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1.
Brazil is trying to identify ways to ally economic growth with climate change mitigation. Productivity gains in livestock have been pointed out as a promising alternative to achieve that goal. Thus, this paper analyses the economic impacts of a policy of productivity gains in the Brazilian livestock. Besides, we evaluate if the policy may conciliate agricultural growth and deforestation control, bearing in mind the reduction of greenhouse gas (GHG) emissions from land-use changes. The analysis was carried out through a computable general equilibrium (CGE) model, tailored to represent land-use changes, GHG emissions and removals. Besides, it made progress modeling the heterogeneity of climate, soils, and emissions in inter-regional models with many regions. The results show that productivity gains can effectively “save” land and thus avoid deforestation, especially in the Amazon and Cerrado (savannah) biomes. The policy also may boost the economic growth, spreading it to other regions of Brazil, like Centre-West and North, and increasing income and consumption in those places. However, as a climate policy, focused on the reduction of GHG emissions, the results may be counterproductive. The net amount issued may increase, as a result of the positive stimulus of the policy on the economy, and GHG emissions are directly related to the economic growth.  相似文献   

2.
Relative agricultural productivity shocks emerging from climate change will alter regional cropland use. Land allocations are sensitive to crop profits that in turn depend on yield effects induced by changes in climate and technology. We develop and apply an integrated framework to assess the impact of climate change on agricultural productivity and land use for the U.S. Northern Great Plains. Crop-specific yield–weather models reveal crop comparative advantage due to differential yield impacts of weather across the region's major crops, that is, alfalfa, wheat, soybeans, and maize. We define crop profits as a function of the weather-driven yields, which are then used to model land use allocation decisions. This ultimately allows us to simulate the impact of climate change under the RCP4.5 emissions scenario on land allocated to the region's major crops as well as to grass/pasture. Upon removing the trends effects in yields, climate change is projected to lower yields by 33–64% over 2031–2055 relative to 1981–2005, with soybean being the least and alfalfa the most affected crops. Yield projections applied to the land use model at present-day input costs and output prices reveals that Dakotas’ grass acreage will increase by up to 23%, displacing croplands. Wheat acreage is expected to increase by up to 54% in select southeastern counties of North Dakota and South Dakota, where maize/soy acreage had increased by up to 58% during 1995–2016.  相似文献   

3.
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   

4.
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   

5.
Brazil has become an agricultural powerhouse, producing roughly 30 % of the world’s soy and 15 % of its beef by 2013 – yet historically much of that growth has come at the expense of its native ecosystems. Since 1985, pastures and croplands have replaced nearly 65 Mha of forests and savannas in the legal Amazon. A growing body of work suggests that this paradigm of horizontal expansion of agriculture over ecosystems is outdated and brings negative social and environmental outcomes. Here we propose four strategies that can reduce deforestation, while increasing production and social wellbeing. First, eliminate land grabbing and land speculation through designation of public forests. This would clarify land tenure and limit the pool of land available for uncontrolled expansion of agriculture and ranching. Second, reduce deforestation on private properties by implementing existing mechanisms in Brazil’s Forest Code to facilitate payments for environmental services, with support from market initiatives for sustainable sourcing of agricultural products. Third, incentivize increased productivity on medium and large properties through targeted investments. By stimulating adoption of proven technologies for sustainable intensification, this would help meet Brazil’s production targets and growing international demand for agricultural products, without expanding into new production areas. Finally, foster economic, environmental and social improvements through technical assistance to small farmers. Small farmers occupy a large swath of the Amazon and often lack access to technical assistance, production technology, and markets. Providing quality technical assistance to small farmers could help them better align production practices with local opportunities; increase household income and improve livelihoods; and reduce deforestation pressure. By implementing these four strategies in a coordinated effort between public and private agents, Brazil can show the world how to reduce deforestation while increasing agricultural output, reestablishing its leadership in managing natural resources and mitigating climate change.  相似文献   

