Article

Terrestrial Plant Biology of the Sub-Antarctic and Antarctic

Authors:
To read the full-text of this research, you can request a copy directly from the author.

Abstract

Outlines the characteristics of the Antarctic terrestrial biological regions, the origins of the past and present flora, and the history of the present vegetation. Species diversity and taxonomic status of the vascular and cryptogamic flora are reviewed, noting the significance to dispersal of the geographical isolation of the Antarctic, and the cool or cold - though not necessarily short - austral summers, which reduce the potential for survival. Phytogeography and distribution patterns of the vascular and cryptogamic flora are reported, including notes on the alien flora. There are descriptions of the vegetation of 1) the sub-Antarctic islands; tall and short tussock grasslands, meadow, mire, bog, flush, swamp, herbfield, fern-brake and fellfield; 2) maritime and continental Antarctic: crustaceous and foliaceous lichens, fruticose and foliose lichens, short moss cushion and turf, tall moss turf, tall moss cushion, bryophyte carpet, alga-sheet, and grass and cushion chamaephytes. Comments are made on plant community dynamics, especially colonisation and succession, and environmental and morphological pattern and zonation. Phenology, diaspore production, germination, growth, standing crop, production, gas exchange, photosynthate translocation, water relations, decomposition, plant chemistry and survival strategies are all considered at length. -P.J.Jarvis

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the author.

... In Antarctic terrestrial ecosystems, bryophyte communities develop in habitats that receive sufficient liquid water derived from precipitation or snowmelt during the summer months, broadly separating into xeric, mesic and hydric communities (Smith 1984, Wasley et al. 2006. Lacking a vascular system, bryophyte gametophytes do not have the mechanisms available to avoid desiccation, as characterizes vascular plants (Proctor et al. 2007). ...
... Across Antarctica, water availability is recognized as the major driver of terrestrial biodiversity , and the extent of moss communities depends strongly on the availability of liquid water in the summer. In the Maritime Antarctic, these communities range from extensive moss banks and moss carpets that occur in areas with reliable water sources, typically diverse moss and lichen fellfields, and small isolated moss cushions growing in crevices and on rock and soil surfaces (Smith 1984, Ochyra et al. 2008, Block et al. 2009). In the Antarctic Peninsula region, the furthest south published records of bryophyte occurrences are of small cushions of two species from Quilty Nunatak in Ellsworth Land, approaching 76°S (Convey & McInnes 2005). ...
... Therefore, it may be assumed that inter-specific competition between mosses (Grace & Tilman 1990) in Maritime Antarctic habitats such as those of Admiralty Bay is low, meaning that competitive exclusion is improbable. It has previously been noted that Antarctic plant communities do not show features of classical succession processes (Smith 1984, Longton 1988, and, more generally, abiotic constraints are considered to exert far greater influence on biological processes and biodiversity than do biotic features such as competition (Convey 1996, Hogg et al. 2006. ...
Article
Full-text available
We set out to document the diversity and distribution of bryophytes in Admiralty Bay and thereby enable the identification of patterns in local diversity and their possible drivers. Combining data extracted from different sources and recent collections, we documented the presence of 63 species. Similarity analyses of moss species diversity in relation to underlying geology and ornithogenic influence identified an identical cophenetic correlation coefficient of 0.744 for both factors. The Sørensen index was < 0.6, indicating that the groups share < 60% of the species recorded. The data showed that the selected filters (ornithogenic soils, non-ornithogenic soils and different geological extracts) did not underlie consistent species groupings, and we conclude that other environmental and topographical factors are likely to be responsible for shaping the moss community structure in Admiralty Bay. To enable effective management of Antarctic Specially Managed Area (ASMA) No. 1 and Antarctic Specially Protected Area (ASPA) No. 128, robust assessments of the local ecosystem and biodiversity are necessary to assist in the decision-making processes mandated under the Antarctic Treaty System, one of whose founding principles is the preservation of the Antarctic ecosystem.
... Only a few species of flowering plants are able to grow and reproduce in extremely harsh environmental conditions in these regions. In the Maritime (Western) Antarctic area there are two native species of flowering plants -Colobanthus quitensis and Deschampsia antarctica (Lewis Smith 1984;Komárková et al. 1985;Alberdi et al. 2002;Giełwanowska 2005;Parnikoza et al. 2007). Subantarctic flora, due to the milder climate, is characterized by richer vegetation (Lewis Smith 1984;Block 1994). ...
... In the Maritime (Western) Antarctic area there are two native species of flowering plants -Colobanthus quitensis and Deschampsia antarctica (Lewis Smith 1984;Komárková et al. 1985;Alberdi et al. 2002;Giełwanowska 2005;Parnikoza et al. 2007). Subantarctic flora, due to the milder climate, is characterized by richer vegetation (Lewis Smith 1984;Block 1994). There are many species of mosses, liverworts, algae and lichens as well as more species of flowering plants ( Rakusa-Suszczewski et al. 1998;Alberdi et al. 2002;Rakusa-Suszczewski 2012), including Colobanthus apetalus which became the object of the current study. ...
