Using remote sensing images for stratification of the cerrado in forest inventories

Abstract

Remote sensing imagery can be a very useful auxiliary tool for native forests inventory. Thus, the objective of this study was to evaluate the stratification of a cerrado (Brazilian savanna) patch based on visual image interpretation techniques as well as to compare the errors from two sampling designs, the Stratified Random Sampling (SRS) and the Systematic Sampling (SS).The study area corresponds to a cerrado sensu stricto patch located in the municipality of Papagaios, Minas Gerais, Brazil. The cerrado wood volumes were obtained from a forest inventory field campaign where 32 plots were measured systematically. The study area was stratified based on a visual interpretation of a Landsat 5 TM image, and the strata formed were: "Strata I", "Strata II", "Strata III", water and riparian forests. There was a reduction of 43% on the inventory errors using the SS estimators compared to the inventory errors using the SRS estimators. We concluded that the stratification based on image interpretation techniques was efficient since there was a reduction on the cerrado inventory errors.