scholarly journals Insights on the environmental impacts associated with visible disturbance of ice-free ground in Antarctica

2019 ◽  
Vol 31 (6) ◽  
pp. 304-314 ◽  
Author(s):  
Shaun T. Brooks ◽  
Pablo Tejedo ◽  
Tanya A. O'Neill

AbstractThe small ice-free areas of Antarctica provide an essential habitat for most evident terrestrial biodiversity, as well as being disproportionately targeted by human activity. Visual detection of disturbance within these environments has become a useful tool for measuring areas affected by human impact, but questions remain as to what environmental consequences such disturbance actually has. To answer such questions, several factors must be considered, including the climate and biotic and abiotic characteristics. Although a body of research has established the consequences of disturbance at given locations, this paper was conceived in order to assess whether their findings could be generalized as a statement across the Antarctic continent. From a review of 31 studies within the Maritime Antarctic, Continental Antarctic and McMurdo Dry Valleys regions, we found that 83% confirmed impacts in areas of visible disturbance. Disturbance was found to modify the physical environment, consequently reducing habitat suitability as well as directly damaging biota. Visible disturbance was also associated with hydrocarbon and heavy metal contamination and non-native species establishment, reflecting the pressures from human activity in these sites. The results add significance to existing footprint measurements based on visual analysis, should aid on-the-ground appreciation of probable impacts in sites of disturbance and benefit environmental assessment processes.

2019 ◽  
Author(s):  
Grant Duffy ◽  
Jasmine R Lee

Warming across ice-covered regions will result in changes to both the physical and climatic environment, revealing new ice-free habitat and new climatically suitable habitats for non-native species establishment. Recent studies have independently quantified each of these aspects in Antarctica, where ice-free areas form crucial habitat for the majority of terrestrial biodiversity. Here we synthesise projections of Antarctic ice-free area expansion, recent spatial predictions of non-native species risk, and the frequency of human activities to quantify how these facets of anthropogenic change may interact now and in the future. Under a high-emissions future climate scenario, over a quarter of ice-free area and over 80 % of the ~14 thousand km2 of newly uncovered ice-free area could be vulnerable to invasion by one or more of the modelled non-native species by the end of the century. Ice-free areas identified as vulnerable to non-native species establishment were significantly closer to human activity than unsuitable areas were. Furthermore, almost half of the new vulnerable ice-free area is within 20 km of a site of current human activity. The Antarctic Peninsula, where human activity is heavily concentrated, will be at particular risk. The implications of this for conservation values of Antarctica and the management efforts required to mitigate against it are in need of urgent consideration.


Polar Record ◽  
1980 ◽  
Vol 20 (126) ◽  
pp. 203-214 ◽  
Author(s):  
Rosamunde J. Reich

The Antarctic continent and its off-lying islands are probably the part of the world least disturbed by man. If all human activity beyond latitude 60°S ceased, all that would remain would be the remnants of scientific stations and a few dilapidated structures associated with Antarctic whaling when it was a land-based industry. Many hold the view that efforts should be made to retain this near-pristine condition and there is therefore widespread opposition to all forms of commercial enterprise in the Antarctic, including tourism. While there may be grounds for opposing the harvesting of living resources because of the possibility of over-exploitation, and for opposing the extraction of Antarctic minerals because of the danger of irreversible environmental damage, opposition to tourism, especially as there are no facilities in the Antarctic specifically designed for their benefit, seems more difficult to justify.


2020 ◽  
Vol 8 (9) ◽  
pp. 1442 ◽  
Author(s):  
Max Ortiz ◽  
Jason Bosch ◽  
Clément Coclet ◽  
Jenny Johnson ◽  
Pedro Lebre ◽  
...  

