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1.
In Central Africa, most cacao is still cultivated in low-input agroforests where cacao associated trees are traditionally valued by farmers. These systems are sustainable on the long run, support biodiversity conservation and carbon storage. Yet, little knowledge exists on the contribution of tree community management to explain such results. In Central Cameroon, we investigated cacao agroforest associated tree community contributions to the long-term (i) maintenance of tree species encountering a conservation issue and (ii) carbon storage. We further simulated the simplification of these systems by checking for the effect of tree density decrease on community functional groups or traits. Finally, we linked farmers’ use of associated trees to their functional features and conservation status. Cacao agroforestry systems were able to combine high levels of species richness with long-term conservation abilities and carbon storage. Simplification emphasized consistent shifts of functional traits/groups that will change the way they function and alter the existing balances between different associated tree uses. Since traditional agroforests are now foreseen as providers of timber/non-timber forest products, our study argues that this paradigm change in such low-input systems - if carried improperly - is likely to impair the provision of the services they currently provide as well as their sustainability.  相似文献   

2.
Trees can be considered as investments made by economic agents to prevent depreciation of natural assets such as stocks of top soil and water In agroforestry systems farmers use trees in this manner by deliberately combining them with agricultural crops on the same unit of land. Although advocates of agroforestry have asserted that soil conservation is one of its primary benefits, empirical estimates of these benefits have been lacking due to temporal and spatial complexity of agroforestry systems and the nonmarket aspect of soil capital assets. This study designs and applies a bio-economic framework for valuing the soil conservation benefits of agroforestry. The framework is tested with econometric analysis of data from surveys of households in Eastern Visayas. Philippines, where USAID/Government of Philippines introduced contour hedgerow agroforestry in 1983. By constructing a weighted soil quality index that also incorporates measures of soil fertility, texture and color in addition to erosion, we extend previous economic studies of soil resources. This index is regressed on a variety of farming and site specific bio-physical variables. Next, we use a Cobb-Douglas profit function to directly relate agricultural profits and soil quality. Thus, the value of soil conservation is measured as a quasi-rent differential or the share of producer surplus associated with a change in soil quality. Because this framework assumes the existence of markets, the assumption is tested by analysing the statistical significance of consumption side variables, e.g., number of household members, on production side variables, e.g., profits. Instrumental variables are used to handle the endogeneity of the soil index in the profit equation. Seemingly unrelatedregression (SUR) analysis is used to accommodate correlation of errors across the soil and profit equations. Regression results reveal the importance of agroforestry intensity, private ownership, land fragmentation, and familiarity with soil conservation as positive covariates of soil quality. Analysis of production data indicate the importance of market prices, education, farming experience, farm size, topography, and soil quality as positive covariates of household profits Investments in agroforestry to improve or maintain soil capital can increased annual agricultural profits by US$53 for the typical household, which is 6% of total income. However, there are significant up-front costs. Given that small farmers in tropical uplands are important players in the management of deteriorating soil and forest resources, policy makers may want to consider supporting farmers in the early years of agroforestry adoption.  相似文献   

3.
Integration of trees on upland farms in the Philippines has been slower than expected and desirable from an environmental perspective. Our economic and risk analysis points to current policies as part of the problem. The study compares three domesticated indigenous timber trees (Shorea contorta V., Pterocarpus indicus J., and Vitex parviflora W.) intercropped with maize against a benchmark of the widely used exotic mahogany (Swietenia macrophylla K.). We used a biophysical simulation model (WaNuLCAS 3.1) to represent interaction between trees and crops for a fundamental level of water, nutrient and light capture as the basis for production functions. External conditions affecting systems profitability were accounted for in the Policy Analysis Matrix (PAM). Elements of risk were introduced through Monte Carlo simulation. Study results revealed that from a farmer’s perspective intercropping systems provide similar (within an uncertainty range of + or ? 10%) returns to monocropping scenarios. When net subsidies and taxes are accounted for, social profitability evaluations favour tree intercropping at high tree densities. The net effect of the current bias in price policies towards food production therefore refrains farmers from making decisions to integrate trees on farms; a decision that is actually in the national interest on economic grounds, even without consideration of positive environmental effects.  相似文献   