... Very good example for this strategy could be Deschampsia antarctica, which reproduces mainly by stolons (Parnikoza et al. 2012). However, there are reports that Antarctic plants reproduce also generatively and undergo a full development cycle, which leads to viable seeds formation (Lewis Smith 1984;Convey 1996;Zúñiga et al. 1996). According to King (1994), Kellmann-Sopyła et al. (2011) andCavieres et al. (2016) intensive climate change, primarily warming, which is observed over the past few decades, are beneficial for generative reproduction and is likely to favor this phenomenon. ...
Article
Full-text available
This study investigated the details of the morphological and anatomical structure of the generative organs of the Subantarctic flowering plant, belonging to the family Caryophyllaceae-Colobanthus apetalus (Labill.) Druce. The research material was collected in hostile natural conditions in Subantarctic regions, and also was grown in the incubators and the greenhouse of the University of Warmia and Mazury in Olsztyn (Poland). C. apetalus forms tufts with soft and grassy leaves and small greenish flowers that are more obvious than in other Colobanthus species. C. apetalus forms open (chasmogamic) flowers in greenhouse cultivation. The flowers most often form five stamens with two microsporangia. Over a dozen pollen grains are formed in each microsporangium. Studies of the plant material originated from natural conditions conducted by means of a light microscope, have shown that the ovules of the analyzed representative of the genus Colobanthus are anatropous, crassinucellar, and the monosporic embryo sac develops according to the Polygonum type (the most common type in angiosperms). C. apetalus plants underwent a full development cycle in greenhouse cultivation and produced fertile, perispermic seeds. During the C. apetalus growth in conditions at increased air humidity, the vivipary was also observed.
... De plus, une hétérogénéité du climat à l'échelle locale et régionale est observable . Par ailleurs, les régions subantarctique et antarctique côtières ont une température du sol fréquemment supérieure à 0°C sans pergélisol contrairement à l'Antarctique continental (Smith 1984;. Ces différents milieux alpins, polaires et subpolaires présentent des fellfields qui sont définis vigueur de la plante . ...
... Le paysage des îles Kerguelen est vallonné et est composé de plusieurs types d'habitats, tels que les fellfields (Smith 1984). Le climat des îles Kerguelen est froid avec une température annuelle moyenne de 4,6°C et des précipitations annuelles moyennes de 755 mm à "Port aux Français" de 1951 à 2018 . ...
... Latitudes impact temperatures, solar irradiances and seasonal and diurnal patterns that induce differences between alpine (temperate and equatorial), sub-polar and polar regions . In sub-polar and coastal regions, the soil is not composed of permafrost and soil temperature is buffered and above 0°C (Smith 1984;. ...
Thesis
The adaptive capacity of plants to climate change is defined as the ability of a species or population to cope with new environmental conditions and persist in surviving and reproducing. The Kerguelen Islands, in the sub-Antarctic region, harbour the long-lived endemic species, Lyallia kerguelensis Hook.f. (Montiaceae). The plant's distribution is restricted to the Island fellfields, regarded as a form of tundra ecosystem of rock with cold climate and strong winds. The plant might seem ill-equipped to face drastic climate change. Its strict endemism, relatively scarce distribution, cushion form and the occurrence of necrosis led to questioning its adaptive capacity. We hypothesized that the pool of variability (of morphology, transcriptome and soil rhizomicrobiome) of L. kerguelensis across contrasted environments might provide insights into its adaptation to harsh environments and its possible response to rapid climate change. In addition, we used data from long-term monitoring of the fate of populations and their morphological dynamics. L. kerguelensis’ morphology reveals allometry and responses to soil water content and wind intensity. Its transcriptome is region-specific with differential expression of genes related to abiotic or biotic stress responses. The microbiome of the Kerguelen Islands’ fellfield soils is specific and varies in relation to the soil nutrient content, and the rhizomicrobiome shows a similar variation while its composition is under the influence of the plant. Necrosis might be drought stress damages strongly related to fast drying and warming climate and might be worsened by salt stress and a shift in rhizomicrobiome composition. Finally, L. kerguelensis growth is very slow and population-specific and its life span is estimated at least several decades. Under current climate change trends in the Kerguelen Islands, L. kerguelensis may have the capacity to cope and change to adjust to environmental variation to a certain extent.
