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1.
By 2010, about 25% (180 million ha) of The International Tropical Timber Organization (ITTO) producer countries’ permanent forest estate was being managed using an approved forest management plan (FMP). While the existence of a FMP is often used as evidence of sustainable forest management (SFM), State officials mandated to monitor and verify FMPs’ implementation often lack the technical knowledge and political incentives to assess the changes that have been introduced, notably in terms of harvested volumes and species. Among tropical timber producers, Cameroon is considered to be exemplary for its progressive forest regulatory framework. Here we aim to estimate for the first time in sub-Saharan Africa the causal impact of the implementation of FMPs on harvested volumes, species and carbon stocks. We do so by using a 12-year (1998–2009) unbalanced longitudinal data set of a detailed, official harvesting inventory of 81 concessions in Cameroon. Results provide evidence to the theoretical expectations that for many years many practitioners have had on the implementation of SFM, i.e. that FMPs show a substantial opportunity to reduce carbon emissions from forest while presenting logging companies with acceptable financial trade-offs. We explore the technical and political reasons for our findings and conclude that these analyses are important for countries that are underwriting carbon-related schemes in which they propose to reduce their emissions through the effective implementation of SFM. We also demonstrate that producer countries do record useful information that, when effectively used, can help them to inform their policies and improve their sustainable development strategies.  相似文献   

2.
Recently, goal programming (GP) has been discussed in the literature as an alternative to linear programming, particularly in decision-making environments involving multiple objectives. In this paper we present an overview of the different GP formulations, their assumptions, limitations, and implications for agricultural decision making. Furthermore, a new insight into the interpretation of duality in GP is discussed. The concept of "standardized dual variables" which provides a more meaningful interpretation of shadow prices in GP is introduced. A simple but realistic farm agricultural planning example is used to illustrate the analysis.
Récemment, la technique de programmation appellée "goal programming" ou "GP" a été presentée dans la literature comme une alternative à la programmation Iinéaire, particulièrement dans les situations òu le procés de décision est basé sur plusieurs objectifs simultanés. Dans cet article nous présentons une vue génerale des différentes formes de la "GP;" leurs hypothèses de base. Ieurs limitations, et leurs implications pour le procés de decision agricole, une nouvelle intérpretation de la dualité en "GP" est proposée. En particulier, le concept de "variables duales standardisées" est introduit, ce qui permet une interpretation plus significative des prix de reference en "GP." Finalement. un exemple simple mais réaliste de planification agrcole a l' échelle d' une ferme est pour élucider utilisé l' analyse.  相似文献   

3.
This paper presents a new forest harvest scheduling model taking into account four conflicting objectives. The economic factor of timber production is considered and also aspects related to environmental protection. We also incorporate adjacency constraints to limit the maximum contiguous area where clear-cutting can be applied. The model proposed is applied to a timber production plantation in Cuba located in the region of Pinar del Río. One factor to be taken into account in Cuban plantations is that the forest has a highly unbalanced age distribution. Therefore, in addition to the classical objectives of forest planning, we have the objective of rebalancing age distribution by the end of the planning horizon. Explicitly, the four objectives considered in the model are: (a) obtaining a balance-aged forest; (b) minimizing the area with trees older than the rotation age; (c) maximizing the NPV of the forest over the planning horizon; and (d) maximizing total carbon sequestration over the whole planning horizon. The solution to the proposed model provides a set of efficient management plans that are of assistance in analysing the tradeoffs between the economic and ecological objectives. The model is also applied to randomly generated simulated forests to compare its performance in other contexts. As the problem is a multiobjective binary nonlinear model, a metaheuristic procedure is used in order to solve it.  相似文献   

