List of phytoplankton, zooplankton and zoobenthos species abundances

We studied the effects of changed quality of inflow water of aquaculture ponds on three aquatic communities, phytoplankton, zooplankton and zoobenthos, during two seasons of rearing common carp (Cyprinus carpio). The new water source coming from a deep tube well was markedly different in water chemistry from the surface water sources previously used to maintain the investigated fish ponds. Ponds supplied by the tube well water were characterized by lower oxygen and water hardness, and higher total ammonia and conductivity reaching subsaline conditions. Multivariate analysis (co-inertia) revealed that all investigated groups, except Mollusca (zoobenthos), decreased in species richness, abundance and biomass due to changed water chemistry, but differed in the level of susceptibility to stressors. Assemblages of Rotifera and Cladocera were the most affected showing a sharp decline in density and number of species since 29 out of 44 species disappeared from the ponds. The abundance of Copepoda (Cyclopoida) was relatively high although significantly lower in new environmental conditions (P<0.05), with adults being more tolerant to changed inflow water than larvae. Phytoplankton, except Bacillariophyta, had a highest potential to replace previous species with newcomers more adapted to changed inflow water, providing 36 immigrant species while 49 became extinct. Although mainly influenced by fish predation, Chironomidae (zoobenthos) were undoubtedly affected by changed water chemistry, decreasing from 11 to only 3 species. These results suggest that this pattern was a result of the shift from freshwater to subsaline conditions.

Chlorophyll and true-color maps of sediments from the intertidal zones in Winyah Bay, South Carolina, USA and List, Sylt, Germany

We used hyperspectral imaging to study short-term effects of bioturbation by lugworms (Arenicola marina) on the surficial biomass of microphytobenthos (MPB) in permeable marine sediments. Within days to weeks after the addition of a lugworm to a homogenized and recomposed sediment, the average surficial MPB biomass and its spatial heterogeneity were, respectively, 150 - 250% and 280% higher than in sediments without lugworms. The surficial sediment area impacted by a single medium-sized lugworm (~4 g wet weight) over this time-scale was at least 340 cm**2. While sediment reworking was the primary cause of the increased spatial heterogeneity, experiments with lugworm-mimics together with modeling showed that bioadvective porewater transport from depth to the sediment surface, as induced by the lugworm ventilating its burrow, was the main cause of the increased surficial MPB biomass. Although direct measurements of nutrient fluxes are lacking, our present data show that enhanced advective supply of nutrients from deeper sediment layers induced by faunal ventilation is an important mechanism that fuels high primary productivity at the surface of permeable sediments even though these systems are generally characterized by low standing stocks of nutrients and organic material.

Basic and other measurements of radiation from the Baseline Surface Radiation Network (BSRN) Station Ny-Ålesund in the years 1992 to 2013, reference list of 253 datasets

At Ny-Ålesund (78.9° N), Svalbard, surface radiation measurements of up- and downward short- and longwave radiation are operated since August 1992 in the frame of the Baseline Surface Radiation Network (BSRN), complemented with surface and upper air meteorology since August 1993. The long-term observations are the base for a climatological presentation of the surface radiation data. Over the 21-year observation period, ongoing changes in the Arctic climate system are reflected. Particularly, the observations indicate a strong seasonality of surface warming and related changes in different radiation parameters. The annual mean temperature at Ny-Ålesund has risen by +1.3 ± 0.7 K per decade, with a maximum seasonal increase during the winter months of +3.1 ± 2.6 K per decade. At the same time, winter is also the season with the largest long-term changes in radiation, featuring an increase of +15.6 ± 11.6 W/m**2 per decade in the downward longwave radiation. Furthermore, changes in the reflected solar radiation during the months of snow melt indicate an earlier onset of the warm season by about 1 week compared to the beginning of the observations. The online available dataset of Ny-Ålesund surface radiation measurements provides a valuable data source for the validation of satellite instruments and climate models.