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1.
In addition to experimental data, using information collected from farmers is vital to assess the performance of candidate farming technologies. The latter provides the basis for farmers’ assessments and adoption decisions. Using detailed georeferenced plot and household level data from Ethiopia, this paper estimates the impact of a set of sustainability-enhancing agronomic practices on maize yields and implied net maize income with the aid of multinomial endogenous regime-switching regression that corrects for unobserved heterogeneity. The treatments’ effects on yield ranged from 29.5% for the fertilizer-dominant strategy to 88% in the case of fertilizer, maize-legume diversification, and soil and water conservation combinations. Second, while the impacts of the agronomic packages are significant in almost all states of the world, there were considerable heterogeneity effects conditioned on observed rainfall deviations from the historical average with levels effects of up to 92% and heterogeneity effects of 33–64%. The heterogeneous and rainfall-conditioned impacts point to the role of local biophysical modifiers of the impacts of agricultural practices. Investments in context-appropriate adaptation in agricultural research and extension is suggested.  相似文献   

2.
This article evaluates the impact of the adoption of improved wheat varieties on food security using a recent nationally-representative dataset of over 2000 farm households in Ethiopia. We adopted endogenous switching regression treatment effects complemented with a binary propensity score matching methodology to test robustness and reduced selection bias stemming from both observed and unobserved characteristics. We expand this further with the generalized propensity score (GPS) approach to evaluate the effects of continuous treatment on the response of the outcome variables. We find a consistent result across models indicating that adoption increases food security and farm households that did adopt would also have benefited significantly had they adopted new varieties. This study supports the need for vital investments in agricultural research for major food staples widely consumed by the poor, and efforts to improve access to modern varieties and services. Policies that enhance diffusion and adoption of modern wheat varieties should be central to food security strategies in Ethiopia.  相似文献   

3.
Nationally representative data for Malawi were used to measure the gender gap in adoption of modern maize and to investigate how, if at all, Malawi’s Farm Input Subsidy Program (FISP) has impacted the gap. Regression results show the probability of adopting modern maize was 12% lower for wives in male-headed households, and 11% lower for female household heads, than for male farmers. Receipt of subsidized input coupons had no discernible effect on modern maize adoption for male farmers. Receiving a subsidy for both seed and fertilizer increased the probability of modern maize cultivation by 222% for female household heads, suggesting the FISP has likely reduced the gender gap in adoption of modern maize in Malawi.  相似文献   

4.
This study uses new data from a household survey (n = 179) in Mulanje District, Malawi to examine whether the observed adoption plateaus for modern maize varieties in Malawi partly reflect farmer interest in a diversity of maize seed attributes. Regression results for the study area indicate that specific attributes of different maize varieties are an important influence on their use. The benefits to growing hybrid maize appear to be yield and drought tolerance. Open pollinated varieties are selected by farmers who value early maturity. Local maize varieties are popular among farm households owing to a number of favourable processing and consumption characteristics: storability, poundability, flour-to-grain ratio, and taste. Further research using nationally representative data is needed to assess whether findings for Mulanje District can be generalized to Malawi as a whole. If future studies agree with the results herein then maize breeding research programs in Malawi should consider a diversity of traits beyond grain yield to encompass the range of production, processing, and consumption attributes that are valued by farmers.  相似文献   

5.
Encouraging the widespread adoption and use of new on-farm technologies is an important part of productivity-led strategies to promote agricultural transformation. While many interventions have been designed to promote adoption through extension and education, little is known about how these efforts influence farmer willingness-to-pay (WTP) for new technologies. We use a Becker-DeGroot-Marschak (BDM) mechanism to elicit farmer WTP for two improved seed varieties and a new seed treatment product, Apron Star, under two different lead-farmer extension treatments in Tanzania: (i) a demonstration plot showcasing the technologies within a village; and (ii) a demonstration plot coupled with distribution of trial packs enabling some farmers to test the technologies on their own land. In the BDM, farmers were presented with six products – the two bean varieties: without Apron Star, with Apron Star already applied, and with a sachet of Apron Star for the farmer to treat the seed him/herself. Our results suggest that neither extension treatment significantly affects WTP for these technologies. However, we find that farmers are willing to pay more for seed that is pre-treated with Apron Star than for seed bundled with a sachet of Apron Star for self-treatment.  相似文献   

