Nutrients and cations content in soil solutions from the present and abandoned penguin rookeries [Antarctica, King George Island]

Penguin rookeries are one of the main sources of nutrients for the poor ecosystems of Antarctica. At the current penguin rookeries, and in their vicinity, nitrogen rich ornithogenic soils are formed. Relict ornithogenic soils created at the abandoned rookeries hundreds or even thousands years ago are rich in phosphates. In the region of maritime Antarctica, water plays an important role in distribution and redistribution of nutrients (surface flows and percolation). Soil decomposition processes result in cations and nutrient release. In nutrients originating from relict ornithogenic soils of the Antarctic tundra, phosphates are the dominating elements; while in nutrients originating from contemporary ornithogenic soils nitrogen (mainly ammonia) is the main ingredient. Mineral soils free of penguin influence contain minute amounts of nutrients. Low pH of soil solutions (<4) causes increase of dissolving of phosphate complexes. Near penguin rookery, pH was lowest (2.73-3.33) and intermediate (2.92-3.77) in relict soils. The values of pH were the highest in soil solutions from mineral soil (5.43-7.33). High concentration of cations (mainly K) in soil solutions from the ornithogenic soils and relict ornithogenic soils, suggest their organic (animal) origin.