Finisterra, LXI(131), 2026, e41854

ISSN: 0430-5027

doi: 10.18055/Finis41854

Artigo de Investigação

LEGAL EVOLUTION OF LAND USE IN PERMANENT PRESERVATION

AREAS IN TWO MUNICIPALITIES IN THE NORTHEASTERN BRAZILIAN

COAST:

A PROPOSAL FOR REFORMULATING THE LEVEL OF PROTECTION OF COASTAL

ECOSYSTEMS

IDEVAN GUSMÃO SOARES¹

SARAH ANDRADE SAMPAIO¹

REGINA CÉLIA DE OLIVEIRA¹

ABSTRACT – The preservation of coastal zones in tourist regions is essential for maintaining sensitive ecosystems

and ensuring socioeconomic sustainability. Internationally significant destinations along the northeastern Brazilian coast face

increasing anthropogenic pressures and legislative gaps that threaten their ecological integrity. This article examines the legal

evolution of Brazil’s Forest Codes (Laws 4.771/1965, 7.511/1986, and 12.651/2012), focusing on coastal areas, and

compares two municipalities with distinct coastal dynamics and types of Permanent Preservation Areas (PPAs): Barreirinhas

(Maranhão) and Valença (Bahia). The methodology included: (I) a theoretical review; (II) analysis of the legal framework;

(III) PPAs mapping in accordance with legal criteria; and (IV) a comparative land-use analysis (1990-2023) using

MapBiomas data. The results show divergent trends: in Barreirinhas, the PPAs reduced their area from 677.5km² to 649.6km²

(-4%), while anthropogenic activities (agriculture, urbanization, and bare soil) increased from 27.7km² to 30.3km² (from 10%

to 13.3%). In Valença, the PPAs expanded their area from 161.1km² to 228.6km² (42%); however, inadequate land uses

within protected areas also increased, indicating weaknesses in conservation effectiveness. The study concludes that PPA

delineation must integrate hydrological, ecological, and ecosystem-based criteria, including salt flats, saline areas, mobile

dunes, and riparian zones at the national level. This approach, supported by global scientific evidence, is urgently needed to

preserve critical coastal ecosystems, particularly in high-impact tourism regions.

Keywords: Tourist regions; protected areas; forest codes; conflicts.

RESUMO – EVOLUÇÃO LEGAL DO USO DA TERRA NAS ÁREAS DE PRESERVAÇÃO PERMANENTE EM

DOIS MUNICÍPIOS DA ZONA COSTEIRA DO NORDESTE BRASILEIRO: UMA PROPOSTA DE READEQUAÇÃO

DO NÍVEL DE PROTEÇÃO DE ECOSSISTEMAS COSTEIROS A preservação de zonas costeiras em regiões turísticas é

fundamental para a manutenção de ecossistemas sensíveis e a sustentabilidade socioeconômica. Destinos de relevância

internacional no litoral do Nordeste Brasileiro enfrentam pressões antrópicas crescentes e lacunas legislativas que ameaçam

sua integridade ecológica. Este artigo examina a evolução legal dos Códigos Florestais (Leis n.º 4.771/1965, 7.511/1986 e

12.651/2012) com foco na zona costeira do Brasil, considerando dois municípios com diferentes dinâmicas litorâneas e tipos

de Áreas de Preservação Permanente (APPs), Barreirinhas (Maranhão) e Valença (Bahia). A metodologia incluiu: (I) revisão

teórica; (II) análise do marco legal; (III) mapeamento de APPs conforme critérios legais; e (IV) análise comparativa do uso

do solo (1990-2023) com dados do MapBiomas. Os resultados revelam tendências divergentes: em Barreirinhas, as APPs

reduziram sua área de 677,5km² para 649,6km² (-4%), enquanto atividades antrópicas (agropecuária, urbanização e solo

exposto) aumentaram de 27,7km² para 30,3km² (de 10% para 13,3%). Já em Valença, as APPs expandiram sua área de

161,1km² para 228,6km² (42%), assim como os usos inadequados no interior das áreas protegidas também aumentaram,

indicando fragilidades na efetividade da proteção. Conclui-se que a delimitação de APPs deve integrar critérios hidrológicos,

ecológicos e ecossistêmicos, incluindo apicuns, salgados, dunas móveis e zonas ripárias em âmbito nacional. Essa

abordagem, respaldada por evidências científicas globais, é urgente para conservar ecossistemas costeiros críticos,

especialmente em regiões turísticas de alto impacto.

ꢀ

Palavras-chave: Regiões turísticas; áreas protegidas; códigos florestais; conflitos.

HIGHLIGHTS

•

Innovative proposal to include coastal sub-ecosystems as new PPAs.

Land use disrespects the law in PPAs of two coastal municipalities in NE.

An innovative study proposes the recognition of salt flats, saline areas and mobile dunes as

PPAs.

•

Legal loopholes were traced in the management of PPAs in coastal areas of Brazil.

Recebido: 30/07/2025. Aceite: 12/02/2026. Publicado: 10/04/2026.

Idevan Gusmão Soares: idevanoficial@gmail.com

¹Department of Geography, Institute of Geosciences, University of Campinas, R. Carlos Gomes, 250 - University City, 13083-855, Campinas - São Paulo,

Brazil.

Published under the terms and conditions of an Attribution-NonCommercial-NoDerivatives 4.0 International license.

Soares, I. G., Sampaio, S. A., Oliveira, R. C. Finisterra, LXI(131), 2026, e41854

1.

INTRODUCTION

The notion of protecting areas that are representative of natural ecosystems in Brazil’s territory dates

back to the 1934 Forest Code (República Federativa do Brasil, 1934). This Code included preservationist

aspects, regulating property use based on the type of forest present and defining categories such as

protective forests, remnants, and protective models of agrarian production. The concept of Permanent

Preservation Areas (PPAs), which is the main protected area established by law in Brazil, was only

instituted by the Forest Code (Law. 4.771) in 1965 (Borges et al., 2011).

The legal evolution of the Brazilian Forest Code underwent implementations until 2012, becoming

more explanatory, in an attempt to reduce dubious interpretations of the law, as well as imposing more

restrictions on private property, addressing the need to maintain and protect PPAs and Legal Reserve areas.

Before the publication of this Code, few regulations protected environmental resources on rural properties

in the Brazilian territory.

However, despite a significant evolution of legal provisions, such as the National Council for the

Environment (CONAMA) Resolutions (República Federativa do Brasil, 1986, 1997, 2002, 2007) that

address specific aspects of environmental legislation and establish rules for its application and inspection,

several environmental researchers, as well as politicians and governors who advocate the cause, argue for

bills that indicate the need to establish more effective criteria for PPAs at the national level.

Theoretically, the issue that this work intends to address fits into an analysis of the level of

protection of PPAs in the Brazilian coastal zone; notably, there is a discrepancy in the level of protection,

to the detriment of the interior environments of the territory. Advocating authors such as Pinheiro et al.

(2013), Pinheiro, Moura-Fé and Freitas (2013), Zanatta et al. (2014), Albuquerque et al. (2015), and

Bonzanini and Lupinacci (2023), among others, argue that some ecosystem delimitation criteria in the

current legislation are not sufficient to cover coastal environments considering their intense dynamics of

change, areas of high international importance, in the ecological, economic and socio-cultural scope.

