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1.
This study presents evidence of profound farm‐level transformation in parts of sub‐Saharan Africa, identifies major sources of dynamism in the sector, and proposes an updated typology of farms that reflects the evolving nature of African agriculture. Repeat waves of national survey data are used to examine changes in crop production and marketed output by farm size. Between the first and most recent surveys (generally covering 6 to 10 years), the share of national marketed crop output value accounted for by medium‐scale farms rose in Zambia from 23% to 42%, in Tanzania from 17% to 36%, and in Nigeria from 7% to 18%. The share of land under medium‐scale farms is not rising in densely populated countries such as Kenya, Uganda, and Rwanda, where land scarcity is impeding the pace of medium‐scale farm acquisitions. Medium‐scale farmers are a diverse group, reflecting distinct entry pathways into agriculture, encouraged by the rapid development of land rental, purchase, and long‐term lease markets. The rise of medium‐scale farms is affecting the region in diverse ways that are difficult to generalize. Findings indicate that these farms can be a dynamic driver of agricultural transformation but this does not reduce the importance of maintaining a clear commitment to supporting smallholder farms. Strengthening land tenure security of local rural people to maintain land rights and support productivity investments by smallholder households remains crucial.  相似文献   

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The lack of information as well as some misperceptions about the distinction between the welfare consequences of higher versus more volatile cereal prices has limited the effectiveness of policy interventions during the recent food crises in many developing countries. This article proposes an integrated empirical strategy to investigate and compare the different effects of these two phenomena and tests it using nationally representative household survey data from four sub‐Saharan countries. Results show that the negative impacts of a cereal price increase substantially outweigh the effects of price volatility on household welfare across the entire income distribution. The amplitude and the distribution of those effects depend heavily on specific factors, such as: the weight of food consumption over total expenditure; the budget share devoted to cereals; the substitution effect among food groups; and the relative number of net sellers versus net buyers accessing the market. We also show that volatility mainly harms the poorest quintile of the population.  相似文献   

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This article revisits a conventional wisdom that inorganic fertiliser use across sub‐Saharan Africa is too low. This expectation that more farmers should be using inorganic fertiliser, and at higher rates, implies it is profitable to use rates higher than observed if farmers are rational expected profit maximisers. We obtain consistent estimates of the effects of applied nitrogen on rice production. We find the yield response to applied nitrogen to be low in the main rice growing farming system. Farmer behaviour is not inconsistent with expected profitability which is limited by a low yield response to applied fertiliser, high transportation costs, and low selling prices for rice in rural areas. In particular, we do not find any farmers for whom applied nitrogen is profitable that are not using fertiliser in the study sample for each of our survey years (2010 and 2012).  相似文献   

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This paper briefly presents the results of a total factor productivity (TFP) study of South African commercial agriculture, for 1947‐1997, and illustrates some potential pitfalls in rate of return to research (ROR) calculations. The lag between R&D and TFP is analyzed and found to be only 9 years, with a pronounced negative skew, reflecting the adaptive focus of the South African system. The two‐stage approach gives a massive ROR of 170%. The predetermined lag parameters are then used in modeling the knowledge stock, to refine the estimates of the ROR from short‐ and long‐run dual profit functions. In the short run, with the capital inputs treated as fixed, the ROR is a more reasonable 44%. In the long run, with adjustment of the capital stocks, it rises to 113%, which would reflect the fact that new technology is embodied in the capital items. However, the long‐run model raises a new problem since capital stock adjustment takes 11 years, 2 years longer than the lag between R&D and TFP. If this is assumed to be the correct lag, the ROR falls to 58%, a best estimate. The paper draws attention to the possible sensitivity of rate of return calculations to assumed lag structure, particularly when the lag between changes in R&D and TFP is skewed.  相似文献   

