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1.
African countries continue to face deepening food crises that have been accentuated by the global food, energy, and financial crises. This situation is part of a long‐term structural problem: decades of under‐investments in agricultural sector and poor policies of support for smallholder farmers who form the bulk of the farming population. The inability of these farmers to achieve a supply response when commodity prices were high and market access was less of a problem suggests that there are multiple sets of binding constraints that continue to limit the potential of agricultural growth to reduce food security and poverty on the continent. This article reviews some of the historical trends that have hampered the performance of the agriculture sector. In addition, it reviews the impacts of more positive trends that could stimulate agricultural growth in Africa that could change the African agricultural landscape. The article however warns that there are more recent global developments and some continental challenges that could prevent or slow agricultural growth. These include the global financial crisis, public sector investments, inequities in global agricultural development policies, rush for agricultural lands by foreign investors, domestic commercial financing markets, climate change, and emerging carbon markets. The article argues that while opportunities for accelerated growth exists for African agriculture, new sets of policy instruments will be needed to support smallholder farmers to access new agricultural technologies, finance, reduce impacts of climate change, and adopt sustainable land use practices that can allow them to benefit from emerging global carbon markets.  相似文献   

2.
This issue of Agricultural Economics is a special issue containing articles on model performance in assessing the effects of climate change, bioenergy policy, and socioeconomics on agriculture. The contributions present results from a global economic model intercomparison activity undertaken as part of the AgMIP Project ( www.agmip.org ). The origins of the comparison activities can be traced to a project that was organized by the OECD in late 2010 to compare results from three models. The current phase of the research includes 10 models and was designed in part to support of the IPCC fifth assessment report (AR5). The special issue includes seven peer‐reviewed articles that present thematic results from a range of modeling strategies, with partial and general equilibrium modeling as a high level distinction but a myriad of differences within these two model types. A central common element is harmonization on biophysical effects using crop models and socioeconomic effects using drivers from the Shared Socioeconomic Pathways developed as part of the AR5 process. The special issue provides broad insights into how the modeling communities approached the interactions of climate, socioeconomics, bioenergy policy on agricultural outcomes, including land use, prices, consumption, and production.  相似文献   

3.
Changes in agricultural land use have important implications for environmental services. Previous studies of agricultural land‐use futures have been published indicating large uncertainty due to different model assumptions and methodologies. In this article we present a first comprehensive comparison of global agro‐economic models that have harmonized drivers of population, GDP, and biophysical yields. The comparison allows us to ask two research questions: (1) How much cropland will be used under different socioeconomic and climate change scenarios? (2) How can differences in model results be explained? The comparison includes four partial and six general equilibrium models that differ in how they model land supply and amount of potentially available land. We analyze results of two different socioeconomic scenarios and three climate scenarios (one with constant climate). Most models (7 out of 10) project an increase of cropland of 10–25% by 2050 compared to 2005 (under constant climate), but one model projects a decrease. Pasture land expands in some models, which increase the treat on natural vegetation further. Across all models most of the cropland expansion takes place in South America and sub‐Saharan Africa. In general, the strongest differences in model results are related to differences in the costs of land expansion, the endogenous productivity responses, and the assumptions about potential cropland.  相似文献   

4.
Modeling linkages between climate policy and land use: an overview   总被引:1,自引:0,他引:1  
Agriculture and forestry play an important role in emitting and storing greenhouse gases. For an efficient and cost-effective climate policy, it is therefore important to include land use, land-use change, and forestry (LULUCF) explicitly in economy-climate models. This article gives an overview and assessment of existing approaches to include LULUCF into partial and general equilibrium economy-climate models. For each class of models, we describe different examples, their treatment of land, and their potential for and applicability to policy analysis, as well as their shortcomings. We identify data requirements and conceptual problems, and provide suggestions for future research.  相似文献   

