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Deforestation rates in Brazil have undergone an unprecedented decline of more than 70% since 2005. Changes in policies, institutions and social movements provided a platform for this radical slowdown. Moreover, in 2012 a revised version of the Brazilian Forest Code determined that all rural properties in the Amazons should maintain between 50-80% of their area as native forest, known as Legal Reserves (LR), and 100% of the riparian forest. To achieve these targets, deforested properties should subscribe to an Environmental Regularization Plan (PRA). Nevertheless, recent research indicates that biodiversity and carbon storage are still decreasing in areas of eastern Amazonia due to forest fragmentation and degradation. The current government policies and mechanisms are not efficient at incentivizing PRA compliance, nor at connecting forest patches to create a structural network of connected habitats and optimize carbon storage. The Paragominas municipality is one of the oldest frontier towns in this region heading towards agricultural intensification and environmental conservation. We explore land use change scenarios in this area to decrease forest fragmentation while taking into account local economic demands. First, we applied the Functional Land Management framework to assess the spatial variability of three ecosystem services (ES): commodity production, carbon storage and habitat for biodiversity. This assessment was linked to a farm typology based on a survey of 40 farms, to farmers' perceptions on LR and ES using the Q methodology, and to jurisdictional agricultural and environmental policies. Land use changes were modelled in ArcGIS by simulating forest restoration in deforested areas with poor soils, and agricultural intensification on soils suitable for agriculture currently covered by degraded forest. Using FRAGSTAT 3.3 for spatial pattern analysis, we explored landscape scenarios where forest fragmentation decreases as compared to the current status. The goal of these scenarios was to optimize the ...

The Brazilian government aims at augmenting the area cropped under no-tillage (NT) from 32 to 40 million ha by 2020 as a means to mitigate CO2 emissions. We estimated soil carbon (C) sequestration under continuous NT systems in two municipalities in the Goiás state that are representative of the Cerrado. A chronosequence of NT fields of different age since conversion from conventional tillage (CT) was sampled in 2003 and 2011. Soil C levels of native Cerrado and pasture were measured for comparison. After about 11 to 14 years, soil C stocks under NT were highest and at the levels of those under natural Cerrado. Average annual rates of soil C sequestration estimated using the chronosequence approach were respectively 1.61 and 1.48 Mg C ha−1 yr−1 for the 2003 and 2011 sampling, and were higher than those observed using repeated sampling after eight years. The diachronic sampling revealed that the younger NT fields tended to show higher increases in soil C stocks than the older fields. Converting an extra 8 million ha of cropland from CT to NT represents an estimated soil C storage of about 8 Tg C yr−1 during 10 to 15 years.

The Brazilian government aims at augmenting the area cropped under no-tillage (NT) from 32 to 40 million ha by 2020 as a means to mitigate CO2 emissions. We estimated soil carbon (C) sequestration under continuous NT systems in two municipalities in the Goiás state that are representative of the Cerrado. A chronosequence of NT fields of different age since conversion from conventional tillage (CT) was sampled in 2003 and 2011. Soil C levels of native Cerrado and pasture were measured for comparison. After about 11 to 14 years, soil C stocks under NT were highest and at the levels of those under natural Cerrado. Average annual rates of soil C sequestration estimated using the chronosequence approach were respectively 1.61 and 1.48 Mg C ha−1 yr−1 for the 2003 and 2011 sampling, and were higher than those observed using repeated sampling after eight years. The diachronic sampling revealed that the younger NT fields tended to show higher increases in soil C stocks than the older fields. Converting an extra 8 million ha of cropland from CT to NT represents an estimated soil C storage of about 8 Tg C yr−1 during 10 to 15 years.

