Environmental observations from Station Ssagastyr during the first International Polar Year 1882/83 (digitized tables)

Vorliegender Band enthält die für alle internationalen Polarstationen obligatorischen meteorologischen Beobachtungen der russischen Polarstation an der Lenamündung für den Zeitraum vom 1. September 1882 bis 31. August 1883 und vom 1. September 1883 bis zum 6. Juli 1884.

Seawater carbonate chemistry, cell numbers and growth rate during experiments with dinoflagellates, 2007

The effects of dissolved inorganic carbon (DIC) on the growth of 3 red-tide dinoflagellates (Ceratium lineatum, Heterocapsa triquetra and Prorocentrum minimum) were studied at pH 8.0 and at higher pH levels, depending upon the pH tolerance of the individual species. The higher pH levels chosen for experiments were 8.55 for C. lineatum and 9.2 for the other 2 species. At pH 8.0, which approximates the pH found in the open sea, the maximum growth in all species was maintained until the total DIC concentration was reduced below ~0.4 and 0.2 mM for C. lineatum and the other 2 species, respectively. Growth compensation points (concentration of inorganic carbon needed for maintenance of cells) were reached at ~0.18 and 0.05 mM DIC for C. lineatum and the other 2 species, respectively. At higher pH levels, maximum growth rates were lower compared to growth at pH 8, even at very high DIC concentrations, indicating a direct pH effect on growth. Moreover, the concentration of bio-available inorganic carbon (CO2 + HCO3-) required for maintenance as well as the half-saturation constants were increased considerably at high pH compared to pH 8.0. Experiments with pH-drift were carried out at initial concentrations of 2.4 and 1.2 mM DIC to test whether pH or DIC was the main limiting factor at a natural range of DIC. Independent of the initial DIC concentrations, growth rates were similar in both incubations until pH had increased considerably. The results of this study demonstrated that growth of the 3 species was mainly limited by pH, while inorganic carbon limitation played a minor role only at very high pH levels and low initial DIC concentrations.

Groundfish survey data from the German Bight from 1902-08, 1919-23, and 1930-1932 and ICES International Bottom Trawl Survey (IBTS) quarter 3 data from 1991 to 2009

Groundfish survey data from the German Bight from 1902-08, 1919-23, and 1930-1932 and ICES International Bottom Trawl Survey (IBTS) quarter 3 data from 1991 to 2009 were analysed with respect to species frequencies, maximum length, trends in catch-per-unit-effort, species richness parameters (SNR) and presence of large fish (Phi40), the latter defined as average presence of species per haul with specimens larger than 40 cm given. Four different periods are distinguished: (a) before 1914 with medium commercial CPUE and low landings, Phi40 approx. 2, high abundance in elasmobranchs and SNR conditions indicating highly diverse assemblages, (b) conditions immediately after 1918 with higher commercial CPUE, recovering landings, Phi40 at > 4 in 1919, and SNR conditions indicating highly diverse assemblages, (c) conditions from 1920 to the early 1930's with decreasing commercial CPUE, increased landings, decreasing Phi40, SNR conditions similar to later years indicating less diverse assemblages, and a decrease in elasmobranchs. In the IBTS series (d), Phi40 remains low indicating an increased rarity of large specimens, and SNR characteristics are similar to the third period. Dab, whiting and grey gurnard have increased considerably in the IBTS series as compared to the historic data. Phi40 is suggested an alternative indicator reflecting community functional diversity when weight based indicators cannot be applied.

Seawater carbonate chemistry and cell numbers during experiments with dinoflagellates, 2007

The effects of dissolved inorganic carbon (DIC) on the growth of 3 red-tide dinoflagellates (Ceratium lineatum, Heterocapsa triquetra and Prorocentrum minimum) were studied at pH 8.0 and at higher pH levels, depending upon the pH tolerance of the individual species. The higher pH levels chosen for experiments were 8.55 for C. lineatum and 9.2 for the other 2 species. At pH 8.0, which approximates the pH found in the open sea, the maximum growth in all species was maintained until the total DIC concentration was reduced below ~0.4 and 0.2 mM for C. lineatum and the other 2 species, respectively. Growth compensation points (concentration of inorganic carbon needed for maintenance of cells) were reached at ~0.18 and 0.05 mM DIC for C. lineatum and the other 2 species, respectively. At higher pH levels, maximum growth rates were lower compared to growth at pH 8, even at very high DIC concentrations, indicating a direct pH effect on growth. Moreover, the concentration of bio-available inorganic carbon (CO2 + HCO3-) required for maintenance as well as the half-saturation constants were increased considerably at high pH compared to pH 8.0. Experiments with pH-drift were carried out at initial concentrations of 2.4 and 1.2 mM DIC to test whether pH or DIC was the main limiting factor at a natural range of DIC. Independent of the initial DIC concentrations, growth rates were similar in both incubations until pH had increased considerably. The results of this study demonstrated that growth of the 3 species was mainly limited by pH, while inorganic carbon limitation played a minor role only at very high pH levels and low initial DIC concentrations.