4.
People have planted trees in rural places with increasing frequency during the past two decades, but the circumstances in which they plant and the social forces inducing them to plant remain unclear. While forests that produce wood for industrial uses comprise an increasing number of the plantations, most of the growth has occurred in Asia where plantations that produce wood for local consumption remain important. Explanations for these trends take economic, political, and human ecological forms. Growth in urban and global markets for forest products, coupled with rural to urban migration, may spur the conversion of fields into tree farms. Government programs also stimulate tree planting. These programs occur frequently in nations with high population densities. Quantitative, cross-national analyses suggest that these forces combine in regionally distinctive ways to promote the expansion of forest plantations. In Africa and Asia plantations have expanded most rapidly in nations with densely populated rural districts, rural to urban migration, and government policies that promote tree planting. In the Americas and Oceania plantations have expanded rapidly in countries with relatively stable rural populations, low densities, and extensive tracts of land in pasture. If, as anticipated, the growing concern with global warming spurs further expansion in forest plantations in an effort to sequester carbon, questions about their social and ecological effects should become more pressing.  相似文献   

5.
Although intensive managed plantations clearly increase the growth and yield of forests several papers refer to declining forest productivity. Therefore in this paper we study the impact of declining forest productivity on the land expectation value and the optimal rotation length. We start from the research by Lu and Chang (1996) and try to fill the gap between the stable site productivity (“best”) and the site mining (“worst”) cases. For that we extend the classical Faustmann model by availability of different recovering technologies. In general the model allows the analysis of the two plantation groups: “mining the site by high productive plantation followed by management of degraded areas” and “high productive plantation and regeneration cycling” with the same comparative static. The model, analysis and comparison with the two extreme cases in Lu and Chang (1996) leads to a detailed understanding of land use management when site productivity decline is possible. Particularly the relation between declining periods with intensive land use and land use alternatives after declining periods with regeneration can be well understood. Findings are: Not ever declining process asks for regeneration. Many declining processes can be stopped at early times by high cash flows after mining periods. Shortenings of the regeneration time can boost site mining intensities.  相似文献   

6.
If there is a strong argument in favour of multifunctional forest management, there is also controversy regarding the types of multifunctionality able to instil virtuous circles across landscapes. Managing forests in such a way that user groups, sustainability practitioners and forestry institutions all agree to, is not easy. For any reliable consensus to occur, via viable landscape design procedures, through which multiple functions (production, environmental protection and recreation) may be coordinated by means of innovative planning, there is a need to negotiate a set of common objectives and shared responsibilities. This paper examines the policy dimensions of multifunctional forest management, and, through an exploratory case study, proposes an approach for cooperative planning and institutional design. The case study involved two parishes in the Minho region of Portugal (Gavieira and Entre Ambos-os-Rios) combining the local communities, the National Park, and local forestry officers. The case study created, developed and validated two scenario storylines through a series of participatory processes (two focus group meetings, one comprehensive workshop, and one expert meeting). One scenario focussed on continuity of the traditional management patterns, with an emphasis on direct goods such as timber and livestock grazing (traditional multifunctionality). The other concentrated on indirect ecological services, such as soil and water protection, as well as carbon sequestration (new multifunctionality). An attempt was also made to implement the scenario storylines through initiating a pilot project in both of the case study areas. However, there were neither robust planning mechanisms nor adaptive governance systems with the capacity to put into place forest management “futures” likely to deliver more sustainable landscape-scale uses in these areas. This paper illustrates the difficulties in forging governance systems that have the capacity and the vision to be able to put sustainable development concepts into practice, even when a coherent package of planning measures are tried out, given a policy setting that is confused, contradictory, and where the “status quo” tends to be given prominence.  相似文献   