The studies by Pinheiro et al. (2013) and Pinheiro, Moura-Fé, and Freitas (2013) converge in

highlighting a structural weakness in Brazilian environmental legislation regarding the protection of coastal

ecosystems, especially the dune system. The authors emphasize that Law 12.651/2012, by not recognizing

mobile dunes as PPAs and by fragmenting the dune ecosystem into isolated features, disregards its

ecological, geomorphological, and landscape complexity. Based on detailed analyses of legal texts and

consistent scientific evidence, the studies demonstrate that this regulatory gap favors processes of irregular

occupation and environmental degradation, particularly in coastal areas subjected to intense anthropogenic

pressures. As a result, the authors argue for the need to classify dunes as an integrated and legally protected

ecosystem, under penalty of irreversible loss of this natural heritage.

This critique of legal fragmentation is also central to the study by Albuquerque et al. (2015), which

addresses the mangrove ecosystem. Analogously to the case of dunes, the authors point out that the Forest

Code protects only mangrove vegetation, allowing uses considered "ecologically sustainable" in salt marsh

and salt flat areas, despite their functional interdependence. The analysis shows that such a legal distinction

ignores the ecological dynamics of the mangrove as an integrated system, opening the door to uses

incompatible with its conservation. The results indicate that sectoral protection compromises the

effectiveness of environmental legislation, especially in historical and current contexts of intensive land

use, contributing to the progressive degradation of these sensitive environments.

The works of Zanatta et al. (2014) and Bonzanini and Lupinacci (2023) further deepen the

discussion by empirically demonstrating the effects of environmental legislation on continental areas,

directly relating legal norms, land use, and environmental degradation. In the study of the Areia Dourada

stream basin, it is evident that the 1965 Forest Code offered greater compatibility with natural dynamics,

ensuring significantly broader territorial protection than that provided for in current legislation, whose

reduction of PPAs exacerbates land use conflicts and environmental pressures.

Complementarily, the analysis of the upper Cabeça river basin reveals the recurring non-compliance

with PPAs and Legal Reserves, with the replacement of native vegetation by agricultural activities,

intensifying erosion processes, siltation, and loss of soil fertility. Taken together, these studies reinforce the

idea that weakened regulations and ineffective enforcement of environmental legislation have directly

contributed to the increased degradation of ecosystems, highlighting the need for a conceptual and practical

review of environmental protection policies in Brazil.

Research on federal environmental legislation is not restricted only to Brazil; internationally, several

scientific studies focus on this issue, including studying the impacts of tourism on nature. In Russia,

Zazolína (2025) analyzed the current environmental legislation. In this study, the author emphasizes that

the numerous legislative acts at various levels significantly complicate both the implementation of

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Soares, I. G., Sampaio, S. A., Oliveira, R. C. Finisterra, LXI(131), 2026, e41854

environmental standards and legal enforcement practices. One of the main factors contributing to these

challenges is identified as the absence of a unified codified legal act – i.e. the Environmental Code of the

Russian Federation. It also notes the legislators’ lack of attention to the natural and climatic specificities,

among other factors, in the process of drafting environmental codes.

The study conducted by Díaz Duque et al. (2025) in Cuba followed the same premise of the

aforementioned Russian author, emphasizing the deficiencies in several problems traced by specialists in

issues such as the environmental documents that govern the country, the approach to sustainability in

government management and legislation, among other issues related to environmental policy and

management.

The concern about the pressure of tourism on natural resources was studied by Ziari and Mosleh

(2025) in the northern region of Tehran, Iran. Similarly, to the objective of this article, these authors also

resorted to a multi-temporal analysis (1985-2022) to show the environmental changes and degradations

resulting from land use. By tracing key factors contributing to environmental degradation, such as irregular

construction and changes in land use, the research provided practical insights for policymakers. In the study

conducted by Abbas (2023) in Pakistan, the author emphasized the strong relation between tourism

development and environmental deterioration in that country.

As an example, a significant challenge in protecting the Brazilian coast is posed by the exclusion of

ecosystems that are strategic in the regulation of coastal environments – such as mobile dunes, sandspits,

salt flats, leached soils, and saline areas – from the regime of PPAs, which is justified by the lack of

significant vegetation cover. Considering this regulatory gap, this study offers substantive contributions

toward the advancement of scientific knowledge in coastal environmental management. The proposed

approach demonstrates potential to redefine PPAs delimitation criteria, incorporating geomorphological

and ecological parameters compatible with the dynamics of protection of coastal systems.

Therefore, the objective of this study is to trace the legal evolution of the Forest Codes (Law

4.771/1965, Law 7.511/1986 and Law 12.651/2012), focusing on the coastal zone of Brazil’s Northeast

region, by comparing two municipalities with different dynamics of coastal functioning and different types

of PPAs. After tracing the legal evolution aspects, we compared two land cover contexts in the PPAs of

said laws, in the contexts of 1990 and 2022, to understand the impact of changes in the dynamics of land

use and determine the legal status of use in PPAs in relation to changes in environmental legislation in

different coastal environments.

2.

METHODOLOGY

2.1

Characterization of study areas

We selected two tourist municipalities in the coastal zone of northeastern Brazil (fig. 1). Brazil’s

northeastern coast is a region of major geographical relevance, characterized by a diversity of coastal

formations that vary in their different units of the federation. Notably, these include Maranhão and Bahia,

which, in addition to having the largest coastlines in Brazil’s Northeast region, have distinct environmental

characteristics. Maranhão, located on the northern coast of Brazil, has a coastline marked by extensive

areas of dunes, deltas, tablelands, mangroves and restingas, reflecting a geomorphological environment of

transition between the equatorial climate and the tropical zone (Lima et al., 2023). In turn, Bahia, which is

part of the Eastern Coast, has a coast characterized by ample environments of mangroves, reefs, beaches

with extensive coasts and cliffs, with a strong influence of the humid tropical climate (Silva & Silva, 2007).

The physical and hydrographic dynamics of these two regions are different due to the variations in

rainfall regime, characteristics of sea currents and behavior of tides. The Northern Coast of Brazil is

strongly influenced by sediment deposition processes, resulting from low wave energy, which favors the

development of large estuarine systems and mangroves, with water dynamics that is characteristic of areas

with low slope. The coastal zone of Maranhão has a low coast domain, configuring an intense and

prolonged sedimentary deposition, from the Cretaceous, followed by the continuous remobilization of this

same material by morphogenetic agents, a phenomenon that is still regular with high frequency throughout

its length, which originated three gradually differentiated coastal segments, namely: rectilinear, sandy

coast, to the east that surrounds the municipality of Barreirinhas; coast of recesses, mud, to the west; and

mixed coast, exhibiting aspects of the two systems, in the recess of the Golfão Maranhense (Feitosa &

Souza, 2015).

The municipality of Barreirinhas, located in the state of Maranhão, Brazil, is known for being the

gateway to Lençóis Maranhenses, one of the most important National Parks in the country, famous for its

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vast dunes without vegetation cover, white sand and crystal-clear water lagoons that form during the rainy

season, whose local economy is strongly influenced by tourism, in addition to fishing and agriculture.

Study Areas

Fig. 1 – Study areas: Municipalities of Barreirinhas (MA) and Valença (BA).

Fig. 1 – Áreas de estudo: Municípios de Barreirinhas (MA) e Valença (BA).

Source: IBGE (2022)

Due to the remarkable, internationally recognized scenic beauty of Lençóis, the municipality of

Barreirinhas has received a significant number of tourists in recent years, which has impacted the local

infrastructure and economy, since it has a relatively small population, with 65 589 inhabitants in a

territorial area of 3 046 308km² (Instituto Brasileiro de Geografia e Estatística [IBGE], 2022a).

