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1.
With population growth still at very high rates and large-scale commercial farmers and cattle ranchers owning much of the more fertile valley land, small-scale farmers are concentrated on increasingly marginal, steeply sloping hillsides in Central America. The continuing soil erosion and land degradation in these low-input staple crop production hillside farming systems lead many to be pessimistic about increasing the agricultural incomes of these farmers. However, this study shows that the appropriate combination of improved technologies and agricultural policy or alternative production diversification strategies can improve the incomes of small-scale hillside farmers in southern Honduras by over 50%. The technology components considered are stone walls and ditches combined with living tree barriers to prevent erosion of the hillsides, and a package of improved sorghum seed, seed treatment, and modest doses of nitrogenous fertilizer. A whole-farm mathematical programming framework is used to determine the potential farm-level income effects of the soil-conservation and seed-fertilizer technologies. The main conclusion is that erosion-control devices and yield-increasing crop varieties and fertilizer are an effective technology introduction strategy for the erosion-prone hillside landholdings found in many areas of Central America. If policy actions or diversification strategies for disposal of surplus grain are found which are effective in reducing the risk of low income from cereal price reductions in high-production years, adoption of the improved technologies is shown to be profitable for small-scale farmers. Another benefit not explicitly considered would be to slow the very rapid growth of urban poverty in these countries. Sensitivity analysis results indicated that neither risk aversion nor the increased availability of crop land or initial cash have any substantial effects on the predicted adoption level of the improved technologies, or on their income impacts for these farmers.  相似文献   

2.
Although there is growing demand for animal products in Africa, production is stagnating. Appropriate management of livestock diversity could help reinvigorate production, contribute to food security and improve farmers’ livelihoods, particularly in subsistence‐oriented systems. We assess differences in farmers’ preferences and economic values for pig traits across different production systems and across areas that have been affected and unaffected by classical swine fever (CSF). Not surprisingly, market‐oriented farmers derived higher values from the productive traits such as heavy slaughter weight and large litter size found in exotic pig genotypes. Subsistence‐oriented farmers, particularly in swine fever affected areas, placed high value on tolerance to disease. We found that CSF changed farmers’ preferences for adaptive traits, and less so for productive traits. Therefore, indigenous breeds become more valuable for subsistence farmers and crossbreeds for market‐oriented farmers if CSF is a risk. Our results can have implications for breeding and conservation strategies and for compensation strategies after culling, and will become increasingly relevant if, as predicted, heat waves and disease outbreaks become more frequent in pig production systems in South Africa with climate change.  相似文献   

3.
In Sub-Saharan Africa, fish ponds are often an integral part of farming systems but have suffered from a lack of viability and sustainability. The present study aims to understand the strategies used by fish farmers to overcome economic and environmental constraints. In 2008 and 2009, fish farmers were surveyed in Central and Western Cameroon, and the fish production systems were classified by cluster analysis. Four broad types were identified according to the complexity of household operations. The development of extensive systems (large-scale and low-input) in rural areas of central Cameroon is induced mainly by abundant available land. For semi-intensive systems in both regions (small-scale and high-input in the Western Region, large-scale and high-input in peri-urban areas of the Central Region), horizontal integration is not sufficient to make fish production profitable and sustainable. More intensive fish farms tend towards vertical integration, in which farmers establish close links with input suppliers. Main causes of low productivity of semi-intensive systems (1–2?t/ha/yr) are both lack of knowledge of fish farming principles by farmers and lack of technical improvement by extension agents and researchers which need to consider the local complexity of farming systems to develop and intensify fish production. The adaptation of development strategies to socio-economic and environmental contexts is a necessity to hope for an increase in fish pond aquaculture production in Africa.  相似文献   

