Geoquímica de Terrenos Urbanos Modificados pela Humanidade e Serviços Ecossistêmicos (SE): o Caso de Santa Maria (RS, Brasil)

Abstract

Human agency leaves several marks on the environment, which includes deep modifications on the geological surficial layers of the planet, including the formation of technogenic ground. In the last decades, urban expansion has been accompanied by an increase in the extension of degraded lands, which includes modifications in the ground by the introduction of anthropogenic materials and actions such as cutting, revolving and compaction, which affects ecosystem functions of these substrates. In Brazil, this process has intensified since the second half of the 20^th Century. Thus, the objective of this work was to investigate the changes in the ground geochemical properties of the city of Santa Maria (RS) and how it may affect the possible ecosystem services provided by these soils. For this purpose, a morphological description of soil profiles to identify the existence of anthropogenic layers was carried out and laboratory tests were conducted to determine pH_water, pH_KCl, Ca2, Mg2, K, Na, Al3, H+Al, Cu, Zn and calculation of S, Al% and V%. The results pointed out that there is an enormous variation of anthropogenic constituents in the material, which are capable of altering both the properties of the ground surficial layers as well as their functions and the provided ecosystem services.