The municipality of Barreirinhas, the main gateway to the Lençóis Maranhenses National Park,

recorded 76 666 visitors in September 2025, according to the Informative Bulletin of the Maranhão

Tourism Observatory (Obstur-MA), representing an increase of 56.28% compared to the same period in

2024, thereby consolidating the destination as one of the most sought-after in the state of Maranhão and a

symbol of the advancement of tourism planning in the region (Maranhão, 2025).

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Given its physical aspects, it is worth mentioning that Barreirinhas has its territory drained

predominantly by the Preguiças river basin and is located in the Cerrado biome, where characteristic

vegetation cover can be identified, such as the wooded and forested savannas in the rural area of the

municipality (IBGE, 2023a).

As it is located in the region of the Maranhão coast, it has specific vegetation and geomorphological

features such as restingas, mangroves, salt flats, and mobile dunes. The climate type is humid tropical, with

a rainy season beginning in January and ending in June and drought from July to December. The average

annual temperature is above 27°C and total rainfall ranges between 800 and 2 000mm (Instituto

Maranhense de Estudos Socioeconômicos e Cartográficos, 2020).

Such characteristics enable diverse economic activities, in addition to tourism in Barreirinhas.

Agriculture is practiced itinerantly, focused on subsistence, being one of the main economic activities of

the municipality. In addition, there is fishing, plant extraction, and extensive livestock farming.

The other municipality analyzed in this work is located on the Eastern Coast of Brazil, in the state of

Bahia, and due to this factor has some aspects that are different from Maranhão. Due to the greater energy

of the waves and greater intensity of upwelling, in this part of Brazil, which presents a more active

dynamic, the coastal behavior favors erosion and the formation of cliffs and reefs (Tessler & Goya, 2011).

These geomorphological contrasts, in addition to the different climatic and hydrographic conditions,

characterize the coasts of Maranhão and Bahia with particularities that influence not only their landscape

and the formation of the coastal ecosystems that compose them, but also their environmental and

socioeconomic dynamics.

For comparative analysis in this study, the municipality of Valença is located in the state of Bahia. It

has a population of 85 655 inhabitants, and has a territorial area of 1 123 975km² (IBGE, 2022b). Located

in the Lower South region of the state, this municipality has singularities in its coastal formation,

characterized by its rich biodiversity and proximity to significant ecological areas, including ample

mangrove environments bordered by salt flats, and sedimentary marine deposits forming extensive coastal

spits.

Such coastal formations, economic activities and ways of life are made possible by the climatic

conditions in the region, with predominance of the super-humid tropical climate type (Köppen & Geiger,

1948), but without a defined dry season, unlike Barreirinhas, with the average temperature of the hottest

month exceeding 18°C. The total rainfall of the driest month is above 60mm, with higher rainfall from

March to August, exceeding the total of 2 000mm per year. In the warmer months (December to February)

the average temperature is 24 to 25°C, easily exceeding 30°C in the summer (IBGE, 2002).

As for the hydrographic network present in Valença, the municipality is bordered to the south by the

Engenho river and to the north by the Jiquiriçá river, belonging to the Recôncavo Sul hydrographic basin,

located in the Central East region of the State of Bahia, which occupies an area of 6 900km², distributed

over 25 municipalities. The large mountains to the west of the municipal territory feed a considerable

number of springs, which form the main river channels present in the municipality. Among them, the Una

and Piaú rivers are the most important (Bahia, 2015). Valença is also bordered to the west by the Taperoá

channel fluviomarine system, with an expressive formation of estuarine environments.

Located in the Lower South region of the state, this municipality presents unique features in its

coastal formation, characterized by its rich biodiversity and proximity to important ecological areas,

including extensive mangrove forests bordered by salt flats, as well as marine sedimentary deposits that

form broad coastal sandbars. Its economic activities are distributed among agriculture, tourism, fishing, and

mariculture, supporting a wide network of family-based production.

However, informality in labor relations and in the supply of goods and services permeates the main

economic drivers of Valença, which have significant relevance in the regional economy of Bahia and

Brazil. In economic terms, the Gross Domestic Product (GDP) is led by the service sector (R$750 509.94),

followed by public administration, defense, education, public health, and social security (R$380 048.98),

while agriculture (R$133 284.54) and industry (R$129 033.74) play a secondary, but relevant, role in the

local economy (IBGE, 2020). These data reflect a context of informality in productive spaces, which may

be closely associated with economic and, consequently, social and cultural devaluation (Sheikh, 2019),

differing from the scenario of greater formalization of tourism activities observed in Barreirinhas,

Maranhão. Unlike Barreirinhas, whose economy is more focused on the primary sector, with activities of

extraction of natural resources and agriculture, in Valença, in addition to the relevance of these activities,

the industrial sector is also considerable.

In shrimp farming, one of the industrial activities present in Valença, the municipality stands out as

the largest shrimp producer in Bahia and the tenth in Brazil, and also occupies the ninth position in the

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production and processing of rubber, with a predominance of extractive activities with low implemented

technology (IBGE, 2022b).

Such physical, economic and social characteristics give the municipalities analyzed different forms

of occupation of their territories, hence different forms of appropriation of natural environments, whether

legally protected or not. Such understanding of socio-spatial differentiation is essential in the comparative

analysis of the legal evolution and land use occupation over the decades, proposed in this work.

2.2.

Methodological procedures

This study was developed in four operational stages: (I) theoretical foundation in bases with research

on the theme, analysis and choice of legislation to be compared and selection of the most effective mapping

methodologies for the proposed objectives; (II) preparation of cartographies of PPAs in accordance with

the selected legislation; (III) organization of cartographic data on Land Use and Occupation for the two

proposed municipalities; (IV) stage of comparative analysis of PPAs in each of the legislations and of the

spatial dynamics of the types of land uses adopted within these areas, for the two municipalities.

The thematic map of PPAs of the municipalities of Barreirinhas-MA and Valença-BA were

produced based on Law 7.511 of July 7, 1986, which amends provisions of Law 4.771 of September 15,

1965. We also produced the PPAs map referring to what is recommended by the new Forest Code (Federal

Law 12.651/2012). Thus, we prepared a map based on the previous code (Laws 4.771/1965 and

7.511/1986) and other map based on the current code for both areas of study.

As a reference, a guiding framework was developed for each municipality studied to compare the

diversity of types of PPAs identified, according to the forest codes mentioned (table I).

The production of two maps of PPAs has a comparative purpose to identify which of the forest laws

in terms of area provides greater protection of water resources and biodiversity (flora and fauna) in the

municipalities. It should be noted that Law 4.771/1965 has undergone changes and received additions over

time, one of which was instituted by Law 7.511 of July 7, 1986, which changed the width of PPAs for the

marginal strips of watercourses.

However, there was a new amendment based on Law 7.803 of July 18, 1989. In it, new PPAs

distances were established.

In the stage of determining the PPAs, there was delimitation of the water bodies of the

municipalities. To this end, there was acquisition of orbital images of the Landsat-5 satellites, Thematic

Mapper (TM) sensor with orbits/point: 219/62 and 220/62 with a passage date of Jul 10, 1990 for

Barreirinhas and Oct 23, 1990 referring to Valença, and the Landsat-8 images, Operational Land Imager

(OLI) sensor, orbits/points: 220/62 and 220/63, dated 07/18/2023 and 07/11/2023, respectively, for

Barreirinhas, and orbits/points: 216/069 and 070, dated 08/20/2023 for Valença.

