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1.
The potentialities of agroforestry are generally investigated through their biophysiological phenomena, cost–benefit analysis,
and possible impact upon poverty reduction. There have been inadequate studies on the actual impacts of agroforestry intervention
on small landholders and of farmers' attitudes toward these agroforestry programs. Drawing upon the findings of an empirical
study, this article explores the effects of small-scale agroforestry on upland community development in the Chittagong Hill
Tracts, Bangladesh. More specifically, the study clarifies the merits and demerits of different agroforestry systems as perceived
by farmers, their impacts on the rural economy and the environment, farmers' attitudes toward the adoption of agroforestry,
and impacts of various government policies. Field data were collected by administering questions to 90 randomly selected smallholders
of the Upland Settlement Project (USP), as well as from project staff. The research tools employed were semistructured interviews,
group discussions, and uncontrolled observations. The results indicated that the agroforestry interventions have in fact increased
farmers' income through employment and the selling of farm products, as well as by improving the ecological conditions of
these areas through reduction of soil erosion, increasing tree coverage, and maintaining soil fertility. The adoption of different
agroforestry systems was governed mainly by the farmers' interests in following these techniques, their ability to cultivate
the land in the prescribed manner, and the market demand for their products. The major obstacles that prevented increased
agroforestry improvements included lack of confidence in new land-use systems, inappropriate project design (e.g., top-down
innovation approach), and policy issues regarding land tenure. Recommendations are proposed to strengthen social capital in
local organizations to enhance the livelihoods of the upland communities. 相似文献
2.
In global terms, European farms produce high yields of safe and high quality food but this depends on the use of many off-farm inputs and the associated greenhouse gas emissions, loss of soil nutrients and other negative environmental impacts incur substantial societal costs. Farmers in the European Union receive support through a Common Agricultural Policy (CAP) that comprises direct payments to farmers (Pillar I) and payments related to rural development measures (Pillar II). This paper examines the ways in which agroforestry can support European agriculture and rural development drawing on the conclusions of 23 papers presented in this Special Issue of Agroforestry Systems which have been produced during a 4-year research project called AGFORWARD. The project had the goal of promoting agroforestry in Europe and focused on four types of agroforestry: (1) existing systems of high nature and cultural value, and agroforestry for (2) high value tree, (3) arable, and (4) livestock systems. The project has advanced our understanding of the extent of agroforestry in Europe and of farmers’ perceptions of agroforestry, including the reasons for adoption or non-adoption. A participatory approach was used with over 40 stakeholder groups across Europe to test selected agroforestry innovations through field trials and experiments. Innovations included improved grazing management in agroforestry systems of high nature and cultural value and the introduction of nitrogen fixing plants in high value timber plantations and olive groves. Other innovations included shelter benefits for arable crops, and disease-control, nutrient-retention, and food diversification benefits from integrating trees in livestock enterprises. Biophysical and economic models have also been developed to predict the effect of different agroforestry designs on crop and tree production, and on carbon sequestration, nutrient loss and ecosystems services in general. These models help us to quantify the potential environmental benefits of agroforestry, relative to agriculture without trees. In view of the substantial area of European agroforestry and its wider societal and environmental benefits, the final policy papers in this Special Issue argue that agroforestry should play a more significant role in future versions of the CAP than it does at present. 相似文献
3.
Determinants of farmers' adoption and adaptation of alley farming technology in Nigeria 总被引：1，自引：0，他引：1
Understanding the factors affecting framers' adoption of improvedtechnologies is critical to success of implementing agroforestry
developmentprograms. This paper evaluated the determinants of farmers' decisions to adoptand adapt alley farming technology
and its variants in the farming systems ofNigeria, using econometric Logit models. Eleven variables were significant inexplaining
farmers' adoption decisions. The model results show that farmercharacteristics that influenced adoption included the gender
of the farmer,contact with extension agents, years of experience with agroforestry and tenancystatus in the village. Economic
factors, proxied by village-levelcharacteristics that condition resource use incentives, were also significant.These variables
include the extent of village land pressure, extent of erosionintensity, village fuel wood pressure, importance of livestock
as an economicactivity in the village and the distance of the village locations from urbancenters. The paper showed that farmers
are already making significantmodifications to the conventional alley farming technology introduced byscientists. The two
most important modifications were the introduction of fallowperiods into the conventional system and changes in the pruning
regime of thesystem. Model results showed that human capital variables were significant inexplaining farmers' decisions to
adapt and modify the technology. Farmereducation and family size significantly influence the choice of pruning regime.Farmers'
age, education, intensity of erosion in the farmers' village, andfarmers' land availability significantly influence whether
or not fallowperiod is introduced into the conventional system. To promote greater adoptionof agroforestry alternatives to
slash-and-burn agriculture, particular attentionshould be placed on the use of appropriate socioeconomic characterization,
tobetter target technologies to areas with higher adoption potential.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
4.