... There is no generally accepted system of biogeographic subdivision. Several biogeographical schemes A c c e p t e d M a n u s c r i p t have been proposed to divide the Antarctic region into biological areas based on a combination of biotic and climatic characteristics: Skottsberg 1945Skottsberg , 1960Wace 1960Wace , 1965Alexandrova 1977Alexandrova , 1980Greene 1967;Holdgate 1964Holdgate , 1970Markov et al. 1970;Korotkevich 1966;Longton 1967Longton , 1973Longton , 1979Moore 1968;Bliss 1979;Pickard and Seppelt 1984;Lewis Smith 1984;Bednarek-Ochyra et al. 2000;Convey 2006 or Peat et al., among others. Terrestrial biologists have traditionally divided the Antarctic region into three biogeographic zones: Continental Antarctic, Maritime Antarctic and Subantarctic (Chown and Convey 2006). ...
... Several authors have also proposed subdivisions in these regions (Skottsberg 1960, Bugaev 1960, Korotkevich 1966, Pickard and Seppelt 1984, Lewis Smith 1984, Bednarek-Ochyra et al. 2000. Lewis Smith (1984) and Bednarek-Ochyra et al. (2000) divided the Maritime Antarctic region into two provinces (Northern and Southern provinces), and the Continental Antarctic into Coastal and Slope provinces. ...
... Several authors have also proposed subdivisions in these regions (Skottsberg 1960, Bugaev 1960, Korotkevich 1966, Pickard and Seppelt 1984, Lewis Smith 1984, Bednarek-Ochyra et al. 2000. Lewis Smith (1984) and Bednarek-Ochyra et al. (2000) divided the Maritime Antarctic region into two provinces (Northern and Southern provinces), and the Continental Antarctic into Coastal and Slope provinces. More recently, Peat et al. (2007) proposed a phytogeographic division of Antarctica into three provinces: Northern and Southern provinces in the Maritime Antarctic Region, and the Continental province in the Continental Antarctic Region. ...
Article
This study proposes a bioclimatic characterization and a new biogeographic division for the Antarctic territories up to the province level following the criteria and models of Rivas-Martínez et al. The Antarctic Kingdom comprises the continent of Antarctica, the surrounding ice-covered Antarctic islands, and the associated cold oceanic islands and archipelagos. It has two biogeographic regions: the Antarctic Region and the Subantarctic Insular Region. The Antarctic Region includes the entire pergelid Antarctic continent and the surrounding islands and archipelagos, and is characterized by upper suprapolar hyperoceanic and oceanic or Polar pergelid bioclimates on the coasts. The region has been divided into three pr6ovinces: Maritime Antarctica, West Antarctica and East Antarctica. The Subantarctic Insular Region comprises the circumantarctic islands and archipelagos that are widespread at the southern tip of the planet’s most important oceans, mostly in the subtemperate latitudinal zone inside or not far from the Antarctic Convergence. Bioclimatically, all insular subantarctic territories (excluding the South-American Tierra de Fuego, Terra Magellanica and large islands) are characterized by thermo-suprapolar and semipolar antarctic hyperoceanic bioclimates on the coasts. Four provinces – Falklandian-South Georgian, Kerguelenian, Macquarian and Aucklandian-Campbellian – have been recognized in this region. All these units are characterized by floristic bioindicators.
... In common with most scientific effort on the continent, terrestrial biological research commenced in earnest in the 1960s, although scientific collections had been an important element of most of the exploring expeditions from the early 20th century. Over most of the subsequent 50-60 years, three Antarctic biogeographic zones were generally recognized, the sub-, maritime, and continental Antarctic (e.g., Smith, 1984). Respectively, these zones include (a) a ring of chronically cool, remote and isolated islands at mid to high latitude in the Southern Ocean (ca. ...
... There are also no insect-pollinated plant species (with a similar lack of insect pollinators). Smith (1984) provides an accessible and thorough overview of Antarctic floras, although there have been subsequent advances in taxonomy. Monographs of the Antarctic lichen (Øvstedal and Smith, 2001) and bryophyte (Ochyra et al., 2008) floras are available. ...
... Maritime Antarctic floras are dominated by cryptogams (bryophytes, lichens, algae) (Smith, 1984). Extensive areas of vegetation, consisting of communities of carpet-and turf-forming mosses, are exclusively coastal and low altitude. ...
Chapter
Antarctica's contemporary terrestrial biota have adapted to the continent's environmental challenges over many millions of years. It now faces the twin challenges of the multiple aspects of global and regional environmental change and the direct impacts of human presence and activity. Most native terrestrial biota possess wide physiological and ecological flexibility, well beyond the expected scale of environmental change over the next century and, when considered in isolation, are likely to show positive responses to environmental ameliorations, particularly the combination of increased thermal energy and liquid water availability, through increased production, populations, local distribution extent, and community complexity. However, over this timescale other, direct, human impacts on Antarctic terrestrial ecosystems and biodiversity are likely to have greater and negative consequences. Major sources of such impacts are likely to come through physical damage to the limited available area of terrestrial habitats, and the anthropogenic introduction of non-native species, a proportion of which are likely to become invasive and act as ecosystem engineers.