4.
Environmental and agricultural policy instruments cause changes in land-use which in turn affect habitat quality and availability for a range of species. These policies often have wildlife or biodiversity goals, but in many cases they are ineffective. The low effectiveness and the emergence of unwanted side effects of environmental and agricultural policies are caused by over-simplistic assumptions in the design of policy instruments as well as difficulties with predicting behaviours of policy subjects. When considering wildlife in agricultural landscapes, policy's performance depends both on human (farmers) actions, which the policies aim to affect, and wildlife responses to land-use and management changes imposed by farmers. Thus, in order to design effective agri-environmental policies, detailed ex-ante assessments of both of these aspects are necessary. Due to the restrictive assumptions and technical limitations, traditional agricultural economic and ecological models fall short in terms of predictions of impacts of agri-environmental measures. The feedback situation between policy, human behaviour and ecological systems behaviour can confound these approaches, which do not take systems complexity into account. Therefore, a solution that integrates both feedback interactions and the differing scales at which these interactions take place is needed. For this, we suggest developing integrated policy assessment tools comprising of simulated farmer decision making, on-farm land-use and wildlife responses in the form of spatially explicit, dynamically connected agent-based models. Although complex and necessitating true inter-disciplinarity, these approaches have matured to the point where this endeavour is now feasible.  相似文献   

5.
Even though diversified agroforestry systems can provide sustainable livelihoods and a resilient production of different goods, adoption remains limited in Bolivia. We examine major obstacles to agroforestry adoption and possible incentives proposed by farmers and civil-society organizations, and relate them to governance and international mechanisms that might play a role in agroforestry adoption. Market access for produce from diversified agroforestry remains difficult, as does its processing and transport. Moreover, farmers have difficulties in achieving the quantities and homogenous quality demanded by markets in the major cities. But most importantly, farmers and civil-society organizations saw little government support, although ‘ecological production in harmony with Mother Earth’ is prescribed by law and the constitution. Agroforestry farmers needed support most urgently in the initial phase, when investment costs are high and returns low. They suggested affordable credits, subsidies for diversified farming systems, and insurance against fire. We identified important albeit small steps towards developing markets for agroforestry products, but government support – mostly in the form of diesel subsidies, materials, and infrastructure – mainly benefitted large-scale monocultures and cattle ranching. In response to this, interviewees opted for strengthening farmers’ organizations, for demanding support with the help of civil-society organizations, and for disseminating best practices.  相似文献   

6.
Crop management research is increasingly involving farmers in evaluating new technologies, identifying adoption constraints and opportunities for improving farm performance to produce more sustainable impact. ICRISAT and its partners worked with farmers in Malawi and Zimbabwe during the 1999/2000 and 2000/2001 seasons to evaluate a range of ‘best bet’ soil fertility and water management technologies and evaluate the impact of farmer participatory research. Although there was some variation in methods implemented at different sites, the study found that there is a basis for a comparison of methods. Community entry and participatory approaches that engage farmers in decision making throughout the research-development-diffusion-innovation process have higher setup costs compared to traditional ‘top-down’ approaches. But they improve efficiency, both in technology development and in building farmers' capacity for experimentation and collective learning. This results in the development of more relevant technologies, joint learning among farmers, researchers and extensionists and better impact. To make farmer participatory research projects more sustainable and introduce them on a wide scale, the study recommends that public and NGO investments be targeted to building district and village-level innovation clusters.  相似文献   

