https://doi.org/10.5194/soil-2019-26 This is just a preview and not the published preprint. §c Author(s) 2019. CC-BY 4.0 License. Spatial variability and sampling density of chemical attributes in archaeological black earths under pasture in southern Amazonas, Brazil Alan F. L. de Lima1, Milton C. C. Campos1, José M. da Cunha1, Laércio S. Silva2, Flávio P. de Oliveira3, 4 1 2 Bruno C. Mantovanelli , Elilson G. de Brito Filho , Romário P. Gomes 1Universidade Federal do Amazonas (UFAM), Humaitá, Amazonas, 69800-000, Brasil 2Universidade Estadual Paulista (UNESP), Jaboticabal, São Paulo, 14870-180, Brasil 3Universidade Federal da Paraíba (UFPB), Areia, Paraíba, 58397-000, Brasil 4Universidadae Federal de Santa Maria (UFSM), Santa Maria, Rio Grande do Sul, 97110-566, Brasil Correspondence to: Milton C. C. Campos (
[email protected]) Abstract. Spatial mapping of soil chemical attributes is essential for sampling efficiency and agricultural planning management, ensuring a regional development and sustainability of the unique characteristics of archaeological black earths (ABEs). Thus, this study was developed aiming at assessing the spatial variability and sampling density of chemical attributes in soils of ABEs under pasture in southern Amazonas, Brazil. A sampling grid of 56 × 80 m with regular spacings of 8 m was installed in the experimental area and samples were taken from the crossing points at depths of 0.0–0.05, 0.05–0.10, and 0.10– 0.20 m, totaling 264 georeferenced points. The chemical attributes pH in water, organic carbon, Ca, Mg, K, P, Al, and potential acidity were determined in these samples, while CEC, SB, V, t, T, and m were calculated.