6.
This paper evaluates the potential impact of adoption of improved legume technologies on rural household welfare measured by consumption expenditure in rural Ethiopia and Tanzania. The study utilizes cross-sectional farm household level data collected in 2008 from a randomly selected sample of 1313 households (700 in Ethiopia and 613 in Tanzania). The causal impact of technology adoption is estimated by utilizing endogenous switching regression. This helps us estimate the true welfare effect of technology adoption by controlling for the role of selection problem on production and adoption decisions. Our analysis reveals that adoption of improved agricultural technologies has a significant positive impact consumption expenditure (in per adult equivalent terms) in rural Ethiopia and Tanzania. This confirms the potential role of technology adoption in improving rural household welfare as higher consumption expenditure from improved technologies translate into lower poverty, higher food security and greater ability to withstand risk. An analysis of the determinants of adoption highlighted inadequate local supply of seed, access to information and perception about the new cultivars as key constraints for technology adoption.  相似文献   

7.
This paper examines how smallholders living in regions where a drought is forecasted adapt their farm practices in response to receiving seasonal forecast information. The article draws on a unique longitudinal dataset in Zambia, which collected information from farm households before and after a significant drought caused by the 2015/2016 El-Niño Southern Oscillation. It finds that farmers residing in areas forecasted to be drought-affected and receiving seasonal forecast information are significantly more likely to integrate drought tolerant crops into their cropping systems compared to similar households not receiving this information. Moreover, the probability that a farmer implements these adaptive farm management strategies in response to seasonal forecast information is found to increase substantially as the number of private grain buyers in the farmers’ village increases. This suggests that climate change adaptation and resilience strategies that integrate the generation and dissemination of weather information with agricultural market development can achieve greater impact on farmers’ adaptive responses than approaches that treat these activities in isolation.  相似文献   

8.
It is widely perceived that African farmers are under-utilizing inorganic fertilizer. However, very little long-term evidence from farmers’ fields, accounting for variations in agro-ecological conditions, has been assembled to back this claim or determine the conditions under which it is true. Using five waves of nationwide household survey data from Kenya covering 13 years, we estimate the relative and absolute profitability of nitrogen application rates on maize fields and compare these profitability conditions to observed nitrogen use patterns over time. In general, we find that farmers are consistently and steadily increasing towards risk-adjusted economically optimal rates of fertilizer application over time and that, in the most agriculturally productive areas, farmers’ application rates on maize sometimes exceed rates that maximize profitability. Fertilizer use rates may nevertheless be profitably raised in these areas, but doing so will require the adoption of complementary inputs and management practices that raise maize response rates to fertilizer application. This motivates a more holistic approach to input intensification strategies in the region.  相似文献   

9.
This study investigates the adoption of three climate-resilient strategies (3CRS), drought/flood-resistant rice varieties, integrated pest management (IPM) practices, and weather advisory; the impact of 3CRS on food security, namely, productivity and profits of the Cambodian paddy farmers. Using endogenous switching regression (ESR) approach and household survey from Cambodian farmers, the study finds a low adoption rate (14%) of 3CRS. The low adoption of 3CRS means missing opportunities for rice farmers. Access to information through training and input suppliers is found to increase the adoption of 3CRS. The adoption of 3CRS increases rice yields and profits by 36% and 45%, respectively. Additionally, if nonadopters adopted 3CRS, rice yields and profits would increase by 55% and 52%, respectively. Findings suggest the development of institutional capacity, implementation, and dissemination of knowledge of climatic changes, and adaptation strategies to increase food security.  相似文献   

