Sensoriamento remoto aplicado na evolução paisagística de uma microbacia

Abstract

The present study aimed at evaluating of the scenery evolution of the watershed of Two Waters River - Botucatu (SP) through the use of the System Geographical Information - Idrisi 32 and of satellite image digital satellite, bands 3, 4 and 5 of Sensor TM, of Landsat 5, of the orbit 220, point 76, quadrant A, passage of June, eightth, 1997 and photographs vertical aerial of 1962, in scale 1:25000, in the 35 years-old period. The study area locates among the geographical coordinates 22o

43' 49" to 22o

49' 29" of longitude S and of 48o

17' 53" to 48o 22' 03" of longitude W Gr., presenting an area of 4007,19ha. The vegetative cover in 1962 presented the following results: pastures - 21,72%; brushood - 70,29%, forest - 1,14% and exposed soil - 6,85% and in 1997: reforestation - 19,36%; forest - 4,25%; pastures - 26,80%; I use agricultural - 26,84%, exposed soil - 1,21% and brushood - 21,54%. The results allowed verifying that there was a significant increment in the areas of agricultural use and reforestation in function of the reduction of the areas of brushoods. The images of Sensor TM of Landsat 5, allowed the mapping of the land use of the watershed in a fast and reliable way, besides supplying an excellent database for future plannings. The GIS - Idrisi through its different modules for georeferencing, digital classification of the land use and mathematical model allowed the discrimination of the lands use: reforestation, kills, pasture, agricultural use, exposed soil and brushood. The high index of occupation of the soil for agricultural use, pasture and reforestation in the basin (73%) they reflect the predominance of the agriculture and of the regional forestry.