Climate-driven changes in underwater irradiance and primary productivity in an Antarctic fjord (Potter Cove, Western Antarctic Peninsula).

The West Antarctic Peninsula (WAP) is a hotspot of climate warming, evidencing glacier retreat and a decrease in the fast-ice duration. This study provides a > 30-y time-series (1987-2022) on annual and seasonal air temperatures in Potter Cove (Isla 25 de Mayo/King George Island). It investigates the interaction between warming, glacial melt, fast-ice and the underwater conditions (light, salinity, temperature, turbidity) over a period of 10 years along the fjord axis (2010-2019), and for the first time provides a unique continuous underwater irradiance time series over 5 years (2014-2018).

Potential macroalgal expansion and blue carbon gains with northern Antarctic Peninsula glacial retreat.

The West Antarctic Peninsula (WAP) is a hotspot of physical climate change, especially glacial retreat, particularly in its northern South Shetland Islands (SSI) region. Along coastlines, this process is opening up new ice-free areas, for colonization by a high biodiversity of flora and fauna. At Potter Cove, in the SSI (Isla 25 de Mayo/King George Island), Antarctica, colonization by macroalgae was studied in two newly ice-free areas, a low glacier influence area (LGI), and a high glacier influence area (HGI) differing in the presence of sediment run-off and light penetration, which are driven by levels of glacial influence.

Antarctic Glacial Meltwater Impacts the Diversity of Fungal Parasites Associated With Benthic Diatoms in Shallow Coastal Zones.

Aquatic ecosystems are frequently overlooked as fungal habitats, although there is increasing evidence that their diversity and ecological importance are greater than previously considered. Aquatic fungi are critical and abundant components of nutrient cycling and food web dynamics, e.g.

Icebergs, sea ice, blue carbon and Antarctic climate feedbacks.

Sea ice, including icebergs, has a complex relationship with the carbon held within animals (blue carbon) in the polar regions. Sea-ice losses around West Antarctica's continental shelf generate longer phytoplankton blooms but also make it a hotspot for coastal iceberg disturbance. This matters because in polar regions ice scour limits blue carbon storage ecosystem services, which work as a powerful negative feedback on climate change (less sea ice increases phytoplankton blooms, benthic growth, seabed carbon and sequestration).

Different feeding strategies in Antarctic scavenging amphipods and their implications for colonisation success in times of retreating glaciers.

Background: Scavenger guilds are composed of a variety of species, co-existing in the same habitat and sharing the same niche in the food web. Niche partitioning among them can manifest in different feeding strategies, e.g.

Evidence of macroalgal colonization on newly ice-free areas following glacial retreat in Potter Cove (South Shetland Islands), Antarctica.

Climate warming has been related to glacial retreat along the Western Antarctic Peninsula. Over the last years, a visible melting of Fourcade Glacier (Potter Cove, South Shetland Islands) has exposed newly ice-free hard bottom areas available for benthic colonization. However, ice melting produces a reduction of light penetration due to an increase of sediment input and higher ice impact.

SENSITIVITY OF ANTARCTIC UROSPORA PENICILLIFORMIS (ULOTRICHALES, CHLOROPHYTA) TO ULTRAVIOLET RADIATION IS LIFE-STAGE DEPENDENT(1).

The sensitivity of different life stages of the eulittoral green alga Urospora penicilliformis (Roth) Aresch. to ultraviolet radiation (UVR) was examined in the laboratory. Gametophytic filaments and propagules (zoospores and gametes) released from filaments were separately exposed to different fluence of radiation treatments consisting of PAR (P = 400-700 nm), PAR + ultraviolet A (UVA) (PA, UVA = 320-400 nm), and PAR + UVA + ultraviolet B (UVB) (PAB, UVB = 280-320 nm).