10.
Production and price risks that could render input use unprofitable sometimes prevent rural households from benefiting from input technological change. The household’s ability to cope with such risks and hence benefit from input technological change is often positively related to its wealth or stock of productive assets. Empirical evidence, however, suggests a non-linear relationship between wealth and adoption of new agricultural technologies so that within a rural community, households on the lower wealth continuum behave differently from those on the higher level. Using farm level data collected from 300 randomly selected households in three districts of Zambia in 2004/2005 crop season, this paper first stratifies households into poorly- and well-endowed households based on their access to productive assets and estimates separate double-hurdle models for the adoption of improved, high yielding maize (IHYM) varieties for each group. The results show that factors influencing the adoption and use intensity of IHYM varieties differ between the two groups. This draws attention to the need for recommending wealth group-specific interventions to increase the adoption and use intensity of such varieties and their subsequent impacts on food security and general livelihoods of the households. The explicit testing for the possibility that differences in household wealth affect the way in which other variables influence adoption decisions is the paper’s unique contribution to the adoption literature.  相似文献   

11.
We investigate the impact of maize-legume intercropping, soil and water conservation practices (SWC), organic fertilizers, inorganic fertilizers and high yielding maize varieties on maize productivity under weather shocks in Tanzania using panel data. First, we estimate the determinants of adoption by applying a multivariate panel data model capturing their complementarities and/or substitutabilities. Second, after testing for their potential endogeneity, we study the impact of these practices (and combinations of them) on maize productivity controlling for weather shocks. Finally, we disaggregate results by presence/absence of seasonal rainfall and temperature shocks to explore the heterogeneous impact of adoption under weather shocks. We find strong complementarities between agricultural practices both in terms of adoption and yield impacts. Long-run variability in rainfall decreases the adoption of organic fertilizers and increases that of improved seeds. Farmers in areas where the cropping season’s rainfall has been highly variable and temperature has been unexpectedly high have significantly lower maize yields. SWC emerges as one of the most important practices in increasing yields with significant benefits by itself, in combination with other practices, under average weather conditions as well as under rainfall and temperature shocks. Overall, increasing the adoption of SWC appears a promising policy option to buffer food security from increasingly frequent weather shocks in Tanzania.  相似文献   

12.
This study analyzes consumers’ awareness of and attitudes towards yellow maize products in Zimbabwe and suggests intervention strategies that will ensure increased production and consumption of the crop, which is rich in provitamin A to help prevent the incidence of vitamin A deficiency prevalent among vulnerable groups. Data from 360 randomly selected rural and urban households show that yellow maize is known to all but few are aware of its nutritional qualities or consume it. The main source of supply is imported food aid. Rich in oils, carotenoids and fructose, yellow maize easily undergoes chemical changes to produce unacceptable organoleptic properties (or bad taste) if poorly handled during importation. These two factors are responsible for it being perceived inferior to white maize by consumers. Quality assurance during importation can improve consumer confidence but a long-term strategy will be to vigorously promote domestic production of yellow maize varieties rich in high levels of β-carotene that meet the preferences of consumers. Drawing from a probit model regression analysis, nutritional education can potentially promote yellow maize consumption, especially if targeted at low income households. Domestic production and consumption of yellow maize will decrease vitamin A deficiency among vulnerable groups and improve food insecurity through reduced grain prices and increased incomes for farmers. These results draw attention to the need for policy makers in developing countries to review their agricultural policies to ensure that they do not undermine the local production and consumption of nutritionally valuable crops.  相似文献   