7.
The Chinese government applies the term ‘tree crops’ (jingjilin) to a bundle of tree species with uses other than timber production, defining this category as a component of national forest statistics. Tree crops may displace either farmland or forestland, and can be a promising livelihood option for smallholders. The overall impact of this particular policy on natural forest growth remained unanswered. In the general expansion trend of tree cover in southern China, tree crops could compete for land with natural forests, their cultivation may pose environmental trade-offs with natural forest cover. However, in a context of large labor flows from countryside to cities, tree crops could provide promising opportunities for dealing with on-farm labor shortages and generating income for disadvantaged populations remaining in rural communities, then promoting remaining natural forest quality through alternative livelihoods process. There is a knowledge gap to thoroughly investigate tree crops’ impact on natural forest change both conceptually and empirically, especially a mechanism verification of the alternative livelihood hypothesis. Thus, we construct a framework assessing land use competition and alternative livelihood effects together to assess overall impacts of tree crop cultivation on natural forests. Our dataset combines forest resource inventory data and provincial social-economic factors for a panel analysis of contributions to change in natural forest cover, density, and stock in China’s biodiversity-rich southern provinces. Results show tree crop cover is negatively associated with natural forest extent, but positive associated with change in natural forest density, while the relationship with change in natural forest stock is insignificant. Further tests of mechanisms support the hypothesis that tree crops benefit disadvantaged rural populations, providing an alternative livelihood. Defining tree crops as forest in China obscures important patterns, particularly a trade-off between tree crops and natural forest cover and a possible synergy with natural forest density mediated by alternative livelihood processes. Policy makers should enact specific policies to incentivize natural forest recovery in the southern collective forest zone and reconsider the appropriateness of defining tree crops as forest. Concentration and intensification of tree crop production on suitable lands may have the potential to benefit both forests and impoverished populations.  相似文献   

8.
9.
Aspects of governance of non-wood forest products (NWFPs) include institutional rules, stakeholder arrangements, and decision-making processes that govern production systems from access to resources, their use, and to markets. Compared with other forest products, few studies have investigated the governance of NWFPs in European post-socialistic countries transitioning from a planned to a market economy. This study compares institutional frameworks and stakeholder arrangements related to NWFPs in Russia and Ukraine using a case study approach. Both countries have a legacy of top-down forest government, state-owned forests, and rural communities with a long dependence on plant- and animal-based NWFPs. We analysed legal documents for NWFPs in each country and conducted expert interviews with stakeholders from the public, private, and civil sectors involved in the decision-making process of NWFPs. Institutional frameworks for NWFPs in both countries are complex, unclear, and overlap. Multiple legal documents contain restrictions regarding the extraction and sustainability of NWFPs. However, no special laws or policies are solely for NWFPs; all measures are included in legislation that regulates nature conservation and forest management. The government of both countries tends to overlook non-industrial forest use undertaken by marginal local communities, even if economic, social, and cultural values of NWFPs are relatively high for local and regional development. A misfit is observed between legal frameworks and forest companies’ business policies with customary rights. This phenomenon caused a shift to introduce new stakeholder arrangements related to NWFPs as a special type of resource in areas where NWFPs are heavily used both for subsistence and for generating household income by local communities. Landscape approach initiatives such as model forests and biosphere reserves may empower local communities to find means to protect their rights, needs, interests, and values related to NWFPs.  相似文献   

10.
Forest associations (secondary-level institutions that support and represent groups of forest producer communities) play an important and understudied role in promoting community forestry in a multi-level forest governance context in many countries. This role continually evolves to meet new demands from their constituents, with associations diversifying into activities that bring new governance issues, interests, organizational logics and capacity needs. As community forestry in many countries is being integrated into REDD+ national strategies, questions arise regarding new roles for these associations. Through a case study of two forest associations in Quintana Roo, Mexico, this study traces the history and evolution of these associations as they react and adapt to a changing forest sector, uses forest stakeholders’ opinions to assess the associations’ current status and perceived importance of their involvement in the forest sector, and examines how current opinions and historical legacy have shaped their role in REDD+ in Mexico. Results show that association members and outsiders (mostly government stakeholders) hold divergent views of the utility of these organizations. Outsiders’ negative perceptions, as well as the niche that the associations are currently in, is largely determining their limited participation in REDD+ consultation and implementation to date. This is a missed opportunity to engage important allies who still hold high legitimacy in the eyes of the communities that will be the ultimate implementers of REDD+.  相似文献   