6.
Asian developing countries have had varying experiences in trade and agricultural development in the 1980s, attributable in part to their differing stages of economic development and structural characteristics. Other important influences relate to the external economic environment and the policy choices made by their governments not only during the period but also in the preceding decade. The achievements of Asian developing countries under the adverse external conditions of the 1980s are discussed in terms of their macrocconomic and agricultural growth, the commodity structure of agricultural growth, their food production and trade, the expansion and diversification of their agricultural exports, and the policy and nonpolicy factors affecting them. Special attention is given to the role of policy reforms implemented in China and the South Asian countries, following similar policy developments in Northeast and Southeast Asia in the 1960s and 1970s, toward greater openness in their trade regime and increased private-sector participation in the economy. These reforms have contributed to the observed acceleration in gup , agricultural, and export growth in the 1980s. However, macroeconomic imbalances have emerged that threaten the sustainability of economic liberalization in those countries. The major challenges for the 1990s also differ among the Asian developing countries. In the industrially advanced Northeast economies of Taiwan and South Korea, the primary need is to ease the transition of the remaining rural population as farm incomes continue to fall and workers move to industrial and service activities. This challenge has to be addressed in the context of growing external pressure to further open their domestic market for agricultural imports. Among the Southeast and South Asian countries, there is a need to reduce the existing policy biases against agriculture, particularly against export crop production. Moreover, China and the South Asian countries face the additional challenges of continuing to deregulate their trade regime and internal markets, and of promoting macroeconomic stability. Despite the external trend recently toward regionalism, Asian developing countries generally seem committed to an open trading system, on which in fact their past impressive economic performance has been predicated. An important challenge for them in the 1990s is to play an active role in arresting and reversing any protectionist tendencies arising from the formation of regional trading blocs and to support multilateral initiatives such as the Uruguay Round that promote global trade liberalization.  相似文献   

7.
Estimates show that, in recent years, deforestation and forest degradation accounted for about 17% of global greenhouse gas emissions. The implementation of REDD (Reducing Emissions from Deforestation and Forest Degradation in Developing Countries) is suggested to provide substantial emission reductions at low costs, although cost estimates show large uncertainty. Cost estimates can differ, as they depend on the approach chosen, for example: giving an economic stimulus to entire countries, taking landowners as actors in a REDD framework, or starting from protecting carbon-rich areas. This last approach was chosen for this analysis. Proper calculation of the economic cost requires an integrated modelling approach involving biophysical impact calculations and their associated economic effects. To date, only a few global modelling studies have applied such an approach. In modelling REDD measures, the actual implementation of REDD can take many forms, with implications for the results. This study assumes that non-Annex I countries will protect carbon-rich areas against deforestation, and therefore will refrain from using these areas as agricultural land. The opportunity costs of reducing deforestation within the framework of REDD were assessed using an integrated economic and land-use modelling approach comprising the global economic LEITAP model and the biophysical IMAGE model. One of the main methodological challenges is the representation of land use and the possibility to convert woodlands land into agricultural land. We endogenised the availability of agricultural land by introducing a flexible land supply curve, and represented the implementation of REDD policies as a reduction in the maximum amount of unmanaged land that potentially would be available for conversion to agriculture, in various regions in the world. In a series of model experiments, carbon-rich areas in non-Annex I countries were protected from deforestation. In each consecutive scenario the protected area was increased, starting off with the most carbon rich lands, worldwide systematically working down to areas with less carbon storage. The associated opportunity costs, expressed in terms of GDP reduction, were calculated with the economic LEITAP model. The resulting net reduction in carbon dioxide emissions from land-use change was calculated with the IMAGE model. From the sequence of experiments, marginal cost curves were constructed, relating carbon dioxide emission reductions to the opportunity costs. The results showed that globally a maximum of around 2.5 Gt carbon dioxide emissions could be avoided, annually. However, regional differences in opportunity costs are large and were found to range from about 0 to 3.2 USD per tonne carbon dioxide in Africa, 2 to 9 USD in South America and Central America, and 20 to 60 USD in Southeast Asia. These results are comparable to other studies that have calculated these costs, in terms of both opportunity costs and the regional distribution of emissions reduction.  相似文献   