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Following a period of poor performance in the 1990s, India's agricultural growth rate has reaccelerated in the 2000s. Some believe the reacceleration has been a product of intensified investment, which in turn has spurred yield growth. Others suggest it is because India's newly wealthy citizens have demanded greater product diversification. To examine these hypotheses, we use growth accounting techniques in conjunction with more complete agricultural production data than in past studies to construct state, regional, and national output, input, and total factor productivity quantity indexes, which can be decomposed into their underlying sources. Sectoral performance evaluation suggests that, since 1980, output growth has diffused away from the northern “grain belt” and toward high‐value agriculture in traditionally less‐productive regions. Productivity growth, rather than resource use, has accounted for these geographical and intensity shifts. The growth burst has not, as the literature has primarily argued, been uniquely explainable by yield growth or product diversification but by a variety of factors, including area expansion. For example, the contributions of irrigation technologies permitting double‐cropping have until now been largely ignored.  相似文献   

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The study uses a nationally representative dataset of smallholder farmers in Zambia to determine the effect of agricultural productivity on households’ participation in charcoal production. An instrumental variable probit approach is applied to account for the endogeneity of agricultural productivity in household's charcoal participation decision. We find a negative and significant effect of agricultural productivity on household's likelihood of participation in charcoal production. Results also show that higher education, income, asset value, and participation in off-farm employment opportunities reduce the likelihood of participation in charcoal production. Therefore, interventions seeking to reduce charcoal production in rural Zambia could benefit from improving smallholder agricultural productivity, incomes, asset base, and off-farm employment creation. However, interventions need not lose sight of other important macro-level factors.  相似文献   

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This paper departs from the traditional optimisation methods used to evaluate portfolio performance. Rather, the Stochastic Frontier Analysis approach is used to econometrically determine the benchmark real estate portfolio frontier and subsequently assess the gains from diversifying real estate portfolios along regional and sectoral dimensions in the UK. Portfolio specific inefficiency measures are obtained which indicate whether a portfolio is efficiently diversified and therefore places on the benchmark frontier and if not, the degree to which performance can be improved is quantified. Portfolio-specific efficiencies average at 85–91%, indicating scope to further improve performance. Further, diversification be it on a sectoral or regional dimension, contributes to significantly lower variability in portfolio efficiencies.  相似文献   

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Changes are investigated in the Australian agricultural economics profession, 1975–99, using a conventional microeconomics framework of supply and demand for agricultural economists. Aggregate exogenous factors such as changes in the agricultural and tertiary education sectors, and changes in beliefs about the proper role of government, have changed both supply and demand conditions for agricultural economists. The profession has responded by shifting its focus away from narrowly agricultural policy, especially marketing policy, towards areas of market failure such as environmental and natural resource issues.  相似文献   

10.
The agricultural sector is currently confronted with the challenge to reduce greenhouse gas (GHG) emissions, whilst maintaining or increasing production. Energy-saving technologies are often proposed as a partial solution, but the evidence on their ability to reduce GHG emissions remains mixed. Production economics provides methodological tools to analyse the nexus of agricultural production, energy use and GHG emissions. Convexity is predominantly maintained in agricultural production economics, despite various theoretical and empirical reasons to question it. Employing non-convex and convex frontier frameworks, this contribution evaluates energy productivity change (the ratio of aggregate output change to energy use change) and GHG emission intensity change (the ratio of GHG emission change to polluting input change) using Hicks-Moorsteen productivity formulations. We consider GHG emissions as by-products of the production process by using a multi-equation model. Given our empirical specification, non-convex and convex Hicks-Moorsteen indices can coincide under certain circumstances, which leads to a series of theoretical equivalence results. The empirical application focuses on 1,510 observations of Dutch dairy farms for the period of 2010–2019. The results show a positive association between energy productivity change and GHG emission intensity change, which calls into question the potential of on-farm, energy-efficiency-increasing measures to reduce GHG emission intensity.  相似文献   

