The Brazilian Amazon rainforest is protected largely by command and control regulation of public and private land. The Brazilian Forest Act requires private landholders within the Amazon to set aside 80% of their land as legal reserves for nature protection, but this requirement can be reduced to 50% if more than 65% of a state’s territory is protected public land (for example, public conservation units and indigenous reserves). In the ongoing land designation process in Brazil, some Amazonian states may cross this 65% threshold. We assess the potential reduction in the legal reserve requirement from 80% to 50%, through spatially explicit modelling of scenarios concerning land tenure consolidation, employing up-to-date databases on land ownership. Depending on the outcome of land designation processes and political priorities, some 6.5–15.4 million hectares of private land previously protected as legal reserves may become available for legal deforestation. While protection of public land is crucial for safeguarding the Amazon, revisions of federal and state legislation may be needed to avoid the further extension of protected public land triggering increased legal deforestation on private lands. Zero-deforestation commitments and other initiatives may mitigate impacts in the absence of such revision.
Public conservation policies are essential for protecting ecosystem services and biodiversity from impacts associated with deforestation in the Amazon rainforest1,2,3,4,5, driven by agricultural expansion, mining activities, land grabbing and infrastructure development4,6,7,8. Full implementation of the existing Brazilian legal framework for forest protection on private and public land could ensure the protection of 95% of the remaining Amazon rainforest and almost 90% of the entire Amazon biome in Brazil3.
Key to achieving this level of protection is the Brazilian Forest Act9, which requires that 80% of privately owned land in the Amazon region be protected as legal reserves (LR) for native vegetation protection. However, Article 12/§5 of the Forest Act allows state public authorities to reduce this legal requirement from 80% to 50% if more than 65% of the state’s territory is covered by conservation units or indigenous reserves (CU&IRs). Unlike other provision introduced in the 2012 revision of the Forest Act, providing amnesty for 32–41 Mha of illegal native vegetation land conversion that occurred prior to 20081,9,10 (see Supplementary Table 1), Article 12/§5 allows future LR reductions on private land that is still covered with forests, leading to reduced forest protection and allowing more legal deforestation in the Amazon region.
A previous study evaluated the potential for this provision in Article 12/§5 to trigger a reduction in the LR requirements, but found that no Brazilian states qualified for this reduction (considering the available databases in 2014)1. Despite recent setbacks6,11, Brazil has since continued to expand the demarcation of CU&IRs, and more are likely to be created during the titling of undesignated public land in the Amazon biome12. The areas protected as CU&IRs may therefore exceed the 65% threshold in several states, unlocking the legal instrument for reducing forest protection on private land.
The implications of triggering Article 12/§5 are somewhat conjectural because its application will depend on a combination of political priorities and decisions made by different stakeholders at different administrative levels. The likelihood and impacts of triggering Article 12/§5 mainly depend on the designation of the roughly 80 Mha of undesignated land13 where land rights are currently uncertain12. Undesignated land is frequently subject to illegal land appropriation and often a source of dispute among indigenous people, farmers and conservationists. In the coming years, such territories may be titled as private land, or designated for conservation through the creation of new CU&IRs13,14. States such as Amazonas, Roraima, Acre and Amapá are largely covered with native vegetation and have extensive areas of undesignated land. Expansion of CU&IRs in these states is likely, and much needed to ensure the preservation of Amazonian nature12. However, an expansion of CU&IRs may also have unintended consequences. By triggering Article 12/§5, it would allow these states to reduce the LR requirement on private lands from 80% to 50%, opening up large areas for legal deforestation and agricultural expansion.
Here, we assess the potential impacts of this reduction in LRs using the Land Use Governance Assessment (LUGA) model, a spatially explicit model that combines land tenure datasets for conservation units, indigenous reserves, military land and boundaries of private rural properties, and so on, with simulations of rural property boundaries in regions where no tenure datasets are available (see Freitas et al.3 for details). We model the implementation of Article 12/§5 in two scenarios that consider diverging patterns for the destination of currently undesignated land in the Amazon region: (1) a Conservative (CON) scenario where nature protection is a high priority, and (2) a Worst-Case (WC) scenario (from the perspective of nature protection), that maximizes the LR reduction resulted from the implementation of Article 12/§5. We quantify the potential reduction in forest protection in these scenarios by assessing the risks for legal conversion of no longer protected land to agricultural use, using measures of land suitability and market access, as well as potential impacts from such land conversion in terms of carbon emissions and biodiversity protection. The principle for designation of currently undesignated land is based on native vegetation coverage in undesignated polygons in the land tenure dataset.