13.
This paper investigates the effects of subsidised fertilizer on marketing of maize in Malawi. It uses the nationally representative two-wave Integrated Household Panel Survey (IHPS) data of 2010 and 2013. The results suggest that subsidised fertilizer on average increases farmers’ maize market participation as sellers, total quantity of maize sold, and maize commercialisation. In addition, participation in subsidised fertilizer programme is found to increase the probability of farmers to be net sellers and increases net quantity of maize sold. However, the study finds no evidence of effect on net quantity of maize bought and on household maize self-sufficiency. These results suggest that the farm input subsidy programme has contributed toward an increased level of maize market supply engagement for small farmers and in this sense, the policy has the potential to provide the wider external benefits. Furthermore, the results have implication on the sustainability of the subsidy programme, policy formulation and design of programmes for the agricultural sector and small farmers in developing countries.  相似文献   

14.
Binding resource constraints in many low- and middle-income countries aggravate food insecurity risk in the face of climate change. To help mitigate such risk and increase food security, international development agencies have invested billions of dollars in climate-smart agriculture (CSA) programs over the past decade. However, rigorous evidence on the food security impacts of CSA aid through crop yields remains scant generally, and specifically in sub-Saharan Africa. Most studies have not explicitly linked CSA adoption and yield impacts with CSA aid interventions among smallholder farmers. Here, we respond to this knowledge gap by estimating the impact of a major CSA aid effort (the United States Agency for International Development-funded Wellness and Agriculture for Life’s Advancement (WALA) project) on agricultural yields in Southern Malawi. Based on primary survey data from a sample of 808 households in the project area, we use endogenous switching regression and a control function approach to estimate CSA adoption and impacts on maize yield in 2016, controlling for potential program placement bias, selection bias in CSA adoption, and endogeneity issues. We found a 53% increase in maize yield among CSA adopters in the drought year of 2016. Results demonstrate that policies and funding streams supporting CSA in low-income, dryland contexts such as southern Malawi can have important impacts on food security by boosting crop yields in the face of increasing climate uncertainty and extreme weather shocks.  相似文献   

15.
This paper explores the impacts of hybrid maize adoption on the welfare of farming households in Kenya. We use a four-year panel dataset to estimate the effects of hybrid seed use on four indicators of household welfare, namely, income, assets, inequality and poverty. Results show that use of hybrid seed not only contributes to higher annual income, but also to raising the value of assets, possibly reflecting longer-term welfare effects. Further, we find that use of hybrid seed reduces the depth of poverty, and that the amount planted reduces inequality. As expected, impacts differ between major and minor maize-growing areas of the country. Maize farmers who do not use hybrid seed are clearly disadvantaged. This calls for continued public and private investments in the infrastructure and policy process that supports a competitive, liberalized seed industry and improved access of smallholder farmers to well-adapted, affordable hybrids.  相似文献   

16.
We analyse the impact of improved chickpea adoption on welfare in Ethiopia using three rounds of panel data. First, we estimate the determinants of improved chickpea adoption using a double hurdle model. We apply a control function approach with correlated random effects to control for possible endogeneity resulting from access to improved seed and technology transfer activities. To instrument for these variables we develop novel distance weighted measures of a household’s neighbours’ access to improved seed and technology transfer activities. Second, we estimate the impact of area under improved chickpea cultivation on household income and poverty. We apply a fixed effects instrumental variables approach where we use the predicted area under cultivation from the double hurdle model as an instrument for observed area under cultivation. We find that improved chickpea adoption significantly increases household income while also reducing household poverty. Finally, we disaggregate results by landholding to explore whether the impact of adoption has heterogeneous effects. Adoption favoured all but the largest landholders, for who the new technology did not have a significant impact on income. Overall, increasing access to improved chickpea appears a promising pathway for rural development in Ethiopia’s chickpea growing regions.  相似文献   