... Three main Antarctic regions with contrasting environmental conditions have been traditionally recognized in the literature: Continental Antarctica, Maritime Antarctica and Sub-Antarctic islands and archipelagos (e.g., Smith, 1984). Generally, the climate of Continental Antarctica can be regarded as more severe than those of the Maritime and sub-Antarctic zones (Smith, 1984;Convey, 2001;Chown & Convey, 2006;Gibson et al., 2006). ...
... Three main Antarctic regions with contrasting environmental conditions have been traditionally recognized in the literature: Continental Antarctica, Maritime Antarctica and Sub-Antarctic islands and archipelagos (e.g., Smith, 1984). Generally, the climate of Continental Antarctica can be regarded as more severe than those of the Maritime and sub-Antarctic zones (Smith, 1984;Convey, 2001;Chown & Convey, 2006;Gibson et al., 2006). The Maritime Antarctic and sub-Antarctic regions are characterized by higher mean temperatures and precipitation than the continental one (e.g., Convey, 2013). ...
Article
Full-text available
Antarctica holds a great number of inland lakes whose characteristics vary from ultra-oligotrophic to hypereutrophic, and from freshwater to hypersaline. The harsh conditions in these ecosystems (extremely low temperatures, large annual variation in solar radiation, light limitation below the ice) account for adaptive strategies of the selected phytoplankton species; some of them are mixotrophy, formation of resistant cysts, starch accumulation, pigment adaptation and motility. Algal richness is comparatively lower than in other parts of the world, although molecular studies are now revealing a biodiversity much higher than that previously based on morphological identifications. Many lakes are permanently stratified, such as perennially ice-covered or saline meromictic, whereas shallow lakes in coastal regions are usually ice-free in summer, accounting for contrasting patterns in their phytoplankton temporal dynamics. Simple and short food webs are characteristic of Antarctic lakes, where phytoplankton fraction > 2 μm is usually dominated by nanoflagellates. In this review, we provide an overview of the current knowledge about phytoplankton of Antarctic lakes, including information on biodiversity (morphological-based, functional and molecular), and the main ecological aspects (colonization, endemism, ecological strategies, temporal dynamics, biotic interactions). We compared ecosystems of different trophic status and from Continental and Maritime Antarctica, including own data from manipulative experiments.
... Long-term work has demonstrated how quickly vegetative communities can change in response to glacial retreat (Smith, 1984;Frenot et al., 1995;Olech, 2010;Olech & Massalski, 2001;. Pioneer colonizers in the fellfields of retreating glaciers included the mosses Bryum pseudotriquetrum, B. argenteum and C. purpureus, alongside the two vascular plants D. antarctica and C. quitensis. ...
... Pioneer colonizers in the fellfields of retreating glaciers included the mosses Bryum pseudotriquetrum, B. argenteum and C. purpureus, alongside the two vascular plants D. antarctica and C. quitensis. Lichens generally follow in subsequent stages of succession (Olech, 2010;Smith, 1984), though Usnea antarctica has been noted rapidly colonizing boulders (Lindsay, 1971). In contrast, some water-loving species declined over time or vanished completely, in particular the mosses Warnstorfia sarmentosa and Brachythecium austrosalebrosum, several lichens including Leptogium puberulum and Polyblastia gothica, and ascomycota fungi Octospora arctowski. ...
Article
Full-text available
Antarctic biodiversity faces an unknown future with a changing climate. Most terrestrial biota is restricted to limited patches of ice‐free land in a sea of ice, where they are adapted to the continent’s extreme cold and wind and exploit microhabitats of suitable conditions. As temperatures rise, ice‐free areas are predicted to expand, more rapidly in some areas than others. There is high uncertainty as to how species’ distributions, physiology, abundance and survivorship will be affected as their habitats transform. Here we use current knowledge to propose hypotheses that ice‐free area expansion i) will increase habitat availability, though the quality of habitat will vary; ii) will increase structural connectivity, although not necessarily increase opportunities for species establishment; iii) combined with milder climates will increase likelihood of non‐native species establishment, but may also lengthen activity windows for all species; and iv) will benefit some species and not others, possibly resulting in increased homogeneity of biodiversity. We anticipate considerable spatial, temporal, and taxonomic variation in species responses, and a heightened need for interdisciplinary research to understand the factors associated with ecosystem resilience under future scenarios. Such research will help identify at‐risk species or vulnerable localities and is crucial for informing environmental management and policymaking into the future.
... The cool and cold areas in the Southern Hemisphere centered on the South Pole consist of the largely ice-covered Antarctic continent and a number of small and highly isolated islands or groups of islands widely scattered in the vast Southern Ocean. The delimitation and subdivision of the austral polar regions have been the subject of much discussion and controversy [1]. Subdivision of this region into at least two distinct biomes is now generally accepted. ...