7.
Crop diversity is a key principle of sustainable food production systems. Yet, inter and intra specific diversification is declining in many regions of the world. In Northern Malawi, a participatory action research project (Soils Food and Healthy Communities) has conducted agroecological co-learning with farmers for over a decade, providing an opportunity to explore farmer management, crop choice and variety selection practices. Farmers who participate receive seed for 0.10 ha of on-farm testing for one growing season and then decide whether to continue to grow the crop. Cropping system diversity, management practices and traits associated with crops grown and lost were assessed through interviews with 198 farm households (757 fields). We found an average of 1.3 species per field and 4.0 crops per farm. This is almost twice the level of diversity in other reports from Malawi smallholder farms. Farmers cited a wide range of preferred groundnut variety traits, as well as concerns (namely, high labour requirements). Both modern and local maize varieties are being grown and those retained were often associated with early maturity or preferred grain quality traits such as storability. Overall, farmers at this Northern Malawi agroecology education site are growing diverse crop mixtures that include traditional as well as modern varieties of maize and groundnut.  相似文献   

8.
Experiences in smallholder contexts indicate frequent mismatches between technologies introduced and needs of farmers who must make complex decisions in reallocating their limited resources under highly risky ecological and market contexts. This study proposes a cost- and time-effective, easy-to-implement approach to identify farmers’ priorities and critical intervention areas, and presents its application in guiding an agroforestry strategy in Rwanda. It was found that different tree species have distinctive enabling vs. constraining conditions under different agroecological contexts in the perspective of smallholder farmers. Tree species preferred by farmers were not necessarily widely adopted if multitudes of conditions were not enabling. The essential conditions for sustainable adoption include: quality materials/inputs are available; technologies are compatible with existing local farming systems; they are resilient to climate risks/resistant to pests-diseases; management is not complicated; and, there is guaranteed access to markets. The results show that there will not be a silver bullet national strategy to scale up agroforestry. Instead a matrix kind of strategies -to promote enabling conditions and address constraining conditions for priority species in specific agroecologies- will be required. The proposed concept should be further refined for wider agricultural technology transfer debates to break the myths of low uptakes by smallholders.  相似文献   

9.
Frontier development in the Brazilian Amazon has created vast areas of largely deforested landscapes. Conservation efforts in these post‐frontier zones seek to protect the remaining forest fragments and promote sustainable agricultural practices that absorb labor, meet market demand, and generate ecosystem services. Assessments of these efforts often find that rates of sustained uptake are disappointingly low and that impacts are difficult to discern, but this could be due to the short‐time frames of both the efforts themselves and their evaluation. We investigate the impacts of participation in an internationally sponsored farmer association that for 15 years promoted sustainable agricultural practices in the heavily deforested state of Rondônia, Brazil. Using data from a georeferenced four‐period panel survey of farmers in combination with remote sensing data on land use spanning the life of the association, we apply matching methods to estimate the impacts of participation. We find that membership resulted in more diversified production systems, including more land allocated to agroforestry. Members also deforested less of their farms, but this difference is not statistically significant after we control for selection bias in membership.  相似文献   

10.
Innovation in rice (Oryza sativa) productivity improvement is a major goal for rice research. However, many studies have tended to analyse the various factors that affect productivity separately, while farmers invest their scare resources in farm inputs that impact on multiple factors in the real farm. This study assessed the effectiveness of integrated pest management practised during farmer field school (FFS) training in Cambodia on the production efficiencies, yields and profitability of rice farming. In total, 270 FFSs on rice cultivated in the early wet, wet and dry seasons were randomly selected from three provinces in 3 years to analyse the production practices and productivity using six cost-related factors: seed, planting methods, field management, fertilizer use, pesticide application and harvesting. It was found that yields and profits were significantly higher with the technically recommended practices (TRs) than with traditional farmer practices (FPs). However, the reverse was true for production costs due to the overuse of seed and pesticides in FP, neither of which are correlated with yield increase for both FP and TR. Thus, the FFS approach is a knowledge-intensive field management tool that enables the rational use of farm inputs and that is expected to be highly effective for sustainable rice production improvement.  相似文献   

