Space-time variability of vegetation by orbital platforms in the western Amazon

Abstract

ABSTRACT:Percentage maps (%) of forest cover derived from the annual product MOD44B were compared with the annual deforestation data from PRODES. PRODES data were used to calibrate the MOD44B (sub-pixel-level representation of surface vegetation cover estimates globally) annual images with the aim of evaluating the annual characterization of the deforestation dynamics and forest regeneration in the municipality of Bujari -Acre, Brazil, from 2000 to 2010. The percentage rates from MODIS were divided into forest cover categories (forested and deforested areas) by means of the Mann-Kendall (MK) non-parametric test used in each category. The results were satisfactory when compared with PRODES. The analysis of MOD44B product in the municipality, during the years 2001, 2004 and 2009, shows that there was an increase of the pixel frequency in the "Extremely High" category, which indicates regeneration of the area in the municipality of Bujari. Validations in situ should be done primarily to the regenerate areas.

EVI2 index trend applied to the vegetation of the state of Rio de Janeiro based on non-parametric tests and Markov chain

“…However, there is no rigorous control of Brazilian biomes in spatial scale, because biomes are constantly threatened by human activities such as farming, agriculture and real Estate occupation (ALEIXO et al, 2010). Given the need for evaluating the vegetation in large areas some vegetation indices were created the NDVI (Normalized Difference Vegetation Index) by Rouse et al (1974) and EVI (Enhanced Vegetation Index) by Huete et al (1997Huete et al ( , 1999Huete et al ( and 2002, both widely used in several dynamic studies on the vegetation (ZHANG et al, 2009;DELGADO et al, 2015;GOULART et al, 2015). Demarchi et al (2011) comment that sensory and spatial techniques help in the land use and occupation planning of a region; delimitation of PPAs, legal reserves and UCs; and maintenance of water resources and other areas recognized by the legislation as important for maintaining the environmental activities.…”