The use of land use and land cover data from the Landsat satellite, referring to the year 1990, is

methodologically justified by the objective of analyzing environmental conditions within the legal

framework prior to the enactment of Law 12.651/2012. Images from other satellites, such as Sentinel,

although more suitable for detailed analyses in PPAs due to their higher spatial resolution, are only

available from 2016 onwards, a period already covered by the current Brazilian Forest Code.

Therefore, their use would not be consistent with the temporal scope necessary to assess land use

patterns associated with the previous legislation. Given the absence of higher-resolution orbital images for

earlier periods, the cartographic scale was standardized to 30 meters, compatible with the Landsat data,

which proved sufficient for the proposed comparative analysis. Thus, the approach adopted ensures

methodological and temporal coherence, aligning data availability with the legal context under

investigation.

After obtaining the images, they were imported into QGIS v.3.8.23 with reprojection of the data and

mosaic in color composition of type 5(R), 4(G), 3(B) for Landsat-5 and 4(R), 8(G), 3(B) for Sentinel-2A.

Then, a polygon vector layer was created, which enabled the delimitation of the water bodies of the study

areas for the years 1990 and 2023. Soon after the mentioned procedures, the tributaries were separated with

the break features tool, and, to determine the width of the channels, the line measurement tool was used,

then the buffer of the river channels was created. For this purpose, the Fixed Distance Geoprocessing >

Buffer algorithm was used. The distances were established, according to article 2 of Law 7.511 for water

bodies mapped in 1990 and article 4 of Law 12.651 for courses delimited in 2023. For the PPAs of all

channels, the following algorithms were applied: merge vector layers, dissolve and difference. The latter

was aimed at eliminating the filling of the buffer that would correspond to the river channels. It is noted

that the springs of the courses were covered in the application of the buffer

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Table I – Legal comparison of the types of PPAs in the coastal municipalities analyzed.

Quadro I – Comparação jurídica dos tipos de PPAs nos municípios costeiros analisados.

Municipalities

Law 7.511, of July 7, 1986

(Previous Law)

Law. 12.651, of May 25, 2012

(Current Law)

PPAs

Barreirinhas Valença

Art. 2 – The following are considered as subject to

permanent preservation, by the sole effect of this Law:

forests and other forms of natural vegetation located: 1.

within 30m for rivers less than 10m wide; 2. within

50m for watercourses that are 10 to 50m wide; 3. within

Art. 4. I – The marginal strips of any perennial and

intermittent natural watercourse, excluding

ephemeral ones, from the edge of the regular bed

channel, in a minimum width of: a) 30m, for

watercourses less than 10m wide; b) 50m, for

watercourses that are 10 to 50m wide; c) 100 m,

for watercourses that are 50 to 200m wide; d)

200m, for watercourses that are 200 to 600m wide;

e) 500m, for watercourses that are greater than

600m wide.

River Channels 100m for watercourses that measure between 50 and

100m wide; 4. within 150m for watercourses that are

between 100 and 200m wide; within a distance equal to

the distance between the banks for watercourses that are

Yes

more than 200m wide;

5

–

within 500m for

watercourses that are more than 600m wide.

Art. 4. IV – the areas around the springs and

Art. 2. c) in the springs, even in the so-called "water perennial water springs, whatever their

Springs

Dunes

Yes

eyes," whatever their topographic situation.

topographical situation, within a minimum radius

of 50m.

There is no specificity. Art. 2 The following are considered as subject to permanent preservation, by the sole

effect of this Law: forests and other forms of natural vegetation located: in the restingas, as dune fixers or

mangrove stabilizers. (Dunes without vegetation cover would not be protected in any legislation).

Yes

No

Restinga in

dunes

Art. 4. VI – restingas, as dune fixers or mangrove

stabilizers; Art. 3. For the purposes of this Law,

the following are defined as: XVI – restinga: sandy

Art. 2. f) in restingas, as dune fixers or mangrove

deposit parallel to the coastline, in a generally

stabilizers. (There is no conceptualization).

elongated form, produced by sedimentation

There is no specificity for areas with no dunes, only

processes, where different communities that

sandspits. It acts for the municipality of Barreirinhas-

receive marine influence are found, with mosaic

MA, but there is no influence for the municipality of

vegetation cover, found on beaches, sandspits,

Valença-BA

Restinga in

sandspits

No

Yes

dunes and depressions, presenting, according to the

successional stage, herbaceous, shrub and arboreal

stratum, the latter more interiorized.

Mangroves

There is no specificity.

Art. 4. VII – mangroves, in all their extension.

Yes

Art. 4. II – the areas surrounding the natural lakes

and lagoons, in strip with a minimum width of:

a) 100m, in rural areas, except for the body of

water with up to 20ha of surface, whose marginal

strip will be 50m;

Surroundings

of natural lakes Art. 2. b) around lagoons, lakes or natural or artificial

and lagoons

water reservoirs.

b) 30m, in urban areas.

Art. 4. V – slopes or parts thereof with a declivity greater than 45°, equivalent to 100% on the line of greatest

slope.

Declivity

No

Yes

Source: Authors

In order to identify the other PPAs of the municipalities and illegal use and occupation of these

areas, we used land use and cover data for 1990 and 2022 from MapBiomas collection 9 (table II). The

classes proposed by MapBiomas were grouped according to the characteristics that were most effective for

the objectives of the study. This collaborative project produces an annual mapping of land cover and use

with data starting from 1985 (MapBiomas Brasil, 2023).

The MapBiomas raster land use and cover data obtained from the website through the Google Earth

Engine platform were converted into QGIS for the vector structure, then the vector for the year 1990 was

clipped with the drainage PPAs as a mask layer, based on Law 7.511/1986, while for 2022 the same was

done, however, based on the PPAs obtained based on Law 12.651/2012. The land covers (table I), in turn,

established as PPAs were represented on the maps as determined by the laws analyzed.

Finally, the types of use and occupation included in the PPAs were considered in order to identify

the quantity of area and their type of change in the dynamics of use in the context of each legality system of

the Forest Codes. By identifying these characteristics, it is possible to understand which type of use

underwent expansion or reduction in relation to legal change in recent decades. To identify the PPAs

associated with slopes, we used the Digital Elevation Model (DEM) of the Brazilian Geomorphometric

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Soares, I. G., Sampaio, S. A., Oliveira, R. C. Finisterra, LXI(131), 2026, e41854

Database (TOPODATA) of the National Institute for Space Research (Instituto Nacional de Pesquisas

Espaciais, 2011), with a spatial resolution of 30 meters. These data correspond to the sheets: 02S435_ZN

and 03S435_ZN for Barreirinhas and 13S405_ZN and 13S39 for Valença. The scenes were downloaded

from the TOPODATA website and then imported into QGIS.

Table II – Characterization of land use and land cover classes (MapBiomas level 4) in Valença and Barreirinhas (1990 e

2022).

Quadro II – Caracterização das classes de uso e ocupação do solo (MapBiomas nível 4) em Valença e Barreirinhas (1990 e

2022).

Legality of use

(PPA)

Class

Description

Forest

Types of vegetation with a predominance of tree species, with continuous canopy

formation (Riparian Forest, Gallery Forest, Dry Forest and Cerradão [Ribeiro & Walter,

2008]), in addition to semideciduous seasonal forests.

Savannas with defined tree and shrub-herbaceous strata (Restricted Sense Cerrado:

dense Cerrado, typical Cerrado, sparse Cerrado and rocky outcrop Cerrado).

Savanna

Forest Formation

Grasslands with a predominance of herbaceous stratum (dirty field, clean field and

rocky outcrop field) and some areas of savanna such as the rocky outcrop Cerrado.

