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Participation has been widely touted as “the answer” to a number of problems facing agroforestry research programs. It is not enough, however, to involve rural people as workers and informants in research endeavors defined by outsiders. A truly collaborative approach will depend upon our ability to broaden our definitions of research and participation, to accommodate a wide spectrum of land users and local knowledge, and to expand our repertoire of research methods. This paper presents a critique of facile approaches to participation, outlines a more inclusive framework for who participates on what terms, and reviews a variety of methods that address the complex realities of rural life and landscapes. The final section of the paper suggest a multi-institutional model that combines the complementary strengths of several types of organizations in participatory field research.  相似文献   

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Seven different activities constitute tree domestication: (1) manipulation of tree populations by silvicultural practices; (2) enhancement of site productivity; (3) control of destructive agents; (4) evolution of trees under natural selection; (5) semi-natural selection for survival in the socio-agricultural circumstances in which trees are grown; (6) conscious human selection for desired characteristics; and (7) correlated response to selection (which usually involves reduction of those plant parts that are not desired). Each of these activities is discussed, and its contribution to the present makeup of tree populations used for agroforestry is considered.Although tree domestication has been practiced by farmers for many centuries, selection and breeding programs for multipurpose agroforestry trees have existed for only the past thirty years. Some of the problems faced by existing tree improvement programs are discussed; these include: multiplicity of usable species, great demand for multipurpose trees (MPTs), existence of improvement programs with few species, difficulty of combining desired traits in a multipurpose ideotype, high cost and slow progress with present methods, and the fate of improved material introduced on farms. Among the solutions considered is more involvement of farmers in the process of selection, testing, and propagation of MPTs. The possible use of species mixtures also holds promise.  相似文献   

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Summary Some pertinent results and views from the earlier history of lignin chemistry, pointing to the importance of the arylpropane skeleton, are outlined. Later development, beginning with the dehydrogenation theory and experimental studies on the dehydrogenative polymerization of p-hydroxycinnamyl alcohols, is then reviewed. Finally, recent degradative work resulting in a detailed picture of lignin structure is discussed.  相似文献   

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State-of-the-art of agroforestry research and education   总被引:1,自引:0,他引:1  
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Australia's forests have been characterized by a history of contestation and conflict since British colonization in 1788. This paper adopts a “pathways to sustainability” approach to review Australia's forest governance models, which are strongly tenure-dependent, and generally vary between sub-national jurisdictions; only climate change-related policies, which are in a state of considerable flux, apply to all forests. Consequently, pathways to sustainability are defined largely in terms of the dominant purpose of particular tenures, and are now little-integrated across institutions, landscapes or tenures. Three decades of trialing devolved models of natural resource governance have effectively been abandoned, as have many of the initiatives intended to support development of a more diverse and more integrated ‘forestry’ sector. While the near-term prospects for sustainability of Australia's forests in anything more than the narrowest sense are poor, there are both knowledge-based and historical institutional foundations from which more substantive progress towards sustainability could be realized. This progress will need to be founded on approaches to policy development and implementation that recognize and accommodate the plurality of interests in forests, that enhance coordination and integration between institutions and across landscapes, and that empower and enable the diverse communities of interests in forests.  相似文献   

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从木材科学研究的内容出发,分析了我国木材科学研究的现状,并对我国木材科学研究的发展趋势做了深入的探讨,指出今后我国木材科学研究将向着多学科、更先进的研究方向发展。  相似文献   

11.
The BAIF Development Research Foundation initiated an agroforestry extension project in Pune District, India in 1984, following earlier on-station research on leuceana-based alley-cropping systems for fodder. In extension meetings, farmers expressed a strong preference for planting a wide range of multipurpose trees on farm bunds and borders rather than single-species alley-cropping. Researcher-managed trials of proposed multipurpose species grown with crops were initiated, but were of limited value. An alternative approach to research was begun in 1988. This approach included a survey of agroforestry practices established by farmers through extension, and collection of data on crop yields by distance from the tree line from a sample of these plots. Research methods are described and modifications suggested for improving the quality of this type of extension-based research.  相似文献   

