Classificação e análise biohidrogeomorfológica das áreas úmidas de Minas Gerais: integração multicriterial, multiescalar e geoespacial

Abstract

Wetlands are ecosystems or functional units that occur in different abiotic and biotic contexts and which have varied genesis, typologies and spatiotemporal dimensions. The environmental functions provided by wetlands are very diverse and of significant relevance, such as: aquifer recharge, maintenance of bodies of water, carbon storage and habitat provision. The preservation and sustainable management of wetlands require knowledge of their main characteristics and the interrelationships with the environments in which they are located. Therefore, inventories and classifications of wetlands play a fundamental role in allowing the systematic analysis of their distribution, extent, types and main characteristics, providing support for the establishment of monitoring programs, research, and management and conservation policies for these ecosystems, in an integrated environmental approach. In this direction, the main purpose of this thesis is to develop a proposal for a geospatial biohydrogeomorphological classification of wetlands in the State of Minas Gerais, organized into regional scalar levels, including the analysis of their distribution in the territory, the interpretation of their types and characteristics, as well as the identification of potential areas of significant relevance for environmental protection. In order to achieve this goal, through the selection and crossing of geospatial data, an inventory of the wetlands of Minas Gerais (Brazil) was structured with a total of approximately 8,133.76 km². To classify the wetlands in this inventory, two scalar levels of analysis were structured – Level 1-N1 (regional) and Level 2-N2 (sub-regional) – and was also proposed a third level – Level 3 – of individual evaluation of examples of wetlands in the local context. The geospatial biohydrogeomorphological parameters that constitute the classification levels were defined and structured considering their role in the formation of wetlands, their types, characteristics and/or functions and their scale of analysis. N1 has four parameters: geomorphological domains, aquifer systems, rainfall measurements and biomes; N2 also has four parameters: geomorphological units, aquifer types, water deficit and ecoregions; and Level 3 has six parameters: relief forms, altimetry, slope, terrain forms (slope shape and direction of water flow), watercourse order (when applicable) and phytophysiognomies (vegetation types). In sequence, the wetlands in the inventory were classified based on the crossing of the units of the N1 and N2 parameters, isolated and combined with each other, and their distribution in the territory and the types of environments with greater occurrence and potential to give rise to wetlands, as well as interpreting their characteristics, sources of inflows, types and/or possible environmental functions. For the N1N2 combination, specific sections of areas in the state were developed to present a general overview of the characteristics of the wetlands in the inventory. Examples of the classification of wetlands into the three levels were then presented to illustrate and validate the classification proposal. As part of the classification, the occurrence of wetlands was also analyzed in relation to the overlapping of territorial management instruments: Priority areas for conservation (state and federal), Priority areas for the creation of Conservation Units-UCs, Atlantic Forest Biosphere Reserve, Caatinga Biosphere Reserve and Espinhaço Biosphere Reserve. A map of potential areas of significant environmental relevance for the protection of wetlands in Minas Gerais was outlined, forming a regional panorama for the delimitation and/or expansion of new UCs from the perspective of the diversity, relevance and conservation of wetlands to maintain their functions environmental. It is expected that this thesis can subsidize new research and support public actions aimed at protecting and managing these ecosystems in an integrated way with the environment, at different scales of planning analysis and territorial management.