Grassland

Tree Restinga

Mangrove

Forests established on sandy soils or dunes in the coastal zone.

Dense, evergreen forests, often flooded by the tide and associated with the coastal

ecosystem of Mangrove.

Mangrove

ADEQUATE

Salt flats or leached soils are formations mostly devoid of arboreal vegetation, being

associated with a higher, hypersaline and less flooded zone of the mangrove, in general,

in the transition between mangrove and mainland.

Salt flat

Vegetation with predominance of herbaceous stratum subject to seasonal flooding (e.g.,

Wet Field) or under fluvial/lake influence (e.g., Swamp). In some regions, the

herbaceous matrix occurs in association with arboreal species of savanna formation

(e.g., Parque de Cerrado) or palm trees (Vereda, Palmeiral).

Flooded Field

and Wetland

Area

Non-Forest

Natural Areas

Beach, Dune

and Sandy

Beach

Sandspits, bright white in color, with no predominance of vegetation of any kind.

Herbaceous vegetation with fluviomarine influence.

Herbaceous

Restinga

Dominant vegetation type of pioneer areas (restinga), occurring in the dunes and

dominated by nanophanerophytic communities.

Shrub Restinga

Continental

Waters

Continental

Waters

Rivers, lakes, dams, reservoirs and other bodies of water.

Urbanized Area

Urbanized Area Areas with significant density of buildings and roads.

Area referring to artificial lakes, with predominance of economic activities of fish,

seafood or crustacean farming.

Aquaculture

Mining

Areas referring to industrial or artisanal mineral extraction (mining), with clear soil

exposure by anthropic action.

Bare soil

Other areas

with no

vegetation

Areas with non-permeable surfaces (infrastructure, urban expansion or mining) not

mapped in their classes and regions of bare soil in natural areas or in off-season crop

areas.

Areas occupied with short- or medium-term agricultural crops, usually with a vegetative

cycle of less than one year, which after harvest require new planting to produce;

Forestry: Tree species planted for commercial purposes. Pasture; mixed use areas where

it was not possible to distinguish between pasture and agriculture, areas with non-

permeable surfaces (infrastructure, urban expansion or mining).

INADEQUAT

E/

UNDER

LEGAL

PERMISSION

Agriculture

Soy

Areas cultivated with soybean crop.

Predominantly planted pasture areas, directly associated with agricultural activity.

Natural pasture areas, in turn, are predominantly characterized as grassland or wetlands,

and may or may not be subjected to grazing practices.

Agriculture

Forestry

Pasture

Other

Temporary

Crops

Areas occupied with short- or medium-term agricultural crops, usually with a vegetative

cycle of less than one year, which after harvest require new planting to produce.

Agricultural use areas where it was not possible to distinguish between pasture and

agriculture.

Mosaic of uses

Forestry

Tree species planted for commercial purposes (e.g., pine, eucalyptus, araucaria).

Source: Authors

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In the Geographic Information System (GIS), data were processed, namely: mosaic of the DEM;

reprojection; correction of negative values by applying a formula in the raster calculator of the System for

Automated Geoscientific Analyses (SAGA GIS); pixel filling without data based on the Fill without Data

tool; removal of spurious (closed) depressions of the DEM through the Fill Sinks (Wang & Liu, 2006)

algorithm in SAGA GIS; clipping. Finally, we applied the declivity algorithm expressed in degrees.

3.

RESULTS AND DISCUSSION

When studying the types of land use and land cover in the two municipalities analyzed, in the

reference timeframes, we found a significant increase in the agricultural classes of mechanized use,

especially in Barreirinhas, with the implementation of soybean cultivation.

In 1990, Agriculture occupied 91.62km² of the municipality, while in 2022 it started to occupy an

area of 159.74km², that is, an increase of 74.34%; in contrast, Forest Areas were reduced approximately by

3.81% and Non-Forest Natural Areas had a loss of 0.43% in 2022 (fig. 2 and 3).

Fig. 2 – Land use and land cover scenarios in the municipalities of Barreirinhas and Valença organized according to

MapBiomas data (1990 and 2022).

Fig. 2 – Cenários de uso e ocupação do solo nos municípios de Barreirinhas e Valença, organizados de acordo com os

dados do MapBiomas (1990 e 2022).

Source: MapBiomas (1990,2022)

The mangrove area also underwent a 2.5% reduction between 1990 and 2022, however, this change

in cover is associated with natural dynamics identified in the advance of mobile dunes over this feature. In

this sense, the dune area had an increase of 2.3% in 2022, with the wind action being the main factor

responsible for the change. In 1990, the bare soil formed only by Other Areas with no Vegetation increased

by about 2.3% in 2022, this change was due to the introduction of mining, which contributed to the growth

in terms of occupied area.

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For the same reference period, there was an increase in the Urbanized Area, which in 1990 had an

area of 5.1km², while in 2022 it started to have 14km², that is, a growth of 172.8% in the last 32 years. This

is mainly due to the tertiary sector of Barreirinhas, which underwent an advance due to tourism in the

Lençóis Maranhenses region. This tourism has contributed to the entry of capital into the municipality and

creation of employment and income for the local population. The activity of this economy sector ranges

from the handicrafts practiced by residents of the city and villages, sale of meals in restaurants, lodging in

inns and hotels, rental of quadricycles, and transport of tourists to Lençóis Maranhenses, among others.

Fig. 3 – Surface area of the land use and land cover classes present in the analysed coastal municipalities (1990 and 2022).

Fig. 3 – Superfície das classes de uso e ocupação do solo existentes nos municípios costeiros analisados (1990 e 2022).

Source: Mapbiomas (1990, 2022)

The GDP of Barreirinhas in 2021 was R$635 796 million, according to IBGE municipal GDP data

(2022a). The primary sector of the economy characterized by extensive agricultural activities, fishing,

mining and plant extraction has a substantial importance in obtaining income in Barreirinhas.

However, the advance of agriculture in Barreirinhas and the consequent loss of native vegetation in

recent decades is a negative aspect of this activity, as it is associated with deforestation and fires in the

region. Pasture is the land use associated with the growth of municipal agriculture; in 1990, it occupied an

area of 5.5km², while in 2022 it represented about 63.8km², which implies an exacerbated increase of

1 056%.

In Valença, the dynamics of evolution of land use and occupation is, to some extent, similar to that

of Barreirinhas. There was a significant decrease in forested environments (with a 14% reduction in

covered area) and in mangroves (with an almost 11% reduction in area), with growth of environments for

agricultural activities and urban areas (whose classes doubled the cover area in three decades) (fig. 3).

Other economic activity that showed significant growth is Aquaculture (with more than 120%

increase in covered area). Aquaculture activities involve producing fish (fish, molluscs, algae, shrimp and

others) in captivity.

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According to Municipal Livestock Production data (IBGE, 2023b), in 2023, the municipality of

Valença rose as the 10th largest shrimp producer in Brazil (with more than 2 650 tons produced). The

central problem of captive fish farming is the transformation of natural ecosystems, such as mangroves and

salt flats, into shrimp ponds, causing the destruction of habitats that are essential for the reproduction of

marine species, in addition to causing the reduction of biodiversity in the region.

In addition, for the development of industrial activity, there is adoption of intensive use of

chemicals, such as pesticides and antibiotics, thus contaminating the water (García et al., 2019). And,

among the social impacts, the expansion of aquaculture activities is associated in Valença with the loss of

traditional fishing territories. In order to trace the level of protection of PPAs and which land uses are

directly associated with this evolution, we carried out a comparative cartographic analysis of the size of the

protected areas provided for in the two environmental legislations.

