There is an ecosystem in the Amazon where the pressure of deforestation cannot prevail: the mangroves. 

A study carried out by the Federal University of Pará (UFPA), the Federal Rural University of the Amazon (Ufra) and the Vale Technological Institute (ITV) found that less than 1% of the mangroves in the Amazon region were impacted by human interventions such as urban expansion and the construction of roads.

A mangrove is no more than a transition area between water and dry land, forming humid and fertile lowlands and constantly flooded forests. 

The result of the equation is muddy soil with a high salt content. However, in mangroves there are plants adapted to such conditions, which explains the aerial roots. Furthermore, this ecosystem is home to fish and crustaceans.

Professor Sanae Hayashi, from the Geotechnology, Financial and Environmental Education Laboratory at UFRA, recalls that more than 70% of mangroves in Brazil are within the circumscriptions of  Amapá, Pará and Maranhão states. This area is equivalent to eleven times the size of the city of São Paulo (SP). 

Professor Hayashi highlights that mangroves play a significant role in the socioeconomic sustainability of riverside communities, in addition to providing extraction activities relevant for subsistence through the consumption of fish and crabs.

The study analyzed 7,820 square kilometers of mangroves via satellite using the RapidEye system, starting at the mouth of the Amazon River, near the Marajó Archipelago, as far as São Luís Island, where the capital of Maranhão is located. 

The 1% detected as an unconserved area corresponds to 66.85 square kilometers. The images cataloged between 2011 and 2015 were compared with older satellite images, which certified the state of preservation of the mangroves.

"Mangroves also provide protection for the coastline against catastrophic events, in addition to being shelter and refuge for animal species. They are productive areas in terms of primary production, with enormous carbon storage. This points to the region's differential status in the carbon credits market, which is on the rise when the world wants to reduce greenhouse gases in the atmosphere. Worldwide, mangrove loss rates are 1% to 2% per year. Our Amazonian mangroves are considered preserved, with the low demographic density of the region providing enormous contribution, if we compare it with the Northeast and Southeast regions of Brazil, for example. Furthermore, these areas increasingly gain legal support, with the creation of extractive reserves. Another contributing factor is that less than 10 % of the road network in the analyzed region is paved", says the researcher.

Researcher defends more conservation policies

Pedro Walfir de Souza Filho, a professor at the Institute of Geosciences at the Federal University of Pará (UFPA) and a researcher at the Instituto Tecnológico Vale (ITV), has been studying the Amazon mangroves for two decades. 

He says that the analysis covers the largest continuous extension of mangroves in the world, with a water level that reaches six meters and trees between 20 and 30 meters, creating large mud deposits in a macrotidal region. In other words, this natural robustness of the mangrove is, in itself, a significant inhibitor of human destructive action for economic activities.

“It's very expensive to cut down a mangrove. Machines and tractors don't fit there. They would get stuck in the mud. Furthermore, between 80% and 90% are located in conservation units, which limit the uses of this mangrove. In other parts of the world, such as In Southeast Asia and Ecuador, a large part of these mangroves is used to grow rice, oysters, fish and shrimp, resulting in mangroves suffering strong economic pressure, with agents replacing the native area with aquaculture tanks. It is a process that is also happening in the Brazilian Northeastern States”.

“There are two distinct ecosystems in the mangrove: one is the mangrove forest and the other is the apicum, which are hypersaline areas, very salty, which do not enable the development of vegetation”.

“Thus, it is this area that has been used for tanks, fish farming, crustaceans and even salt farming, the extraction of salt. In mangroves, less than 1% has been altered. But, in the apicuns, of the twelve kilometers that we mapped, 2% are in use and have already been altered. It is a concern that we need to have due to this economic activity that is profitable, but becomes a threat to this very important ecosystem”.

"The literature has registered significant changes in mangroves in countries such as India, Bangladesh and New Guinea. Therefore, we start from the hypothesis that the mangroves in the Amazon need a special policy so that they remain in this stage of conservation and that degradation is not allowed to advance as is occurring in other places in the world", he warns, highlighting that the Forest Code of Brazil, which came into force in 2012, allows the use of apicum, while mangroves are considered areas of permanent preservation"

AMAZONIANS

The municipality of Bragança, in the Northeast of Pará, concentrates a large part of the degradation sites mapped by the study. The reason is the construction of the PA-458 state highway, which cuts through the mangrove forest for 26 kilometers, says the researcher. On the other hand, Pedro considers that the road built between the 1970s and 1980s allowed researchers greater access to the region, generating more knowledge about the geochemistry, biodiversity and conservation of these ecosystems. Pedro understands that the good relationship between the Amazonians and the mangroves is also fundamental for the construction of these positive data regarding preservation.

"It's a population that preserves the mangroves and understands how to use them in a sustainable way. Amazonians know where there are big crabs, where there are small crabs and they respect the crabs' walking cycle... This data proves that they exploit them in a responsibly way, and not to the point of total depredation. The Amazonians always look for new rich areas while the previous extraction site recovers. I think Brazil and the world have a lot to learn from the way the Amazonians conserve their mangroves. In eastern Pará, we have almost all the adjacent forests deforested, but the mangrove remains intact", he states. 

Listen:

Traditional communities are "guardians" of mangroves, says an extractivist person

"It's from the mangrove
that we make our living.
It's our
survival",
explains João
Carlos da Silva

A pedagogue and social communicator, Mailton Silva dos Santos deeply understands the importance of mangroves in the Amazon. He is proud to be part of this history of conservation and respect for nature. He lives in the community of Santo Antônio do Trombetas, in the municipality of Santarém Novo, Northeast of the Pará State, where more than 300 families live. There, he works to raise awareness about the ecosystem and believes that union means strength.

"We only achieved this accomplishment of having the most preserved mangroves in the world due to the participation and involvement of everyone. The mangrove is extremely important and it serves as a nursery for several species, as the water depth is home to the spawning of several fish species, which also contributes to the nutrition of the extractive people. Besides, mangrove has outstanding and unique vegetation, including trees such as “tinteiro”, “siriubeira” and “mangueiro”. It is a region that absorbs much more carbon than dryland forests, protecting the area from erosion and has great cultural importance. In many territories, the mangrove is considered a sacred place, which inspires, for example, carimbó masters in the composition of songs. The more preserved the mangrove is, the better the fish, crab and all other species that the extractive people capture for food. And this generates more income, quality of life and dignity for our people", he highlights.

SURVIVAL

Extractivist João Carlos Gomes da Silva, known as "Donda", is the president of the Association of Users of the Tracuateua Marine Extractive Reserve, also in the State of Pará. According to him, no one knows how to take better care of mangroves than Amazonians.

"The traditional communities here are true guardians of the mangrove. It is from the mangrove that we make our living... it is what guarantees our survival. It is the nursery for several aquatic and terrestrial species. More than 95% of the species we capture from the sea come from the mangrove. It is everyone's heritage and we must take care of it, as well as teach our children and grandchildren to take care of it too, so that this good relationship extends for several generations", he says.

INSPECTION

Researcher Pedro Walfir de Souza Filho points out that public authorities play a crucial role in preserving mangroves, but it can be improved.

"We can improve a lot regarding inspection. We have excellent laws for the conservation of mangroves, an issue that was already a concern since the time of the Empire, with Dom Pedro, but we need to reinforce a policy of monitoring through inspection. And we have technology for that, including through the use of drones, which can contribute to a large-scale investigation. It is important to preserve now so we will not cry for what was lost, always acting before large areas are deforested", he adds.