Main Article Content
In Brazil there are six well-defined biomes and the Caatinga represents 9.92% of the total area. This biome is exclusively Brazilian and very rich in biodiversity. Because it has low resistance to human interference is necessary to know the important factors in monitoring the biome. Vegetation coverage and climate are two of these factors, as they indicate the intensity of human activity and the wear caused with time. Normalized Difference Vegetation Index (NDVI) has been recently explored in the description of tree phenology. In this study we sought to associate NDVI/Landsat values to a climatic variable (phenomena El-Nino and La-Nina - NINONINA) in order to describe the phenological behavior of the Caatinga in the Parque Nacional da Serra das Capivaras in the state of Piauí/Brazil. A time series analysis was carried out, describing the intrinsic parameters of the series (Seasonality and Trends), the forecast of NDVI values using SARIMA model and co-integration between NDVI and NINONINA series. The results showed that the NDVI series presents seasonally, but does not exhibit a trend. The forecasting process presenting relatively low error at a 95% confidence interval. Finally, it was observed that the NDVI series is co-integrated with the NINONINA series.