Analysis of the structure and distribution of caatingas vegetable coverage in different areas of drought in the São Francisco Valley (Bahia and Pernambuco) in the last three decades

In recent years, the reduction of the vegetation cover of the caatingas has been attracting attention and encouraging studies that seek to understand the retraction dynamics of its plant covers. In this sense, the objective of this study is to analyze the structure of the vegetation cover in differe...

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Detalles Bibliográficos
Autores: Aquino, José Welton Coelho de, Santos, Antônio Marcos dos
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:Brasil
Institución:Universidade Federal de Santa Maria (UFSM)
Repositorio:Geografia Ensino & Pesquisa (Online)
Idioma:portugués
OAI Identifier:oai:ojs.pkp.sfu.ca:article/45245
Acceso en línea:https://periodicos.ufsm.br/geografia/article/view/45245
Access Level:acceso abierto
Palabra clave:Dryland vegetation
Desertification
Degradation of plant cover
Remote Sensing
Caatingas
Desertificação
Degradação da cobertura vegetal
Sensoriamento Remoto
Descripción
Sumario:In recent years, the reduction of the vegetation cover of the caatingas has been attracting attention and encouraging studies that seek to understand the retraction dynamics of its plant covers. In this sense, the objective of this study is to analyze the structure of the vegetation cover in different areas of the caatingas in the last three decades, and investigate factors that may influence the behavior of plant cover distribution in two monitoring areas in the states of Pernambuco and Bahia (Brazil).  For this, satellite images obtained from the TM and OLI sensors, coupled to the Landsat 5 and 8 satellite, were submitted to radiometric calibration, extraction of the Soil Adjusted Vegetation Index (IVAS) and supervised classification. The study showed that over the approximately 30 years of study, there was great variability in the dynamics of changes in the caatinga areas, but prevailing a trend of decrease in the   Closed Caatinga being replaced by the Semi-open Caatinga and Open Caatinga. It was also found that mainly in the last 11 years there has been an increase in the areas of agriculture / pasture / gramíneo-woody caatinga. These changes are driven by anthropic changes, mainly for the growth of pasture areas and the decrease of total rainfall in recent years.