4.
Integrating conservation and agricultural production is a major challenge globally. The upper Lachlan catchment of Australia is dominated by livestock grazing, and is threatened because most native woodland vegetation has been cleared. A third of all remaining tree cover occurs as scattered trees in grazing pastures. These scattered trees are dying from old age and are not regenerating due to grazing pressure. Previous work has revealed management strategies that are more likely to maintain tree cover, such as low-input rotational grazing. We asked graziers to photograph significant features on their properties, and used the images as prompts in later interviews. This elicited graziers’ landscape values and other drivers of their management practices related to tree cover. The targets that our 25 case landholders chose to photograph, and the ways they discussed them in later interviews, reflected the focus of past education and incentive programs, suggesting that well-designed policies, educational messages and incentives do seem to reach landholders and result in improved practices. For example, many landholders reported management activities related to the protection of large woodland patches or the maintenance of coarse woody debris. The maintenance of scattered tree cover has not been a focus of policy initiatives in the past. Despite this, the narratives elicited by photos of isolated and scattered trees showed graziers valued them and were aware of and concerned about their decline, yet lacked knowledge about how to protect and regenerate them. Graziers urgently need unambiguous advice and practical assistance to help them adapt their practices to maintain scattered trees in the long term.  相似文献   

5.
Negative carbon emissions options are required to meet long-term climate goals in many countries. One way to incentivise these options is by paying farmers for carbon sequestered by forests through an emissions trading scheme (ETS). New Zealand has a comprehensive ETS, which includes incentives for farmers to plant permanent exotic forests. This research uses an economy-wide model, a forestry model and land use change functions to measure the expected proportion of farmers with trees at harvesting age that will change land use from production to permanent forests in New Zealand from 2014 to 2050. We also estimate the impacts on carbon sequestration, the carbon price, gross emissions, GDP and welfare. When there is forestry land use change, the results indicate that the responsiveness of land owners to the carbon price has a measured impact on carbon sequestration. For example, under the fastest land use change scenario, carbon sequestration reaches 29.93 Mt CO2e by 2050 compared to 23.41 Mt CO2e in the no land use change scenario (a 28% increase). Even under the slowest land use change scenario, carbon sequestration is 25.89 Mt CO2e by 2050 (an 11% increase compared with no land use change). This is because, if foresters decide not to switch to permanent forests in 1 year, carbon prices and ultimately incentives to convert to permanent forests will be higher in future years.  相似文献   

6.
Agroforestry systems have been promoted as sustainable land-use systems for regions where shifting agriculture is the traditional predominant land-use. Although environmentally sustainable, agroforestry systems require investment to establish that may affect their economic sustainability. In the southern Yucatan Peninsula 47 agroforestry plots of two timber and 10 fruit tree species were established with 22 farmers in three communities covering two rainfall zones and five soil types. Some fruit trees had wide adaptability to different soil, rainfall and management conditions, e.g. Manilkara zapota; others were restricted to the best soil, rainfall management conditions, e.g. Persea americana. The Meliaceae timber trees responded little to rainfall and soil, but stem borer attack was markedly lower in less intensively managed systems. Level of system maintenance greatly affected costs, but also opportunities for intercropping and obtaining immediate income. All levels of managements had negative net present value (NPV) for the three-year establishment phase, but so does traditional maize production. Farmers preferred to inter-crop their agroforestry systems, but were often limited by site quality. Determining sustainable agroforestry options for farmers requires multiple decisions related to species adaptability to the site, farmer production objectives and farmer capacity to invest in different management strategies. One production technology did not fit all.  相似文献   

7.
Faidherbia albida is a tree species indigenous to semi-arid regions of Africa that reportedly substantially increases maize (Zea mays) yields in its immediate vicinity. In southern Zambia, F. albida is widely used in indigenous maize farming systems and this has apparently increased over the past two decades. Using a combination of interviews, group meetings, and observations, this study sought to understand why this species seems to have recently been embraced, while other technological innovations apparently have not. We observed a bimodal age distribution of the trees in agricultural fields and posit that the missing cohorts were removed as weeds as a result of evolving notions of what constituted modern farming practices in the emerging maize economy. With subsequent research and social promotion of the beneficial effects of F. albida, farmers now allow the trees to grow in their fields. A holonic analysis points to the important relationship of F. albida to contexts that shaped past and current uses of the tree by farmers on the Tonga Plateau: information, maize, cattle, land tenure, and government policy. Advice promulgated by social promotion activities took root in farmer knowledge contexts because of positive regard for F. albida and timeless injunctions against cutting mature specimens. Furthermore, cultivation of the tree was highly compatible with other important contexts in which farmers operate. However, our research also revealed the potential for adoption of the tree to create new tensions arising from the strong gendering of work and crops in the region.  相似文献   