Institutional and policy issues are now recognized as high priority items in agroforestry research. However, such studies based on actual field experiences seldom seem to have been undertaken. To help address this deficiency, a study was undertaken in Ecuador to evaluate institutional and policy impacts on agroforestry dissemination using two field projects as case studies.The projects were in contrasting ecological locations: the Amazonian lowlands (the Coca Agroforestry Project), and the Andean highlands (the PROMUSTA project). The impact of policy and institutional constraints (such as land tenure, research and extension support, marketing and pricing, and credit) on the implementation of these projects was assessed based on interviews with farmers and project officials as well as analyses of secondary data. The Coca project was found to be adversely impacted by the lack of extension, product marketing, and credit availability. The principal institutional constraints for the Andean project included legal obstacles to farm-land procurement, inadequate extension, little state-financial assistance, and limited affordable credit. The relevance of these issues was location specific: while access to land was not a serious constraint in the lowlands, it was a major issue in the highlands.The study validates the premise that policy and institutional evaluations should become an essential component of design and implementation of agroforestry projects. Although the components of a sound policy framework might be similar in most developing-country situations, it may not be possible to evolve universally applicable procedures for agroforestry-policy formulation because of the location-specificity of the promoted systems and the institutional issue related to their adoption.Florida Agricultural Experiment Station Journal Series No. R-03861. 相似文献
5.
《Journal of Sustainable Forestry》2013,32(3-4):39-51
Summary Finding sustainable land-use systems within the Panama Canal Watershed will be necessary for future management by the Panamanian government. Agroforestry is a land-use option for small-scale farmers living within the Watershed that can help achieve the goals of both conservation and productivity. This case study qualitatively evaluates current agroforestry projects in the Canal Watershed using an analytical framework based on other evaluations of agroforestry systems in Central America. Designated criteria for the analysis include: management objectives, project life span, incentives, technology, economic feasibility, community involvement, and extension. These factors can present obstacles to wide-scale adoption of agroforestry systems by small-scale farmers, thus preventing the realization of associated benefits of agroforestry. The analysis of the three field sites visited in March 1998 is followed by recommendations for expanding agroforestry practices among farmers in the Watershed. 相似文献
6.
Bohdan Lojka Jana Lojkova Jan Banout Zbynek Polesny Daniel Preininger 《Agroforestry Systems》2008,72(1):27-39
As traditional slash-and-burn systems with prolonged fallow periods are no longer feasible in most parts of the tropics, improved
agroforestry systems have high potential to increase the productivity of farming systems and sustain continuous crop production.
Our objective was to assess biophysical and economic performance of planted leguminous tree fallow (using Inga edulis) compared to the traditional slash-and-burn farming system, practiced by farmers on fields infested with noxious weedy grass
Imperata
brasiliensis around the city of Pucallpa, Peru. An existing agroforestry model SCUAF was used to predict biophysical factors, such as
changes in soil characteristics and farm outputs (crop and tree yield). While a cost–benefit analysis spreadsheet, which uses
the output from SCUAF and economic data on input/output levels and prices, calculates economic performance of the systems.
The Inga fallow system can provide improvements to a range of soil biophysical measures (C, N, P content). This enables higher levels
of farm outputs to be achieved (higher cassava yields). However, for smallholders the improved system must be more economically
profitable than the existing one. At prices currently encountered, the Inga fallow system is more profitable than the Imperata fallow system only in the long-term. In adopting the Inga fallow system, smallholders will incur lower profits in the first years, and it will take approximately 10 years for smallholders
to begin making a profit above that achievable with the Imperata fallow system. Unless smallholders are capable of accepting the lower profitability in first years, they are less likely
to adopt the new system. 相似文献
7.
