Depth-discrete metagenomics reveals the roles of microbes in biogeochemical cycling in the tropical freshwater Lake Tanganyika
The authors profiled the microbial community in Lake Tanganyika down to a kilometer deep and investigated their role in biogeochemical cycling. The microbial community in the surface waters was not all that different from a temperate lake, the anoxic water contained high abundances of Archaea (30%) and uncultured candidate phyla with high genomic capacity for nitrogen and sulfur cycling.
Safeguarding freshwater life beyond 2020: recommendations for the new global biodiversity framework from the European experience
The year 2020 marked the end of the "UN Decade of Biodiversity". However, the final UN report showed that none of the 20 Aichi-Biodiversity Targets, agreed in 2010, have been achieved. Recognizing the perilous state of freshwater biodiversity, a research team led by IGB has issued 14 recommendations for political follow-up agreements on the protection of biological diversity.
Shallow lakes at risk: nutrient enrichment enhances top‐down control of macrophytes by invasive herbivorous snails
The authors investigated how changing nutrient loading modifies the top‐down effect of one of the worst invasive herbivorous snail species on native submerged macrophytes.The results indicate that snail herbivory may increase the chance for macrophyte collapse and shifts of shallow lakes to turbid states, and that this effect occurs at lower snail densities when nutrient concentrations increase.
Shifting states, shifting services: linking regime shifts to changes in ecosystem services of shallow lakes
The authors identified major shallow lake ecosystem services and their links to Sustainable Development Goals (SDGs), compared service provisioning among the four ecosystem states and discussed potential trade-offs. They identified 39 ecosystem services which are linked to 10 different SDGs, while several trade-offs within and between ecosystem services across ecosystems were identified.
The authors commented on a study (van Klink et al. 2020) on trends in insect biomass and abundance, and argue why they consider the data collected for freshwater to be non-representative and why the results shown there should not be considered indicative of an overall improvement in the condition of freshwater ecosystems.
An international team including Jonathan Jeschke provide the first global quantitative projections of future trajectories of alien species numbers. Based on a new model and assuming a business-as-usual scenario, they project that the number of alien species will increase by 36% until 2050 worldwide and by 64% in Europe.
Size‐selective mortality induces evolutionary changes in group risk‐taking behaviour and the circadian system in a fish
The study addresses the question of whether size-selective fishing can alter the behaviour as well as the chronotype from an evolutionary perspective. Zebrafish adapting to size selection changed their risk-taking behaviour and showed molecular changes in the circadian system, but these were only expressed in subtle adjustments of diurnal behaviour.
Citizen science versus professional data collection: comparison of approaches to mosquito monitoring in Germany
The authors compared 2 approaches to monitor mosquitoes in Germany: professional trapping vs citizen science. They show that these approaches are complementary. While systematically placed traps allow to better map mosquito diversity, the citizen-science approach of the Mückenatlas project allows to easily detect invasive species and provides otherwise unavailable data from private premises.
Stable isotopes of water reveal differences in plant – soil water relationships across northern environments
The authors compared stable isotopes of water in the plant stem (xylem) and in the soil over a complete growing season at five northern experimental sites to understand where plants get their water from and what the temporal dynamics are of such root water uptake. This paper was a main finding of an ERC Grant.
The authors suggest that lunar illuminated fraction should, in general, never be used in biological studies, as alternative variables such as horizontal illuminance better represent moonlight exposure, and therefore offer a greater chance of detecting the effects of moonlight. They provide a brief explanation of how moonlight varies with season and time of night.