Dados do Trabalho

Título

PHOSPHATIZATION OF MARITIME ANTARCTIC SOILS: PENGUINS VERSUS GIANT PETRELS

Resumo

The phosphatization, promoted by ornithogenic influence, is one of the main pedogenetic processes driving weathering and pedogenesis in the Maritime Antarctica (MA) region. The main objective of this work was to compare the physical and chemical characteristics of ornithogenic soils under current and past influence of penguins (Pygoscelis papua and Pygoscelis antarticus) located in volcanic stacks or marine terraces and giant petrels (Macronectes giganteus) located in outcrops rocks inside the raised platform. For this, 15 profiles of ornithogenic soils were collected and described in Harmony Point, Nelson Island, MA. Routine physical and chemical analyzes were performed and descriptive statistics and principal component (PCA) analyses were applied. The PCA of the physical attributes explained 92.7% of the data variance, while that of the chemical attributes explained 69.9%. Due to the marine influence and the location in an environment recently exposed to weathering processes, the soils under penguins’ influence showed higher contents of coarse sand, base saturation, sodium saturation, and remaining P, due to the low clay content and weak P adsorption. The P and Zn contents were more significant in these soils due to the greater volume of guano input by penguins. The soils under petrels’ influence showed the highest values of organic C, total N, H+Al, and CEC, due to the greater development of vegetation and contribution of organic matter, with fertilization by guano. Although penguins contribute to a more intense phosphatization, soils under their influence are in more unstable environments and exposed to erosion, under strong westerly winds coming from the Drake. On the other hand, soils under the influence of petrels occur in a more stable area, with a longer time of exposure and vegetation development, which favors greater soil development and accumulated organic matter content.

Palavras-chave

ornithogenesis; phosphates; flying birds; pedoenvironmets.

Instituição financiadora

CNPq and CAPES.

Agradecimentos

Terrantar/Permaclima projects, PROANTAR, Brazilian Navy and UFV.