The farming system and traditional agroforestry systems in the Maya community of San Jose, Belize 总被引：3，自引：0，他引：3
Shifting slash-and-burn agriculture is likely one of the main causes of forest degradation in southern Belize. Although many development projects have attempted to reduce the impacts of agriculture on the tropical rainforest, the situation is still a cause for concern. A study of the farming system of the San Jose Maya community was therefore carried out to examine agricultural production in its social, cultural, economic, and political context. Results demonstrate that agricultural production contributes to forest degradation because of the limited availability of agricultural land, the low level of investment in agricultural production, the land tenure system, limited marketing opportunities, and the exclusion of Mayas from the country's political and economic domains. Agroforestry could, however, offer a partial solution to the problem of forest degradation. Three types of traditional agroforestry systems are practised in San Jose: the milpa (a slash-and-burn agriculture system), cacao (Theobroma cacao) cultivation under shade trees, and the homegarden. These traditional agroforestry systems almost entirely meet a family's needs for food and wood, and generate at least 62% of family income. Improving the productivity of these systems could help to reduce pressure on the forest in southern Belize.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
8.
In the subsistence-agricultural region of eastern Zambia, less than 10% of the households have adequate supply of maize (Zea mays L.), the staple food, throughout the year. A major constraint to increasing crop production in the region is poor fertility
status of the soil. In order to address this problem, improved fallow has been introduced as a technology for improving soil
fertility within a short span of two to three years. Farmers have been testing the technology and a number of empirical studies
have been undertaken over the years to identify the factors influencing farmers' decision to adopt the technology. This paper
presents a synthesis of the results of adoption studies and highlights generic issues on the adoption of improved fallows
in Zambia. The synthesis indicates that farmers' decision on technology adoption does not have a simple directed relationship
of some technological characteristics only, but constitutes a matrix of factors including household characteristics, community
level factors, socioeconomic constraints and incentives that farmers face, access to information, local institutional arrangements
and macro policies on agriculture. The adoption of improved fallows is not strictly speaking a binary choice problem but a
continuous process in which farmers occupy a position along a continuum in the adoption path. Further, adoption of improved
fallows may not take place in a policy vacuum but needs to be facilitated by appropriate and conducive policy and institutional
incentives. Several questions and issues that require further study emerge from the synthesis. These include determination
of the relative importance of the factors in the adoption matrix, identification of the conditions under which farmers use
a combination of inputs and their profitability under changing price scenarios, exact definition to delineate between `non-adopters',
`testers' and `adopters' of agroforestry technologies, and understanding the impact of cash crop farming in farmers' adoption
decisions of improved fallows (where off farm opportunities exist). Further, there is a need to determine the inter-relationship
between household poverty, labor availability and the adoption of improved fallows and, to evaluate a combination of policy
interventions at both national and local level to promote the adoption of agroforestry-based soil fertility management.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
9.
To meet raw material requirements, Wimco, the biggest manufacturer of matches in India, has been promoting poplar-based agroforestry through an agroforestry project since 1984 approved by the National Bank for Agricultural and Rural Development (NABARD) in the northern region of India. This study aims at evaluating the performance of poplar-based agroforestry in terms of income, employment and environmental impact from the farmers' perspective. Poplar-based agroforestry is economically viable and more profitable than many of the crop rotations followed in the study area. This land-use system is also capable of providing employment opportunities on farms. Sensitivity analyses indicate that this system is not highly risky. However, costs charged by Wimco for technical advice substantially reduce the income from poplar plantation. With agroforestry experience, farmers can expect high dividends in subsequent rotations. Life-time matrices developed through group interviews are useful for thorough economic analyses of agroforestry projects, particularly in cases where data over a period of time are not available.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
10.
Historical development of agroforestry in China 总被引：3，自引：0，他引：3
In China both agriculture and agroforestry originated in forests and developed side by side from their very beginnings. As revealed by archaeological evidence from ancient times, ancestral Chinese inhabited forests where they sheltered themselves from external hazards and lived on the edible parts of plants and animals through hunting and gathering activities.As early as the New Stone Age (7000–8000 years B.C.), fire was commonly used to burn the forests for slash-and-burn cultivation, which is a primitive form of agroforestry. Along with the rapid growth of population, the annexing of tribes, the collapse of clan society and the development of the slavery system, the nomadic mode of slash-and-burn farming evolved into settlement farming in the Xia Dynasty (2000-1600 B.C.). Peasants then engaged in settled cultivation.During the Shang and West Zhou Dynasty (1600-800 B.C.), perpetual settlement farming encouraged the development of private land-ownership. Peasants planted trees in or around the crop fields and grew fruit plants, vegetables and farmed domestic animals in their home yards for self-sufficiency. Since then, various forms of agroforestry have gradually developed and laid the fundamental framework of the Chinese small-farming economy for more than 3000 years.There has been a rapid growth of population in China over since the 1950s. At the same time, the area of arable land has decreased drastically and the environment has degraded rapidly as industrial development has taken place. The traditional labour-consuming and ineffective agroforestry management practices have not adapted to the current situation. In view of economic, ecological and social benefits, conversion of mono-biological production into a trinity system of agriculture, processing and marketing is suggested and planned experimentally. Such a management system, known as modern agroforestry, could be very beneficial to the development of modern China's rural economy and environmental conservation. 相似文献
11.