11.
Brazilian small-scale farmers are seeking new types of collaborations and economic opportunities amid a changing world. Market opportunities, however, have incurred demanding environmental, financial and labor requirements, and created trade-offs between expanding cash crops and maintaining livelihood security. We analyze the Tomé-Açu region in the Brazilian Amazon, where different collaborative models between small-scale farmers and other social agents (industries, government, non-governmental organizations) have emerged. Local farmers are engaging in collective actions and pursuing different types of partnerships, which facilitate knowledge exchange and access to market niches, also helping them overcome the infrastructural and logistical deficiencies that have historically limited rural development in the region. In particular, we discuss the diffusion and adoption of agroforestry and oil palm production systems among small-scale farmers. We examine the challenges and opportunities these partnerships and social innovations have created for local farmers, who are part of heterogeneous groups with distinct roles, assets and contexts. The state-led oil palm program posed challenges to small-scale farmers who experienced asymmetrical relationships within their partnership with private companies. On the other hand, the farmer-led agroforestry model opened new opportunities for farmers who had more flexibility in deciding their production arrangements, developing new agroforestry techniques, and pursuing commercialization pathways. Despite their limited power, small-scale farmers have been able to overcome some structural barriers through innovations, entrepreneurship, and renegotiation of oil palm contract farming. Thus, their ability to engage in both farmer-led agroforestry and state-led oil palm programs provides concrete examples of the potential of local governance based on collaborative arrangements to support sustainable farming production systems.  相似文献   

12.
Leguminous agroforestry (AF) species have been investigated and promoted in Malawi as a means to improve soil quality and maize (Zea mays) yields. Our objective was to determine whether AF systems' recommendations that solely consider impacts on average maize yields differ from those that include an analysis of production risk, profitability among different wealth groups and socioeconomic vulnerability. Employing participatory quantitative and qualitative on-farm research techniques, we investigated three AF-based maize/legume relay-cropping practices in southern Malawi. The perennial legumes included Sesbania sesban, Tephrosia vogelii and Cajanus cajan (pigeonpea). We found that AF species recommendations did diverge from those based solely on maximizing maize yields when incorporating risk, profitability and socioeconomic vulnerability as additional variables. For instance, the highest yielding system (the S. sesban/maize relay crop) was never recommended for the most vulnerable farmers based on the vulnerability analysis, and the cropping systems were often more profitable for the least vulnerable farmers than they were for the most vulnerable farmers. Cropping system recommendations based solely on obtaining the highest average maize yields would also have generally overlooked the economic and nutritional importance of pigeonpea, and the difficulty for the most vulnerable farmers to profit from fertilizers, potentially placing these farmers at greater risk.  相似文献   

13.
The overall goal of our article is to better understand which matters for water savings, farmer income and poverty in China's irrigation systems: incentives to managers or participation of farmers. To pursue this goal, the article has three objectives. First, we track the evolution of water management reform, examining the practice of providing incentives to managers, and increasing the participation of farmers. Second, we identify the impact of water management reform on crop water use. Specifically, we want to measure whether or not incentives to managers and farmer participation in water management institutions affect the performance of the irrigation system. Because we also are interested in the potential results of water management reform, the article explores how changes in incentives and farmer participation affect farmer income and poverty. Based on a random sample of 51 villages and 189 farmers in four large irrigation districts in Ningxia and Henan provinces, both in China's Yellow River Basin, our results show that the two major forms of water management reform, water users' associations (WUAs) and contracting, have begun to systematically replace traditional forms of collective management. Our analysis demonstrates, however, that it is not the nominal implementation of the reform that matters, but rather it is the creation of new management institutions that offer water managers monetary incentives that lead to water savings. In contrast to the original design of China's reform policies, participation of farmers has not played a role in saving water. Importantly, given China's concerns about national food production and poverty alleviation, the reductions in water, at least in our sample sites, do not lead to reductions in income and do not increase the incidence of poverty.  相似文献   