5.
The use of laboratory1 experiments in economics, and their later deployment in the field as a tool for exploring how actual decision‐makers respond to information, incentives or institutions has brought a revolution to how we model economic systems, and design policies for them. This new century will bring challenges for the study of agriculture, natural resources and the environment, where it will be necessary to have a better understanding of human behavior, in a world where climate on the one hand, and land, labor and food markets are ever more unstable. This article reviews the intellectual history of a rich dialogue between theory and experiments with a particular focus on its relevance for agricultural, resource and environmental issues. Special attention will be given to the case of common‐pool resources where this dialogue between models, field work and laboratory experiments continues to provide a rich cross‐fertilization for the advance in the understanding of the economic systems that governs these resources. I will close by arguing that agricultural, environmental and resource economists will have to take part of this behavioral revolution by embracing experiments in their teaching, their research and their policy design.  相似文献   

6.
Problems in agriculture and land use are increasingly recognised as complex, uncertain, operating at multiple levels (field to global value chains) and involving social, economic, institutional, and technological change. This has implications for how projects navigate complexity to achieve impact. However, few studies have systematically evaluated how project actors engage with other actors to configure capabilities and resources across multiple levels in agricultural innovation systems (AIS), from the individual to the network, to mobilise and build systemic innovation capacity. An analytical framework conceptualising the nested configuration of capabilities at multiple levels in the AIS is applied to two projects that successfully tackled agricultural and land management problems of differing complexity: (i) improving lamb survival; and (ii) sustainable land management in New Zealand. Findings indicate that innovation capacity constitutes project actors interacting with other AIS actors to configure capabilities and resources at different levels of the AIS in order to leverage positive project path dependencies and break path dependencies that are created by existing and historical capability configurations. Project actors also balance exploiting existing innovation capabilities, as well as using adaptive capability for exploring and creating new capability configurations to respond to emerging circumstances. This implies that projects should have strategic ambidexterity in terms of how they combine exploiting existing and exploring new networks to access, combine, create, or disconnect certain capabilities to address ‘capability voids’ in AIS. This requires support to projects to constantly scrutinise, through reflexive monitoring by dedicated facilitators, specific agriculture and land use policies connected to major sustainable development models (e.g. climate smart agriculture, urban farming, smart farming). The can help assess whether the AIS provides the right mix of capabilities and whether this is adequately supported by innovation policy, to realize transformative policy objectives.  相似文献   

7.
Targeting of agri-environmental measures (AEMs) is a key to increasing the cost-effectiveness of governmental support for biodiversity conservation and the provision of ecosystem services from agriculture. Existing literature, however, often focuses on single measures without considering that policies are usually bundles of different measures addressing multiple non-marketed goods and services. Thus, interaction effects of a set of policies in a given policy mix may influence the cost-effectiveness of single measures. Recently, Swiss agricultural policy was redesigned using the Tinbergen rule as its basis, i.e., a single measure for each policy goal, including additional targeted direct payments. This facilitates testing for interaction effects of multiple targeted AEMs. Here we use a social-ecological, agent-based modelling framework to assess interaction effects of these agricultural policies while accounting for climate change impacts in our analysis. The results from our case study in a mountain region show that ecosystem service provision increases with targeted payments. However, interaction effects of the different targeted policies affect the provision levels of all goods and services. In particular, changes at the extensive margin, i.e., the total amount of land that is under production, largely determine the amount of ecosystem services provided. Thus, climate change driven productivity increases and policies that keep land in production may substantially support the provision of non-marketed goods and services in marginal agricultural production regions with a high potential for land abandonment. Consequently, the effectiveness of targeted policy measures should also consider changes at the extensive margin and be assessed in the context of bundles or portfolios of different policy measures.  相似文献   

8.
The link between trade and the environment has aroused considerable interest both in terms of the impact of trade liberalisation on the environment, and also the impact of environmental policy on production and trade. Of key environmental concern at present is global warming and its association with greenhouse gas emissions. Agriculture is a sector of the economy that both contributes to, and will be affected by, climate change. This paper models the impact of agricultural trade liberalisation on greenhouse gas emissions from agriculture around the world, focusing particularly on the effects on New Zealand, a small economy highly dependent on agricultural trade. A partial equilibrium agricultural multicountry, multicommodity trade model is used for the analysis, extended to include physical production systems and their greenhouse gas emissions. Two simulations are performed: removal of agricultural policies in the EU and in all OECD countries. The results indicate that although producer returns in New Zealand increase, greenhouse gas emissions also increase significantly. EU producers face lower returns but also lower greenhouse gas emissions.  相似文献   

