Intensity of land use by pasture as result of pedogeoclimatic
characteristics and anthropogenic management
Abstract
In the world, the most significant change in the ecosystems structure is
the conversion from natural land surface into cultivated systems. In
2018, 26.8% of the Brazilian territory was occupied by agricultural
activities, from which 73% is pasture. Considering that the management
adopted in Brazilian pastures is incipient and leads to degradation,
there is a need to characterize the state of the pastures to diagnose
the intensity of this use on the soil. However, the diagnosis of large
areas using satellites with more detailed resolution is limited by cloud
coverage and low temporal resolution. In this sense, the present work
aims to diagnose the intensity of land use by pastures (ILUP) in large
areas based on the mosaic of images from Landsat 8 (LS8), Landsat 7
(LS7), Sentinel-2 (S2), and MODIS. The methodology consists of
harmonizing the NDVI from LS7 and S2 satellites with LS8. For MODIS, the
harmonization was carried out based on ILUP obtained previously from
NDVI LS8. The methodology was applied at the Doce river basin (DRB). The
combination of different sensors allowed to overcome the cloud coverage
limitation. DRB has 61.3% of its area occupied by pastures and 78.2%
of them have some degree of degradation. ILUP was dependent on DRB’s
pedological and climatic characteristics. This dependence is enhanced
due to pasture management in the basin, mainly characterized by
continuous grazing, which commonly leads to overgrazing scenarios. The
areas with great rainfall seasonality and associated with
Acrisols/Cambisols are the most susceptible to degradation.