... The South Sandwich Islands archipelago in the Scotia Arc and the orphaned Bouvetøya in the South Atlantic Ocean, both of which lie a little north of lat. 60°S, are also included to the Antarctic biome because of their similar climate and terrestrial vegetation [1]. The northern limit of the Antarctic biome is delimited by the Antarctic Convergence or Polar Frontal Zone, a seasonally varying oceanic boundary encircling Antarctica, where cold northward-flowing Antarctic waters meet and sink below the relatively warmer waters of the Subantarctic. ...
Article
Full-text available
Studies on the bryophyte flora of the Southern Ocean islands and in the Antarctic are briefly reviewed and the current state of knowledge of the moss flora of Îles Kerguelen is discussed. Macrocoma tenue (Hook. & Grev.) Vitt is recorded from the Îles Kerguelen archipelago and this constitutes the first record of the genus Macrocoma (Müll. Hal.) Grout from the Subantarctic. The local plants of the species are characterized and illustrated and their ecology is discussed. Global distribution of M. tenue is reviewed and mapped. It is suggested that the type subspecies of M. tenue is a Gondwanan relictual taxon, which could have evolved on this supercontinent prior to its break-up and, subsequently, it reached Îles Kerguelen where it survived during the Pleistocene glacial epoch.
... The combination of remoteness, small area, glaciation and severe climate has also resulted in reduced range of vegetation types in comparison to subantarctic islands north of the APFZ. Marion Island (46°9'S, 36°75'E) is an appropriate comparison, being of volcanic origin, with both moraines and post-glacial volcanics, a small relectual ice cap and related floras and faunas (see Lewis Smith, 1984;Chown, 1994). As a result of being south of the APFZ, the more severe climate of Heard Island means that altitudinal range in which substantial vegetation is found is less (sea level to approximately 250 m) than on Marion Island (sea level to 650-700 m) (Gremmen, 1981). ...
Article
Full-text available
The vascular and bryophyte floras of subantarctic Heard Island were classified using cluster analysis into six vegetation communities: Open Cushion Carpet, Mossy Feldmark, Wet Mixed Herbfield, Coastal Biotic Vegetation, Saltspray Vegetation, and Closed Cushion Carpet. Multidimensional scaling indicated that the vegetation communities were not well delineated but were continua. Discriminant analysis and a classification tree identified altitude, wind, peat depth, bryophyte cover and extent of bare ground, and particle size as discriminating variables. The combination of small area, glaciation, and harsh climate has resulted in reduced vegetation variety in comparison to those subantarctic islands north of the Antarctic Polar Front Zone. Some of the functional groups and vegetation communities found on warmer subantarctic islands are not present on Heard Island, notably ferns and sedges and fernbrakes and extensive mires, respectively.
... However, morphological plasticity is not accompanied by equally extensive genetic variability, which is generally low in the entire species range. A discrete decrease in genetic diversity is observed from the north to the south, with minimum values in the area of the Antarctic Peninsula(Holderegger et al., 2003;Chwedorzewska & Bednarek, 2008; van de Wouw et al., 2008).According to the literature, D. antarctica colonized Antarctica during the Holocene(Chapman, 1996;Lewis-Smith, 1984). In the paleobotanical research conducted byBirkenmajer et al. (1985), the fragments and pollen of D. antarctica isolated from peat cores were dated back at least five millennia. ...
Article
Full-text available
Deschampsia antarctica Desv. can be found in diverse Antarctic habitats which may vary considerably in terms of environmental conditions and soil properties. As a result , the species is characterized by wide ecotypic variation in terms of both morphological and anatomical traits. The species is a unique example of an organism that can successfully colonize inhospitable regions due to its phenomenal ability to adapt to both the local mosaic of microhabitats and to general climatic fluctuations. For this reason, D. antarctica has been widely investigated in studies analyzing morphophysiological and biochemical responses to various abiotic stresses (frost, drought, salinity, increased UV radiation). However, there is little evidence to indicate whether the observed polymorphism is accompanied by the corresponding genetic variation. In the present study, retrotransposon-based iPBS markers were used to trace the genetic variation of D. antarctica collected in nine sites of the Arctowski oasis on King George Island (Western Antarctic). The genotyping of 165 individuals from nine populations with seven iPBS primers revealed 125 amplification products, 15 of which (12%) were polymorphic, with an average of 5.6% polymorphic fragments per population. Only one of the polymorphic fragments, observed in population 6, was represented as a private band. The analyzed specimens were characterized by low genetic diversity (uH e = 0.021, I = 0.030) and high population differentiation (F ST = 0.4874). An analysis of Fu's FS statistics and mismatch distribution in most populations (excluding population 2, 6 and 9) revealed demographic/spatial expansion, whereas significant traces of reduction in effective population size were found in three populations (1, 3 and 5). The iPBS markers revealed genetic polymorphism of D. antarctica, which could be attributed to the mobilization of random transposable elements, unique features of reproductive biology, and/or geographic location of the examined populations.
... Vegetation is patchy, mainly composed of lichens and bryophytes (Smith 1984;Block et al. 2009). ...
