheateEmail:
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16.
In the United States, the common interest often is conceived as a by-product of the pluralist, interest-group-driven democratic process. Special interests dominate in many political arenas. Consequently, we have lost the language, vocabulary, and ability to talk about the common interest. The way to reverse this trend is to develop and practice with new tools that allow us to articulate what we mean by the common interest in specific contexts. In this article, we leveraged the literature on procedural, substantive, and pragmatic decision making to illustrate how they work together to demonstrate whether and how the common interest was served in three case studies of Healthy Forests Restoration Act implementation on the Apache-Sitgreaves National Forest in Arizona. In two of the cases we found that the common interest was mostly served, while in the third case it was not. Our results raise questions about the ability of procedural criteria or substantive criteria alone to determine effectiveness in decision making. When evaluated together they provide a more complete understanding of how the common interest is or is not served.
Toddi A. SteelmanEmail:
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17.
Tropical deforestation provides a significant contribution to anthropogenic increases in atmospheric CO2 concentration that may lead to global warming. Forestation and other forest management options to sequester CO2 in the tropical latitudes may fail unless they address local economic, social, environmental, and political needs of people in the developing world. Forest management is discussed in terms of three objectives: carbon sequestration, sustainable development, and biodiversity conservation. An integrated forest management strategy of land-use planning is proposed to achieve these objectives and is centered around: preservation of primary forest, intensified use of nontimber resources, agroforestry, and selective use of plantation forestry. The information in this document has been wholly funded by the US Environmental Protection Agency. It has been subjected to the agency's peer and administrative review and approved for publication of an EPA document. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.  相似文献   

18.
This study attempts to apply choice experiments with regard to the residential waste disposal system (RWDS) in Korea by considering various attributes that are related to RWDS. Using data from a survey conducted on 492 households, the empirical analysis yields estimates of the willingness to pay for a clean food-waste collection facility, the collection of small items (such as obsolete mobile phones and add-ons for personal computers), and a more convenient large waste disposal system. The estimation results of multinomial logit models are quite similar to those of nested logit models. The results reveal that residents have preferences for the cleanliness of facilities and the collection of small items. In Korea, residents are required to purchase and attach stickers for the disposal of large items; they want to be able to obtain stickers at not only village offices but also supermarkets. On the other hand, the frequency of waste collection is not a significant factor in the choice of the improved waste management program.
Seung-Hoon YooEmail:
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19.
Cross-boundary coordination is a tool for ecosystem management whereby landowners voluntarily coordinate management practices toward economic and/or ecological landscape-scale outcomes (e.g., fiber, invasive species control, habitat). Past research indicates that it may be particularly applicable on landscapes that include small forest landholdings. To explore alternatives by which coordination might occur, we conducted seven focus groups with landowners (n = 51) who actively manage their forests in southwest Wisconsin and northeast Iowa. Focus group participants were presented with three hypothetical alternatives to coordinate with their neighbors; landowners could self-organize, work with a natural resource professional (i.e., forester), or work with an organization to complete a cross-boundary practice. In this article, we focus on the latter two alternatives and the role of two social theories—principal-agent and cooperation—in explaining landowners’ evaluations of these alternatives. Key findings are that (1) cross-boundary coordination has the potential to alleviate problems between landowners and resource professionals inherent to their typical working relationship, and (2) social relationships are a major factor contributing to landowners’ willingness to participate. We posit that cross-boundary coordination offers a non-economic incentive for landowners to work together as it may reduce the uncertainty associated with hiring a resource professional. At the same time, professionals can provide a bridging function among landowners who are unacquainted. To achieve these outcomes and expand the adoption of cross-boundary coordination, we suggest four guidelines. First, foster dialogue among landowners toward shared cognition and oversight. Second, match landowners’ practices and objectives such that there are clear benefits to all. Third, develop relationships through low risk activities where possible. Fourth, do not expect on-going commitments.
Mark RickenbachEmail:
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20.
Land-Use and Land-Cover Change in Montane Mainland Southeast Asia   总被引:12,自引:1,他引:12  
This paper summarizes land-cover and land-use change at eight sites in Thailand, Yunnan (China), Vietnam, Cambodia, and Laos over the last 50 years. Project methodology included incorporating information collected from a combination of semiformal, key informant, and formal household interviews with the development of spatial databases based on aerial photographs, satellite images, topographic maps, and GPS data. Results suggest that land use (e.g. swidden cultivation) and land cover (e.g. secondary vegetation) have remained stable and the minor amount of land-use change that has occurred has been a change from swidden to monocultural cash crops. Results suggest that two forces will increasingly determine land-use systems in this region. First, national land tenure policies—the nationalization of forest lands and efforts to increase control over upland resources by central governments—will provide a push factor making it increasingly difficult for farmers to maintain their traditional swidden land-use practices. Second, market pressures—the commercialization of subsistence resources and the substitution of commercial crops for subsistence crops—will provide a pull factor encouraging farmers to engage in new and different forms of commercial agriculture. These results appear to be robust as they come from eight studies conducted over the last decade. But important questions remain in terms of what research protocols are needed, if any, when linking social science data with remotely sensed data for understanding human-environment interactions.  相似文献   

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