8.
This paper explores the potential for farmers’ engagement on the issues related to greenhouse gas (GHG) emission mitigation in extensive low-input livestock farming systems. The framework used was based on Participatory Action Research. This involved integrating quantitative evidence on GHG emission impacts at the farm level and qualitative data on the obstacles to the adoption of innovation based on farmers’ perceptions and attitudes to climate change. The study aims at building social capital among 14 farmers in the South West and West Midlands regions in England, and it evaluates the potential for the adoption of emission mitigation strategies. The Rapid Farm Practices Appraisal (RFPA) tool was created to assess farm practices based on their mitigation potential. Practices were assessed twice over 6–9 months. Semi-structured interviews were used to assess barriers and opportunities to farmer engagement and on-farm innovation. Farmers were invited to a focus group meeting to network with other farmers and engage with researchers. All farmers participated in the 2 farm assessments, but only half the farmers adopted changes in farm management. All farmers appreciated the RFPA tool, the clearness of the information provided and the focus of the tool on practices directly. The main obstacles to innovation were limited financial capital, lack of trust in government action and confusion over the effectiveness of farm advice on mitigation. The lack of long-term flexibility of agricultural policies and the source of information greatly influenced the acceptance of advice. Results suggest the potential for the expansion of the RFPA tool to include economic assessment of farm practices and the engagement of a larger pool of farmers and farming systems. The tool could be used to support the GHG Action Plan and future environmental policies, and as an integrated self-assessment tool for farmers under Environmental Stewardship Schemes.  相似文献   

9.
More diverse, perennial cropping systems often have better natural mechanisms for keeping pests at bay. But while scientists emphasise the broad benefits of conservation in terms of effective ecosystem functioning, farmers are more interested in biodiversity for the provision of food or of services such as shade or windbreaks. Because of their limited knowledge of the role of biodiversity in plant protection, farmers sometimes unconsciously disturb natural regulatory mechanisms. Some citrus farmers in Vietnam introduced sapodilla as an intercrop to diversify their source of income, and because this fruit tree requires little care. However, this apparently worthwhile attempt to combine two valuable crops has misfired. The ecological conditions that traditionally sustained natural pest control in citrus have been disturbed, thus trapping farmers in the pesticide treadmill. The weaver ant Oecophylla smaragdina stopped protecting citrus from stinkbugs and leaf-feeding caterpillars after facing competition from the black ant Dolichoderus thoracicus, which favours sapodilla trees as a nesting habitat. To avoid similar scenarios in the future, methods for linking scientific research on ecosystem functions with farmers' own knowledge, experience and priorities are presented. Examples are given of ways in which farmers in perennial cropping systems learn, and how scientists can facilitate this learning process.  相似文献   

10.
Tree species richness, diversity index, standing biomass and biomass carbon stocks were estimated in six villages located under three agro-ecological zones, namely, coastal, hill and plains of Uttara Kannada district, Western Ghats, Peninsular India. The study showed that land use categories other than forest support higher tree species diversity. High basal area, standing biomass and carbon stock in non-forest land categories indicates their potential as carbon sinks and for promotion of species diversity. Inclusion of other non-forest land use categories in afforestation programmes for promotion of multipurpose tree species for conservation of diversity and for enhancing carbon sinks is suggested. There is a need to promote synergy between biodiversity conservation and carbon sequestration under carbon mitigation projects.  相似文献   