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The rapid appraisal and farmer selection procedures, preceding the establishment of over fifty agroforestry research trials on farms in Talamanca, Costa Rica are described. The highest probability of success and impact of these long-term collaborative trials is obtained by selecting innovative, experienced, motivated and locally respected farmers. The methodological lessons learned from implementing three types of researcher managed trials (shade-cacao; black pepper on living support posts; timber production in boundary lines) are discussed. The importance of fitting farmer selection criteria to project objectives, experimental designs to on-farm limitations, and project goals to farmers' goals, are emphasized.  相似文献   

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Because of the relative dearth of scientific information in agroforestry, monitoring and evaluation of agroforestry technologies in development projects plays an important role in the development and improvement of technical extension recommendations. To identify appropriate methodologies, ICRAF conducted in 1988–89 a review of agroforestry technology monitoring and evaluation in 166 projects worldwide, of which 108 responded. Almost 80% of these were involved in technology evaluation. Many extension projects were conducting research to test technologies on-farm or on research plots. Technology evaluation by projects focused on the biological of trees, often with inadequate consideration of the technology context. Few projects seemed to use farmer assessment in evaluation. Recommendations are made for an effective evaluation process and selection of appropriate methods and variables to be assessed by projects. Methods should be selected according to the availability of resources and should favour collaborative or collegial interaction between farmers and project staff.  相似文献   

15.
Although tidal floodplain forests represent the oldest commercial logging frontier in the Amazon, tree demography analyses are lacking. Consequently, the accurate evaluation of impacts of past use and the development of ecologically sound forest management has lagged. To address that gap, we combine matrix model methods with data from interviews with tidal floodplain smallholders regarding land use and ecological knowledge. Here we examine the population dynamics of 8 common tidal floodplain species and explore the link between species population ecology and past, present, and future timber use.Despite the generally high timber stocks due to the dominance of Mora paraensis, these tidal floodplain forests offer challenges to management similar to those seen in tropical forests elsewhere, including low recruitment and species-specific tree growth rates, population densities and size distributions. Furthermore, species population ecology and survey results indicate that the long legacy of forest use in the tidal floodplain forests will influence the future of forest use and management, negatively impacting some species (e.g., Virola surinamensis) while likely benefiting others (e.g., M. paraensis). The observed diameter distributions of species least harvested in the past (e.g., M. paraensis, Licania heteromorpha) follow those derived from stable stage distributions. For other historically harvested species (e.g., Carapa guianensis, V. surinamensis), a larger number of harvest-sized trees for most species would be expected under unlogged conditions, a result corroborated by survey results indicating that maximum log size of long-used timber species has decreased over the past decades.While timber extraction in the Amazon Estuary has endured for centuries, our results suggest long-term timber use does not necessarily entail sustainability; a long history of timber harvesting can also indicate a gradual process of resource depletion as preferred species are sequentially exhausted. If current practices are left unchanged, the prospects for long-term management are likely to decrease further as the densities of preferred high-value species (C. guianensis, V. surinamensis, P. filipes) fall to levels that make management economically unattractive.  相似文献   

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We examine almost a century of research activity conducted at Canada's two National Research Forests describing the contributions of long-term study sites and experiments in North America to forest science. The establishment and history of the Petawawa Research Forest and the Acadia Research Forest are outlined, both managed by the Canadian Forest Service, Natural Resources Canada. Examples are given of past lessons learned from these forests, today's relevance of these research sites, and some perspectives on their value into the future. Specific examples illustrate how a study initially set up for a specific purpose provided answers through time to new and emerging topics that were not foreseen when the study began.  相似文献   

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García-Barrios  L.  Ong  C.K. 《Agroforestry Systems》2004,61(1-3):221-236

During the 1980s, land- and labor-intensive simultaneous agroforestry systems (SAFS) were promoted in the tropics, based on the optimism on tree-crop niche differentiation and its potential for designing tree-crop mixtures using high tree-densities. In the 1990s it became clearer that although trees would yield crucial products and facilitate simultaneous growing of crops, they would also exert strong competitive effects on crops. In the meanwhile, a number of instruments for measuring the use of growth resources, exploratory and predictive models, and production assessment tools were developed to aid in understanding the opportunities and biophysical limits of SAFS. Following a review of the basic concepts of interspecific competition and facilitation between plants in general, this chapter synthesizes positive and negative effects of trees on crops, and discusses how these effects interact under different environmental resource conditions and how this imposes tradeoffs, biophysical limitations and management requirements in SAFS. The scope and limits of some of the research methods and tools, such as analytical and simulation models, that are available for assessing and predicting to a certain extent the productive outcome of SAFS are also discussed. The review brings out clearly the need for looking beyond yield performance in order to secure long-term management of farms and landscapes, by considering the environmental impacts and functions of SAFS.