Throughout Brazil, landless families are being resettled under the government's National Land Reform Program. The corresponding resettlements, the so-called 'assentamentos', constitute for Brazil a new type of small-scale agriculture, the successful development of which promises to be long and challenging. The new settlers encounter a range of technical difficulties related to their limited, heterogeneous knowledge and experience about agricultural production, and to their restricted access to financial resources and institutional support. This paper looks at some of the key characteristics of the farming systems of three assentamentos in the district of Unaí in the Cerrados region, and assesses whether and how conservation agriculture could constitute a viable basis for improving existing crop management practices and for increasing their sustainability and overall contribution to improved household livelihoods. The key problems identified were in order of importance: 1) restricted access to tillage equipment for seedbed preparation; 2) late planting 3) poor weed control; and 4).low soil fertility and restricted access to fertilizers. An approach to participatory development of CA cropping systems is outlined, as well as the first steps taken to test potentially useful CA technologies and to identify and formalize CA focus groups. A major strategy is to articulate research activities conducted with individual farmers to design and adapt CA systems to their specific conditions, and activities conducted with farmers' organizations at the community and regional (participatory evaluation, activity planning, organization of market relationships for inputs and outputs, etc.).

In a continent facing a fast increasing population, smallholder farming in Africa is exposed to double challenge: 1) to increase food production and, 2) to preserve natural resources. While conventional tillage-based agriculture has been held accountable for soil degradation, Conservation Agriculture (CA) based on minimal or no-tillage is increasingly seen as a promising alternative for highly productive and sustainable farming. Despite its potential, CA adoption rates in Africa, compared with other continents, have remained extremely low. While literature on adoption contraints is abundant, comprehensive, holistic frameworks and tools for explaining or predicting adoption are still lacking. In particular, such frameworks and tools could help in assessing systematically under which ecological, socio-economic and institutional conditions CA is best suited for smallholder farming in Africa and for its scaling up. The objective of this contribution therefore is to demonstrate how a newly developed Qualitative expert-based Assessment Tool (QAToCA) was applied in case studies across Malawi, Burkina Faso, and Zimbabwe; 1) to determine the Relative Adoption Potential (RAP) of CA, 2) to assess the institutional, agro-ecological, socio-economic and cultural influences on the RAP of CA, and 3) to determine the site-specific hindering and supporting factors to the RAP of CA for the different case studies. Results show that for the two south African case studies, Malawi has a high RAP for CA while Zimbabwe has a much lower potential. On the other hand the two case studies in south western and northern Burkina Faso both showed a relatively high adoption potential of CA. Major differences in adoption potential are explained by economic market incentives, prevailing institutional arrangements as well as some biophysical incentives.

Forest conservation on privately owned lands is a cornerstone of the Brazilian environmental policy framework. Brazilian legislation requires that all farms in the country maintain and protect forest areas known as Legal Reserves. Since Legal Reserves have major implications for forest conservation and agricultural production, it is key that we understand landholders' perceptions towards Legal Reserves. We applied Q methodology to identify different perspectives of medium and large landholders on Legal Reserves and their relation to agricultural intensification in the municipality of Paragominas, eastern Amazon. We conducted 31 interviews in which landholders sorted 36 statements in a quasi-normal distribution array. Three groups of landholders were identified: 1) Land use planning enthusiasts (n = 16) were interested in zoning initiatives to explore alternative landscape designs and legislation that may deliver better conservation and production outcomes; 2) Agrochemical-based agriculture supporters (n = 7) held the most critical views against Legal Reserves and perceived their costs as higher than the potential environmental and life quality benefits; 3) Policy complacent-market responders (n = 4) showed no interest in Legal Reserves reforms and were the most market driven group. While Paragominas has achieved notable successes in halting large-scale deforestation through a social "Green Municipality" pact, addressing persisting forest degradation and fragmentation in the region remains a key priority. Local governance initiatives that account for multi-stakeholder perceptions on forest conservation can foster dialogue and mutual understanding to effectively conserve and restore Legal Reserves. Insights on large landholders' perceptions on Legal Reserves can inform such governance processes to reconcile forest conservation and sustainable agricultural intensification in Paragominas.

