Climate-induced forest dieback drives compositional changes in insect communities that are more pronounced for rare species
Insects declines are now recognised as a consequence of global change. The authors set out to determine the role of drought-induced forest decline in these changes. Using field samples in the Pyrenees and DNA-metabarcoding to determine the species that occur there, they found no loss of species richness in forests experiencing tree loss, but uncovered large differences in the insect communities.
From meta-system theory to the sustainable management of rivers in the Anthropocene
Most existing river conservation, restoration, and biomonitoring practices focus on local-scale strategies and measures. To improve the management of river networks in the Anthropocene, the authors suggest additional metrics and assessment approaches that incorporate regional processes more effectively.
Seasonal differences in the attenuation of polar trace organics in the hyporheic zone of an urban stream
The authors investigated the attenuation of trace organic compounds (TrOCs) at a river influenced by treated wastewater during a sampling campaign in summer and one in winter. Contrary to their expectations, they found higher attenuation for 12 out of 18 TrOCs in winter, while three TrOCs were better attenuated in summer. Sediment conditions varied between seasons.
Disentangling the influence of landscape characteristics, hydroclimatic variability and land management on surface water NO3-N dynamics: spatially distributed modeling over 30 yr in a lowland mixed land use catchment
Our ability to quantify nitrate (NO3-N) fluxes and export at the catchment scale remain limited. The authors used long-term (30 yrs) NO3-N data in a mixed land-use, lowland catchment to investigate the long-term dynamics of hydrological and NO3-N fluxes, and key controlling factors. Landscape characteristics, hydroclimatic variability, and management practices were the dominant drivers for NO3-N.
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.
Experimentally decomposing phytoplankton community change into ecological and evolutionary contributions
The authors experimentally quantified ecological and evolutionary contributions to total phytoplankton community change in response to elevated CO2 concentrations. They show a novel experimental approach to study ecological and evolutionary contributions to community features, and observed a decline in phytoplankton abundance to elevated CO2 that could be mainly explained by ecological changes.
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.
Corrigendum to: The global Microcystis interactome
The authors surveyed the microbiome associated with Microcystis aeruginosa during blooms in 12 lakes. Their results indicate that M. aeruginosa is cosmopolitan in lakes across a 280° longitudinal and 90° latitudinal gradient. The microbiome communities were represented by a wide range of operational taxonomic units and relative abundances which determine the success of the cyanobacteria blooms.
Characterizing the “fungal shunt”: parasitic fungi on diatoms affect carbon flow and bacterial communities in aquatic microbial food webs
The study demonstrates that parasitic fungi profoundly modify microbial interactions through several mechanisms (e.g., stimulating bacterial colonization on phytoplankton cells, altering the community composition of bacteria). Hence, fungal microparasites can substantially shape the microbially mediated carbon flow at the base of aquatic food webs which we termed "fungal shunt" .