Metabolites from antarctic marine-derived Sporothrix sp. SF-7266

Abstract The Antarctic Treaty System (ATS) is considered a successful example of international governance as it has managed tensions over sovereignty claims, avoided militarisation and dealt with marine resources and environmental protection. Recently, China’s influence and assertiveness in many international institutions have significantly grown. What effect this shift in the international politics will have upon Antarctic governance remains to be seen. However, to further thinking on this issue we explore two current case studies that reveal pressure points within the ATS. First, in the Commission for the Conservation of Antarctic Marine Living Resources, Australia has proposed marine protected areas off East Antarctica, to which China and several other states have objected. Second, in the Antarctic Treaty Consultative Meetings, China has proposed special management arrangements for the area around the “Kunlun” station, to which Australia and several other states have objected. Negotiation theory suggests “logrolling” (i.e. trade of mutual decision-making support across issue areas) can be an effective strategy to avoid diplomatic deadlocks. We therefore consider the merits of a logrolling strategy for the above issues. We find that while a logrolling strategy in the ATS might facilitate short-term diplomatic success, it would carry significant risks, including the weakening of existing norms.

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Ocean acidification of a coastal Antarctic marine microbial community reveals a critical threshold for CO<sub>2</sub> tolerance in phytoplankton productivity

Biogeosciences ◽

10.5194/bg-15-209-2018 ◽

2018 ◽

Vol 15 (1) ◽

pp. 209-231 ◽

Cited By ~ 14

Author(s):

Stacy Deppeler ◽

Katherina Petrou ◽

Kai G. Schulz ◽

Karen Westwood ◽

Imojen Pearce ◽

...

Keyword(s):

Organic Matter ◽

Ocean Acidification ◽

Primary Productivity ◽

Phytoplankton Community ◽

Bacterial Abundance ◽

Critical Threshold ◽

Bacterial Productivity ◽

High Co2 ◽

Chl A ◽

Antarctic Marine

Abstract. High-latitude oceans are anticipated to be some of the first regions affected by ocean acidification. Despite this, the effect of ocean acidification on natural communities of Antarctic marine microbes is still not well understood. In this study we exposed an early spring, coastal marine microbial community in Prydz Bay to CO2 levels ranging from ambient (343 µatm) to 1641 µatm in six 650 L minicosms. Productivity assays were performed to identify whether a CO2 threshold existed that led to a change in primary productivity, bacterial productivity, and the accumulation of chlorophyll a (Chl a) and particulate organic matter (POM) in the minicosms. In addition, photophysiological measurements were performed to identify possible mechanisms driving changes in the phytoplankton community. A critical threshold for tolerance to ocean acidification was identified in the phytoplankton community between 953 and 1140 µatm. CO2 levels ≥ 1140 µatm negatively affected photosynthetic performance and Chl a-normalised primary productivity (csGPP14C), causing significant reductions in gross primary production (GPP14C), Chl a accumulation, nutrient uptake, and POM production. However, there was no effect of CO2 on C : N ratios. Over time, the phytoplankton community acclimated to high CO2 conditions, showing a down-regulation of carbon concentrating mechanisms (CCMs) and likely adjusting other intracellular processes. Bacterial abundance initially increased in CO2 treatments ≥ 953 µatm (days 3–5), yet gross bacterial production (GBP14C) remained unchanged and cell-specific bacterial productivity (csBP14C) was reduced. Towards the end of the experiment, GBP14C and csBP14C markedly increased across all treatments regardless of CO2 availability. This coincided with increased organic matter availability (POC and PON) combined with improved efficiency of carbon uptake. Changes in phytoplankton community production could have negative effects on the Antarctic food web and the biological pump, resulting in negative feedbacks on anthropogenic CO2 uptake. Increases in bacterial abundance under high CO2 conditions may also increase the efficiency of the microbial loop, resulting in increased organic matter remineralisation and further declines in carbon sequestration.

