Solos do Pantanal Sul-Mato-Grossense: caracterização, classificação comparativa e serviço ecossistêmico

Abstract

The study of soils is effective for stratifying and understanding the functioning of landscapes. Soil classification, aiming for the most precise correspondence possible in national and international taxonomic systems, is a challenge for scientific communication and knowledge transfer in soil science. The objectives of this study are: (1) to perform a physical, chemical, and organic matter characterization of soils from lacustrine and forest systems in the Pantanal of Mato Grosso do Sul; (2) to classify soils and compare equivalences between the SiBCS and WRB taxonomic systems in twelve representative pedons of the area; and (3) to explore the relationship between soil and litter for understanding ecosystem services of Pantanal soils. For this, the following methodological procedures were conducted: fieldwork for sample prospecting and soil classification in the regions of Nhecolândia, Miranda, and Abobral; analytical determinations of soil attributes and chemical composition of litter; and statistical analyses aiming at data synthesis and presentation of results. Bays stand out for higher potential acidity (H+Al), slightly elevated organic matter content, and availability of metallic ions, especially Fe; in ridges, higher mean P-rem and very sandy texture are more evident, whereas soils from salt flats are related to more alkaline pH values, high base saturation, and high sodium saturation indices (ISNa). In SiBCS, four soil classes were identified at the first categorical level (Espodossolo, Gleissolo, Neossolo, and Planossolo), while WRB presents three Reference Soil Groups (Arenosol, Stagnosol, and Solonetz). Soils classified according to SiBCS do not have their equivalent correspondence in WRB due to discrepancies related to attributes such as C-org, color, pH, and salinity. Soils interact with litter chemical composition, highlighting the great interdependence between soil properties and nutrient cycling, influencing litter chemical composition and decomposition rate, as indicated by significant correlations between N, P, Ca, Mg, Mn, and C/N ratio with physical, chemical, and organic matter attributes. Carbon, despite being abundant in litter, showed weak correlation with soil constituents.