11.
Consumers are apprehensive about transgenic technologies, so cisgenics, which limit gene transfers to sexually compatible organisms, have been suggested to address consumer concerns. We study consumer preferences for rye bread alternatives based on transgenic or cisgenic rye, grown conventionally or without the use of pesticides, relative to traditionally bred rye, grown with conventional or organic farming methods. Stated preference (SP) data from a choice experiment are combined with revealed preference (RP) data from market purchases from the same respondents. Results show that respondents prefer pesticide‐free production methods, and that while cisgenics is preferred over transgenics, the majority of respondents favour traditional breeding methods. The distribution in preferences suggests that some respondents prefer bread from cisgenic crops produced without pesticides over traditional crops produced using pesticides. Preferences for organic bread are stronger than for pesticide‐free products. From a policy perspective results suggest that excluding cisgenics from mandatory labeling in the EU, or including it in the voluntary non‐GM labelling in the US, would cause welfare losses for consumers.  相似文献   

12.
Aquaculture is one of the fastest growing food‐producing sectors, and its share in global seafood production is rising significantly compared with capture fisheries. This transforms seafood production practices while allowing capital to expand to new marine commodity frontiers. Building on the conceptualization of aquaculture as a new frontier for capture fisheries, the article aims to uncover how commodity frontiers expand within the intensive marine aquaculture sector and shape the transformation of seafood production by focusing on its recent growth in Turkey. It analyses this transformation based on 22 in‐depth interviews with key social actors in Turkey, as well as a review of sector and state reports and the relevant legislations of Turkey and the European Union, and argues that the three‐pronged horizontal, vertical, and taxonomic expansion already observed in industrial capture fisheries has similarly taken place in intensive marine aquaculture through the commodity widening, deepening, and marketing strategies employed by aquaculture firms.  相似文献   

13.
Household surveys, a pivotal component of every country's national statistical system, continue to be criticized and praised in equal manner. While recognizing their limitations, it is clear that certain types of data must continue to be collected through household surveys, preferably in an integrated manner with other data sources. This is particularly true in the agricultural space for which household and farm surveys will be critical both to collect primary data as well as to validate alternative data sources. Recent methodological gains and technological innovations offer a unique opportunity to address many of the shortcomings of agricultural data. In this article, we briefly describe select examples of such methodological and technological changes, drawing from the Living Standards Measurement Study‐Integrated Surveys on Agriculture, a survey program aimed at improving the availability, quality, and relevance of agricultural data in multitopic, multipurpose household surveys.  相似文献   

14.
This paper makes use of a Computable General Equilibrium model to analyze the impact of two agricultural productivity trends on poor households’ food security in Burkina Faso: a negative trend that could arise from many different factors, including land degradation, climate change, and harmful agricultural practices; and a positive trend which may result from enhanced public investment in agriculture, notably in research and development, extension, irrigation, rural roads, rural electrification, and rural education. The results point to a high sensitivity of the poor's consumption to agricultural productivity as well as to stronger impacts on the urban poor than on the rural poor. The current situation is already characterized by severe food insecurity, such that a decline in agricultural productivity is likely to further plunge the urban poor into a deep food crisis. By contrast, positive agricultural productivity trends may help alleviate poverty and food insecurity. Agricultural productivity may indeed affect the poor's food consumption mainly through large changes in agricultural prices and real incomes. Cet article utilise un modèle d’Équilibre Général Calculable pour analyser l'impact des différentes tendances de la productivité agricole sur la sécurité alimentaire des ménages pauvres au Burkina Faso. D'une part, les tendances négatives peuvent résulter de plusieurs facteurs, y compris la dégradation des terres, le changement climatique, et les pratiques agricoles nuisibles. D'autre part, la tendance positive peut résulter de l'investissement public accru dans l'agriculture, notamment dans la recherche et développement, la vulgarisation, l'irrigation, les routes rurales, l′électrification rurale et l′éducation rurale. Les résultats montrent une sensibilité élevée de la consommation des pauvres à la productivité agricole, ainsi que des impacts plus forts sur les populations urbaines pauvres. La situation actuelle est déjà caractérisée par une insécurité alimentaire grave de sorte qu'une baisse de la productivité agricole est susceptible de plonger davantage les pauvres en milieu urbain dans une crise alimentaire profonde. En revanche, la tendance positive sur la productivité agricole peut contribuer à atténuer la pauvreté et l'insécurité alimentaire. La productivité agricole peut en effet affecter la consommation alimentaire des pauvres principalement par le biais de grandes variations des prix agricoles et des revenus réels.  相似文献   

