Summertime CO2 fluxes and ecosystem respiration from marine animal colony tundra in maritime Antarctica

Bacterial diversity is strongly associated with historical penguin activity in an Antarctic lake sediment profile

“…Penguin activity in maritime Antarctica strongly influences the biogeochemistry of soils and sediments, through the deposition of a large amount of penguin guano, which has produced so-called ornithogenic soils and sediments 19 20 21 22 ; these soils and sediments are particularly rich in organic carbon, nitrogen, and phosphorus 23 24 25 26 . Microorganisms are crucial for the decomposition and mineralization of organic matter, and carbon and nitrogen biogeochemical cycles in these ornithogenic ecosystems 27 28 29 30 31 .…”

The current response of soil thermal regime and carbon exchange of a paraglacial coastal land system in maritime Antarctica

“…ST, SM, nutrient contents, and, especially, biological activity (fauna and flora effects), are reported to drive carbon uptake and release in MA (Cannone, Binelli, Worland, Convey, & Guglielmin, ; Zhu, Bao, Wang, Xu, & Liu, ; Thomazini et al, ). The CO 2 sink strength reported in the MC is mainly attributed to the vegetation associated with hydromorphic environment, creating a thick continuous moss mat.…”

“…However, the extensive moss carpets have a greater capacity of CO 2 uptake (up to seven times) compared with the well-drained mixed vegetation community (MLC). Previous studies of carbon dynamic in MA were carried out with a low number of measurements, and no temporal series were recorded (Mendonça, La Scala, Panosso, Simas, & Schaefer, 2010;Zhu, Bao, Wang, Xu, & Liu, 2014), making it difficult to interpret NEE dynamic over a diurnal cycle. This pattern is now confirmed and supported by consistent NEE field campaign.…”

“…Previous studies indicated that vegetation, ST, and SM are the most important variables related to soil CO 2 emissions (Mendonça, La Scala, Panosso, Simas, & Schaefer, ; Carvalho et al, 2013; Thomazini et al, , 2015, 2016; Zhu, Bao, Wang, Xu, & Liu, ). Zhu, Bao, Wang, Xu, and Liu, (2014) reported NEE (net ecosystem exchange) values ranging from −0.23 to 0.03 μmol CO 2 m −2 s −1 in seal and Skua colony areas, as well as a strong sink effect in moss carpets (−0.54 to −0.15 μmol CO 2 m −2 s −1 ) in Ardley Island.…”

“…After a glacial condition, a paraglacial period is installed under nonglacial conditions, when rapid changes are expected due to greater instability at this transitional period (Church & Ryder, 1972;Ballantyne, 2002;Fretwell, Hodgson, Watcham, Bentley, & Roberts, Panosso, Simas, & Schaefer, 2010;Carvalho et al, 2013;Thomazini et al, 2014Thomazini et al, , 2015Thomazini et al, , 2016Zhu, Bao, Wang, Xu, & Liu, 2014). Zhu, Bao, Wang, Xu, and Liu, (2014) reported NEE (net ecosystem exchange) values ranging from −0.23 to 0.03 μmol CO 2 m −2 s −1 in seal and Skua colony areas, as well as a strong sink effect in moss carpets (−0.54 to −0.15 μmol CO 2 m −2 s −1 ) in Ardley Island. Mendonça, La Scala, Panosso, Simas, and Schaefer (2010) found greater mean ecosystem respiration values (4.13 μmol CO 2 m −2 s −1 ) in Deschampsia antarctica patches over organic-rich soils, whereas bare soils presented lowest ecosystem respiration values.…”