11.
To address critical water quality problems, significant public and private sector resources in the U.S. have been directed to promoting and supporting the adoption of conservation practices. Cover crops, in particular, have been a focus of outreach and policy efforts due to their multiple benefits for crop production, carbon sequestration, soil health, and water quality. We hypothesize that Indiana’s state and local agencies have emphasized a systems approach to conservation planning and farm management, which has been successful in reaching a subset of farmers and has established Indiana as a national leader in cover crop adoption. We contend that the systems approach to conservation adoption is not a salient message to farmers who have yet to implement conservation, thus adoption (particularly cover crops) may be stagnant. Early work on systems thinking (ST) in conservation is dominated by qualitative research. Here, we make a first attempt to quantify the relationship between ST and cover crop adoption through producer surveys administered in three Indiana watersheds – St Marys, Big Pine, and Upper White. We found that farmers who adopted cover crops were more likely to be systems thinkers than farmers who had not adopted cover crops. These results have significant implications for conservation planners and educators across the U.S. and internationally who are working to implement additional conservation acreage – a whole farm systems approach to conservation messaging may not be an effective method for farmers who have yet to implement conservation.  相似文献   

12.
Legumes play an important role in sub-Saharan Africa (SSA) farming systems through the provision of food, feed, fuel, income and a range of biophysical benefits, such as soil fertility enhancement and erosion control. However, their full potential is not being realized. The purpose of this study was to assess farmers’ perceptions and knowledge towards legumes and the rationale of farmers for current legume production practices using a survey of 268 farmers in the Democratic Republic of Congo and Kenya. Most of the farmers had some knowledge of legumes and their characteristics. However, they had little knowledge of some key functions, including soil erosion control and soil fertility improvement. Most farmers relied on radio and other farmers for legume-related information. Farmers with relatively large livestock holdings ranked provision of livestock feed as an important legume function. We conclude that farmers put more value on short-term benefits of legumes including food and income than long-term benefits such as natural resource management and thus grain legumes are more readily identified by farmers than forage species. Also, we conclude that farmers require more than just information about legumes to increase uptake, they also require improved market access to procure inputs and sell products to realize other benefits that are associated with growing legumes.  相似文献   

13.
Forest fragmentation is continued to be widespread in the tropics resulting in reduced ecosystem services including carbon storage. However, the effect of forest fragmentation is not considered in the current carbon policy. We investigated the effect of forest fragmentation on tree biomass carbon and soil organic carbon (SOC) storage in a moist tropical forest in Bangladesh. Above and below-ground tree biomass carbon were calculated by using widely accepted allometric equations and SOC was measured by sampling soils up to 10 cm depth and analyzing them in a soil laboratory. Results showed that carbon storage in tree biomass was significantly lower in fragmented forests (16.3 ± 1.37 t C ha−1) than in contiguous forests (31.21 ± 2.75 t C ha−1) (p < 0.001). Likewise, a significantly lower SOC was contained in the soils of fragmented forests (17.26 ± 0.83 t C ha−1) than in contiguous forests (21.62 ± 0.78 t C ha−1) (p < 0.001). Thus a total of 36% less carbon retained in tree biomass and soils in fragmented forests than in contiguous forests. Backward multiple linear regression analysis revealed tree density, tree height, tree DBH, height-diameter ratio (H/D) and tree species richness as influential factors of carbon variation in fragmented forests. All these structural parameters except tree species richness were significantly lower in fragmented forests, were positively associated with carbon storage and explained together 69% of the carbon storage variation. These findings suggest that the altered stand structure and tree allometry likely caused reduced carbon storage in fragmented forests and highlight the importance of landscape scale management intervention in the tropics. Here, we provided with the evidence of strong negative impact of forest fragmentation on carbon storage and argue that this effect should be in consideration which is currently overlooked in existing carbon accounting systems for tropical forests.  相似文献   

14.
One of the main causes of tropical forest loss is conversion to agriculture, which is constantly increasing as a dominant land cover in the tropics. The loss of forests greatly affects biodiversity and ecosystem services. This paper assesses the economic return from increasing tree cover in agricultural landscapes in two tropical locations, West Java, Indonesia and eastern Bangladesh. Agroforestry systems are compared with subsistence seasonal food-crop-based agricultural systems. Data were collected through rapid rural appraisal, field observation, focus groups and semi-structured interviews of farm households. The inclusion of agroforestry tree crops in seasonal agriculture improved the systems’ overall economic performance (net present value), even when it reduced understorey crop production. However, seasonal agriculture has higher income per unit of land area used for crop cultivation compared with the tree establishment and development phase of agroforestry farms. Thus, there is a trade-off between short-term loss of agricultural income and longer-term economic gain from planting trees in farmland. For resource-poor farmers to implement this change, institutional support is needed to improve their knowledge and skills with this unfamiliar form of land management, sufficient capital for the initial investment, and an increase in the security of land tenure.  相似文献   