According to the legal analysis applied to the cartographies, the PPAs covered by Laws 4.771/1965

and 7.511/1986 (previous Law) occupied an area of 677.5km² in Barreirinhas and in Law 12.651/2012

(current Law) this value becomes 649.6km², which means a reduction of 4% of the areas protected by the

Forest Code (table III).

Table III – Area of the PPAs delineated in environmental legislation in 1990 and 2022 for the analysed municipalities.

Quadro III – Área das APP delimitadas na legislação ambiental de 1990 e 2022 para os municípios analisados.

Permanent

Preservation

Areas

Barreirinhas-MA

Valença-BA

Area in km² in 1990

Area in km² in 2022

River channels

and springs

channels with a width of 30

and 100m: 160.98km²

channels with a width of 30

and 100m: 160.98km²

287.53

Not applicable

390.05

225.49

Not applicable

374.4

Dunes

Not applicable

Restinga in

dunes

Restinga in

sandspits

There is no specificity in the

current law

Not applicable

48.47

37.13

25.75

There is no specificity in the

previous law

There is no specificity in the

current law

Mangroves

Surroundings of

natural lakes and

lagoons

There is no specificity in the

previous law

There is no specificity in the

current law

1.32

4.65

Declivity

Not applicable

649.68

0.13

TOTAL

677.58

161.11

228.64

Source: Authors

This is mainly due to the reduced protection of River Channel and spring areas, and the reduced

resting vegetation cover in dunes due to anthropogenic alteration. This leads to considerable environmental

consequences due to the destruction of these ecosystems.

In Valença, there was an increase in the cover of PPAs, which represented 161.1km² and expanded

to an area of 228.6km², which represents an increase of 42% of the total area previously protected.

Considering that restinga environments in sandspits, mangroves and around natural lakes and lagoons had

no legal restrictions in 1990 and started to have them from 2012, this increase is justified (table III).

However, not only was the environmental legislation changed, but the types of land use and

occupation in these two municipalities compared also underwent significant changes, including the cover

within the PPAs, focal areas of analysis in this present study.

Figures 4 and 5 show the spatialization of this change, considering the contexts of legal inadequacy

of land use in the PPAs of the municipalities under analysis between 1990 (considering Law 4.771/1965)

and 2022 (according to the new Forest Code), and table IV shows the sizes of areas and types of uses

assumed by the old PPAs.

Regarding the inadequate uses in the PPAs in Barreirinhas, the results indicate that 9% of them were

occupied by Agriculture (pasture and mosaic of uses), the Urbanized Area class (0.7km²) and Bare Soil

(0.2km²), in turn, they were also associated with a conflict in relation to environmental legislation. They

involved 0.3% of the PPAs. These results show that 27.7km² (approximately 10%) of the banks of the

municipality’s hydrographic network were occupied irregularly, as determined by the mentioned forest

code (table IV).

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Fig. 4 – Legal inadequacy of land use in the PPAs of the municipality of Barreirinhas between 1990 and 2022.

Fig. 4 – Inadequação legal do uso do solo nas APP do município de Barreirinhas entre 1990 e 2022

Source: MapBiomas (1990; 2022); USGS (1990; 2022); ZEE-MA (2021); IBGE (2022)

Table IV – Comparison with the size of areas and types of uses assumed by the old PPAs.

Quadro IV – Comparação com a dimensão das áreas e os tipos de uso assumidos pelas antigas APPs.

Permanent Preservation Areas (km²)

Barreirinhas, Maranhão

Valença, Bahia

Law 4.771, of September

15, 1965 and Law 7.511,

of July 7, 1986

Land Use and Cover

Law 4.771, of September

15, 1965 and Law 7.511,

of July 7, 1986

Law 12.651, of May 25,

2012

Law 12.651, of May 25,

2012

(Current Law)

(Previous Law)

Inadequate Use

(Aquaculture, Bare Soil,

Agriculture and livestock

and Urbanized Area)

27.71

30.31

38.92

55.38

Forest

191.85

34.94

—

138.19

28.27

105.82

1.61

—

112.0

17.99

25.54

Non-Forest Natural

Formation

Mangrove

27.58

Source: Authors

The vegetation cover that involves the Forest, Non-Forest Natural Formation and Mangrove classes

concentrate 86% of the drainage PPAs for the year 1990, while to the north of the municipality, specifically

in the Preguiças River, mobile dunes (8.4km²) occupy 2.9% of the banks and 0.6% (1.7km²) are small areas

of water bodies.

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In 2022, the conflict situation is aggravated by agricultural activity, totalling 12.8% of inadequate use in the

protection areas, while the Urbanized Area (just over 1km²) and Bare Soil (0.14km²) total 30.3km² (13.3%

of the occupation of the PPAs). While the plant species grouped in the Forest, Non-Forest Natural

Formation and Mangrove occupy about 82.5% of the banks protected by law, while mobile dunes (6.8km²)

3% and water bodies (2.4km²) only 1%.

Fig. 5 – Legal inadequacy of land use in the PPAs of the municipality of Valença between 1990 and 2022.

Fig. 5 – Inadequação legal do uso do solo nas APP do município de Valença entre 1990 e 2022.

Source: MapBiomas (1990; 2022); USGS (1990; 2022); IBGE (2022)

In the current legislation, the protection associated with water bodies was unfavorable compared to

the previous law; the results for the GIS mapping show that the loss of PPAs was approximately 21%.

Considering all the PPAs in Barreirinhas, the situation of greater protection of vegetation is identified in the

previous law, as the new forest code for this application scenario presents a decrease of 4%.

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In the municipality of Valença, although the PPAs had their cover expanded with the updated Forest

Code, the inadequate land uses and occupation within these areas were also expanded. As an example, the

activities of Aquaculture, Agriculture, Urbanized Areas and Bare Soil, which occupied approximately

39km², started to occupy 55.3km² within the PPAs in this municipality. This indicates a lack of robust

inspection in the PPAs, which, in turn, can lead to serious environmental damage, such as illegal

deforestation, the release of pollutants into water bodies and the irregular occupation of protected areas.

This occurs, for example, when landowners invade or use in an inadequate manner these areas for activities

such as agriculture and livestock farming, or illegal construction.

Although the previous Forest Code has a protective character, there are flaws associated with the

absence of a more specific and clear delimitation of PPAs. This same conclusion was noted by Santos Filho

et al. (2015) in relation to the first Brazilian forest code of 1934. In addition to methods for inspecting

PPAs more efficiently. According to Santos Filho et al. (2015, p. 279):

Over the decades after 1930, the Forest Code underwent several changes until the

introduction of the new Code in 1965, and, among the changes in relation to the revoked

Code of 1934, it is worth mentioning the creation of the Legal Reserve and Permanent

Preservation Areas.

The 2012 Forest Code has greater clarity regarding the delimitation of PPAs compared to the

previous one, with this difference being the main aspect responsible for the current law providing greater

protection of vegetation cover; however, in relation to the protection of vegetation on the banks of

watercourses, Law 7.511/1986 is more favourable toward preservation. This change occurs in what is

determined in article 2, paragraph "a" and item 4 of said law: "within 150m for watercourses that are

between 100 and 200m wide; within a distance equal to the distance between the banks for watercourses

that are more than 200m wide". This is consistent with Zanatta et al. (2014, p. 205), who noted that the

Forest Code update represented a setback in the preservation of water bodies, since "it does not meet the

vegetation efficiency ranges necessary for the conservation of water resources, significantly reducing the

functions and, consequently, the services provided by nature to man".