《Journal of Sustainable Forestry》2013,32(1-2):115-123
Abstract Agricultural expansion by smallholder producers has been identified by management agencies as one of the main threats to the ecological integrity of La Amistad Biosphere Reserve, in Panama and Costa Rica. Promotion of cacao agroforestry has been proposed as a way to reduce the need for farmers to clear new land within the reserve. In order to realize this goal, the larger cultural, economic, and political forces that motivate agricultural expansion need to be examined, looking beyond the smallholder practices that are the immediately apparent causes of ecological degradation. The four main assumptions behind the proposal to promote smallholder cacao production in the buffer zone are explored: (1) cacao agroforestry is an ecologically benign agricultural system; (2) if cacao production were more financially viable, ecologically degrading activities, such as cattle grazing, would decrease; (3) migrants from other areas are primarily responsible for clearing land on the eastern side of the park; and (4) direct intervention at the smallholder level is the most effective means of preventing agricultural expansion. Our analysis demonstrates that while cacao agroforestry is an ecologically appropriate production system for the buffer zone of the park, price and production stabilization is important for assuring adoption by smallholders. We also suggest that both indigenous and migrant groups are responsible clearing forest for agriculture and that a more useful distinction for managers to make is between clearing enacted as part of sustainable vs. unsustainable management regimes. Finally, we recommend that the impact to the biosphere reserve caused by large-scale cattle and banana production not be overlooked. 相似文献
12.
G. Andrew Stainback Michel Masozera Athanase Mukuralinda Puneet Dwivedi 《Small-Scale Forestry》2012,11(3):285-300
The perception of Rwandan government officials, NGOs, and extension specialists about smallholder agroforestry adoption as a strategy for smallholder farmers in Rwanda was investigated using a strengths, weaknesses, opportunities, and threats analysis framework combined with the analytical hierarchy process. Results indicate that smallholder agroforestry is viewed positively as a suitable strategy for Rwandan smallholder farmers. The most important positive features were the potential for increased agricultural output from agroforestry and a favorable policy environment in Rwanda supporting sustainable agriculture. Results also indicate that there needs to be better coordination of various efforts to promote agroforestry and stronger extension services for smallholder farmers. Carbon offset markets and other environmental service markets were seen as a potential opportunity for smallholder agroforestry. However, the results also indicate that there is substantial uncertainty and skepticism concerning how such markets would benefit smallholder farmers who adopted agroforestry. 相似文献
13.
E. T. Craswell A. Sajjapongse D. J. B. Howlett A. J. Dowling 《Agroforestry Systems》1997,38(1-3):121-137
Steeply sloping lands are widespread in the tropics. An estimated 500 million people practice subsistence agriculture in these
marginal areas. Continued population growth has led to the intensified cultivation of large areas of the sloping lands, exacerbating
the problem of soil erosion. Although research shows that alley cropping and other contour agroforestry systems can stabilize
the sloping lands, these systems have not been widely adopted by farmers.
The Framework for Evaluating Sustainable Land Management (FESLM) has been tested in sloping land areas in the Philippines.
Sustainable land management must be productive, stable, viable, and acceptable to farmers, while protecting soil and water
resources. Farms on which contour hedgerow intercropping has been adopted meet the multifaceted requirements of FESLM, whereas
the farmers' current practice does not. Appropriate land management measures for particular locations depend on a complex
suite of social, economic, and biophysical factors, and need to be developed in participation with farmers.
The role of agroforestry in sustainable management of sloping lands is the subject of networks coordinated by the International
Board for Soil Research and Management (IBSRAM) in seven countries in Asia (ASIALAND) and four countries in the Pacific (PACIFICLAND).