Potential reduction in the protection of native vegetation
Our results suggest that in both the CON and WC scenarios, three Brazilian states would qualify for reducing their LRs as described in Article 12/§5: Amazonas, Roraima and Amapá (Fig. 1). Under the CON scenario, 97% of the undesignated territory of Amazonas and Amapá, and 86% in Roraima, would be assigned to CU&IRs. In this scenario, Article 12/§5 would remove the protection of 6.5 Mha of preserved forest (4.6 Mha in Amazonas, 1.4 Mha in Roraima and 0.5 Mha in Amapá), storing a total of 0.8 Gt of carbon in above-ground biomass (Fig. 1).
Naturally, the more land that is allocated to CU&IRs, the greater the area of protected land, that is, until a state reaches the 65% threshold. When CU&IRs within the state reach the 65% threshold value, Article 12/§5 is triggered and the area of unprotected forest is more than doubled. Figure 2 shows the estimated unprotected forest, assuming a gradual increase in the percentage of undesignated land assigned to CU&IRs. Maximum loss in protection due to Article 12/§5 (the WC scenario) occurs when 35% of the undesignated territory in Amazonas is assigned to CU&IRs, compared with 42% in Roraima and 0% for Amapá state. Because Amapá already qualifies for reducing LRs, the worst case in Amapá occurs when no additional CU&IRs are created, and all undesignated territory is assigned to private use. In this WC scenario, over 15 Mha of preserved forest on private land, holding almost 2 Gt of carbon in the above-ground biomass, would lose legal protection across all states (12 Mha in Amazonas, 2 Mha in Roraima and 1 Mha in Amapá; see Fig. 1). In both scenarios, more than 70% of the land eligible for Article 12/§5 LR reductions would be in areas prioritized for biodiversity conservation, with more than half of it defined as of extremely high importance for biodiversity conservation (Fig. 1).
Figure 2 shows the net change in unprotected forest after Article 12/§5 is triggered. In Amazonas state, there would be a net increase in unprotected forest after triggering Article 12/§5 when 35% to 81% of the undesignated territory is assigned to CU&IRs, and a net decrease when 81% or more is assigned to CU&IRs. On the other hand, in Roraima state there will always be a net increase in unprotected forest if more than 42% of the undesignated territory is assigned to CU&IRs.
Rural properties qualifying for Article 12/§5
In the CON scenario, about half (3.14 Mha) of the reduction in forest protection would occur on private properties registered in the national registries of rural properties (Fig. 1). About 1.9 Mha of the reduction would occur in agrarian reform settlements and another 0.6 Mha on properties expected to be titled during the designation of undesignated land. In the WC scenario, most of the reduction would take place in currently undesignated territories, where newly titled properties would have their LRs reduced by more than 8 Mha.
Figure 3 shows the rural properties qualifying for Article 12/§5, as well as their relative agricultural suitability and market access. In comparison to consolidated properties, Article 12/§5-qualifiable properties have greater average suitability for agricultural uses. This indicates that there are no (or few) edaphoclimatic restrictions on agricultural expansion in these regions. Nevertheless, most of the properties qualifying in both scenarios are in remote areas where transportation costs to markets are high. Even so, considering existing logistics infrastructure and current location of markets for beef and soybean, roughly 1.8 Mha and 3.7 Mha would face considerable land conversion pressure in the CON and WC scenarios, respectively, exhibiting land suitability and market access similar to or greater than that of existing consolidated rural properties.
Our findings suggest that tenure consolidation in the Amazon region could qualify thousands of private properties for the reduction in LRs described in Article 12/§5, effectively reducing forest protection on private land. This includes over 40,000 registered rural properties and an additional several thousand rural properties expected to be created during the titling of undesignated land. Amapá state already qualifies for Article 12/§5 because CU&IRs now represent about 70% of the state territory. Most of Article 12/§5-qualified properties are found in remote regions in the Amazon, although a considerable share of these properties is within a reasonable distance from dominant agricultural industries. In the absence of legal protection, forests may be legally converted to agricultural land uses. Furthermore, recent and future development of road infrastructure and the expansion of the beef and soybean sectors in the region could reduce transportation costs and make additional Article12/§5-eligible properties subject to agricultural expansion.
