3.1. Data use
Our study aims to test and use remote sensing to study the evolution and the state of vegetation in the forest of Tenira. Completion of this work will necessitate the availability of the series of satellite data dating from August or September (data 1: 1987, data 2: 1992, data 3: 2002, data 4: 2007, data 5: 2010, data 6: 2013, data 7: 2015, data 8: 2018), details on exploited landsat images are reported in table 1. Data were downloaded from the USGS global visualization viewer glovis on-demand interface (http://glovis.usgs.gov/). They allow us to appreciate the vegetation cover perennials, constituted plant stability element of landscape.