The Brazilian Forest Code was created at the beginning of Brazil’s industrialization process in the

1930s, aiming to standardize the use of raw material from forests. This objective is fundamental, as it is

necessary to establish rules for the use of forest resources. However, what is found in the study area is non-

compliance with what is prescribed by law until the present moment. The growth of agriculture in

Barreirinhas and Valença, for example, was followed by increased pressure on water resources, soil and

consequently forest biodiversity.

PPAs are intended to protect environmentally vulnerable sites, such as riverbanks, hilltops and

slopes, which should not be deforested so as not to cause erosion, river silting and mass movements, in

addition to protecting springs, fauna, flora and biodiversity, etc. Thus, the lack of native vegetation cover in

PPAs cause erosive processes with greater intensity and "triggers the loss of surface layers of soils, with

consequent loss of fertility, transforming areas with major potential for food production or preservation into

degraded sites with low agricultural productivity" (Bonzanini & Lupinacci, 2023, p. 24).

While, in Valença, in addition to the problems in drainage PPAs that are similar to what occurs in

Barreirinhas, the economic activities of aquaculture also gradually appropriate the areas of mangroves and

salt flats. That is, the theory is not in line with the practice in relation to the areas that should mandatorilly

be protected.

With a focus on the physiognomy of salt flats, part of the mangrove ecosystem, as well as the saline

areas, are not covered by the previous law or by the current law, as a PPAs:

Salt flats [Apicuns] are flat areas with high salinity, devoid of vegetation or with sparse

vegetation, located in the innermost portion of the mangroves, especially between

mangroves and slopes, at the mid-supralitoral interface. Its vegetation is composed of

herbaceous plants that grow in the sand. (Hadlich et al., 2016, p. 69)

The definition itself shows the relation between them; both the mangrove and the salt flat are formed

by the interaction of tidal dynamics, developing vegetation with capacity to adapt to brackish environments

with high salinity.

The Federal Law in force, in its article 4, determines as PPAs in paragraph VII "mangroves, in all

their extension." Thus, item seven leads to the understanding that the entire ecosystem is being legally

protected; however, this law dissociates the treatment for salt flats and saline areas. Thus, there is a

protection of some features rather than others that are not considered as PPAs, although they all are part of

the same system (Albuquerque et al., 2015).

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Salt flats are covered by the new Forest Code in chapter III-A, entitled: "Ecologically Sustainable

Use of Salt Flats and Saline Areas", and this chapter was added by Provisional Measure 571, of May 25,

2012, later converted into Law 12.727, of Oct 17, 2012. Paragraph 1 clarifies that salt flats and saline areas

can be used in shrimp farming and saline activities.

It is understood that not considering salt flats and saline areas as part of the mangrove system and the

possibility of their use for the aforementioned activities constitute an obstacle to the very protection of the

mangrove, as both physiognomies are part of the same ecosystem. In this sense, Albuquerque et al. (2015,

p. 129) ratify that “although mangroves and their correlated and interdependent features are characterized

by intense dynamics and close interrelation, the current Brazilian environmental legislation at the federal

level does not seem to understand or disregard the relevance of such characteristics”. This exclusion would

necessarily result in the violation of PPAs because they are connected areas, which makes it difficult for

environmental agencies to inspect them.

Another important element in studies related to the application of the forest code concerns riparian

vegetation, which corresponds to plant formations near water bodies, thus addressing the concept of

distance and also water (Kobiyama, 2003). In these works, the terms riparian zone and riparian ecosystem

are common. The first refers to a three-dimensional physical space that includes vegetation (tree, grass,

etc.), soil and river (body of water). "Its extension is horizontally up to the reach of the flood and vertically

from the regolith (below) to the top of the forest canopy (above)" (Kobiyama, 2003, p. 5). While the second

term should be used when referring to the system, processes, mechanisms, among others; it is appropriate

to use the term riparian ecosystem, which is an open system. "Therefore, it is considered an ecotone

between terrestrial and aquatic ecosystems through the movement of surface water and groundwater"

(Kobiyama, 2003, p. 6).

Riparian vegetation has several functions, namely: stabilization of slants and slopes, maintenance of

river morphology and protection from flooding, retention of sediments and nutrients, mitigation of water

and soil temperature, provision of food and habitat for aquatic species, maintenance of ecological corridors,

landscape and recreation, fixation of carbon dioxide, interception of rocky debris (Silva, 2003).

In this context, Silva (2003) presented a list of recommended widths for riparian strips according to

the functions performed. Such widths are the same as those presented in Connecticut River Joint

Commissions (CRJC, 1998). Thus, the ideal widths for riparian zone functions are 10 to 15 meters for slant

stability, 15 to 30 meters (fish habitat), +30 meters (nutrient removal), 30 to 45 meters (sediment control),

+60 meters (flood control), +90 meters (wildlife habitat).

As clarified by Zanatta et al. (2014, p. 206): "According to the studies of CRJC (1998) and the

survey carried out by Silva (2003), more than 180m (90+m on each bank) of PPA are necessary in order to

effectively protect water bodies, soil and biodiversity".

Based on the riparian zone’s systemic characteristics and important functions, it is proposed that the

PPAs of watercourses, lagoons and lakes consider the riparian zone for their delimitation, since considering

only the width of a water body to define the areas to be protected and not the dynamics, exchange of matter

and energy, interactions between landscape components, in addition to the natural function of the systems,

is detrimental to the very environmental sustainability goal of the legislation. Accordingly, it is also

suggested the inclusion of salt flats and saline areas as PPAs associated with the mangrove ecosystem or,

alternatively, the reduction of the areas available for use by these economic activities.

Another significantly studied issue – derived from the same sense of ecosystem protection and not

from the functioning and dynamics of the environments, questioned by Brazilian researchers, since before

the new Forest Code – is the exclusion of mobile dunes as PPAs. As only the restinga ecosystems, which

fix the dunes, are considered, only the fixed dunes end up being protected. While dune environments,

without floristic cover, become targets for urban expansion, implementation of large eolian projects, among

other related issues, derived directly from this loophole in environmental legislation.

In article 2 and item VIII of CONAMA Resolution 303, of March 20, 2002, dunes are defined as "a

geomorphological unit with predominantly sandy constitution, with the appearance of a comorum or hill,

produced by the action of winds, located on the coast or inside the continent, which may or may not be

covered by vegetation". Thus, in Barreirinhas there are mobile and fixed dunes.

Coastal dunes provide habitats for plants, animals and microorganisms, help protect beaches, coasts

and interior areas from various disturbances, such as extreme weather conditions, storms and sea level rise;

in addition, dunes and beaches provide ecosystem services, such as coastal protection, acting as natural

barriers against storms, minimizing damage caused by erosive processes and flooding (Lustig, 2023; Silva

et al., 2024).

When dunes are removed or replaced with anthropogenic activities in low-altitude areas,

“environments become more susceptible to flooding processes during storms, triggering damage to

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infrastructure, economic losses in seaside developments, and potentially affecting other ecosystem

services.” (Silva et al., 2024, p. 2).

Given the ecological importance of dunes (fixed and mobile) and because they are areas with

remarkable scenic beauty, high complexity and natural vulnerability resulting from deflation processes, it is

also suggested their inclusion as PPAs in the current forest code; it should be noted that CONAMA

resolution 303/2002 in article 3 and item V establishes dunes as PPAs.

4.

