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1.
Shadow prices guide farmers' resource allocations, but for subsistence farmers who grow traditional crops they may bear little relationship with market prices. We theoretically derive shadow prices for a subsistence crop with nonmarket value, then estimate shadow prices of maize using data from a nationally representative survey of rural households in Mexico. Shadow prices are significantly higher than market prices for traditional but not improved maize varieties. They are particularly high in the indigenous areas of southern and southeastern Mexico, indicating large  de facto  incentives to maintain traditional varieties there.  相似文献   

2.
During the last three decades in sub‐Saharan Africa, development and research resources have concentrated on the higher‐rainfall and irrigated regions, especially on export crops and the principal food crops grown there. There has been much less concern and investment in semiarid regions without irrigation. Another negative factor has been the lack of public policy concern with the profitability of the basic food crops. With good weather, prices collapse. With bad weather, governments and NGOs dispense food crops as food aid or at subsidized prices. This article documents the importance of the demand side to facilitate diffusion of new technologies for the basic food commodities of semiarid regions—the traditional cereals. With farm programming models aggregated into a sector model, the combination of technological change and demand shifts for sorghum are evaluated in one semiarid region where the traditional cereals are concentrated. It focuses on combining policies to increase the prices farmers receive after introduction of technologies that use higher input levels. It also compares benefits of a strategy that focuses on yield and demand increases for a traditional cereal of the semiarid region, sorghum, with two alternative strategies for the higher‐rainfall zone.  相似文献   

3.
Increasing water scarcity combined with an increasing demand for food and water for irrigation call for a careful revision of water use in agriculture. Currently, less than 60% of all the water used for irrigation is effectively used by crops. Based on the new version of the GTAP‐W model we analyze the effect of potential water savings and the welfare implications of improvements in irrigation efficiency worldwide. The results show that a water policy directed to improve irrigation efficiency led to global and regional water savings, but it is not beneficial for all regions. The final effect on regional welfare will depend on the interaction of several different causes. For instance, higher irrigation efficiency changes opportunity costs and reverses comparative advantages, modifying regional trade patterns and welfare. For water‐stressed regions the effects on welfare are mostly positive. For nonwater scarce regions the results are more mixed and mostly negative. The results show that exports of virtual water are not exclusive of water abundant regions.  相似文献   

4.
Analysing Vietnam's rice export policy and recent export ban in the context of rising food prices, this study combines insights from a regionally‐disaggregated or ‘bottom‐up’ CGE model and a micro‐simulation using household data. Three main conclusions are drawn. First, although there is little impact on GDP, there are substantial distributional impacts across regions and households from different export policies and market conditions. Second, both rural and urban households, including poor households, benefit from free trade, even though domestic rice prices are higher. Finally, under free trade, relatively large gains accrue to rural households, where poverty is most pervasive in Vietnam.  相似文献   

5.
Employing household survey data covering the periods 1992–1993, 1995–1996, and 1999–2000, this article shows for the case of Uganda that a coffee market liberalization followed by a price boom was associated with substantial reductions in poverty, which could even be sustained when prices went down again. Coffee is not planted by the richest farmers and the gains from higher coffee prices accrued to poorer and richer coffee farmers alike. Nor were poorer farmers hurt disproportionately when prices fell. In addition, we find strong spillovers from coffee production to other agriculture, which tends to favor the poor, and to nonagricultural activities. These multiplier effects are concentrated in coffee regions. In an economic environment characterized by a booming agricultural sector, coffee farmers were able to accommodate the negative price shock, in particular through agricultural diversification. General agricultural growth also cushioned possible negative multiplier effects in coffee regions. Overall, the case of coffee in Uganda thus lends support to the view that agricultural trade liberalization is beneficial for the poor.  相似文献   

6.
Farmers in low‐income rural economies often fail to switch to cash crops from staple production despite the positive income effects of commercialization expected by policy makers. The literature suggests that market failures prevent households from cash crop adoption but remains inconclusive regarding farmers' motives and the effects of commercialization. This article contributes to the debate by offering an original approach to the analysis of commercialization outcomes and farmers' decisions. It consists of applying a model with essential heterogeneity and a semiparametric estimation technique to analyzing harvest value returns to cash cropping. Using Malawian data, we show considerable heterogeneity in harvest value returns to cash cropping both within and between groups of farmers choosing different crop portfolios. Importantly, the results imply rational choices based on comparative advantage considerations of farming households: farmers self‐select into the activity where they expect higher gains and adopt cash crops when facing weaker market barriers.  相似文献   

