Temporal analysis of drought coverage in a watershed area using remote sensing spectral indexes

Abstract

The development of several time series analysis programs using satellite images has provided many applications based on resources from geostatistics field. Currently, the use of statistical tests applied to vegetation indexes has enabled the analysis of different natural phenomena, such as drought events in watershed areas. The objective of this article is to provide a comparative analysis between NDVI and EVI vegetation index data made available by MOD13Q1 project of MODIS sensor for drought mapping using vegetation condition index (VCI) in the Serra Azul stream sub-basin, MG. The methodology adopted the Cox-Stuart statistical test for seasonality analysis and Pearson's linear correlation to verify the influence of different indexes on delimitation of drought in a watershed. The results indicated the NDVI vegetation index as more efficient than EVI in spatial characterization of studied watershed region, mainly in identification of seasonality. The VCI proved to be highly feasible for monitoring drought in study period between 2013 and 2018, allowing the effective delimitation of drought conditions in the Serra Azul stream sub-basin. In addition, the effectiveness of MODIS sensor data in characterizing drought events that affected the study area was proven.

Association between forest resources and water availability: temporal analysis of the Serra Azul stream sub-basin

“…In the study region, Dutra (2021) discusses, through water balance analyses, that changes in land use have provided a decrease in the maximum storage of the basin's water volume, since the expansion of urban areas together with the agricultural and mining activities in the region have provided greater suppression of vegetation and consequent changes in the sub-basin's hydrological cycle, such as the reduction in the water volume of the reservoir throughout the analyzed time series. According to Dutra (2021) and Dutra et al (2020Dutra et al ( , 2021, the main consequence of these activities is the increase in the output of water, mainly due to grants, in relation to the inflow, arising from natural processes, such as precipitation. In addition, according to Dutra (2021) 2017) reported that the connection between forest areas must be ensured to guarantee local biodiversity.…”

Biomass Model and Water Balance Application for Watershed Drought Analysis

“…The Serra Azul stream sub-basin is especially important for the water supply of Belo Horizonte Metropolitan Region because of the presence of a water supply reservoir managed by Companhia de Saneamento de Minas Gerais (COPASA in Portuguese). This region is located between the parallels 20º 15 'and 20º 00' south latitude and the meridians 44º 15 'and 44º 35' west longitude (Figure 1), encompassed in the municipalities of Mateus Leme, Igarapé, Juatuba and Itaúna (Dutra et al 2021;Dutra, Brianezi & Coelho 2020;Dutra, Elmiro & Garcia 2020).…”

“…This process was registered in several regions of the world, mainly in the year 2015, such as in Western Europe and South America, and has been the focus of studies in academic area. These studies aim to understand how far the extreme of this event can unbalance the hydrological cycle and how the impacts can be mitigated and managed (Changnon et al 2000;Dutra 2021;Dutra et al 2021;Luz et al 2021;Mishra & Singh 2010;Van Lanen et al 2016).…”

“…Thus, it is of great importance to create mitigation measures, such as disaster monitoring and management plans to avoid serious consequences of drought in a region. In this perspective, the use of effective tools, such as remote sensing technologies, have allowed the observation and production of estimates using times series data to statistical and geospatial analysis (Anderson et al 2016;Dutra et al 2021;West, Quinn & Horswell 2019).…”

Uso e Cobertura do Solo após Eventos de Queimadas no Município de Floresta em Pernambuco

“…Tal correlação pode ser positiva para os valores acima de 0 ou negativa para os menores que 0, sendo que os máximos são 1 e -1, respectivamente. Assim, esse método possibilita a verificação da interferência de uma variável em relação a outra (Equação 9) (Dutra et al, 2021;Fialho e Santos, 2021).…”