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Planning agroforestry research programs requires the participation of people from many disciplines. They may have different interests in allocating financial resources for research purposes and, therefore, the decision-making is complex. Guidelines are needed to improve the decision-making process. Such guidelines may include a list of weighted criteria identified by experts through group processes. This study used a qualitative approach (the Delphi method) to identify criteria to be used when planning agroforestry research programs in the developing countries. The panel of respondents was comprised of agroforestry experts who have experience and expertise in the developing countries. Fourteen (14) criteria were identified in questionnaire 1. These criteria were ranked in questionnaires 2 and 3. A Friedman test of analysis of variance followed by a Mann-Whitney U test of pairwise comparison produced four groups of criteria: group 1, the most highly ranked, comprises local people's needs, sustainability, adoptability and research quality; group 2 includes existing systems and economic criteria; group 3 encompasses biophysical effects, institutional capabilities, partnership and transferability; and group 4, the least ranked, includes diversity of products, tree/crop interface, flexibility and species selection. A Kruskal-Wallis test on each criterion and several respondent characteristics showed that the respondent characteristics of current work, highest degree held, ecosystem experience, geographic area of experience, and number of years experience influenced respondent criteria rankings. The test was not significant for background and respondent origin characteristics.  相似文献   

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Agroforestry research in academia and government and non-governmental agencies began by focusing on biophysical aspects. As this science represents a series of practices implemented by individual farmers, it requires in-depth social and economic analyses to assess economic feasibility of agroforestry systems, factors influencing the adoption of agroforestry, monitor the relevance and effectiveness of investigations, and guide future research efforts. This study presents literature dealing with socioeconomic issues in agroforestry research from interdisciplinary peer-reviewed journals, book chapters, and gray literature from 1992 to 2002. Over 500 publications were analyzed to determine relative dominance of geographical regions, types of analyses, agroforestry technologies, and socioeconomic issues. Trends were examined over time and by region. Overall, the body of literature exhibits an increasing trend toward regional and analytical diversity over time. Some deficiencies of regional and thematic nature were observed, which included underrepresented temperate regions and technologies such as riparian buffers, as well as only a small number of papers dealing with gender and property rights. These suggest opportunities for future investigations.  相似文献   

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Agroforestry trees are attacked by a wide spectrum of insects at all stages of their growth just like other annual and perennial crops. Pest management in agroforestry has not received much attention so far, but recent emphasis on producing high value tree products in agroforestry and using improved germplasm in traditional systems, and emergence of serious pest problems in some promising agroforestry systems have increased awareness on risks posed by pests. Insects may attack one or more species within a system and across systems in the landscape, so pest management strategies should depend on the nature of the insect and magnitude of its damage. Although greater plant diversity in agroforestry is expected to increase beneficial arthropods, diversity by itself may not reduce pests. Introduction of tree germplasm from a narrow genetic base and intensive use of trees may lead to pest outbreaks. In simultaneous agroforestry systems, a number of factors governing tree—crop—environment interactions, such as diversity of plant species, host range of the pests, microclimate, spatial arrangement and tree management modify pest infestations by affecting populations of both herbivores and natural enemies. Trees also affect pest infestations by acting as barriers to movement of insects, masking the odours emitted by other components of the system and sheltering herbivores and natural enemies. In sequential agroforestry systems, it is mostly the soil-borne and diapausing insects that cause and perpetuate damage to the common hosts in tree—crop rotations over seasons or years. An integrated approach combining host-plant resistance to pests, exploiting alternative tree species, measures that prevent pest build up but favour natural enemies and biological control is suggested for managing pests in agroforestry. Species substitution to avoid pests is feasible only if trees are grown for ecological services such as soil conservation and low value products such as fuelwood, but not for trees yielding specific and high value products. For exploiting biological control as a potent, low cost and environmentally safe tool for pest management in agroforestry, research should focus on understanding the influence of ecological and management factors on the dynamics of insect pest-natural enemy populations. Scientists and policy makers in national and international institutions, and donors are urged to pay more attention to pest problems in agroforestry to harness the potential benefits of agroforestry.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

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