The present study aimed to understand the process of change in land use and land cover in the
Rio Formoso River Basin (BHRF), its relationship with the territorial planning proposed in the
Watershed Plan (PBH-Formoso) and its environmental implications. For this, data from the
coverage and use mapping provided by the 5th Collection of Mapbiomas (2020), between the
years 2007 to 2019, the Base Cart of the state of Tocantins and the Rio Formoso Watershed
Plan were used. The method consisted of quantifying the thematic classes, performing the
annual transition through ArcGIS software, analysis using the Cross Tabulation Matrix
proposed by Poncius-Jr et al. (2004), and comparison with the environmental zoning established
in the Watershed Plan and the total limit of the study area. Nine classes of land cover and use
were identified, namely: savanna formation, pasture, forest formation, soybean, grassland
formation, temporary crops, water bodies, non-vegetated areas and urban infrastructure, cited
in order of greatest contribution to the BHRF landscape. There was a total decrease in natural
areas (grassland, forest and savanna), where only the forest formation shows a subtle recovery
from the year 2018, and an increase in agricultural areas (pasture, temporary crops and
soybeans). On average, annually, about 3.04% of the total area of the basin undergoes some
type of alteration and 96.96% shows persistence of coverage and use. In the general context,
the classes of pasture and savanna are the ones that most convert and are converted into other
uses, demonstrating their intermediate role in the context of the basin. The grassland and forest
formations were the ones that proportionally lost the most areas, demonstrating relative
passivity, while the temporary crops and soybean cultivation are the main beneficiaries, playing
an active role in the transformation of the environment, while the other classes participated little
in the process. In the internal context of the agricultural classes, between 2007 and 2013, the
pasture areas were mostly converted to temporary crops, so that from 2013 to 2019, the main
beneficiary became the cultivation of soybeans, demonstrating the prevalence of this specific
crop in the region, emphasizing that its main growth is due to this aspect, with little expressive
increase over natural areas. Regarding natural areas, the marked conversion of forested areas
into savannas suggests a possible impact of the hydrogeological and climatic context on the
growth of species that are more resistant to water deficit. The zoning established in PBH-
Formoso had little influence on the transition process, since in areas of high agricultural use
there was quantitative maintenance of natural areas and in protection zones, these areas were
reduced. Thus, it is suggested to review the PBH-Formoso that includes environmental zoning
that takes into account pre-existing uses and their behavior, the definition of areas of
environmental interest based on ecological diversity and propensity to recharge aquifers,
institution of mechanisms that consider the power relationship between actors and their
effective participation in the decision-making process to reconcile conflicts.
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