Experimental ingestion of microplastics in three common Antarctic benthic species.

Microplastics (MP) have spread to every corner of the globe, reaching remote areas like Antarctica. Recent studies detected MP in marine environments, including biota. Benthic organisms suffer negative effects upon MP ingestion, leading to impacts on their populations.

Diet and debris ingestion of skuas on Fildes Peninsula, King George Island, Antarctica.

Using pellet analysis, we characterized the diet and plastic and non-plastic debris ingestion of skuas (Catharacta spp.) during 2017-2020 summer seasons along the coastal sector of Fildes Peninsula (King George Island, Antarctica). In addition, we conducted the same analysis during the 2020 breeding season on reproductive territories of south polar (Catharacta maccormicki) and brown (Catharacta antarctica lonnbergi) skua.

Stranded pellets in Fildes Peninsula (King George Island, Antarctica): New evidence of Southern Ocean connectivity.

Plastic and microplastic debris is transported by ocean currents over long distances, reaching remote areas, far from its original source. In Polar Regions, microplastics (MPs) can come from local activities or be transported from lower latitudes, with the former being the likely and major source. Although historically Antarctica was considered isolated from the global ocean, there is recent evidence of materials and organisms being transported in and out of the Southern Ocean, despite its multi-front structure.

A reply to "Relevant factors in the eutrophication of the Uruguay River and the Río Negro".

A recent paper by Beretta-Blanco and Carrasco-Letelier (2021) claims that agricultural eutrophication is not one of the main causes for cyanobacterial blooms in rivers and artificial reservoirs. By combining rivers of markedly different hydrological characteristics e.g.

Combining immunolabeling and catalyzed reporter deposition to detect intracellular saxitoxin in a cyanobacterium.

We combined the use of polyclonal antibodies against saxitoxin with catalyzed reporter deposition to detect production of saxitoxin by the cyanobacterium Cylindrospermopsis raciborskii. The procedure is simple, allows detection of intracellular saxitoxin in cyanobacteria filaments by confocal laser microscopy and is a promising tool to study toxin production and metabolism.

Environmental rather than spatial factors structure bacterioplankton communities in shallow lakes along a > 6000 km latitudinal gradient in South America.

Metacommunity studies on lake bacterioplankton indicate the importance of environmental factors in structuring communities. Yet most of these studies cover relatively small spatial scales. We assessed the relative importance of environmental and spatial factors in shaping bacterioplankton communities across a > 6000 km latitudinal range, studying 48 shallow lowland lakes in the tropical, tropicali (isothermal subzone of the tropics) and tundra climate regions of South America using denaturing gradient gel electrophoresis.

Lack of phylogeographic structure in the freshwater cyanobacterium Microcystis aeruginosa suggests global dispersal.

Background: Free-living microorganisms have long been assumed to have ubiquitous distributions with little biogeographic signature because they typically exhibit high dispersal potential and large population sizes. However, molecular data provide contrasting results and it is far from clear to what extent dispersal limitation determines geographic structuring of microbial populations. We aimed to determine biogeographical patterns of the bloom-forming freshwater cyanobacterium Microcystis aeruginosa.