The Antarctic continent is widely considered to be one of the most hostile biological habitats on Earth. Despite extreme environmental conditions, the ice-free areas of the continent, which constitute some 0.44% of the total continental land area, harbour substantial and diverse communities of macro-organisms and especially microorganisms, particularly in the more “hospitable” maritime regions. In the more extreme non-maritime regions, exemplified by the McMurdo Dry Valleys of South Victoria Land, nutrient cycling and ecosystem servicing processes in soils are largely driven by microbial communities. Nitrogen turnover is a cornerstone of ecosystem servicing. In Antarctic continental soils, specifically those lacking macrophytes, cold-active free-living diazotrophic microorganisms, particularly Cyanobacteria, are keystone taxa. The diazotrophs are complemented by heterotrophic bacterial and archaeal taxa which show the genetic capacity to perform elements of the entire N cycle, including nitrification processes such as the anammox reaction. Here, we review the current literature on nitrogen cycling genes, taxa, processes and rates from studies of Antarctic soils. In particular, we highlight the current gaps in our knowledge of the scale and contribution of these processes in south polar soils as critical data to underpin viable predictions of how such processes may alter under the impacts of future climate change.


2017 ◽  
Vol 29 (4) ◽  
pp. 324-330 ◽  
Author(s):  
Eduardo Fuentes-Lillo ◽  
Marely Cuba-Díaz ◽  
José M. Troncoso-Castro ◽  
Mauricio Rondanelli-Reyes

AbstractThe Antarctic terrestrial ecosystem is relatively simple and has low plant diversity. Taking into account the current effects of climate change and the exponential increase in visitors during the past 50 years, this ecosystem is very vulnerable to the arrival of non-native species. Fildes Peninsula, King George Island, is an area of high human impact due to the scientific and logistical activities that occur there making the area particularly interesting for the arrival of non-native species. In this study, we determine the spectrum of seeds arriving to the peninsula and being deposited in the topsoil. Soil samples were collected and analysed in order to identify and quantify plant material. The results indicate that there is a direct relationship between the sites where seeds were found and areas with higher levels of human activity on the peninsula. Eight species were identified, with the most common beingHypochaeris radicataandSenecio jacobaea. Seed quantification indicated that areas of high human activity are most vulnerable to the invasion and establishment of non-native species. This study is the first to demonstrate the presence of non-native seeds in the topsoil at Fildes Peninsula, Antarctica.


Phytotaxa ◽  
2015 ◽  
Vol 208 (2) ◽  
pp. 103 ◽  
Author(s):  
Tyler J Kohler ◽  
KATEŘINA KOPALOVÁ ◽  
BART VAN DE VIJVER ◽  
J. PATRICK KOCIOLEK

A revision of the freshwater diatom genus Luticola from the McMurdo Sound Region, including the McMurdo Dry Valleys and Cape Royds, Antarctica, was made to contribute to a consistent flora for the entire Antarctic Region. Detailed light and scanning electron microscopic observations, review of pertinent literature, and examination of historical and type material lead to the identification of 12 Luticola species. Four new species and one new combination are proposed, including L. bradyi sp. nov., L. spainiae, sp. nov., L. macknightiae, sp. nov., L. transantarctica, sp. nov., and L. elegans, comb. nov. stat. nov. Several of these taxa were previously identified as part of the L. muticopsis (Van Heurck) D.G.Mann complex; Navicula muticopsis f. evoluta W. & G.S. West, L. muticopsis f. reducta (W. & G.S. West) Spaulding, and N. muticopsis f. capitata Carlson, or mistaken for the similar L. mutica (Kützing) D.G.Mann and L. cohnii (Hilse) D.G.Mann. Morphological features of all new species were compared to the closest morphologically similar taxa, and their ecology and biogeography are discussed. All Luticola species considered here show restricted Antarctic distributions, and 8 of the 12 reported species are known only from the Antarctic continent.