The main argument in this paper rests on the expansion of CU&IRs, triggering Article 12/§5. However, strong forces within the Brazilian government are pushing for repealing or downsizing CU&IRs to free up land for mining exploitation, infrastructure development and agricultural expansion6,11. Presidential Decree no. 9147, abolishing 4 Mha of conservation units in the Pará and Amapá states, is one clear example. This decree was revoked after strong criticism but arguably remains viable, pending more favourable political conditions.
The implications of downsizing CU&IRs for the implementation of Article 12/§5 are ambiguous. Downsizing CU&IRs may prevent some states from qualifying for Article 12/§5, therefore avoiding any further reduction in LR requirements on private land derived from Article 12/§5. On the other hand, creating large new areas of CU&IRs in remote regions of the Amazon, while downsizing CU&IRs close to productive infrastructure (for mining or agricultural production) could still trigger Article 12/§5 if the net change surpasses the 65% threshold. This could even boost environmental impacts considering that more properties qualifying for Article 12/§5 LR reduction would be within zones of high deforestation pressure.
Only public CU&IRs can be considered in an evaluation against the 65% threshold. While most CU&IRs are publicly owned, Environmental Protection Areas (EPAs), a subset of CU&IRs representing almost 30% of all conservation units in Brazil, can be privately or publicly owned. Available databases do not permit accurate identification of the extent of EPA land that is publicly and privately owned. This information may be critical for determining whether other states could qualify for the Article 12/§5 reduction in LRs. One example is Pará state, where the potential impact of reduced LR requirements on private land could be considerable.
Despite the fact that Article 12/§5 has not yet been implemented in practice, the legal procedures are well defined. The administrative and legal pathway toward Article 12/§5 can nearly all be solved at state level through the establishment of a regulatory act (that is, Decree) in consultation with the state’s Environmental Council and in alignment with the Ecological-Economic Zoning. The composition of the state’s Environmental Council is mostly influenced by the state’s government, who is also responsible for the elaboration of the Ecological-Economic Zoning. Thus, if the state government in any of the states of Amapá, Rorâima or Amazonia are positive towards an implementation of Article 12/§5, it will probably not face any significant administrative obstacles and can proceed without external formal influence.
Furthermore, recent developments in environmental legislation converge towards the implementation of Article12/§5 and raise concerns regarding its potential impacts. The Brazilian Federal Supreme Court has recently acknowledged the constitutionality of Article 12/§515, giving legal security to this regulation. In addition, despite strong opposition by conservationists, Act 13.465/201716 was enacted by the Brazilian government to facilitate the titling process of large undesignated rural properties within the Legal Amazon region. This new regulation provides legal ground for the conversion of public undesignated land into large private rural properties that, in the long run, may qualify for the reduction in legal protection described in Article 12/§5.
The preservation of the Amazon forest is highly dependent on the immediate creation of new CU&IRs on undesignated land, considering that this is the most cost-effective way to prevent deforestation12,17,18,19. However, possible consequences of triggering Article 12/§5 need to be considered. Attention should be given to the potential losses in protected areas on private land eligible for LR reduction according to Article 12/§5, considering their importance for conserving biodiversity and upholding essential ecosystem services.
Mitigation of the potential impacts of implementing Article 12/§5 will depend on public and private policies that go beyond the legal requirements for preventing deforestation. Environmental impact assessments of future infrastructure development and agroindustry expansion in the Amazon should carefully consider impacts of a possible implementation of Article 12/§5 on biodiversity and climate change. Zero-deforestation commitments and other initiatives that facilitate native vegetation protection beyond legal requirements will remain crucial for nature protection in the Amazon region2,20,21. Such initiatives need not constrain agricultural growth. There is significant scope for improving land-use efficiency and thereby increasing production on existing agricultural land22,23,24,25. Furthermore, alternative development pathways for the Amazon region can be more promising economically and more sustainable socially and environmentally26,27,28,29.
