- Department:(Dept. 3) Plankton and Microbial Ecology
Antarctic glacial meltwater impacts the diversity of fungal parasites associated with benthic diatoms in shallow coastal zones
First study on the fungal diversity in Antarctic benthic habitats along a salinity gradient to determine the co-occurrence of fungal parasites with their algal hosts dominated by benthic diatoms. Ascomycota and Chytridiomycota are the most abundant fungal taxa. Salinity shapes the fungal and the whole eukaryotic community composition, whereby fungal diversity increases with decreasing salinity.
Dissolved organic matter signatures in urban surface waters: spatio-temporal patterns and drivers
The authors studied the dissolved organic matter (DOM) composition from streams, rivers, ponds and lakes within Berlin. They found DOM from lakes and ponds to differ greatly from that of streams and rivers in composition and temporal turnover. Urban land use, nutrient supply and point source pollution were the main drivers of DOM. This suggests including DOM composition in regular monitoring.

Spatial and seasonal patterns of water isotopes in northeastern German lakes
In course of measuring campaigns, the spatial and temporal dynamics of water isotopes in northeastern German lakes were evaluated. The data will serve as basis for further studies, for example with respect to connectivity of lakes and biochemical processes in macrophytes.
Flexible habitat choice of pelagic bacteria increases system stability and energy flow through the microbial loop
The theoretical study evaluated the microbial dynamics of particle-associated vs free-living bacteria. Bacterial generalists have the ability to utilize both habitats and increase stability and energy transport through the 'microbial loop'. Adaptive response strategies of bacteria are important to assess the consequences of increasing particle loads, e.g., sediment and microplastics.
Stoichiometric mismatch causes a warming-induced regime shift in experimental plankton communities
The authors studied effects of warming on spring plankton dynamics in outdoor mesocosms. Experimental warming speeded up phytoplankton growth dramatically, triggering a massive bloom of phosphorus deficient algae that drove its zooplankton grazers to extinction. It shows that warming can aggravate the food quality mismatch at the plant–herbivore interface and limit energy transfer up the food web.
Cross-continental importance of CH4 emissions from dry inland-waters
Despite significant progress in quantifying greenhouse gas emissions from dry inland waters, little is known about methane (CH4). The authors determined CH4 emissions from dry sediments across continents and found that the CH4 contribution ranged from 10 to 21% of the equivalent CO2 emissions. Therefore, CH4 emissions from dry inland waters should be considered for the global carbon cycle.
Land-use type temporarily affects active pond community structure but not gene expression patterns
The team investigated the ffects of land-use type on the composition and gene expression activity of aquatic organisms, using an eRNA approach. At times, there is a temporary difference in the active community structure between ponds in grasslands, forests, and arable fields, but not in the expressed functions. Soon after, the active community returns to being homogenous across the land-use types.
A global agenda for advancing freshwater biodiversity research
Researchers from 90 scientific institutions worldwide have stated that freshwater biodiversity research and conservation lag far behind the efforts in terrestrial and marine environments. They propose a research agenda with 15 priorities aimed at improving research on biodiversity in lakes, rivers, ponds and wetlands. This is urgently needed as the loss of biodiversity there is dramatic.
Recovery of freshwater microbial communities after extreme rain events is mediated by cyclic succession
The authors investigated the resilience of aquatic microbial communities, especially in small ponds, against flooding events. The most interesting result of their high temporal-resolution study was that the microbial communities, in particular bacteria, were surprisingly resilient against flooding events and that bacterial community repeatedly showed a defined path of recovery.
Widespread deoxygenation of temperate lakes
The authors analyzed a combined total of 45,148 dissolved oxygen and temperature profiles and calculate trends for 393 temperate lakes that span 1941 to 2017. They found that a decline in dissolved oxygen is widespread in surface and deep-water habitats. Declines in dissolved oxygen in freshwater are 2.75 to 9.3 times greater than observed in the world’s ocean.