7.
Understanding how producers make decisions to allot acreage among crops and how decisions about land use are affected by changes in prices and their volatility is fundamental for predicting the supply of staple crops and, hence, assessing the global food supply situation. This study makes estimations of monthly (i.e., seasonal) versus annual global acreage response models for the world's principal staple food crops: wheat, corn, soybeans, and rice. Primary emphasis is given to the magnitude and speed of the allocation process. Estimation of intra‐annual acreage elasticity is crucial for expected food supply and for input demand, especially in the light of the recent short‐term volatility in food prices. The econometric results indicate that global crop acreage responds to crop prices and price risks, input costs as well as a time trend. Depending on respective crop, short‐run elasticities are about 0.05 to 0.40; price volatility tends to reduce acreage for some of the crops; comparison of the annual and the monthly acreage response elasticities suggests that acreage adjusts seasonally around the globe to new information and expectations. Given the seasonality of agriculture, time is of an essence for acreage response. The analysis indicates that acreage allocation is more sensitive to prices in the northern hemisphere spring than in winter and the response varies across months.  相似文献   

8.
Using a generalized error correction model, this article measures and compares market integration for export cash crops versus imported food crops for Mali and Nicaragua, and computes transmission elasticities between changes in the goods’ border and domestic prices. Both Mali and Nicaragua obtain the bulk of their export revenue from a particular agricultural commodity—cotton for Mali and coffee for Nicaragua—and both import the same key staple food of rice. To reap the economic gains from this trade specialization, the two countries’ agriculture must be well‐integrated into world markets. The two countries present an important policy contrast that affects their degree of world market integration and price transmission. In Mali, a parastatal enterprise controls its cotton industry, while Nicaragua has less state direction over agriculture. Reflecting this difference, the results show that for both its main export and import commodity, Nicaragua is more integrated into world markets and has higher price transmission than Mali. The results for Nicaragua also show much higher integration and price transmission for its main agricultural export (coffee) than its major import (rice).  相似文献   

9.
This study assesses the potential impact of rising world food prices on the welfare of Ugandan households. While Uganda experienced sharply higher food prices in 2008, as a landlocked, food‐exporting country the causes of those price changes were mainly regional and indirect rather than directly transmitted from global markets. Using trade volumes, food prices, and household survey data we describe how Uganda, unlike some other countries, is partially shielded from direct impacts of global food price movements. Although the majority of Ugandans are net food buyers, the adverse impact at household‐level of rising global prices is moderated by the relatively large quantity and range of staples consumed that come from home production. Moreover, several of these are not widely traded. Some population groups in Uganda are vulnerable to rising food prices, however, primarily those for whom maize is an important staple, including those dependent upon humanitarian relief and the urban poor. Only a relatively small group of Ugandan households will benefit directly and immediately from rising food prices—the significant net sellers of food crops constituting between 12% and 27% of the population. In this assessment we do not estimate the level and extent of wider second round effects from these higher prices.  相似文献   

10.
Determining the value of legumes as soil fertility amendments can be challenging, yet this information is required to guide public policy and to incentivise prescribed land‐management practices such as conservation agriculture. We use a directional input distance function (DIDF) to estimate shadow prices for symbiotic nitrogen and the technical efficiency for mixed maize‐legume production systems in Malawi. The shadow prices reflect the trade‐off between fertiliser nitrogen and symbiotic nitrogen required to achieve a given quantity of output. Our results reveal considerable technical inefficiency in the production system. The estimated shadow prices vary across farms and are, on average, higher than the reference price for commercial nitrogen. The results suggest that it would be beneficial to redesign the current price‐support programs that subsidise chemical fertilisers and indirectly crowd‐out organic soil amendments such as legumes.  相似文献   