17.
Previous studies on the adoption and impacts of improved crop varieties have relied on self-reported adoption status of the surveyed households. However, in the presence of weak variety maintenance and poorly functioning seed certification system, measurement errors in self-reported adoption status can be considerable. This paper investigates how such measurement errors can lead to biased welfare estimates. Using DNA-fingerprinting based varietal identification as a benchmark, we find that misclassification in self-reported adoption status is considerable, with significant false negative and positive response rates. We empirically show that such measurement errors lead to welfare estimates that are biased towards zero and substantially understate the poverty reduction effects of adoption. While the empirical evidence suggests attenuation bias, our theoretical exposition and simulations demonstrate that upward bias and sign reversal effects are also possible. The results point to the need for improved monitoring of the diffusion process of improved varieties through innovative adoption data collection approaches to generate robust evidence for prioritizing and justifying investments in agricultural research and extension.  相似文献   

18.
India imports about half of its domestic consumption needs of edible oils. Groundnuts are a major source of edible oils in India. One of the central problems of groundnut production and processing is huge inefficiencies due to an uncertain production environment owing to rainfed cultivation, the low resource base of smallholder farmers and processors, and the low adoption rates of improved technology. This paper addresses critical issues that impair the groundnut sector’s international competitiveness and efficiency. The paper uses primary data collected from Indian farmers and processors of groundnuts to measure efficiency, and it suggests policies for reducing yield gaps and increasing efficiency. Specific policies suggested from the study are (a) the harnessing of improved varieties with attributes like drought tolerance, high oil content, high productivity for large-scale seed multiplication and distribution by public and private agencies; (b) viable village seed banks and seed networks through cycles of post-rainy season seed multiplication to meet the seed requirements in the rainy season and vice versa; (c) adoption of low-cost technologies to increase profitability and reduce risk; (d) oilseed clusters to facilitate scale and scope economies in processing units; and (e) capital subsidies to accelerate technological upgrading to shed inefficiency in the processing sector. The expected gains in efficiency in the production and processing of oilseeds are expected to result in producer and consumer gains which would justify the proposed incentives for seeds and for technological upgrading in the processing sector.  相似文献   

19.
This paper compares the investment policies and returns for portfolios of stocks and bonds with and without up to three categories of real estate. Both domestic and global settings are examined, with and without the possibility of leverage. The portfolios were generated via the dynamic investment model based on the empirical probability assessment approach applied to past (joint) realizations of returns, both with and without correction for "smoothing" in the real estate data series. Our principal findings are: (1) the gains from adding real estate, on a semi-passive (equal-weighted) basis, to portfolios of either U.S. or global financial assets were relatively modest; in contrast, (2) the gains from adding real estate to the universe of U.S. financial assets under an active strategy were rather large (in some cases highly statistically significant), especially for the very risk-averse strategies; (3) the gains from adding U.S. real estate to a universe of global financial assets under an active strategy were mixed, although generally favorable for the highly risk-averse strategies; (4) correcting for second-moment smoothing in the real estate returns series had a relatively small impact for the more risk-tolerant strategies; and (5) there was some evidence that desmoothing resulted in improved probability estimates.  相似文献   

20.
This paper considers a production-remanufacturing inventory model for a single product, where constant demand is satisfied from the inventory of newly produced and remanufactured items. Although the available models in the literature imply that collected used units (or returns) are disassembled for recovery purposes, these models really do not treat them as such. Contrary, the returns are assumed to be recovered as whole units, perhaps, for simplicity. This assumption may not capture the benefits reaped from product recovery programs. This paper addresses this limitation in the literature and assumes that each unit of a used product is collected and disassembled into components, where these components are sorted into subassemblies, which are fed back into the production-remanufacturing process. The returned subassemblies are remanufactured and reassembled to represent a second source of as-good-as-new units of the end-product. For this multi-component inventory problem, the question that needs to be answered is whether, or not, extreme strategies of either pure remanufacturing or pure production are more economical than a mixed strategy (one that combines both strategies). A mathematical model is developed that accounts for the inventories of subassemblies. The results suggested that not accounting for the disassembled components of a product leads to inappropriate inventory decisions that are not environmentally sound.  相似文献   

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