8.
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   

9.
Over the past centuries, land systems in Italy experienced fundamental shifts, owing to the availability of new energy forms, population surges, and technological progress. The 20th century was characterized by massive productivity increases, accompanied by gradual land abandonment and the return of forest land. We here analyze 120 years of land system change in Italy, applying the human appropriation of net primary production (HANPP) framework, a metric for socio-economic pressures on terrestrial ecosystems. HANPP allows integrating ecological with societal perspectives, by systematically quantifying (a) biomass harvest and (b) the difference between potential productivity of ecosystems and current productivity induced by land use processes, such as land conversion, or land degradation. Besides assessing national trends we calculated HANPP separately for the Italian North and South between 1934 and 2007, in order to scrutinize if high regional discrepancies in terms of natural and socio-economic preconditions translate into diverging land system trajectories. Our results show that national HANPP has been declining from 78% of natural productivity before WWII to 56% in 2007, indicating a declining land -use induced pressure on biomass flows over time. Simultaneously, biomass harvest increased by around 26% due to agricultural intensification, despite shrinking croplands. Although we found a significant difference between the Northern and Southern region in the absolute levels of several land use indicators related to biomass appropriation, the overarching trends of land system change were remarkably similar in both regions. This suggests that underlying drivers of land system change, such as policies aimed at land-use intensification and structural change were equally dominating land system trajectories in the North and South of Italy, not withstanding their socio-ecological divergences.  相似文献   

10.
Land‐use change in developing countries is of great interest to policy‐makers and researchers with diverse interests. Concerns about consequences of deforestation for global climate change and biodiversity have received the most publicity, but loss of wetlands, declining land productivity and watershed management are also problems facing developing countries. Analyses of these problems are especially constrained by lack of data. This article reviews modelling approaches for data‐constrained environments that involve discrete choice methods including neural nets and dynamic programming, and research results that link individual household survey data with satellite images using geographic positioning systems.  相似文献   

11.
This paper examines partial agricultural land and labour productivity in 1975 and 1980, for different world regions. The results suggest that land and labour productivity are higher in developed countries relative to developing countries. However, agricultural labour productivity differences are more marked than those for agricultural land productivity. The productivity values for 1975 and 1980 indicate a widening of productivity differences, more so in the case of agricultural labour than land. The paper also proposes an alternative approach to estimating agricultural land and labour productivity. This approach, which regresses agricultural labour productivity on a given level of agricultural land productivity, suggests a narrowing of agricultural land productivity differences, relative to the initial approach, across Africa, Asia and Europe during the 1975-1980 period. A brief discussion of the agricultural development policy implications of the results concludes the paper.  相似文献   

12.
Landholdings and land parcels in South Asia are undergoing fragmentation, thereby accelerating the pace of their degradation and constraining agricultural development. Based on experiences gained in the region and elsewhere, this paper finds the fragmentation of small landholdings and tiny land parcels detrimental to land conservation and economic gain, thereby discouraging farmers from adoption of agricultural innovations. Primarily induced by the dependency of the major proportion of ever growing population on agriculture, the process of land fragmentation has been reinforced by the law of inheritance of paternal property, lack of progressive tax on inherited land, heterogeneous land quality and an underdeveloped land market. South Asian countries have had adopted policies and legal measures for facilitating land consolidation. However, desirable results were not achieved, as such interventions could not address structural causes of the problem. Broad policy and legal measures have been outlined for facilitating land consolidation in a sustainable way.  相似文献   

13.
This paper examines evidence of the effects of economic liberalization and globalization on rural resource degradation in developing countries. The principal resource effects of concern are processes of land use change leading to forestland conversion, degradation and deforestation. The main trends in globalization of interest are trade liberalization and economy-wide reforms in developing countries that have 'opened up' the agroindustrial sectors, thus increasing their export-orientation. Such reforms have clearly spurred agroindustrialization, rural development and economic growth, but there is also concern that there may be direct and indirect impacts on rural resource degradation. The direct impacts may occur as increased agricultural activity leads to conversion of forests and increased land degradation from 'unsustainable' production methods. However, there may also be indirect effects if agroindustrial development displaces landless, near-landless and rural poor generally, who then migrate to marginal agricultural lands and forest frontier regions. This paper explores these direct and indirect effects of globalization and agroindustrialization on rural resource degradation both generally, plus through examining case study evidence. The paper focuses in particular on the examples of structural adjustment, trade liberalization and agricultural development in Ghana, and maize sector liberalization in Mexico under North American Free Trade Agreement (NAFTA).  相似文献   