2013 ◽  
Vol 47 ◽  
pp. 167-178 ◽  
Author(s):  
M. P. Andreev

Lichen flora and vegetation in the vicinity of the Russian base «Molodyozhnaya» (Enderby Land, Antarctica) were investigated in 2010–2011 in details for the first time. About 500 specimens were collected in 100 localities in all available ecotopes. The lichen flora is the richest in the region and numbers 39 species (21 genera, 11 families). The studied vegetation is very poor and sparse, but typical for coastal oases of the Antarctic continent. The poorness is caused by the extremely harsh climate conditions, insufficient availability of liquid water, ice-free land, and high insolation levels. The dominant and most common lichens are Rinodina olivaceobrunnea, Amandinea punctata, Candelariella flava, Physcia caesia, Caloplaca tominii, Lecanora expectans, Caloplaca ammiospila, Lecidea cancriformis, Pseudephebe minuscula, Lecidella siplei, Umbilicaria decussata, Buellia frigida, Lecanora fuscobrunnea, Usnea sphacelata, Lepraria and Buellia spp.


Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1551
Author(s):  
Zihuai Guo ◽  
Yibin Yao ◽  
Jian Kong ◽  
Gang Chen ◽  
Chen Zhou ◽  
...  

Global navigation satellite system (GNSS) can provide dual-frequency observation data, which can be used to effectively calculate total electron content (TEC). Numerical studies have utilized GNSS-derived TEC to evaluate the accuracy of ionospheric empirical models, such as the International Reference Ionosphere model (IRI) and the NeQuick model. However, most studies have evaluated vertical TEC rather than slant TEC (STEC), which resulted in the introduction of projection error. Furthermore, since there are few GNSS observation stations available in the Antarctic region and most are concentrated in the Antarctic continent edge, it is difficult to evaluate modeling accuracy within the entire Antarctic range. Considering these problems, in this study, GNSS STEC was calculated using dual-frequency observation data from stations that almost covered the Antarctic continent. By comparison with GNSS STEC, the accuracy of IRI-2016 and NeQuick2 at different latitudes and different solar radiation was evaluated during 2016–2017. The numerical results showed the following. (1) Both IRI-2016 and NeQuick2 underestimated the STEC. Since IRI-2016 utilizes new models to represent the F2-peak height (hmF2) directly, the IRI-2016 STEC is closer to GNSS STEC than NeQuick2. This conclusion was also confirmed by the Constellation Observing System for Meteorology Ionosphere and Climate (COSMIC) occultation data. (2) The differences in STEC of the two models are both normally distributed, and the NeQuick2 STEC is systematically biased as solar radiation increases. (3) The root mean square error (RMSE) of the IRI-2016 STEC is smaller than that of the NeQuick2 model, and the RMSE of the two modeling STEC increases with solar radiation intensity. Since IRI-2016 relies on new hmF2 models, it is more stable than NeQuick2.


1988 ◽  
Vol 6 (3-4) ◽  
pp. 179-184 ◽  
Author(s):  
John A.E. Gibson ◽  
Russell C. Garrick ◽  
Harry R. Burton ◽  
Andrew R. McTaggart

Polar Record ◽  
2013 ◽  
Vol 50 (2) ◽  
pp. 176-182 ◽  
Author(s):  
Łukasz Kaczmarek ◽  
Karel Janko ◽  
Jerzy Smykla ◽  
Łukasz Michalczyk

ABSTRACTIn thirteen (mostly soil) mixed samples, collected from nine localities on the Antarctic continent and some of the neighbouring islands, 788 specimens and 32 eggs of tardigrades were found. In total, five species were identified:Acutuncus antarcticus, Echiniscus jenningsi,Diphascon(D.)victoriae,Hypsibius dujardiniandRamajendas dastychisp. nov.A. antarcticuswas the most abundant (nearly 90% of all specimens) and was the prevailing taxon found in the majority of locations.R. dastychisp. nov. is the fourth species described in the exclusively Antarctic/sub-Antarctic genus. The new species differs from all other congeners by the presence of four gibbosities on the caudo-dorsal cuticle (configuration II:2–2) and also by some morphometric characters. In this paper we also briefly discuss the taxonomy and zoogeography of the genusRamajendas.


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