Correspondance: ; National audience ; This paper recalls the principal stages of a French-Brazilian research program on the management of farmers' production risks due to water stress in the Brazilian Cerrados. The objective was to make recommendations to lower the production risks, in terms of both agricultural management practices and insurance policies. An agro-climatic classification at a regional scale allowed for the creation of more efficient credit systems and agricultural insurance coverage, which were mostly beneficial to the large agro-industrial farmers of the region. Subsequently, the case of the smallholder farms was studied by using cropping systems and farm models. The application of these models showed that the risks with which small-scale farmers are confronted are very variable according to the environmental conditions and that they are a limiting factor for a possible intensification of the production. These models, which take into account the constraints specific to the various types of small-scale farms, might be used as a tool for improving existing agricultural insurance systems, particularly in order to better integrate the constraints specific to small-scale farms ; Cet article retrace les principales étapes d'une recherche franco-brésilienne portant sur la caractérisation des risques de stress hydrique dans les Cerrados brésiliens, avec l'objectif de faire des recommandations pour les réduire, à la fois en termes de pratiques culturales et en termes de politique d'assurance agricole. Un zonage agroclimatique à l'échelle régionale a permis d'améliorer le système de crédit de campagne et d'assurance agricole dont bénéficient les grandes exploitations agro-industrielles de la région. Le cas des exploitations familiales a été ensuite étudié en ayant recours à la modélisation des systèmes de culture et des exploitations. L'emploi de ces modèles a montré que les risques auxquels les exploitants sont confrontés sont très variables selon les milieux et peuvent ...

Article en libre accès : http://revues.cirad.fr/index.php/cahiers-agricultures/article/view/30603 ; International audience ; This paper recalls the principal stages of a French-Brazilian research program on the management of farmers' production risks due to water stress in the Brazilian Cerrados. The objective was to make recommendations to lower the production risks, in terms of both agricultural management practices and insurance policies. An agro-climatic classification at a regional scale allowed for the creation of more efficient credit systems and agricultural insurance coverage, which were mostly beneficial to the large agro-industrial farmers of the region. Subsequently, the case of the smallholder farms was studied by using cropping systems and farm models. The application of these models showed that the risks with which small-scale farmers are confronted are very variable according to the environmental conditions and that they are a limiting factor for a possible intensification of the production. These models, which take into account the constraints specific to the various types of small-scale farms, might be used as a tool for improving existing agricultural insurance systems, particularly in order to better integrate the constraints specific to small-scale farms. ; Cet article retrace les principales étapes d'une recherche franco-brésilienne portant sur la caractérisation des risques de stress hydrique dans les Cerrados brésiliens, avec l'objectif de faire des recommandations pour les réduire, à la fois en termes de pratiques culturales et en termes de politique d'assurance agricole. Un zonage agroclimatique à l'échelle régionale a permis d'améliorer le système de crédit de campagne et d'assurance agricole dont bénéficient les grandes exploitations agro-industrielles de la région. Le cas des exploitations familiales a été ensuite étudié en ayant recours à la modélisation des systèmes de culture et des exploitations. L'emploi de ces modèles a montré que les risques auxquels les exploitants sont ...

Cet article retrace les principales étapes d'une recherche franco-brésilienne portant sur la caractérisation des risques de stress hydrique dans les Cerrados brésiliens, avec l'objectif de faire des recommandations pour les réduire, à la fois en termes de pratiques culturales et en termes de politique d'assurance agricole. Un zonage agroclimatique à l'échelle régionale a permis d'améliorer le système de crédit de campagne et d'assurance agricole dont bénéficient les grandes exploitations agro-industrielles de la région. Le cas des exploitations familiales a été ensuite étudié en ayant recours à la modélisation des systèmes de culture et des exploitations. L'emploi de ces modèles a montré que les risques auxquels les exploitants sont confrontés sont très variables selon les milieux et peuvent limiter les possibilités d'intensification. Ces modèles pourraient être utilisés pour améliorer le système d'assurance existant et en particulier pour mieux tenir compte des contraintes propres aux divers types d'exploitations familiales.