14.
In order for farmers to accept improved soil and water management practices, new technologies must be appropriate to the specific site conditions found in the farm setting and be consistent with farmers' objectives and available resources. A whole-farm modeling analysis of this problem is described. Preliminary estimates of the benefits of increased soil moisture conservation for representative low-resource farmers in Mali are presented. If farmers could improve rainfall infiltration from currently low rates of about 40% up to 60%, and use small amounts of chemical fertilizers, disposable income could increase two to four times depending on rainfall. Income could be increased another 50% if the infiltration rate was raised to 80%. Food grain production could increase 60 to 90% with improved moisture conservation and fertilizer use.  相似文献   

15.
Semi-arid West Africa faces challenges to increase sorghum and pearl millet production to meet food needs for a growing human population while increasing soil carbon (C), nutrient levels, and water holding capacity that are documented benefits of conservation agriculture. This review focuses on the wealth of research on cropping systems, tillage, crop residue, nutrient, and weed management as related to conservation agriculture. It also identifies needs for multidisciplinary, integrative research to assist the transition from current production systems to conservation agriculture. Crop residue use as livestock feed, or fuel are major constraints to adoption of conservation agriculture, which could be reduced by wood production in agroforestry systems, alternate energy sources, and increased forage supply. Crop residue and grain yields are related, thus improved crop, soil, water, nutrient, and weed management to increase grain yield would also increase the supply of crop residue with potential for ‘left over’ crop residue being available for soil mulching. Incorporating indigenous shrubs and/or cover crops could also increase crop residue supply. Species diversity can be increased through crop rotation, agroforestry, cover crops, and intercrops. Higher grain and stover yields and increased profit potential for resource-poor farmers in West Africa will be required before wide-scale adoption of conservation agriculture will be possible.  相似文献   

16.
Land and water resource issues typically fall under separate governance systems. For example, agricultural policy regulates land-cover change while water departments regulate water quality. However, land-use changes can directly affect water resources. Water flow regulation is a key service which is affected by changes in land-cover but its dynamics are poorly understood by most policy makers and land management organisations. We simulated and quantified the effects of plant invasions on land-cover, hydrological soil characteristics and catchment responsiveness on flow regulation using a hydrological model. The case study was located in the indigenous fynbos shrublands in South Africa. Fynbos requires fire to regenerate, has moderate biomass, occurs mostly in areas with a potential to erode and is prone to invasion by woody plant species, particularly trees. Invasions can affect flow regulation by changing community structure and function and increasing fuel loads. The greater fuel load increases fire intensity and severity which, in turn, changes the hydrological responses of catchments. Few studies have assessed the effects of invasion on hydrological responses but studies on plantations have recorded significant increases in soil water repellence following fire, resulting in increased overland flow similar to impacts of fires in invaded areas. Simulation of clear-felling of pines and different degrees of water repellency increased both the responsiveness of the catchment to rainfall and extreme rainfall events. The simulated fire effects were consistent with other studies of hydrological responses to fire. Our study indicates that invasions of pines and acacias in the study area could substantially increase the risk of flood damage even from moderate rainfall events, and highlights the importance of maintaining flow regulation capacity. New policy approaches are required which take account of the linkages and interactions between land-use choices, water resources and ecosystem services, and address them when considering governance arrangements.  相似文献   

17.
There is a recognized need for the participation of local communities in designing and implementing agricultural interventions for the sustainable intensification in smallholder systems. This study examines the perspectives of local community leaders towards the widely promoted, but not widely adopted, practice of Conservation Agriculture (CA) in African smallholder systems. Perceptions from 47 community leaders (both from traditional local authorities and farmer organizations) across six African countries are documented regarding how CA matches the wants, needs and capabilities of farmers in their communities. While community leaders generally perceived CA as potentially beneficial, they also indicated that CA is not currently perceived as feasible within their communities and hence has limited relevance. Three key themes were identified that limit both CA use and sustainable intensification more generally: [1] a perceived reluctance of farmers to engage with the community platform as part of a higher input, market-oriented production system; [2] informational constraints due to non-functional exchange mechanisms; and [3] a lack of local adaptation of CA underscored by the persistence of top-down, linear research and extension approaches. Through greater understanding of local perspectives, a clearer picture emerges of the need for greater participatory engagement and local adaptation if sustainable intensification of African smallholder agricultural systems is to be achieved.  相似文献   