14.
The Lore Lindu region in Indonesia—as in many forest frontier areas in Southeast Asia—has experienced rapid deforestation due to agricultural expansion in the uplands, at the forest margins. This has resulted in aggravated problems of erosion and water availability, threatening agricultural productivity growth. At the same time, technical progress is promoting agricultural intensification in the lowlands. In this article, we examine how improved technologies for paddy rice cultivation in the lowlands have affected agricultural expansion and deforestation in the uplands. The question of a “forest‐saving” or “forest‐clearing” effect related to technical innovation is important from a sustainable development perspective and remains a controversial issue in the literature. We address this question for the Lore Lindu region with an empirical model in which expansion in the lowlands and the uplands is estimated simultaneously. We use data from an extensive village survey conducted in the region, combined with GIS data. To guide the empirical analysis, we develop a theoretical framework based on a Chayanov‐type agricultural household model. The model analyzes farmers' land allocation decisions, taking into account the lowland–upland dichotomy in the agricultural sector. The empirical findings, corroborated by the analytically derived results, show how technical progress for lowland production affects land use at the forest margins and how these effects depend on the factor‐intensity of the technology. The findings imply specific rural development policies for sustainable agricultural intensification in forest frontier areas.  相似文献   

15.
In this paper we analyze the indirect land use change (ILUC) effects of ethanol production expansion in Brazil through the use of an inter-regional, bottom-up, dynamic general equilibrium model calibrated with the 2005 Brazilian I-O table. A new methodology to deal with ILUC effects is developed, using a transition matrix of land uses calibrated with Agricultural Censuses data. Agriculture and land use are modeled separately in each of 15 Brazilian regions with different agricultural mix. This regional detail captures a good deal of the differences in soil, climate and history that cause particular land to be used for particular purposes.Brazilian land area data distinguish three broad types of agricultural land use, Crop, Pasture, and Plantation Forestry. Between one year and the next the model allows land to move between those categories, or for unused land to convert to one of these three, driven initially by the transition matrix, changing land supply for agriculture between years. The transition matrix shows Markov probabilities that a particular hectare of land used in one year for some use would be in another use next period. These probabilities are modified endogenously in the model according to the average unit rentals of each land type in each region.We ask whether biofuel expansion is consistent with new laws, limiting forest clearing in Brazil. A simulation with ethanol expansion scenario is performed for year 2020, in which land supply is allowed to increase only in states located on the agricultural frontier. Results suggest that each new hectare of sugar cane requires only 0.14 ha of new land, with another 0.47 ha converted from pasture use. Hence policies limiting deforestation are unlikely to prevent greater ethanol production. Finally, regional differences in sugarcane productivity are found to be important elements in ILUC effects of sugar cane expansion.  相似文献   

16.
Fed by demand for beef within Brazil and in global markets, the Brazilian herd grew from 147 million head of cattle in 1990 to ≈200 million in 2007. Eighty-three percent of this expansion occurred in the Amazon and this trend is expected to continue as the industry bounces back from a recent agricultural downturn. Intensification of the cattle industry has been suggested as one way to reduce pressure on forest margins and spare land for soybean or sugarcane production, and is the cornerstone of Brazil's plan for mitigation of greenhouse gas emissions. To this end, federal credit programs and research and development activities in Brazil are aligning to support intensification goals, but there is no guarantee that this push for intensification will decrease the demand for land at the forest margin and as result curb CO2 emissions from deforestation. In this paper we use a spatially explicit rent model which incorporates the local effects of biophysical characteristics, infrastructure, land prices, and distance to markets and slaughterhouses to calculate 30-year Net Present Values (NPVs) of extensive cattle ranching across the Brazilian Amazon. We use the model to ask where extensive ranching is profitable and how land acquisition affects profitability. We estimate that between 17% and 80% of land in the Amazon would have moderate to high NPVs when ranched extensively if it were settled, i.e. if the rancher does not buy the land but acquires it through land grabbing. In addition, we estimate that between 9% and 13% of land in the Amazon is vulnerable to speculation (i.e. areas with positive NPVs only if land is settled and not purchased), which suggests that land speculation is an important driver of extensive ranching profitability, and may continue to be in the future. These results suggest that pro-intensification policies such as credit provision for improved pasture management and investment in more intensive production systems must be accompanied by implementation and enforcement of policies that alter the incentives to clear forest for pasture, discourage land speculation, and increase accountability for land management practices if intensification of the cattle sector is to deter new deforestation and displace production from low-yield, extensive cattle production systems in frontier regions of the Brazilian Amazon.  相似文献   