15.
India is considering approving genetically modified (GM) rice, but it fears losing rice exports to sensitive countries with import regulations on GM food, and may wait for China to lead the way. Using a multiregion, computable general equilibrium (CGE) model, we simulate the economic effects of introducing GM rice in India with or without China in the presence of labeling and import approval regulations of GM food in GM sensitive importing countries. We find that the welfare gains with GM rice in India would largely exceed any potential export loss, and that the segregation of non-GM rice could help reduce these minor losses. We also find no significant first mover advantage for India or China on GM rice. The opportunity cost of segregation of non-GM rice is much larger for sensitive importers than for India, which suggests that these importers would have the incentive to pay for the cost of segregation.  相似文献   

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In the analysis of stated preferences studies, it is often assumed that protesting is a discretely measured item only occurring among those who are not willing to pay. However, various studies have recently shown that protest beliefs are as well held by respondents who state a positive willingness to pay (WTP). Using latent class (LC) models, we investigate the extent of heterogeneity with respect to protest beliefs among all respondents of two contingent valuation studies. The advantage of LC models is that classes of individuals are endogenously identified and no selection bias is introduced by ad hoc definitions of protesters. Further we investigate whether it is possible to identify a class of non‐protesters. Finding a group of pure non‐protesters could indicate how strongly stated WTP in the whole sample is affected by protest beliefs. For both samples, we find a class with strong protest beliefs but no pure non‐protest class. Overall, our results suggest that LC models might not be the first choice to determine unbiased WTP measures, but they provide valuable insights into the degree of protesting expressed by different groups and corresponding determinants of group membership.  相似文献   

18.
This paper investigates the dynamic interplay between farm exit and entry of single‐holder farms (SF) in a dualistic farm structure in the Nitra region of the Slovak Republic. Our focus is on economic and noneconomic reasons for farm exit. The impact of varying both the likelihood of succession and the initial farm operator age distributions is studied. An agent‐based simulation model of structural change in agriculture is applied, which brings together farm‐internal and ‐external determinants and creates a set of endogenous adjustment reactions. We show that the stepwise introduction of direct payments of the Common Agricultural Policy in Slovakia has a strong impact on its structural development. In the short‐ to medium‐term, the dualistic farm structure together with a specific age structure of farms still persists as a response to the policy. The phasing‐in of payments persuades SF to stay and potential successors to enter. In the longer run, the initially heterogeneous farm structure becomes increasingly homogeneous toward larger SF. The prevalence of small SF in the medium‐ to long‐term is not necessarily a given. This may lead decision makers to reconsider the role of individual farms in rural development. Dans le présent article, nous avons étudié la relation entre l'entrée en agriculture de fermes à propriétaire unique et leur sortie dans un contexte d'agriculture dualiste dans la région de Nitra, en Slovaquie. Nous nous sommes concentrés sur les raisons économiques et non économiques qui motivent la sortie. Nous avons étudié l'impact liéà la possibilité de relève et à la répartition par âge des agriculteurs. Pour évaluer le changement structurel en agriculture, nous avons utilisé un modèle de simulation multi‐agent qui réunit les facteurs internes et externes et crée un ensemble de réactions d'adaptation endogènes. Nous avons montré que l'introduction progressive des paiements directs accordés dans le cadre de la Politique agricole commune en Slovaquie a des répercussions considérables sur son développement structurel. À court et à moyen termes, l'agriculture dualiste, combinée à la structure de l'âge des exploitations agricoles, demeure une réaction à la politique en place. La mise en place progressive des paiements persuade les exploitations à propriétaire unique de demeurer dans le secteur et encourage les successeurs potentiels à y entrer. À plus long terme, la structure agricole qui était hétérogène au départ devient de plus en plus homogène et compte de plus grandes fermes à propriétaire unique. À court et à moyen termes, la prévalence de petites fermes à propriétaire unique ne va pas nécessairement de soi. Cette situation pourrait amener les décideurs à réexaminer le rôle des exploitations individuelles dans le développement rural.  相似文献   

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