We review selected outcomes from a wealth of network data. From these results the following conclusions about the sustainability
of various agroforestry systems for sloping lands can be drawn:
• In the Pacific, soil loss from sloping lands due to water erosion under farmers' current practices is episodic, unpredictable,
and possibly not severe;
• Agroforestry systems that utilize legume shrubs, fruit trees, coffee (Coffea spp.) or rubber (Hevea brasiliensis) provide
useful economic returns, but are not an essential component in terms of soil protection because grass or pineapple (Ananas
comosus) planted on the contour are equally effective in reducing erosion;
• Agricultural intensification will lead to nutrient mining, reduction of aboveground biomass, declining yields, and less
soil protection unless external sources of nutrients are used;
• nitrogen can be effectively supplied using legumes;
• Cash derived from hedgerow trees and/or shrubs may providean incentive for their adoption by farmers, as well as funds to
purchase external inputs such as fertilizers;
• Labor may be a major constraint to the adoption of complex agroforestry systems.
We also discuss the information management systems required to effectively manage and utilize the extensive sets of experimental
and indigenous data being accumulated. We believe such information systems can facilitate technology transfer across and between
regions, and improve the efficiency of research into agroforestry and other land-management approaches.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
14.
相对于我国退耕还林工程,农区林业的优势在于:经营模式多样,农民经营风险低,行为自主性较强,为农村剩余劳动力(特别是妇女)提供更多就业机会,政府干预较少。我国退耕还林工程应该学习农区林业的成功经验,从政策上做出调整,建立促使农民积极参与的激励机制,并减少政府的直接干预,以降低政策成本。 相似文献
15.
J. E. M. Arnold 《Agroforestry Systems》1983,1(4):299-311
Economic benefits that can accrue to the small farmer from incorporating trees in his farm system, and the economic constraints and costs he may face in doing so, are reviewed. Various economic considerations other than cash outlays and incomings, such as impact of risk, need to be taken into account. Issues are discussed that can arise in identifying, designing and implementing projects intended to help farmers to capture the economic potentials of agroforestry and to avoid or remove related economic impediments. Correct understanding of the factors which will affect the success of project interventions, valuation of the costs and benefits of trees as perceived by the farmer rather than by outsiders, distributional and equity issues, and identification of operational measures to ensure tangible short-term economic benefits are highlighted. The need for giving priority to research into the economic impacts of agroforestry practices on small farmer situations is stressed. 相似文献
16.
G. Moreno S. Aviron S. Berg J. Crous-Duran A. Franca S. García de Jalón T. Hartel J. Mirck A. Pantera J. H. N. Palma J. A. Paulo G. A. Re F. Sanna C. Thenail A. Varga V. Viaud P. J. Burgess 《Agroforestry Systems》2018,92(4):877-891
Land use systems that integrate woody vegetation with livestock and/or crops and are recognised for their biodiversity and cultural importance can be termed high nature and cultural value (HNCV) agroforestry. In this review, based on the literature and stakeholder knowledge, we describe the structure, components and management practices of ten contrasting HNCV agroforestry systems distributed across five European bioclimatic regions. We also compile and categorize the ecosystem services provided by these agroforestry systems, following the Common International Classification of Ecosystem Services. HNCV agroforestry in Europe generally enhances biodiversity and regulating ecosystem services relative to conventional agriculture and forestry. These systems can reduce fire risk, compared to conventional forestry, and can increase carbon sequestration, moderate the microclimate, and reduce soil erosion and nutrient leaching compared to conventional agriculture. However, some of the evidence is location specific and a better geographical coverage is needed to generalize patterns at broader scales. Although some traditional practices and products have been abandoned, many of the studied systems continue to provide multiple woody and non-woody plant products and high-quality food from livestock and game. Some of the cultural value of these systems can also be captured through tourism and local events. However there remains a continual challenge for farmers, landowners and society to fully translate the positive social and environmental impacts of HNCV agroforestry into market prices for the products and services. 相似文献
17.
《Journal of Sustainable Forestry》2013,32(2):63-85
Abstract Soil erosion poses economic and environmental concerns in many tropical uplands. Agroforestry has been proposed as a sustainable land use that can mitigate soil erosion and promote the economic welfare of small farmers. To evaluate such claims, we must (a) develop a composite measure of effectiveness, such as a soil conservation index, and (b) define it in terms understood by the farmers who ultimately choose to adopt and implement agroforestry. We construct an empirical soil conservation index as a weighted average of farmer perceptions of four soil attributes and develop a statistical model of soil conservation benefits of agroforestry by using survey data from the Philippines. Accounting for self-selection bias, we evaluate the soil conservation benefits by testing the correlation between the index and the level of agroforestry adoption. Our estimated model shows that agroforestry can generate 15-20 percent soil conservation for the typical small farmer. We offer several methodological, practical, and policy insights. Because many farmers in developing countries face informational and capital constraints, our study suggests that public policies should support smallholder agroforestry, a type of “natural investment” in soil capital, to generate private and public benefits. 相似文献
18.