17.
Integrated Assessment studies have shown that meeting ambitious greenhouse gas mitigation targets will require substantial amounts of bioenergy as part of the future energy mix. In the course of the Agricultural Model Intercomparison and Improvement Project (AgMIP), five global agro‐economic models were used to analyze a future scenario with global demand for ligno‐cellulosic bioenergy rising to about 100 ExaJoule in 2050. From this exercise a tentative conclusion can be drawn that ambitious climate change mitigation need not drive up global food prices much, if the extra land required for bioenergy production is accessible or if the feedstock, for example, from forests, does not directly compete for agricultural land. Agricultural price effects across models by the year 2050 from high bioenergy demand in an ambitious mitigation scenario appear to be much smaller (+5% average across models) than from direct climate impacts on crop yields in a high‐emission scenario (+25% average across models). However, potential future scarcities of water and nutrients, policy‐induced restrictions on agricultural land expansion, as well as potential welfare losses have not been specifically looked at in this exercise.  相似文献   

18.
Reducing carbon emissions from deforestation and forest degradation now constitutes an important strategy for mitigating climate change, particularly in developing countries with large forests. Given growing concerns about global climate change, it is all the more important to identify cases in which economic growth has not sparked excessive forest clearance. We address the recent reduction of deforestation rates in the Brazilian Amazon by conducting a statistical analysis to ascertain if different levels of environmental enforcement between two groups of municipalities had any impact on this reduction. Our analysis shows that these targeted, heightened enforcement efforts avoided as much as 10,653 km2 of deforestation, which translates into 1.44 × 10−1 Pg C in avoided emissions for the 3 y period. Moreover, most of the carbon loss and land conversion would have occurred at the expense of closed moist forests. Although such results are encouraging, we caution that significant challenges remain for Brazil's continued success in this regard, given recent changes in the forestry code, ongoing massive investments in hydro power generation, reductions of established protected areas, and growing demand for agricultural products.  相似文献   

19.
An analysis of the drivers of agricultural land use is important for policy makers as the issues of climate change and food security become increasingly prominent in the political landscape. This paper analyses the role of prices, total land holdings and climate on land use in Australia. The analysis relates to a unique comprehensive coverage of commodity types at a regional level. An explicit treatment of missing data and the novel use of cluster analysis is employed within a partial adjustment framework for modelling land allocation. The majority of commodity types across regions exhibit significant degrees of slow partial adjustment for land allocation, the frequency of slow adjustment is greatest with crops and livestock and weakest for vegetables. In general, relative own and cross prices, total land holdings and rainfall only have a minor impact on short‐term land allocations, however numerous individual commodity/regional combinations have identified significant short‐run impacts.  相似文献   

20.
Given the importance of the agricultural frontier as an engine of deforestation, this paper focuses on how colonists (from the Spanish word for “colonists” that is used to describe migrants to the agricultural frontier), who are important and largely overlooked stakeholders, perceive the new climate mitigation mechanism known as Reducing Emissions from Deforestation and forest Degradation in developing countries (REDD+). We aimed (1) to document colonists’ land use, perceptions, needs, and aspirations and (2) to understand if and how they could be taken into account under REDD+ policies. The study, including multiple data collection techniques (e.g., focus group, interviews, and participatory activities), was conducted in eastern Panama. Three areas that were adjacent to the Province of Darien border were chosen because of their similar forested landscapes and varying accessibility to a main road. Our results suggest that land use preferences, culture, forest scarcity and dependency, inequalities (e.g., land use, amount of forest, and land area), and lack of technical capacities are key elements to be considered when developing a REDD+ strategy with colonist communities. We propose that halting deforestation without both considering local communities’ perceptions and giving effective alternatives could seriously undermine livelihoods.  相似文献   

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