LAND -USE and land-cover change processes in Pampa biome and relation with environmental and socioeconomic data

摘要

Pampa biome in the last years has gone through a process of change in land use, chiefly due to the conversion of grassland vegetation for agriculture of grains and silviculture. The main objective of this work is to analyze processes of Land-Use and Land-Cover (LUCC) in the Brazilian Pampa Biome, mapped from Multitemporal data of MODIS sensor, including the main processes of landscape transformation. The period studied was 2000 and 2014, and MODIS-EVI images and night DMSP-OLS images were used for generation of land use and cover maps, through decision tree classification. IBGE census sectors' limits were used. To investigate the processes of landscape transformation of Pampa Biome, environmental variables were used including geomorphometric data, landscape metrics and climate data and socioeconomic variables. Local (GWR) and global linear regression models were used in addition to procedures for spatial clustering (SKATER algorithm). Reduction of around 25% of grassland class in 15-year interval was verified, from 10,252,740 ha to 7,676,208 ha. On the other hand, agriculture areas like Soybean class obtained 145.56% increase in their total area, from 855,087 ha in 2000, to 2,099,837 ha in 2014. Silviculture class also presented increase of over 167% of its total area. The main factors in the global regression model that negatively contributed to grassland degradation process are: population density, height against the closest drainage (HAND Model) and degradation patches in the grassland. Factors that positively contributed are: population residing in domiciles, average of number of residents in domiciles, Soybean expansion patches and distance from Soybean expansion process. It was concluded that orbital data along with geoprocessing techniques provided tools for monitoring changes in land use and cover.