Article
Full-text available
In recent decades, climate change has been faster in various parts of the world. Within species, to counter rapid climate changes shift of geographical area, individuals’ plastic responses or populations’ genetic adaptation might occur. The sub-Antarctic islands are subject to one of the most rapid climate changes on earth, with already visible impacts on native vegetation. Such might be the case of Lyallia kerguelensis a cushion plant strictly endemic to the Kerguelen Islands. In L. kerguelensis, necrotic parts were observed in cushions these last decades and possibly related to water stress. We analysed morphological variability of L. kerguelensis, including necrosis extent, across 19 populations spanning a wide range of environments across the Kerguelen Islands. Inter-population variations in the cushion surface area, shape and compactness were well explained by topography, degree of wind exposure, slope aspect, proportions of coarse sand and bare soil, and geographical distance between populations. All these variables are related to wind intensity and water availability. Moreover, in cushions with less than 10% necrosis in surface area, necrosis extent was positively correlated to soil sodium. Sodium availability might reduce the plant’s capacity for osmotic adjustment in face of other abiotic stresses, such as water stress. We conclude that cushion morphology may have the capacity to adjust to environmental variation, including aspects of climate change, but that cushion necrosis may be accelerated in the driest and most saline environments.
... Lyallia kerguelensis and Ranunculus moseleyi are strictly endemic to Kerguelen (Hennion and Walton 1997;Lehnebach et al. 2017). Colobanthus kerguelensis, Poa cookii, Poa kerguelensis and Pringlea antiscorbutica are endemic to the South Indian Ocean Province (SIOP) that includes Kerguelen, Marion and Prince Edward Islands, Crozet, and Heard (Smith 1984;Van der Putten et al. 2010). Except for Limosella australis, at least three populations per species were studied. ...
Article
Full-text available
Kerguelen Islands harbor a unique, probably very ancient flora with a high rate of endemism. However, the evolutionary history and characteristics of this flora still require investigation. This concerns in particular genome size and ploidy level variation, despite the evolutionary and ecological significance of those traits. Here we report the first assessment of genome size, using flow cytometry, for eight plant species of which two are endemics of Kerguelen Islands and four of the South Indian Ocean Province. The 2C DNA value ranged from 1.08 pg for Pringlea antiscorbutica to 11.88 pg for Ranunculus biternatus. The chromosome numbers of Colobanthus kerguelensis (2n = 80), Lyallia kerguelensis (2n = 96) and Poa kerguelensis (2n = 28) were also reported in this study for the first time. Overall, our data allowed to infer that all Kerguelen studied species are polyploid (from tetra- to octopolyploid). Intra-genus comparisons showed significant differences of 2C DNA values among Poa and among Ranunculus species, despite their identical ploidy level. In addition, our data highlight the existence of an intraspecific variability of genome size for the two octoploid species Colobanthus kerguelensis and Lyallia kerguelensis. Finally, our data also support the hypothesis regarding which polyploidy may have played a major role in the adaptation of flowering plants to high latitudes, as it has been suggested for arctic species.
... Precipitation is difficult to measure in Antarctica (Turner et al., 1995), but data from several sources indicate that there is an increase in MAP of > 1000 mm ac.uk/project/meteorology-and-ozone-monitoring/) and the Regional Atmospheric Climate Model of Van Lipzig et al. (1999), as reported by Newsham et al. (2016). Mean annual precipitation (MAP) data are from Smith and Walton (1975), Smith (1984) and Turner et al. (2002). between L� eonie Island and Bird Island (Fig. 1a). ...
Article
Full-text available
We report a space-for-time substitution study predicting the impacts of climate change on vegetated maritime Antarctic soils. Analyses of soils from under Deschampsia antarctica sampled from three islands along a 2200 km climatic gradient indicated that those from sub-Antarctica had higher moisture, organic matter and carbon (C) concentrations, more depleted δ¹³C values, lower concentrations of the fungal biomarker ergosterol and higher concentrations of bacterial PLFA biomarkers and plant wax n-alkane biomarkers than those from maritime Antarctica. Shallow soils (2 cm depth) were wetter, and had higher concentrations of organic matter, ergosterol and bacterial PLFAs, than deeper soils (4 cm and 8 cm depths). Correlative analyses indicated that factors associated with climate change (increased soil moisture, C and organic matter concentrations, and depleted δ¹³C contents) are likely to give rise to increases in Gram negative bacteria, and decreases in Gram positive bacteria and fungi, in maritime Antarctic soils. Bomb-¹⁴C analyses indicated that sub-Antarctic soils at all depths contained significant amounts of modern ¹⁴C (C fixed from the atmosphere post c. 1955), whereas modern ¹⁴C was restricted to depths of 2 cm and 4 cm in maritime Antarctica. The oldest C (c. 1745 years BP) was present in the southernmost soil. The higher nitrogen (N) concentrations and δ¹⁵N values recorded in the southernmost soil were attributed to N inputs from bird guano. Based on these analyses, we conclude that 5–8 °C rises in air temperature, together with associated increases in precipitation, are likely to have substantial impacts on maritime Antarctic soils, but that, at the rates of climate warming predicted under moderate greenhouse gas emission scenarios, these impacts are likely to take at least a century to manifest themselves.