11.
Irrigation water pricing: differential impacts on irrigated farms   总被引:10,自引:0,他引:10  
European water policy, as set out in the Water Framework Directive (WFD), requires all EU Member States to implement volumetric water pricing at rates that roughly cover the total costs of providing water services. The objective of this paper is to develop a methodology that, for the different types of farm in an irrigable area, will enable us to analyse the differential impact that a pricing policy for irrigation water would have. For this purpose, Multi-Attribute Utility Theory (MAUT) mathematical programming models were used. The methodology is implemented on a representative area in the Duero Valley in Spain. Our results show the usefulness of differential analysis in evaluating the impact of a water pricing policy. This allows significant differences in the evolution of agricultural incomes to be observed, as well as the recovery of costs by the State, demand for agricultural employment and the consumption of agrochemicals resulting from rising prices of irrigation water in various groups of farmers within a given irrigated area.  相似文献   

12.
Impacts of agricultural and nonagricultural trade liberalization on agriculture are assessed in a multi-commodity, multi-country framework. By modeling simultaneously all goods sectors of the economy, we evaluate the importance of: (a) relative price changes between sectors, and (b) income and exchange-rate adjustments that follow trade liberalization in a world of floating rates. Specifically, we compare two cases using a static world policy simulation (SWOPSIM) model: agricultural multilateral liberalization and complete multilateral liberalization with floating exchange rates for all countries/regions. In both cases agricultural commodity prices tend to increase, an effect which is more pronounced when currency values adjust. The developing countries, in particular Argentina, Brazil and Mexico, have the most significant advances in agricultural and total production when exchange rates vary. Moreover, the gains from international trade are extended to all countries/regions explicitly specified in the model.  相似文献   

13.
This article compares the effects of changing market prices and farm productivity on the welfare of banana‐growing households in the Ntungamo district of Uganda. A heterogeneous‐agent model is applied via a series of mathematical optimization problems, to simulate production and consumption responses of 70 farm households surveyed in 2006. Results show that a given increase in productivity has a greater impact on poverty alleviation than that same increase in market prices. Despite the effects of productivity gains being comparable across different types of household groups, price improvements primarily benefit the incomes of households who are involved in rural producer organizations, who are located closer to markets, and who sell at the market.  相似文献   

14.
We assess the effects of the dramatic rise in agricultural commodity prices during 2007–2008 on income dynamics and poverty among rural households in Bangladesh. A unique panel data set allows us to put the effects of recent events in the context of long‐run trends in income and poverty. We use data from a nationally representative longitudinal survey of rural households in Bangladesh collected in four waves in 1988, 2000, 2004, and 2008. Nargis and Hossain (Nargis, N., Hossain, M., 2006. Income dynamics and pathways out of rural poverty in Bangladesh, 1988–2004. Agric. Econ. 35, 425–435) analysed income dynamics and poverty incidence for the first three waves, finding a declining trend in both the incidence and severity of poverty, aided in particular by human capital development and off‐farm employment opportunities. We update and extend the analysis to include data collected in 2008, at the height of a spike in agricultural prices. We find that the price of a balanced food basket increased by more than 50% during 2000–2008, while household income rose only 15%. As a result the incidence and severity of rural poverty in Bangladesh sunk to pre‐2000 levels during 2004–2008. Thus, the price spikes in 2007–2008 helped push an additional 13 million people into poverty in rural Bangladesh. Moreover, we find that the determinants of poverty have not been time‐invariant. In particular, agricultural production, which had previously been associated with a higher incidence of poverty, served as a hedge against higher food prices during 2004–2008.  相似文献   

15.
We aim to assess the sectoral and poverty impacts of changes in agricultural policy in Colombia. For this, we use an agriculture specialized static computable general equilibrium model, together with a microsimulation model that allows employment to shift between sectors. Results indicate that the sectoral impact from policy changes tends to be small and that it considerably varies across crops. The macro model yields some gains in wages and capital rents, a relatively larger increase in land rents, and limited labor reallocation, together leading to small poverty impacts as calculated through the microsimulation model. The incidence of rural poverty decreases by less than 1% and the same happens to the poverty gap. In addition, poverty reductions are concentrated among households near the middle of the income distribution.  相似文献   