Correspondance: ; National audience ; This paper recalls the principal stages of a French-Brazilian research program on the management of farmers' production risks due to water stress in the Brazilian Cerrados. The objective was to make recommendations to lower the production risks, in terms of both agricultural management practices and insurance policies. An agro-climatic classification at a regional scale allowed for the creation of more efficient credit systems and agricultural insurance coverage, which were mostly beneficial to the large agro-industrial farmers of the region. Subsequently, the case of the smallholder farms was studied by using cropping systems and farm models. The application of these models showed that the risks with which small-scale farmers are confronted are very variable according to the environmental conditions and that they are a limiting factor for a possible intensification of the production. These models, which take into account the constraints specific to the various types of small-scale farms, might be used as a tool for improving existing agricultural insurance systems, particularly in order to better integrate the constraints specific to small-scale farms ; Cet article retrace les principales étapes d'une recherche franco-brésilienne portant sur la caractérisation des risques de stress hydrique dans les Cerrados brésiliens, avec l'objectif de faire des recommandations pour les réduire, à la fois en termes de pratiques culturales et en termes de politique d'assurance agricole. Un zonage agroclimatique à l'échelle régionale a permis d'améliorer le système de crédit de campagne et d'assurance agricole dont bénéficient les grandes exploitations agro-industrielles de la région. Le cas des exploitations familiales a été ensuite étudié en ayant recours à la modélisation des systèmes de culture et des exploitations. L'emploi de ces modèles a montré que les risques auxquels les exploitants sont confrontés sont très variables selon les milieux et peuvent limiter les possibilités d'intensification. Ces modèles pourraient être utilisés pour améliorer le système d'assurance existant et en particulier pour mieux tenir compte des contraintes propres aux divers types d'exploitations familiales.

Article en libre accès : http://revues.cirad.fr/index.php/cahiers-agricultures/article/view/30603 ; International audience ; This paper recalls the principal stages of a French-Brazilian research program on the management of farmers' production risks due to water stress in the Brazilian Cerrados. The objective was to make recommendations to lower the production risks, in terms of both agricultural management practices and insurance policies. An agro-climatic classification at a regional scale allowed for the creation of more efficient credit systems and agricultural insurance coverage, which were mostly beneficial to the large agro-industrial farmers of the region. Subsequently, the case of the smallholder farms was studied by using cropping systems and farm models. The application of these models showed that the risks with which small-scale farmers are confronted are very variable according to the environmental conditions and that they are a limiting factor for a possible intensification of the production. These models, which take into account the constraints specific to the various types of small-scale farms, might be used as a tool for improving existing agricultural insurance systems, particularly in order to better integrate the constraints specific to small-scale farms. ; Cet article retrace les principales étapes d'une recherche franco-brésilienne portant sur la caractérisation des risques de stress hydrique dans les Cerrados brésiliens, avec l'objectif de faire des recommandations pour les réduire, à la fois en termes de pratiques culturales et en termes de politique d'assurance agricole. Un zonage agroclimatique à l'échelle régionale a permis d'améliorer le système de crédit de campagne et d'assurance agricole dont bénéficient les grandes exploitations agro-industrielles de la région. Le cas des exploitations familiales a été ensuite étudié en ayant recours à la modélisation des systèmes de culture et des exploitations. L'emploi de ces modèles a montré que les risques auxquels les exploitants sont confrontés sont très variables selon les milieux et peuvent limiter les possibilités d'intensification. Ces modèles pourraient être utilisés pour améliorer le système d'assurance existant et en particulier pour mieux tenir compte des contraintes propres aux divers types d'exploitations familiales.