... Aufgrund des harschen Klimas und des Mangels an organischem Material kommt es nur in geringem Umfang zur Bodenbildung. Zudem gelten Böden in der Antarktis grundsätzlich als nährstoffarm (Lewis-Smith, 1984). Pflanzen besiedeln felsige Hänge, Moränen und kaum entwickelte Böden (z. ...
... Proper conservation planning and management of the Antarctic is urgent for protecting its often endemic biota (Convey et al. 2014(Convey et al. , 2020 as most of them have narrow distributional ranges due to the long-term survival of taxa in isolated glacial refugia during ice ages , Fraser et al. 2014, Biersma et al. 2018). In the sub-Antarctic, isolation has long been thought to underpin patterns in its terrestrial biodiversity leading to three distinct provinces (Smith 1984), namely the South Atlantic, South Indian and South Pacific Provinces. Recent molecular studies of sub-Antarctic terrestrial plants and invertebrates have partly challenged this view and revealed that many organisms showed occasional historic long distance dispersal events, but that ongoing gene flow across the region is rare (McGaughran et al. 2019, see Moon et al. 2017 for a review). ...
Article
Full-text available
Terrestrial biota in the Antarctic are more globally distinct and highly structured biogeographically than previously believed, but information on biogeographic patterns and endemism in freshwater communities is largely lacking. We studied biogeographic patterns of Antarctic freshwater diatoms based on the analysis of species occurrences in a dataset of 439 lakes spread across the Antarctic realm. Highly distinct diatom floras, both in terms of composition and richness, characterize Continental Antarctica, Maritime Antarctica and the sub‐Antarctic islands, with marked biogeographic provincialism in each region. A total of 44% of all species is estimated to be endemic to the Antarctic, and most of them are confined to a single biogeographic region. The level of endemism significantly increases with increasing latitude and geographic isolation. Our results have implications for conservation planning, and suggest that successful dispersal of freshwater diatoms to and within the Antarctic is limited, fostering the evolution of highly endemic diatom floras.
... The southwestern margin of the bay is characterized by the presence of many bodies of water, mostly of glacial origin and some are subject to natural eutrophication due to the presence of a large Pygoscelis adelia penguin rookery. HB is characterized by a cold moist maritime climate (Lewis Smith, 1984). ...
Article
Climate change has contributed to the regional retreat and melting of glaciers in the Antarctic Peninsula. This phenomenon is expected to affect the composition of plankton communities. The aim of this study is to analyze the influence of glacier melting on the composition and structure of phytoplankton and micro- and mesozooplankton assemblages in two coastal areas located in the northwest (Potter Cove) and in the northern end (Hope Bay) of the Antarctic Peninsula during summer 2013. We expect differences in plankton assemblages between PC and HB related to the fact that these areas are subjected to different climatic and environmental conditions and that the glacier meltwater is accumulated in lakes in HB whereas the meltwater directly reaches the adjacent sea at PC. However, plankton communities differed according to their proximity to the glaciers in both areas investigated, with a transition from herbivorous to microbial plankton food webs towards the glacier. The microbial food web was favored under the effects of glacier meltwater due to the stratification of the water column that favors the development of small eukaryotic algae. These are potential prey for ciliates and heterotrophic dinoflagellates favors the development of small omnivorous copepods. Further away from the glaciers, the herbivorous food web consists of large phytoplankton and a greater representation of herbivorous mesozooplankton organisms. It can be inferred from this study that increases in atmospheric temperatures may favor the development of microbial plankton food webs in the Antarctic coastal seas during summer due to increased glacier meltwater.
... Vegetation communities on the island have been described by Taylor (1955a), Smith (1984) and Williams et al. (2016) and consist largely of tussock grasses and tall and short herb vegetation on lower elevation coastal slopes. Above an elevation of approximately 200 m, "feldmark" vegetation communities dominate. ...
Article
We examined the nature and properties of soils on Australian sub-Antarctic Macquarie Island to determine key environmental factors driving their distribution, development and change. We provide the first classification of these soils using Australian and international (WRB) systems while combining elemental, stable and radio-isotope analysis to interpret processes of soil formation and key controlling environmental factors. Soil organic carbon (SOC) and total nitrogen (TN) concentrations across the island were influenced largely by elevation and topographic position with coastal soils and wetter depressions containing more SOC and TN compared with drier and higher elevation locations. Soils on the high, exposed plateau of the island contained low SOC and TN concentrations by comparison. Results suggested that soils of the coastal zone are subject to ongoing aggradation with significant inputs of nutrient, particularly extractable P (Ext P), from oceanic and especially avifauna sources. Nutrient subsidy was concentrated on coastal margins and the more sheltered eastern side of the island, diminishing significantly with increasing elevation and distance from the coast. Soils of the central plateau contained very low Ext P concentrations throughout the profile and appear to be relic if not degrading. Further comprehensive soil mapping, classification and monitoring across Macquarie Island will elucidate the important role that soils serve for healthy ecosystem function in these sub-Antarctic environments and provide early warning indicators of significant environmental change.