Francesca Camilli Andrea Pisanelli Giovanna Seddaiu Antonello Franca Valerio Bondesan Adolfo Rosati Gerardo Marcos Moreno Anastasia Pantera John E. Hermansen Paul J. Burgess 《Agroforestry Systems》2018,92(4):849-862
This paper reports the results of a study conducted in Italy, within the AGFORWARD (2014–2017) project, aimed at promoting innovative agroforestry practices in Europe. Agroforestry offers a means for maintaining food production whilst addressing some of the negative environmental effects of intensive agriculture. This study aims to elicit the positive and negative points of view and perceptions of local stakeholders in Italy in relation to three types of agroforestry systems. The Participatory Research and Network Development was implemented in three workshops conducted in Sardinia, Umbria, and Veneto regions, and applied adopting a common methodological protocol. Qualitative data were obtained using open discussions with stakeholders on key issues, challenges and innovations. Quantitative data were obtained from stakeholders completing questionnaires during the workshops. A statistical analysis was applied to elicit the differences in stakeholders’ positive and negative perceptions in relation to production, management, environment and socio-economy aspects. Although the participants in the study came from different geographical and socioeconomic contexts with varied educational and cultural backgrounds, the different professional groups (farmers, policy-makers and researchers) and the three workshops generally shared similar perceptions of the benefits and constraints. The effects of agroforestry on production and the environment were generally perceived as positive, whilst those related to management were generally negative. The process of bringing the groups together seemed to be an effective means for identifying the key research gaps that need to be addressed in order to promote the uptake and maintenance of agroforestry. 相似文献
19.
Elisabeth S. Simelton Delia C. Catacutan Thu C. Dao Bac V. Dam Thinh D. Le 《Agroforestry Systems》2017,91(1):51-67
Agroforestry is known to have multiple economic and environmental benefits. Despite this, the adoption of agroforestry in Viet Nam is limited both in extent and diversity of components and practices. Our study identified gaps for agroforestry adoption in current policies and policy implementation. National policy and provincial instructions and decisions were reviewed and discussed during ten stakeholders’ consultation workshops. The review and workshops concluded that there were no specific national and few provincial specific policies promoting agroforestry. In addition, the segregation of policies into agriculture and forestry, promoted monoculture practices and discouraged the integration of mixed annual and perennial tree species. Completing the forestland allocation process was considered essential for long-term investment on land and providing collateral for loans. More holistic policies, such as a provincial strategy for agroforestry development that would enable flexible integration of agriculture, forestry and livestock were perceived to be more effective and inclusive to poor and non-poor farmers. Specific cross-cutting budget allocation would be necessary for capacity building, upscaling agroforestry models, procurement of high-quality inputs, and establishing post-harvest processing and marketing investments. 相似文献
20.
Ian K. Dawson Barbara Vinceti John C. Weber Henry Neufeldt Joanne Russell Ard G. Lengkeek Antoine Kalinganire Roeland Kindt Jens-Peter B. Lilles? Jim Roshetko Ramni Jamnadass 《Agroforestry Systems》2011,81(1):67-78
Anthropogenic climate change has significant consequences for the sustainability and productivity of agroforestry ecosystems upon which millions of smallholders in the tropics depend and that provide valuable global services. We here consider the current state of knowledge of the impacts of climate change on tree genetic resources and implications for action in a smallholder setting. Required measures to respond to change include: (1) the facilitated translocation of environmentally-matched germplasm across appropriate geographic scales, (2) the elevation of effective population sizes of tree stands through the promotion of pollinators and other farm management interventions; and (3) the use of a wider range of ??plastic?? species and populations for planting. Key bottlenecks to response that are discussed here include limitations in the international exchange of tree seed and seedlings, and the absence of well-functioning delivery systems to provide smallholders with better-adapted planting material. Greater research on population-level environmental responses in indigenous tree species is important, and more studies of animal pollinators in farm landscapes are required. The development of well-functioning markets for new products that farmers can grow in order to mitigate and adapt to anthropogenic climate change must also consider genetic resource issues, as we describe. 相似文献