Soil analysis data for the eastern of Maracá Island, northern Brazilian Amazonia
The dataset provides information on soil texture and fertility for the eastern of Maracá Island, a fluvial island integrated to the Maracá Ecological Station, state of Roraima, northern Brazilian Amazonia. This area represents an ecotone zone in the southern region of the Guyana Shield, which is dominated by mosaics of ombrophilous and seasonal forests in contact with savanna areas. Our sampling took into consideration the PPBio (Biodiversity Research Program) 25-km2 research grid installed in the eastern of Maracá Island. We designed the sampling to be performed in 129 permanent plots located on six 5-km trails (E-W direction; see https://ppbio.inpa.gov.br for details on the PPBio grid structure) covering different environmental conditions. All plots were dispersed on the PPBio trails at distances ranging from 150 m to 250 m (flooded areas, rivers and savanna enclaves were not sampled). The fieldwork was carried out in September 2016 (end wet season), when we collected 129 soil cores to a depth of 20 cm (each one composed by two subsamples). Analysis were performed using methodology adopted by Embrapa (Embrapa. 2009. Manual de análises químicas de solos, plantas e fertilizantes. Embrapa Informação Tecnológica, 2. ed. rev. ampl. Brasília-DF. 627 p). The dataset is presented in four files: (i) study_site - a figure indicating location of the study area; (ii) locationID - identification of sampling units (unique code) and their geographical location (lat / long - WGS84), associated with altitude (m a.s.l.), slope (%) and canopy opening (%); (iii) soil_texture - soil particles composition (% - sand, silt, clay); (iv) soil_fertility - chemical variables analysis. This dataset was supported by project “Crescimento e mortalidade de árvores em florestas ecotonais de Roraima: efeito das condicionantes ambientais e da variabilidade climática” (Proc. CNPq n. 403591/2016-3). The Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq - Brazil) also provided a fellowship for R.I. Barbosa (CNPq 304204/2015-3). C.D.A. Villacorta was supported by postgraduate fellowship from the Organization of American States (OAS), while L.C.S. Carvalho was supported by a fellowship from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES/PNPD). Instituto Chico Mendes de Conservação da Biodiversidade (ICMBio) provided authorization for the study (SISBIO n. 52017).