16.
We evaluate the impact of explicitly representing irrigated land and water scarcity in an economy‐wide model with and without a global carbon policy. The analysis develops supply functions of irrigable land from a water resource model for 282 river basins and applies them within a global economy‐wide model. The analysis reveals two key findings. First, explicitly representing irrigated land has a small impact on global food, bioenergy and deforestation outcomes. This is because this modification allows irrigated and rainfed land to expand in different proportions, which counters the effect of rising marginal costs for the expansion of irrigated land. Second, changes in water availability have small impacts on global food prices, bioenergy production, land use change and the overall economy, even with large‐scale (c. 150 exajoules) bioenergy production, due in part to endogenous irrigation and storage responses. However, representing water scarcity and changes in water availability can be important regionally, with relatively arid areas and/or areas with rapidly growing populations fully exhausting our estimated maximum irrigation capacity that allows for improved irrigation efficiency, lining of canals to limit water loss, and expanding storage to fully capture average annual water flows.  相似文献   

17.
The dynamics of biomass growth implies that the yield of irrigated crops depends, in addition to the total amount of water applied, on irrigation scheduling during the growing period. Advanced irrigation technologies relax constraints on irrigation rates and timing, allowing us to better adjust irrigation scheduling to the varying needs of the plants along the growing period. Irrigation production functions, then, should include capital (or expenditures on irrigation equipment) in addition to aggregate water. We derive such functions and study their water-capital substitution properties. Implications for water demand and adoption of irrigation technologies are investigated. A numerical example illustrates these properties.  相似文献   

18.
This article analyzes the effect of production uncertainty on farmland allocation decisions between perennial and annual crops, focusing on a representative farmer's attitude toward risk. A dynamic stochastic optimization model that considers net planting—the difference between new plantings and removals of perennial crops that achieve full production cycle—is used. The effect of uncertainty on the representative farmer's decisions to increase or decrease perennial crops’ acreage, on the optimal path, is examined. Our results reveal that the response of optimal path of net planting to uncertainty related to perennial crop production is highly affected by the farmer's attitude toward risk. A risk‐averse or a low‐risk loving farmer tends to reduce land allocation to perennial crops under uncertainty, while a high‐risk loving farmer will do exactly the opposite. Also, due to disutility of farming, the farmer tends to reduce land allocation to perennial crops when prices are high enough for him to attain a desired income level expectation. One implication of this research is the need for mechanization—in sub‐Saharan countries in particular—that increases per‐acreage yield and output in semisubsistence agriculture.  相似文献   

19.
Rising world prices for fuel and food represent a negative terms‐of‐trade shock for Mozambique. The impacts of these price rises are analyzed using various approaches. Detailed price data show that the world price increases are being transmitted to domestic prices. Short‐run net benefit ratio analysis indicates that urban households and households in the southern region are more vulnerable to food price increases. Rural households, particularly in the North and Center, often benefit from being in a net seller position. Longer‐term analysis using a computable general equilibrium (CGE) model of Mozambique indicates that the fuel price shock dominates rising food prices from both macroeconomic and poverty perspectives. Again, negative impacts are larger in urban areas. The importance of agricultural production response in general and export response in particular is highlighted. Policy analysis reveals difficult trade‐offs between short‐run mitigation and long‐run growth. Improved agricultural productivity has powerful positive impacts, but remains difficult to achieve and may not address the immediate impacts of higher prices.  相似文献   

20.
This article evaluates irrigated agriculture sector response and resultant economic impacts of climate change for a part of the Murray Darling Basin in Australia. A water balance model is used to predict reduced basin inflows for mild, moderate and severe climate change scenarios involving 1, 2 and 4°C warming, and predict 13, 38 and 63% reduced inflows. Impact on irrigated agricultural production and profitability are estimated with a mathematical programming model using a two‐stage approach that simultaneously estimates short and long‐run adjustments. The model accounts for a range of adaptive responses including: deficit irrigation, temporarily following of some areas, permanently reducing the irrigated area and changing the mix of crops. The results suggest that relatively low cost adaptation strategies are available for a moderate reduction in water availability and thus costs of such a reduction are likely to be relatively small. In more severe climate change scenarios greater costs are estimated. Adaptations predicted include a reduction in total area irrigated and investments in efficient irrigation. A shift away from perennial to annual crops is also predicted as the latter can be managed more profitably when water allocations in some years are very low.  相似文献   

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