9.
Land is a scarce resource affecting the implementation of many sectoral policies. In Indonesia, the expansion of palm oil plantations has led to non-sustainable land use practices in past years, particularly deforestation. More recently, the government has set ambitious targets for the adoption of biodiesel which will require expansion of oil palm plantations, thus putting further pressure on land. Meanwhile, the need to guarantee food supply, forest conservation and climate change mitigation also imply challenges when it comes to land allocation and use. This paper examines the role that land plays in the implementation of sectoral policies in Indonesia, exploring the availability of land to satisfy the multiple goals defined in national policies. We explore land competition resulting from allocations made in official policy documents starting with biofuel policy. The analysis of policy goals and coherence when it comes to land allocation is made in relation to agriculture, climate and forestry policies. We conclude that adjustments need to be made in the policies to avoid overlappings and misinterpretations when it comes to land allocation. The area made available for meeting each sectoral policy goal when taking into account cross sectoral interactions is: 14.2 Mha for agriculture, 43 Mha for climate mitigation measures, 9.2 Mha for forestry, and 20.9 Mha for biofuels. A more uniform land classification and development of a common reference database will increase transparency on land allocation and use, and help to monitor land use change, ultimately supporting the achievement of multiple national goals.  相似文献   

10.
Assessments of climate change impacts on agricultural markets and land‐use patterns rely on quantification of climate change impacts on the spatial patterns of land productivity. We supply a set of climate impact scenarios on agricultural land productivity derived from two climate models and two biophysical crop growth models to account for some of the uncertainty inherent in climate and impact models. Aggregation in space and time leads to information losses that can determine climate change impacts on agricultural markets and land‐use patterns because often aggregation is across steep gradients from low to high impacts or from increases to decreases. The four climate change impact scenarios supplied here were designed to represent the most significant impacts (high emission scenario only, assumed ineffectiveness of carbon dioxide fertilization on agricultural yields, no adjustments in management) but are consistent with the assumption that changes in agricultural practices are covered in the economic models. Globally, production of individual crops decrease by 10–38% under these climate change scenarios, with large uncertainties in spatial patterns that are determined by both the uncertainty in climate projections and the choice of impact model. This uncertainty in climate impact on crop productivity needs to be considered by economic assessments of climate change.  相似文献   

11.
Agricultural economics is at the nexus of the major policy options surrounding the global bio‐economy. The outputs from agriculture have expanded beyond the traditional food, feed, and fiber to include fuel and other nonfood applications as well as environmental goods due to recent technological developments and changing consumer demands. Numerous policy questions have arisen within the bio‐economy. This article introduces and summarizes several invited panel sessions on issues of special importance in the global bio‐economy: new institutions of dealing with uncertainty and increased volatility related to climate change; structural transformations in agricultural production and food consumption and their effect on development; biofuel policies and development; and determinants of changes in consumer attitudes to new products and technologies.  相似文献   

12.
The pressure on an already stressed water situation in South Africa is predicted to increase significantly under climate change, plans for large industrial expansion, ongoing rapid urbanization, and government programs to provide access to water to millions of previously excluded populations. This article employs a general equilibrium approach to examine the economy‐wide impacts of selected macro and water‐related policy reforms on water use and allocation, rural livelihoods, and economy at large. The analyses reveal that implicit crop‐level water quotas reduce the amount of irrigated land allocated to higher‐value horticultural crops and create higher shadow rents for production of lower‐value water‐intensive field crops, such as sugarcane and fodder. Accordingly, liberalizing local water allocation within irrigation agriculture is found to work in favor of higher‐value crops, and expand agricultural production and exports and farm employment. Allowing for water trade between irrigation and nonagricultural uses fuelled by higher competition for water from urbanization leads to greater water shadow prices for irrigation water with reduced income and employment benefits to rural households and higher gains for nonagricultural households. The analyses show difficult trade‐offs between general economic gains and higher water prices, which place serious questions on subsidizing water supply to irrigated agriculture, i.e., making irrigation subsidies much harder to justify.  相似文献   

