Chemical features of floodplain soils under different land-uses in the Solimões/Amazon River basin

• Published in: Revista Brasileira de Ciência do Solo 2022-01, Vol.46
• Main Authors: Alfaia, Sonia Sena, Ayres, Marta Iria da Costa, Neves, Acácia Lima, Uguen, Katell, Miller, Robert Pritchard, Fajardo, Juan Daniel Villacis, Bakker, Alexandre Pereira, Ticona-Benavente, César Augusto
• Format: Article
• Language: English
• Subjects: SOIL SCIENCE
• ISSN: 1806-9657; 1806-9657
• DOI: 10.36783/18069657rbcs20220005

ABSTRACT Most studies regarding the impacts of agricultural systems on soils of the Amazon region of Brazil have been carried out on upland soil, locally known as terra firme. Information regarding the impacts of different land-use systems on floodplain soil properties is still scarce. There is a need to broaden this knowledge to understand this Amazonian ecosystem better, especially how its soils respond to human interventions. This study aimed to describe the major chemical features of floodplain soils along the Solimões-Amazon Rivers and the effects of different land-use systems on soil nutrient levels. Sixty-two different land-use systems were sampled in 15 communities located in three different regions of the Solimões/Amazonas River floodplain complex: Upper and Middle Solimões (UMS), Lower Solimões and Middle Amazon (LSMA), and Lower Amazon (LA). Soils under cultivation showed a high availability of Ca2+, Mg2+, and P and low levels of exchangeable Al, in contrast to soils under forest and secondary vegetation, which were more acid and showed higher levels of exchangeable Al. Although most of the samples showed high contents of K+, for some areas, the low level (K+