Our analysis covers the Legal Amazon, an administrative region of Brazil created in 1948 to promote economic and social development of states sharing the Amazon rainforest. The region comprises the states of Acre, Amazonas, Pará, Amapá, Roraima, Mato Grosso, Tocantins and Rondônia, and the part of Maranhão west of meridian 44° W. The analysis was limited to the Legal Amazon because the reduction in LRs described in Article 12/§5 is only applicable in this region9. However, in the case of Maranhão we computed CU&IRs located in the entire state, considering that the 65% threshold is relative to the entire state territory.
The LUGA model
The implementation of Article 12/§5 of the Brazilian Forest Act is related to other mechanisms regulating native vegetation protection on private land1,9,10,30,31, summarized in Supplementary Table 1. To model the implementation of Article 12/§5, including its interactions with other mechanisms, we employed the LUGA model3, a spatially explicit modelling framework that enables an integrated assessment of various mechanisms of land-use protection in Brazil13.
The LUGA model is divided into two major steps: (1) simulation of consolidated land tenure and (2) allocation of land for compliance with the regulatory framework for native vegetation protection. The core output is a pixel-level assessment of public governance regulations to protect native vegetation.
The Brazilian Forest Act comprises rules and regulations that differ depending on a broad set of conditions related to land tenure, biome type and property size. However, Brazil lacks a reliable nationwide dataset of rural properties32. Despite substantial improvements brought about recently by the Rural Environmental Registry33, a considerable part of its territory is under some form of dispute with unclear tenure status14. To model tenure consolidation across the Legal Amazon, we employed the most recent tenure dataset by Freitas et al.34, which combines various datasets on land tenure (for example, conservation units, indigenous reserves, military land and boundaries of private rural properties) and simulates rural property boundaries in regions where no tenure datasets were available (see Freitas et al.3 for details). In this study, we updated the above-mentioned dataset by subdividing large polygons classified as undesignated land into smaller polygons using Voronoi diagrams. This process was carried out so that the final distribution of polygon sizes resembles the size distribution for registered rural properties in the region.
The allocation of land for compliance with the Brazilian Forest Act was carried out based on the procedure addressed in previous studies1,3,13, considering the legal instruments described in Articles 4 and 61-A for allocation of Permanent Preservation Areas, and Articles 13, 15 and 67 for the allocation of land protected as a LR. A summary is available in Supplementary Table 1.
Modelling the implementation of Article 12/§5
To our knowledge, no existing database enables a precise spatial identification of the undesignated territory in the Legal Amazon. Here we defined undesignated lands as the portion of the Amazon region where absolutely no tenure information could be found, represented by the simulated tenure class in the land tenure dataset34. We acknowledge that this approach may misclassify private properties not yet registered in any tenure database as undesignated land. However, this error is probably small given that the territory classified as undesignated is concentrated in the most remote regions of the Amazon, where public undesignated lands are most common. Moreover, the undesignated lands identified in this analysis largely agree with the Brazilian Forest Service’s undesignated public forest layer12. Yet we chose not to use the latter layer because it does not cover all the undesignated land in the Amazon, only the part that has been officially mapped by the Brazilian Forest Service. Further, much of the forest classified as undesignated has already been assigned to public conservation or to private use.
To estimate the potential reduction of protected forest, we modelled the implementation of Article 12/§5 under two contrasting scenarios. The CON scenario includes a set of assumptions concerning the allocation of undesignated land to private use and public conservation, as described in Sparovek et al.13. In this scenario, undesignated polygons in the land tenure dataset are assigned to private land if native vegetation coverage is below 95%, and to CU&IRs if the native vegetation is above 95%. This approach allocates private land where there is already some level of human appropriation for agricultural use. The 95% threshold value is a rough approximation of the native vegetation coverage observed in the existing public protected areas. We consider this a conservative scenario because it assumes that regions fully covered by native vegetation will always be assigned to public conservation, and only regions under some level of agricultural use may be assigned to private use.
The alternative WC scenario identifies the conditions under which the reduction in forest protection on private land in the Amazon region is maximized, as permitted by the full implementation of Article 12/§5. This was achieved for each state by assigning undesignated land to CU&IRs until the total area of CU&IRs corresponded to 65% of the state territory, the threshold value for Article 12/§5 qualification. All remaining undesignated land was then subsequently designated as private land. This was done by first geographically allocating private land to regions with lower native vegetation coverage and greater agricultural occupation. Second, we prioritized the allocation of CU&IRs to areas where there is no mining interest, considering that the creation of new CU&IRs could be opposed by such interests.