13.
Labour-saving technologies are relevant for agricultural development. Yet, as this study shows, they are poorly integrated into agricultural production functions of economy-wide models. We report a computable general equilibrium (CGE) model, which explicitly incorporating field operations (e.g. land preparation, weeding or harvesting) in the context of smallholder agriculture. The field operations approach allows to model technological trade-offs in organic and conventional production systems at various stages of the agricultural production process. Simulating a structural change scenario, we compare the performance of the field operations approach with published benchmark production structures by assessing how they replicate empirically observed changes in land and agrochemical use. This benchmark analysis shows that incorporating field operations replicates the observed empirical changes most accurately and allows for more realistic modelling of labour-saving technologies. We use the field operations model to investigate three policy options to mitigate labour shortages in the agricultural sector of Bhutan. Permitting the employment of Indian workers in agriculture has the highest short-term potential in this respect. We find that subsidising agricultural machinery hiring services and removing import tariffs on agrochemical inputs are found to be less effective. Further options for model developments, such as combining field operations and labour market seasonality, are highlighted.  相似文献   

14.
The paper investigates geo‐physical, agro‐ecological, and socio‐economic determinants of past land use change in two districts of Dak Lak province in the Central Highlands of Vietnam and assesses the influence of rural development policies on land cover change. Landsat satellite images from the years 1975, 1992 and 2000 are interpreted to detect land cover in two time periods. A survey in randomly selected villages provides primary recall data on socio‐economic and policy variables hypothesised to influence land use change. Secondary data on rainfall, soil suitability, and topography was obtained from meteorological stations and from a digital soil map and digital elevation model. All data were spatially referenced using geographic information systems (GIS) software. A reduced‐form, multinomial logit model is used to estimate the influence of hypothesised determinants on land use and the probabilities that a certain pixel has one of five land classes during either of the two periods. Results suggest that the first period from 1975 to 1992 was characterised by land‐intensive agricultural expansion and the conversion of forest into grass and agricultural land. During the second period, since 1992, the rapid, more labour‐ and capital‐intensive growth in the agricultural sector was enabled by the introduction of fertiliser, improved access to rural roads and markets, and expansion of the irrigated area. These policies, combined with the introduction of protected forest areas and policies discouraging shifting cultivation during the second period reduced the pressure on forests while at the same time increasing agricultural productivity and incomes for a growing population. Forest cover during the second period mainly increased due to the regeneration of areas formerly used for shifting cultivation.  相似文献   

15.
Achieving food security at a global scale while protecting the environment, as envisioned in the Sustainable Development Goals, will require a complex process of collaboration and the integration of analyses at multiple scales. Agricultural and land use models are increasingly being used to bridge the global/local divide, particularly as a means to envision future land access, use and management in different agricultural production systems. This special issue contributes to our understanding of global modeling, governance and land use change. Specifically, it provides insights into the question of: how do the ways of knowing and governing affect the politics of environmental protection and agriculture? The papers in this special issue bring reflexive questions of knowledge production, public policy and civic engagement into the epistemic spaces of scientific and technological development, both as a means to improve the way we model and to understand the implications of governing by models.  相似文献   

16.
Existing indicators of agricultural protection and support were developed primarily to gauge the market and welfare effects of government policies. They have shed light on a wider range of impacts through their use in economic models and empirical analysis. The rising scale of support to agriculture globally, and continued reliance on market distorting policy instruments, make this work as important as ever. Deeper investments are nonetheless needed to address heightened concerns about the spill-over impacts of agricultural policies on the performance of food systems, in particular with respect to food security and nutrition, rural livelihoods, resource use and the environment, and global emissions. A first area for development is improved measures of policies to correct agriculture's externalities. A priority here is to develop a carbon tax equivalent of sectoral mitigation efforts. A second area is to provide a clearer delineation of government spending on private versus public goods. This would make a valuable contribution to a ‘repurposing’ agenda that seeks to identify how agricultural budgets can be spent more effectively, as well as the scope for transferring resources to wider social priorities, such as public health and climate action.  相似文献   