11.
Voluntary forest conservation programs offer family forest owners (FFO) financial incentives in exchange for legally-binding land use restrictions and/or management obligations. Protecting family forests in the Catskill Mountains region of New York is an important policy objective, as these watersheds provide clean drinking water to New York City. Multiple methods were used to elicit preferences for forest conservation program attributes and to identify potential barriers to participation. Respondents to a mailed survey were grouped according to the program attribute that most influenced their likely participation into forest conservation programs. Respondents were identified as time-sensitive, payment value-sensitive, rights-sensitive, payment mode-sensitive, or harvest-sensitive. Comparing groups revealed significant differences in age, attitudes towards harvesting trees, income, and importance of timber production. Supplemental qualitative data was collected during three focus groups of survey respondents and analyzed for general themes. Focus group discussions revealed a lack of knowledge about conservation easement programs, reluctance to burden landowners’ children with encumbered land inheritances, concerns for resale values and tax assessment, and a simmering animosity towards New York City’s watershed management efforts. We offer strategies to address these concerns and to design programs that will foster greater participation among FFOs in the region.  相似文献   

12.
Market instruments for environmental governance have a foundation in an economic theorythat claims to be universal and atemporal, but their materialization in practice always takes place in specific socioeconomic and political contexts. The Brazilian trade in forest certificates (CRA) is a new market instrument that allows farmers that have deforested illegally prior to 2008 to become compliant by acquiring certificates from other farmers that conserve a forest area beyond legal requirements. Even though the CRA market has been praised as an innovative environmental policy, it is still unclear whether it will be implemented even after more than two decades of political debate, congressional approval of legislation and substantial investments in new supporting systems. This research paper aims to analyze the materialization of this market by reconstructing how policy participants form advocacy coalitions (i.e. environmental protection, market viability and agricultural consolidation) to advance their interests. Our results show that advocacy coalitions filter (i.e. absorb, reject or transform) new ideas, experiences and knowledge in order to influence the regulations for forest certificate trading. In doing so, they often combine positions, form new alliances and merge with other advocacy coalitions in accordance with the interests of their constituents. These fluid allegiances within and between coalitions explain why market materialization remains ambiguous and unlikely to become operational in the near future.  相似文献   

13.
One-third of the forestland in the U.S. is owned by 10.4 million family forest owners. Their collective decisions have a great impact on the sustainability of forest landscape across the country. Public policies and programs for encouraging landowners to properly manage their land include cost-share, forest certification, and conservation easements. However, to date, less than 6% of the family forest owners have participated in a cost-share program, less than 1% have certified their land, and less than 2% have an easement. By analyzing data from USDA Forest Service's National Woodland Owner Survey, we examined the characteristics of family forest owners who had participated in these programs and identified strategies to capitalize on these landowner characteristics to improve current programs and attract a wider range of participants. We found that family forest owners with larger land holdings were more likely to participate in all three types of programs. Obtaining forest management information or advice was important for program participation; however, the effects differed depending on the types of programs and the sources of information. Income was not significant in predicting participation in cost-share programs, implying family forest owners from lower-income strata were not more likely to use cost-share program. The results also suggest the importance of targeting the right audience when promoting forest certification programs, namely those who are participants of cost-share programs, own forestland for reasons other than farming or ranching, and plan to harvest sawlogs or pulpwood in the future. Age was not significant in any of the empirical models. This result is particularly intriguing in the context of conservation easement, considering recent discussions about the high cost of dying unprepared and the potential for promoting conservation easement as part of estate planning among older family forest owners. Finally, few variables were significant in the model predicting landowner decision about donating or selling an easement, suggesting the easement decision is very different from cost-share and forest certification decisions and further efforts are needed to understand the dynamics of this increasingly popular conservation policy tool. In summary, this study provides a better understanding of the relationship between program participation and the demographics, attitudes and behaviors of family forest owners. This understanding contributes to the development of outreach strategies for improving landowner interest in forest conservation programs.  相似文献   

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