Chemical and physical attributes and calcium, magnesium, potassium, and phosphorus in the soil of murundu fields in Brazil

Abstract

RESUMO Campos de murundus (CM, Al 3+ and H+Al] and physical [texture and bulk density (Bd)] soil attributes and calculate the organic matter (OM) and nutrient stock (P, Ca, Mg, and K) in soils of FM located in the Guapore River basin in Mato Grosso. Thirty-six sampling points were selected, and soil samples were collected from two environments: the murundu and plain area surrounding (PAS). At each sampling point, mini trenches of 0.5 × 0.5 × 0.4 m were opened and disturbed and undisturbed soil samples were collected at depths of 0-0.1, 0.1-0.2, and 0.2-0.4 m. In the Principal Component Analysis the variables H+Al (49%) and OM (4%) were associated with the F1 component and sand content (47%) with the F2 component. The FM had lower pH values and higher concentrations of K + , P, and H+Al than PAS at all depths (p < 0.05). Additionally, FM stocked up to 433, 360, 205, and 11 kg ha -1 of Ca, Mg, K, and P, respectively, for up to a depth of 0.2 m. The murundu stored two times more K and three times more P than that in the PAS. Our results show that the FM has high sand content and Bd greater than 1.5 Mg m -3 , high acidity, low OC content, and low nutrient concentrations. Thus, special care must be taken to preserve FM such that human intervention does not trigger environmental imbalances.

Natural backgrounds and reference values of trace-element in earth murundus fields on the Southern Amazon

“…It was observed that Pb contents were lower than those reported in the literature for other soils (Pierangeli et al, 2009;Santos & Alleoni, 2013;Pierangeli et al, 2015). This fact may be related to the soil granulometry of these murundus fields: 200 and 250 g of kg -1 of clay in the flat and murundu area, respectively (Santos et al, 2015).…”

“…The low levels of trace elements observed here reflect the source material. These are soils formed from unconsolidated sediments of the Guaporé Formation (Santos et al, 2015), in addition to leaching processes favored by the solubility of the elements (Olivie-Lauquet et al, 2001), which may further decrease the natural levels of these elements in these soils. presented mean values of several elements in native vegetation soils in the state of Mato Grosso.…”