17.
We propose a simple heuristic that uses open-access models and government data on agricultural activities to estimate total carbon emissions from agriculture, the gross carbon benefit and the opportunity cost per tonne CO2-e from revegetating to environmental plantings or plantation forestry. We test this across ten areas of mixed land-use that represent diverse Australian agricultural systems along a rainfall transect. The local value of agricultural production was obtained from government statistics and used to estimate the current economic opportunity cost of converting cleared agricultural land to mixed environmental plantings for carbon sequestration. Gross carbon benefit from revegetation was closely related to current agricultural use, as was financial opportunity cost. These were not related simply to site productivity potential or rainfall. The proportion of land cleared for agriculture that would need to be re-vegetated to achieve a localised zero-carbon land-use scenario was calculated by the ratio of current agricultural emissions to gross carbon benefit from revegetation; this ranged from 13% to 66% for groups of agricultural industries across Australian rainfall transects. While the heuristic does not capture the detail of models built specifically for local research questions it does provide a different lens on the questions policy makers and land managers may ask about the costs and benefits of revegetating agricultural land, and provides open-access methods to guide them.  相似文献   

18.
Agricultural research on climate change generally follows two themes: (i) impact and adaptation or (ii) mitigation and emissions. Despite both being simultaneously relevant to future agricultural systems, the two are usually studied separately. By contrast, this study jointly compares the potential impacts of climate change and the effects of mitigation policy on farming systems in the central region of Western Australia’s grainbelt, using the results of several biophysical models integrated into a whole‐farm bioeconomic model. In particular, we focus on the potential for interactions between climate impacts and mitigation activities. Results suggest that, in the study area, farm profitability is much more sensitive to changes in climate than to a mitigation policy involving a carbon price on agricultural emissions. Climate change reduces the profitability of agricultural production and, as a result, reduces the opportunity cost of reforesting land for carbon sequestration. Nonetheless, the financial attractiveness of reforestation does not necessarily improve because climate change also reduces tree growth and, therefore, the income from sequestration. Consequently, at least for the study area, climate change has the potential to reduce the amount of abatement obtainable from sequestration – a result potentially relevant to the debate about the desirability of sequestration as a mitigation option.  相似文献   

19.
The purpose of this study is to evaluate the effects of changes in the external trade environment and domestic economic policies on the agricultural development of Malaysia. The scope of this research also includes providing further insights into the strengths and weaknesses of the computable general equilibrium (CGE) methodology for agricultural policy analysis. The first analysis focuses on the export agriculture sector which encompasses Malaysia's two primary agricultural commodities, rubber and palm oil. Heavily dependent on exports of rubber in the 1950s and 1960s, Malaysia has since built a more diversified economy with strong emphasis on manufacturing. Export agriculture, however, is still an important component of the national economy. The second objective examines the influence of domestic policy on agricultural development. The simulation results demonstrate the growing resiliency of the Malaysian economy to external shocks. Also, they point to the domestic economy's ability to buffer internal Policy-induced distortions.  相似文献   

20.
The sustainability of smallholder agriculture in the drylands of West Africa is a topic of long-lasting concern. This paper is focused on the scientific assessment of nutrient (mis)management affecting the long-term productivity of cropland. “Nutrient mining” is seen as a major mechanism for land degradation in the region. Two models will be the focus: that tied to the rangeland-to-cropland metric and the nutrient balance model. These tools of assessment follow a long history of environmental assessment and modeling that purposefully abstracts from the heterogeneity of the same farming practices that modeling efforts seek to assess. Abstraction is always part of modeling but the form of abstraction described here ignores any detailed understanding of farming practices and in so doing, demands very little information about farming practices. In this way, models serve as both the symptom and cause of continued ignorance of farming practices by most agronomists and soil scientists working in the region. The variables used in these models will be described and how these same variables are strongly influenced by the variation of farmers’ practices will be discussed. In addition, it will be shown that needless model abstraction results in research outcomes that provide very little insights to guide land policy formulation and agricultural extension. In short, these models point to the ultimate resource limits of the regional agricultural system but provide few insights of what could be changed to reduce rates of land degradation. The paper concludes by presenting alternative approaches that through their engagement with the diverse positionalities of farmers, provides insights useful for the development of effective land policies.  相似文献   

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