15.
Transferring carbon from the atmosphere into terrestrial sinks through carbon sequestration practices (so-called ‘carbon farming’) has been proposed as an important component in Australia’s efforts to mitigate greenhouse gas emissions. We use a Best–worst scaling survey to determine which carbon sequestration practices farmers would be most and least likely to adopt, and what factors were most important in any potential adoption decision. The survey was distributed to dryland cropping and mixed crop-livestock farmers in Western Australia. Farmers ranked improved soil quality and reduced soil erosion as the most important potential co-benefits of carbon farming. Factors discouraging farmers from participating in carbon farming contracts were policy and carbon price uncertainty and the uncertain impact of carbon farming practices on productivity and profitability. Farmers had strong preferences for stubble retention and no-till cropping practices as carbon farming strategies. The practices that farmers preferred least were applying biochar and planting trees. Farm and farmer characteristics, including (lack of) awareness of carbon farming policies and opinions about climate change, influence the potential willingness to adopt different carbon farming practices. Given recent policy uncertainty and farmer preferences revealed in this study, it is important to communicate potential co-benefits (rather than opportunities to earn compensation or carbon credits) to increase farmers’ engagement in carbon sequestration activities.  相似文献   

16.
Tropical deforestation and forest degradation are among the top global threats to biodiversity, carbon storage and rural livelihoods, but the social processes underlying these changes remain difficult to observe across large spatial scales and in data-poor contexts such as tropical Africa. We link longitudinal survey data from agricultural households in rural Uganda to high-resolution satellite data on forest cover change, and use this linked dataset to investigate processes at two scales: tree planting and harvesting at the parcel scale, and deforestation and reforestation at the community scale. This multi-scale analysis reveals that tree planting is more common on parcels with secure tenure, by educated heads and in isolated communities. Deforestation is highest in land-rich, agrarian communities with low population density and high baseline forest cover. These results provide explicit evidence that the social drivers of forest change in Uganda vary across scales, indicating a need for additional multi-scale studies.  相似文献   

17.
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   

18.
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   

19.
Slow adoption of conservation farming systems in the Philippine uplands is a major problem. To address this, the landcare approach, based on community landcare groups, is being piloted in several locations. The results of a study to evaluate the impact of the Landcare Program in Barangay Ned in Southern Mindanao are presented. The sustainable rural livelihoods approach was used as a framework for the evaluation. The study focused on two impacts, the adoption of conservation practices and the formation and development of landcare groups, drawing on four data sources—project reports, key informants, a questionnaire survey, and case studies of landcare groups. The Ned Landcare Program has been associated with rapid adoption of conservation farming practices and the rapid formation of landcare groups linked in an association. The main effect of the Program was to enhance human capital through practical, farmer-led training and extension, enabling farmers to incorporate soil conservation and agroforestry technologies in their farming systems, with desirable outcomes for livelihood security and environmental sustainability. The social capital formed, especially through the landcare association, was crucial to these outcomes. Ongoing partnerships with adequately resourced facilitating agencies were required to maintain the Landcare Program in the long term.  相似文献   

20.
This paper presents an empirical case study about farmer management of rice genetic resources in two communities of Nepal, drawing on interdisciplinary, participatory research that involved farmers, rice geneticists and social scientists. The decision‐making process of farm households is modelled and estimated in order to provide information for the design of community‐based conservation programmes. A bivariate model with sample selection examines the simultaneous process of whether farmers decide to plant landraces or modern varieties, and whether the landraces they choose to plant constitute the genetic diversity of interest for future crop improvement. Findings show that the two landrace choices are affected by different social and economic factors, but in certain cases the decision processes are interrelated. Policies to promote the conservation of local rice diversity will need to take both processes into account.  相似文献   

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