18.
Assessing a farm's sustainability: insights from resilience thinking   总被引:1,自引:0,他引:1  
Research on sustainability in agriculture often focuses on reducing the environmental impacts of production systems. However, environmentally friendly production methods may not be sufficient to ensure the long-term economic and social sustainability of a farm. Taking a systems approach to sustainable farming, we turn to resilience thinking with its focus on the interdependence of social and ecological systems. We apply this approach to farming by conceptualizing a farm as being part of a set of systems spanning several spatial scales and including agro-ecological, economic and political-social domains. These subsystems interact and are subjected to their own complex dynamics. Within such a complex adaptive system, farm sustainability can only be achieved through adaptability and change. To be ready for the inevitable periods of turbulent change, a farmer needs to retain diversity and redundancy to ensure adaptability. Resilience is thus more likely to emerge when farmers hone the capacity to transform the farm, when farm production is attuned to the local ecological carrying capacity, and when learning and innovation are targeted outcomes. This article shows how resilience theory applied to farming may provide a more comprehensive route to achieving sustainability and offers rules of thumb as guides to building farm resilience.  相似文献   

19.
Empowering women farmers to participate in agricultural research is a key strategy for sustainable agricultural development. Women empowerment has the potential to improve their roles in agricultural production while enhancing nutrition and food security. Although new agricultural development policies are focusing on improving women engagement in agriculture, there is limited literature on women empowerment in relation to agricultural research. This study used mixed methods to analyse women farmers’ participation in four stages of the agricultural research process – design, testing, dissemination, monitoring and evaluation. Two hundred and thirty individual interviews with women farmers and 16 focus group discussions with men and women farmers were conducted in four Woredas (districts) of Ethiopia. Quantitative data were analysed using binary and multivariate probit models. Qualitative data were analysed using line-by-line coding. The results showed that several empowerment indicator variables significantly (p?≤?.001) influenced women’s participation in different stages of agricultural research. Specifically, input in production decisions, autonomy in plot management, membership to farmer groups, and ability to speak in public enhanced women’s participation in different stages, in addition to access to information and extension services, education and land size. Cultural norms hindered women’s empowerment and engagement in research. To foster sustainable agriculture development, it’s important to integrate holistic and proactive gender perspectives into research strategies to increase women’s participation in farmer research groups, access information and knowledge, have voice and challenge constraining cultural norms and traditions.  相似文献   

20.
Low investments in sustainable land management (SLM) limit agricultural production in the East African Highlands, leading to increased soil erosion, low productivity of land and food insecurity. Recent studies in the region show that different socio-economic factors influence SLM investments by farmers, but knowledge on which of these are most influential and how to foster SLM is often lacking. This research fills this gap for the West Usambara Highlands, and determines key socio-economic factors influencing investments in SLM. Data for this research was collected from 196 randomly selected farm households in the Lushoto district, and Factor Analysis was used to reveal patterns of correlation between SLM investments and different household characteristics. Among the eight socioeconomic factors generated by Factor Analysis, four key factors were found to significantly influence SLM investments in upland (mainly rain-fed) agricultural fields: (1) the farmer’s access to support services; (2) the farmer’s experience with collaborative land management; (3) the household’s income from crop sales; and (4) the farmer’s forward driven attitude. The study concludes that a strategy to foster and scale-up SLM in the West Usambara Highlands should therefore improve the access of farmers to support services (especially micro-credits), trigger collaborative efforts in land management (e.g., farmer-to-farmer training) and promote investments in the rural area to create an enabling environment for SLM. A more active role of the Government, together with public and private sector partners, is therefore crucial.  相似文献   

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