CONCLUSIONS

The findings of this study indicate that environmental conditions afford different types of ecosystem

formation in the coastal zone of Northeast Brazil. Comparing both municipalities, one located on the

Eastern Coast and the other on the Northern Coast of the Brazilian territory, it is understood that the legal

applications of environmental protection also differ from each other. These municipalities have major

international tourist relevance due to the proximity to Lençóis Maranhenses and Morro de São Paulo,

which represent icons of Brazilian tourism; however, their inefficient legal protection jeopardizes not only

the ecological integrity, but the very sustainability of tourism activities in the medium and long term. The

inadequate appropriation of the soil, given the economic and environmental potential of these territories,

shows a contradiction between tourism development and environmental conservation, urgently requiring:

the harmonization of PPA legislation with coastal geomorphological particularities; and integrated

management mechanisms that make ecosystem protection compatible with sustainable economic activities.

In short, in the municipality of Barreirinhas, located in the state of Maranhão, the update of

legislation focusing on PPAs indicated a loss of legally protected areas. Such areas were quickly altered,

occupied by expansion of urbanized areas, bare soil and agricultural activities, to the detriment of forests,

especially in environments close to the banks of rivers and in dune environments.

In the analysis of the municipality of Valença, in the state of Bahia, considering the different existing

ecosystems, the same update of the legislation focusing on PPAs indicated an increase in legally protected

areas. With the addition of restinga ecosystems in sandspits, mangroves and around natural lakes and

lagoons, the new Forest Code now covers almost double the previously protected areas. However,

inappropriate uses within PPAs have also increased, such as the introduction of aquaculture, forestry, bare

soil, agriculture and urbanized areas.

Another research finding is that the delimitation of PPAs must follow the environments’

hydrological, ecological functioning behavior, dynamics and processes. The delimitation of PPAs only by

ecosystem characteristics excludes other ecological formations with high importance that do not have the

same classification regarding dominant type of vegetation. For example, the ecosystems included in the

fluviomarine plain: salt flats, leached soils and saline areas, which have a water and ecological dynamics

that is similar to that of mangroves. Due to this legal loophole, potentially polluting projects are installed in

unprotected ecosystems, in the center and edges of mangroves, such as shrimp farming and aquaculture,

which have shown significant growth in occupied area in the last three decades.

Similarly, there are insufficient legal concepts for protection of riparian zones and their important

functions, when it is proposed that the PPAs of watercourses, lagoons and lakes consider only the width of

water bodies to define the areas to be protected and not the dynamics, exchange of matter and energy,

interactions between landscape components, in addition to the natural function of the systems; thus,

disregarding these aspects is detrimental to the very environmental sustainability goal of the legislation.

ACKNOWLEDGEMENTS

We extend our gratitude for the financial support provided for the research carried out by Idevan Gusmão

Soares and Sarah Andrade Sampaio, funded by the Brazilian Federal Agency for Support and Evaluation of

Graduate Education (CAPES), under grant numbers 88887.675419/2022-00 and 88887.675413/2022-00,

respectively.

AUTHORS’ CONTRIBUTIONS

Idevan Gusmão Soares: Writing – original draft preparation, Data curation, Formal analysis, Visualization.

Sarah Andrade Sampaio: Writing – original draft preparation, Formal analysis, Visualization. Regina Célia de

Oliveira: Supervision, Writing – review and editing, Project administration.

16

Soares, I. G., Sampaio, S. A., Oliveira, R. C. Finisterra, LXI(131), 2026, e41854

ORCID

Idevan Gusmão Soares https://orcid.org/0000-0002-9604-2867

Sarah Andrade Sampaio https://orcid.org/0000-0002-1302-7064

Regina Célia De Oliveira https://orcid.org/0000-0002-3506-5723

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LEGAL DOCUMENTS

República Federativa do Brasil (2012). Lei nº 12.651/12, de 25 de maio de/05/ 2012. Dispõe sobre a proteção da vegetação

nativa; altera as Leis nºs 6.938, de 31 de agosto de 1981, 9.393, de 19 de dezembro de 1996, e 11.428, de 22 de

dezembro de 2006; revoga as Leis nº 4.771, de 15 de setembro de 1965, e 7.754, de 14 de abril de 1989, e a Medida

Provisória nº 2.166-67, de 24 de agosto de 2001; e dá outras providências [Law 12.,651/12, of May 25/05/, 2012.:

Provides for the protection of native vegetation; amends Laws 6,938 of August 31, 1981, 9,393 of December 19,

1996, and 11,428 of December 22, 2006; repeals Laws 4,771 of September 15, 1965, and 7,754 of April 14, 1989,

and Provisional Measure 2,166-67 of August 24, 2001; and makes other provisions].

https://www.planalto.gov.br/ccivil_03/_ato2011-2014/2012/lei/L12651compilado.htm

República Federativa do Brasil (2007). Resolução CONAMA nº 390/07, de 14/05/2007: Dispõe sobre a nova composição das

Câmaras Técnicas do Conselho Nacional do Meio Ambiente – CONAMA para o biênio 2007–2009, e dá outras

providências [CONAMA Resolution 390, of May 14, 2007: Establishes the new composition of the Technical

Chambers of the National Council for the Environment – CONAMA for the 2007–2009 biennium, and provides other

measures]. Diário Oficial da União.

República Federativa do Brasil (2002). Resolução CONAMA nº 307/02, de 05/07/2002: Estabelece diretrizes, critérios e

procedimentos para a gestão dos resíduos da construção civil [CONAMA Resolution 307, of July 5, 2002:

Establishes guidelines, criteria and procedures for the management of construction waste]. Diário Oficial da União.

República Federativa do Brasil (1997). Resolução CONAMA nº 237/97, de 19/12/1997: Dispõe sobre a revisão e

complementação dos procedimentos e critérios utilizados para o licenciamento ambiental [CONAMA Resolution

237, of December 19, 1997: Provides for the revision and supplementation of procedures and criteria used for

environmental licensing]. Diário Oficial da União, nº 247, seção 1, 30841–30843.

República Federativa do Brasil (1989). Lei nº 7.803/89, de 18/07/1989. Altera a redação da Lei nº 4.771, de 15 de setembro

de 1965, e revoga as Leis nºs 6.535, de 15 de junho de 1978, e 7.511, de 7 de julho de 1986 [Law 7.803/89, of July

18, 1989. Amends the wording of Law 4.771, of September 15, 1965, and repeals Laws 6,535, of June 15, 1978, and

7.511, of July 7, 1986]. https://www.planalto.gov.br/ccivil_03/Leis/L7803.htm

República Federativa do Brasil (1986). Lei nº 7.511/86, de 07/07/1986. Altera dispositivos da Lei nº 4.771, de 15 de

setembro de 1965, que institui o novo Código Florestal [Law 7.511/86, of July 7, 1986. Amends provisions of Law

4.771, of September 15, 1965, which establishes the new Forest Code].

https://www.planalto.gov.br/ccivil_03/LEIS/L7511.htm

República Federativa do Brasil (1965). Lei nº 4.771/65, de 15/09/1965. Institui o novo Código Florestal [Law 4.771/65, of

September 15/09/1965. Institutes the new Forest Code]. https://www.planalto.gov.br/ccivil_03/LEIS/L4771.htm

República Federativa do Brasil (1934). Decreto nº 23.793/34, de 23/01/1934. Aprova o Código Florestal [Decree 23.793/34,

of 23/01/1934. Approves the Forestry Code]. https://www2.camara.leg.br/legin/fed/decret/1930-1939/decreto-23793-

23-janeiro-1934-498279-publicacaooriginal-78167-pe.html

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