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Spatio-temporal variations in hexachlorobenzene partitioning in a near shore Antarctic marine environment from a one-dimensional coupled ecosystem-chemical distribution model

Journal of Marine Systems ◽

10.1016/j.jmarsys.2019.05.001 ◽

2019 ◽

Vol 196 ◽

pp. 65-76

Author(s):

Michael L Bates ◽

Darryl W Hawker ◽

Roger Cropp

Keyword(s):

Marine Environment ◽

Temporal Variations ◽

Distribution Model ◽

One Dimensional ◽

Antarctic Marine ◽

Near Shore ◽

Spatio Temporal ◽

Chemical Distribution

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Antarctic marine bacterioplankton subpopulations discriminated by their apparent content of nucleic acids differ in their response to ecological factors

Polar Biology ◽

10.1007/s00300-005-0032-2 ◽

2005 ◽

Vol 29 (1) ◽

pp. 27-39 ◽

Cited By ~ 24

Author(s):

A. Corzo ◽

S. Rodríguez-Gálvez ◽

L. Lubian ◽

C. Sobrino ◽

P. Sangrá ◽

...

Keyword(s):

Nucleic Acids ◽

Ecological Factors ◽

Marine Bacterioplankton ◽

Antarctic Marine

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The summer diet of demersal fish at the South Shetland Islands

Antarctic Science ◽

10.1017/s0954102097000527 ◽

1997 ◽

Vol 9 (4) ◽

pp. 407-413 ◽

Cited By ~ 26

Author(s):

Masanori Takahashi ◽

Tetsuo Iwami

Keyword(s):

Marine Ecosystem ◽

Stomach Contents ◽

Demersal Fish ◽

South Shetland Islands ◽

Fish Prey ◽

Shetland Islands ◽

Antarctic Marine ◽

Dietary Component ◽

Gobionotothen Gibberifrons ◽

The Antarctic

The stomach contents of demersal fish in late January 1982 were analysed. Samples were taken at 100, 300 and 500 m depth south of Elephant Island, Bransfield Strait and north of Livingston Island, and at 800 m to the east of Smith Island. Fifty four taxa of fish belonging to 11 families were collected. The diets of 2101 fish representing 38 taxa were examined. These were classified into three categories, fish feeders, krill feeders and benthos feeders. Fish prey species fed on krill and/or benthos. Krill was a major dietary component for 32 (84.2%) out of 38 taxa. Gobionotothen gibberifrons was distributed at all 10 stations (100–800 m in depth) and its diet comprised krill and benthos. The present findings verify the importance of krill in the Antarctic marine ecosystem and indicate that krill is consumed by benthic fish at greater depths than previously reported.

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CCAMLR Conservation Measures: How the Chairman’s Statement Works

The Yearbook of Polar Law Online ◽

10.1163/2211-6427_019 ◽

2015 ◽

Vol 7 (1) ◽

pp. 501-530 ◽

Cited By ~ 1

Author(s):

Denzil G.M. Miller

Keyword(s):

Indian Ocean ◽

State Sovereignty ◽

Review Panel ◽

National Sovereignty ◽

Performance Review ◽

Conservation Measure ◽

Explicit Reference ◽

Antarctic Marine ◽

Indian Ocean Sector ◽

Ocean Sector

The ‘Final Act of the Conference on the Conservation of Antarctic Marine Living Resources’ included a statement made on 19 May 1980 by its Chairman. The ‘Chairman’s Statement’ addressed the CAMLR Convention’s application in waters adjacent to the Kerguelen and Crozet Islands over which France exercises jurisdiction by virtue of its sovereignty over the islands. The Statement included explicit reference to waters adjacent to other islands within the CCAMLR Area, where the existence of State sovereignty is recognised by all the Convention Contracting Parties. In 2007 the CCAMLR Performance Review noted the increasing frequency with which some Commission Members were invoking the Chairman’s Statement. In particular, the Review Panel expressed the view that a point has been reached where any Conservation Measure adopted by CCAMLR invariably attracts a formal reservation on the perception that a conservation measure affects the maritime jurisdictions of certain Members, particularly those exercising national sovereignty over sub-Antarctic islands in the CCAMLR Indian Ocean sector. This paper examines the background to, and practices associated with, applying CCAMLR Conservation Measure reservations under the Chairman’s Statement.

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