Indicators of land suitability and market access
To evaluate the deforestation pressure on Article 12/§5-qualifiable properties (defined as rural properties or simulated properties that may qualify for the reduction in LRs described in Article 12/§5), we evaluated the properties in relation to land suitability and market access. For this purpose, we used two generic indicators of land suitability and market access as described below.
Land suitability indicator
The land suitability indicator was constructed to demonstrate land suitability for agricultural use, taking into consideration edaphoclimatic conditions that are favourable for the dominant agricultural activities, such as pastures, soybean production and plantation forestry. This indicator considers attributes related to soil, terrain and climate. Soil attributes consisted of datasets (250 m spatial resolution) on soil fertility, drainage, texture and depth, derived from the global gridded soil information (SoilGrids database35). Terrain attributes consisted of slope (30 m spatial resolution), extracted and resampled from the digital elevation model from the Shuttle Radar Topography Mission36. Climate attributes consisted of the WORLDCLIM datasets37 including monthly averages of temperature, precipitation and solar radiation (1 km spatial resolution). The input variables and the work flow are illustrated in Supplementary Table 2 and Supplementary Fig. 1, respectively.
Market access indicator
As a proxy for market access, we estimated the transportation cost from each cell to the destinations of dominant commodities driving land-use change, such as soybean and beef. This was done using ArcGIS38 Cost Distance Analysis, which uses Cost Raster and Source Data as inputs. Cost Raster is a dataset that defines the planimetric cost to move from one cell to the other. Here, we used a generic Cost Raster from Englund et al.39, who estimated the cost to traverse different surfaces in Brazil based on a literature review. The input Source Data (destination of agricultural products) included the location of existing slaughterhouses, soybean industries, and international ports in Brazil and Peru. The final output of transportation cost was inverted and then normalized to a scale of 0 to 1, where ‘1’ indicated the lowest cost (highest level of market access) and ‘0’ the highest cost (lowest level of market access). Supplementary Table 3 and Supplementary Fig. 2 present the input databases and the processing flow, respectively, used to generate the market access indicator.
Evaluation of potential deforestation pressure
We assessed the potential deforestation pressure on Article 12/§5-qualifiable properties by analysing their distribution relative to market access and land suitability, compared with the distribution of consolidated rural properties. Consolidated rural properties were defined as those: (1) registered in CAR33 or SIGEF rural property registries40, (2) located within the forest vegetation type41 in the Legal Amazon, and (3) having less than 50% of preserved native vegetation.
We calculated the average value of land suitability and market access indicators for each consolidated rural property as well as for Article 12/§5-qualifiable rural properties in the CON and WC scenarios. Each model output from this process was then used as input to a kernel density estimation (KDE). We identified the portion of Article 12/§5-qualifiable properties that could be under deforestation pressure if Article 12/§5 was implemented, based on the assumption that a given rural property will be under deforestation pressure if land suitability and market access is similar to, or greater than, that of consolidated rural properties.
Impacts on carbon stocks and biodiversity
To calculate the potential loss of above-ground carbon stocks, the total area of forest that would lose protection under Article 12/§5 was multiplied by the average above-ground carbon content in the native forest of a given rural property. Carbon densities for Article 12/§5-qualifiable properties were obtained from the carbon map by Englund et al.42.
We overlaid the Article 12/§5-qualifiable properties with priority areas for biodiversity conservation43 to identify potential impacts of Article 12/§5 in high biodiversity areas. The map of priority areas was produced by the Brazilian government, following the framework proposed by the United Nations Convention on Biological Diversity. This map was generated through a multi-stakeholder process based on up-to-date databases, considering various factors such as species richness, the occurrence of endemic and threatened species, the presence of rare biological phenomena, the cost of conservation, and the importance for biological processes43.
All input datasets used to conduct our analysis are publically available from the cited references. Raw data associated with figures in this manuscript as well as intermediate files are available from the corresponding author upon request.
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We would like to express our appreciation to L. Fernando Guedes Pinto and V. Guidotti, who revised this manuscript, providing comments and suggestions that helped us improve the article. We are also grateful to the Brazilian National Council for Scientific and Technological Development (CNPQ, grant no. 249404/2013-3) and the São Paulo Research Foundation (FAPESP, grant no. 2016/17680-2) for financing this research.