Cet article retrace les principales étapes d'une recherche franco-brésilienne portant sur la caractérisation des risques de stress hydrique dans les Cerrados brésiliens, avec l'objectif de faire des recommandations pour les réduire, à la fois en termes de pratiques culturales et en termes de politique d'assurance agricole. Un zonage agroclimatique à l'échelle régionale a permis d'améliorer le système de crédit de campagne et d'assurance agricole dont bénéficient les grandes exploitations agro-industrielles de la région. Le cas des exploitations familiales a été ensuite étudié en ayant recours à la modélisation des systèmes de culture et des exploitations. L'emploi de ces modèles a montré que les risques auxquels les exploitants sont confrontés sont très variables selon les milieux et peuvent limiter les possibilités d'intensification. Ces modèles pourraient être utilisés pour améliorer le système d'assurance existant et en particulier pour mieux tenir compte des contraintes propres aux divers types d'exploitations familiales. ; This paper recalls the principal stages of a French-Brazilian research program on the management of farmers' production risks due to water stress in the Brazilian Cerrados. The objective was to make recommendations to lower the production risks, in terms of both agricultural management practices and insurance policies. An agro-climatic classification at a regional scale allowed for the creation of more efficient credit systems and agricultural insurance coverage, which were mostly beneficial to the large agro-industrial farmers of the region. Subsequently, the case of the smallholder farms was studied by using cropping systems and farm models. The application of these models showed that the risks with which small-scale farmers are confronted are very variable according to the environmental conditions and that they are a limiting factor for a possible intensification of the production. These models, which take into account the constraints specific to the various types of small-scale farms, might be used as a tool for improving existing agricultural insurance systems, particularly in order to better integrate the constraints specific to small-scale farms

Forest conservation on privately owned lands is a cornerstone of the Brazilian environmental policy framework. Brazilian legislation requires that all farms in the country maintain and protect forest areas known as Legal Reserves. Since Legal Reserves have major implications for forest conservation and agricultural production, it is key that we understand landholders' perceptions towards Legal Reserves. We applied Q methodology to identify different perspectives of medium and large landholders on Legal Reserves and their relation to agricultural intensification in the municipality of Paragominas, eastern Amazon. We conducted 31 interviews in which landholders sorted 36 statements in a quasi-normal distribution array. Three groups of landholders were identified: 1) Land use planning enthusiasts (n = 16) were interested in zoning initiatives to explore alternative landscape designs and legislation that may deliver better conservation and production outcomes; 2) Agrochemical-based agriculture supporters (n = 7) held the most critical views against Legal Reserves and perceived their costs as higher than the potential environmental and life quality benefits; 3) Policy complacent-market responders (n = 4) showed no interest in Legal Reserves reforms and were the most market driven group. While Paragominas has achieved notable successes in halting large-scale deforestation through a social "Green Municipality" pact, addressing persisting forest degradation and fragmentation in the region remains a key priority. Local governance initiatives that account for multi-stakeholder perceptions on forest conservation can foster dialogue and mutual understanding to effectively conserve and restore Legal Reserves. Insights on large landholders' perceptions on Legal Reserves can inform such governance processes to reconcile forest conservation and sustainable agricultural intensification in Paragominas.

Comments This article is a U.S. government work, and is not subject to copyright in the United States. Abstract Potential consequences of climate change on crop production can be studied using mechanistic crop simulation models. While a broad variety of maize simulation models exist, it is not known whether different models diverge on grain yield responses to changes in climatic factors, or whether they agree in their general trends related to phenology, growth, and yield. With the goal of analyzing the sensitivity of simulated yields to changes in temperature and atmospheric carbon dioxide concentrations [CO2], we present the largest maize crop model intercomparison to date, including 23 different models. These models were evaluated for four locations representing a wide range of maize production conditions in the world: Lusignan (France), Ames (USA), Rio Verde (Brazil) and Morogoro (Tanzania). While individual models differed considerably in absolute yield simulation at the four sites, an ensemble of a minimum number of models was able to simulate absolute yields accurately at the four sites even with low data for calibration, thus suggesting that using an ensemble of models has merit. Temperature increase had strong negative influence on modeled yield response of roughly 0.5 Mg ha 1 per °C. Doubling [CO2] from 360 to 720 lmol mol 1 increased grain yield by 7.5% on average across models and the sites. That would therefore make temperature the main factor altering maize yields at the end of this century. Furthermore, there was a large uncertainty in the yield response to [CO2] among models. Model responses to temperature and [CO2] did not differ whether models were simulated with low calibration information or, simulated with high level of calibration information.