Detecting aquatic pathogens with field-compatible dried qPCR assays.

Field-ready qPCR assays with extended shelf-life support monitoring programs for emerging aquatic pathogens and enable quick conservation and management decisions. Here, we developed, validated, and tested the shelf-life of qPCR assays targeting Gyrodactylus salaris and Aphanomyces astaci with lyophilization and air-drying.

Warming mediates the resistance of aquatic bacteria to invasion during community coalescence.

The immigration history of communities can profoundly affect community composition. For instance, early-arriving species can have a lasting effect on community structure by reducing the invasion success of late-arriving ones through priority effects. This can be particularly important when early-arriving communities coalesce with another community during dispersal (mixing) events.

Functionally reversible impacts of disturbances on lake food webs linked to spatial and seasonal dependencies.

Increasing human impact on the environment is causing drastic changes in disturbance regimes and how they prevail over time. Of increasing relevance is to further our understanding on biological responses to pulse disturbances (short duration) and how they interact with other ongoing press disturbances (constantly present). Because the temporal and spatial contexts of single experiments often limit our ability to generalize results across space and time, we conducted a modularized mesocosm experiment replicated in space (five lakes along a latitudinal gradient in Scandinavia) and time (two seasons, spring and summer) to generate general predictions on how the functioning and composition of multitrophic plankton communities (zoo-, phyto- and bacterioplankton) respond to pulse disturbances acting either in isolation or combined with press disturbances.

Formation of mercury methylation hotspots as a consequence of forestry operations.

Earlier studies have shown that boreal forest logging can increase the concentration and export of methylmercury (MeHg) in stream runoff. Here we test whether forestry operations create soil environments of high MeHg net formation associated with distinct microbial communities. Furthermore, we test the hypothesis that Hg methylation hotspots are more prone to form after stump harvest than stem-only harvest, because of more severe soil compaction and soil disturbance.

Interactions of Freshwater Cyanobacteria with Bacterial Antagonists.

Cyanobacterial and algal mass development, or blooms, have severe effects on freshwater and marine systems around the world. Many of these phototrophs produce a variety of potent toxins, contribute to oxygen depletion, and affect water quality in several ways. Coexisting antagonists, such as cyanolytic bacteria, hold the potential to suppress, or even terminate, such blooms, yet the nature of this interaction is not well studied.

Effects of multiple dimensions of bacterial diversity on functioning, stability and multifunctionality.

Bacteria are essential for many ecosystem services but our understanding of factors controlling their functioning is incomplete. While biodiversity has been identified as an important driver of ecosystem processes in macrobiotic communities, we know much less about bacterial communities. Due to the high diversity of bacterial communities, high functional redundancy is commonly proposed as explanation for a lack of clear effects of diversity.

Microbial community composition and diversity via 16S rRNA gene amplicons: evaluating the illumina platform.

As new sequencing technologies become cheaper and older ones disappear, laboratories switch vendors and platforms. Validating the new setups is a crucial part of conducting rigorous scientific research. Here we report on the reliability and biases of performing bacterial 16S rRNA gene amplicon paired-end sequencing on the MiSeq Illumina platform.

Diversity and abundance of aromatic catabolic genes in lake sediments in response to temperature change.

The abundance and composition of genes involved in the catabolism of aromatic compounds provide important information on the biodegradation potential of organic pollutants and naturally occurring compounds in the environment. We studied catechol 2, 3 dioxygenase (C23O) and benzylsuccinate synthase (bssA) genes coding for key enzymes of aerobic and anaerobic degradation of aromatic compounds in experimental incubations with sediments from two contrasting lakes; humic lake Svarttjärn and eutrophic Vallentunasjön, respectively. Sediment cores from both lakes were incubated continuously for 5 months at constant temperatures ranging from 1.