Navegando por Assunto "Ecossistemas amazônicos"

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Acesso aberto (Open Access)
Análise ecológica da ostracofauna (crustacea) e meiofauna bentônica associada como bioindicadores ambientais na ilha de Cotijuba, Belém (PA), Amazônia
(Universidade Federal do Pará, 2025-02-27) BRITO, Maurício de Souza; PEREIRA, Ana Paula Linhares; http://lattes.cnpq.br/8369046011837903
The uncontrolled occupation of environmental protection areas (APA) in Belém-PA and candidates for APA, such as Cotijuba Island, has intensified the environmental impacts in the region. To mitigate these effects, Conservation Paleobiology integrates historical data on the distribution of fauna and flora, connecting past, present, and future. In turn, ostracods, small crustaceans sensitive to environmental variations, which are part of the benthic meiofauna, provide information about changes in ecosystems through the analysis of their communities and shells, formed from the calcium carbonate in the water. In this way, the survey of the ostracofauna and associated meiofauna on the island of Cotijuba allowed the use of these groups as bioindicators. The research was conducted during the rainy, transitional, and less rainy seasons, at two beaches: Flexeira, less impacted, and Farol, more influenced by human activities. During the campaigns, surface samples were collected in the inframarine, intertidal and supramarine zones, as well as sediment cores, physico-chemical water measurements, and beach profiles. The results showed Farol beach as reflective and Flexeira beach as dissipative, in addition to physical-chemical parameters with low influence on the organisms. The benthic meiofauna recorded 10 distinct classes: Oligochaeta, Polychaeta, Insecta (Diptera and Trichoptera), Malacostraca (Amphipoda), Arachnida, Ostracoda, Hydrozoa, Gastropoda, Bivalvia, and Rhabditophora. Approximately 84% of the specimens are from Flexeira beach, with this proportion being higher when only ostracods are analyzed (89%). Despite the lower abundance at Farol beach, a large number of cocoons of Trichoptera pupae were observed, known for their sensitivity to pollution and environmental changes, indicating a relatively healthy environment. However, a low abundance of ostracods was observed, which may be related to abiotic factors, such as the type of beach and coarse sediments. Moreover, the overall abundance of meiofauna in Cotijuba was also considered low, even without indications of significant anthropogenic intervention, which suggests a relationship between the low number of specimens and hydrodynamic conditions that intensify erosive and depositional processes. The record of a new species is highlighted: Cyprideis cotijubensis sp. nov., as a potential bioindicator of recent ostracofauna in river estuaries in the Amazon. The project also resulted in the digital book “Cartilha Digital Preserva Amazônia”, aimed at raising awareness about the conservation of the Amazon.
Acesso aberto (Open Access)
Mudanças de uso e cobertura da terra e as perspectivas da abordagem nexus água, alimento e ecossistemas em bacias hidrográficas costeiras do Nordeste Paraense, Amazônia Oriental
(Universidade Federal do Pará, 2024-02-23) DUTRA, Vitor Abner Borges; TOLEDO, Peter Mann de Toledo; http://lattes.cnpq.br/3990234183124986; LIMA, Aline Maria Meiguins; http://lattes.cnpq.br/6572852379381594; https://orcid.org/0000-0002-0594-0187
The Amazon is increasingly gaining global spotlight, despite chronically suffering the massive destruction of its ecosystems. In this context, this thesis focused on the question “to what extent will changes in land use and cover modify the landscapes of watersheds in the Eastern Amazon by 2030 and how do these changes imply the achievement of environmental goals to promote sustainable development?”. Thus, three scientific articles were prepared, where the first two dealt with the region’s spatio-temporal changes in the recent past and near future, and the third designed an integrated Nexus approach of water, food and ecosystem indicators, aligned with current environmental policies. In the first article, the dynamics of the landscapes of three watersheds between 1985 and 2019 were evaluated. The results revealed a significant conversion from forest to pasture of approximately 1,000 km², with an increase in forest fragments from 2547 to 6604, highlighting the importance of measures conservation and recovery of vegetation for the maintenance of local ecosystems. In the second article, simulations of future land cover scenarios for the region were carried out, with an emphasis on deforestation and its greenhouse gas emissions, under three hypothetical scenarios. The results indicated that, regardless of the scenario, the region could face a significant increase in deforestation and emissions by 2030, with deforestation varying from 90 thousand hectares to 125 thousand hectares, and respective greenhouse gas emissions between 3.67% and 5.09% of total emissions of the Pará State, highlighting the urgency of implementing policies for the conservation and recovery of native vegetation. In the third article, the interconnection of water, food and ecosystem indicators was explored, under the backdrop of the Sustainable Development Goals of the 2030 Agenda and the Amazon Now State Plan. We identified some challenges, such as low environmental compliance and high pressure on water and forestry resources. However, opportunities for improvements were also identified, such as encouraging the adoption of agroforestry systems, the recovery of permanent preservation areas around water resources and the use of thriving crops from the Amazon bioeconomy, as they can result in socioeconomic and environmental improvements in the region. In summary, the studies demonstrated the complexity of environmental changes in the Eastern Amazon and the importance of an integrated approach to address pressing challenges. For a successful experience, actions must be coordinated between governments, local communities and other stakeholders, in order to guarantee the conservation of local ecosystems and the well-being of current and future generations.