... The warmest ACBRs were ACBRs 1, 2 and 3, which are located on the Antarctic Peninsula or Scotia Arc, and all three example stations had mean summer temperatures greater than 0°C. This result fits with the earlier classification that defines the area encompassed by ACBRs 1, 2 and 3 as the Maritime Antarctic region, as compared to the rest of the Antarctic ice-free areas, which are referred to as the Continental Antarctic region (Smith, 1984). In turn, continental ACBRs generally experienced lower mean temperatures than ACBRs 1, 2, and 3 ( Fig. 3). ...
Article
The distribution of terrestrial biodiversity within Antarctica is complex, with 16 distinct biogeographic regions (Antarctic Conservation Biogeographic Regions) currently recognised within the Antarctic continent, Peninsula and Scotia Arc archipelagos of the Antarctic Treaty area. Much of this diversity is endemic not only to Antarctica as a whole, but to specific regions within it. Further complexity is added by inclusion of the biodiversity found on the islands located in the Southern Ocean north of the Treaty area. Within Antarctica, scientific, logistic and tourism activities may inadvertently move organisms over potentially long distances, far beyond natural dispersal ranges. Such translocation can disrupt natural species distribution patterns and biogeography through: (1) movement of spatially restricted indigenous species to other areas of Antarctica; (2) movement of distinct populations of more generally distributed species from one area of Antarctica to another, leading to genetic homogenisation and loss of assumed local patterns of adaptation; and (3) further dispersal of introduced non-native species from one area of Antarctica to another. Species can be moved between regions in association with people and cargo, by ship, aircraft and overland travel. Movement of cargo and personnel by ship between stations located in different biogeographic regions is likely to present one of the greatest risks, particularly as coastal stations may experience similar climatic conditions, making establishment more likely. Recognising that reducing the risk of inter-regional transfer of species is a priority issue for the Antarctic Treaty Consultative Meeting, we make practical recommendations aimed at reducing this risk, including the implementation of appropriate biosecurity procedures.
... On the basis of climatic and biotic features, the austral polar region is subdivided into three zones, including the sub-Antarctic, maritime Antarctic, and continental Antarctic [1]. The South Shetlands Islands belong to the maritime Antarctic, together with the South Orkney Islands, the South Sandwich Islands, Bouvetoya, and the west ...
Article
Full-text available
This paper contributes 96 species to the biota of lichenicolous fungi in the South Shetland Islands archipelago. New to science are the following genera: Antarctosphaeria Alstrup & Olech, gen. nov., Dahawkswia Alstrup & Olech, gen. nov., Lichenohostes Alstrup & Olech, gen. nov., Llanorella Alstrup & Olech, gen. nov., Phaeosporodendron Alstrup & Olech, gen. nov., and Prostratomyces Alstrup & Olech, gen. nov. Additionally, 31 species are described as new to science. These are: Antarctosphaeria bireagens Alstrup & Olech, sp. nov., A. lichenicola Alstrup & Olech, sp. nov., Arthonia dufayelensis Alstrup & Olech, sp. nov., A. livingstonensis Alstrup & Olech, sp. nov., A. massalongiae Alstrup & Olech, sp. nov., A. pertusariicola Alstrup & Olech, sp. nov., A. rakusae Alstrup & Olech, sp. nov., Carbonea austroshetlandica Alstrup & Olech, sp. nov., Cercidospora pertusariicola Alstrup & Olech, sp. nov., Dactylospora antarctica Alstrup & Olech, sp. nov., D. haematommatis Alstrup & Olech, sp. nov., Dahawkswia lichenicola Alstrup & Olech, sp. nov., Dendrophoma acarosporae Alstrup & Olech, sp. nov., Didymellopsis antarctica Alstrup & Olech, sp. nov., Lichenohostes citrinospora Alstrup & Olech, sp. nov., Lichenostigma corymbosae Alstrup & Olech, sp. nov., Llanorella ramalinae Alstrup & Olech, sp. nov., Metasphaeria verrucosa Alstrup & Olech, sp. nov., Micarea lichenicola Alstrup & Olech, sp. nov., Phaeospora antarctica Alstrup & Olech, sp. nov., P. convolutae Alstrup & Olech, sp. nov., Phaeosporodendron badiae Alstrup & Olech, sp. nov., Phoma acarosporae Alstrup & Olech, sp. nov., Prostratomyces leprariae Alstrup & Olech, sp. nov., P. ochrolechiae Alstrup & Olech, sp. nov., P. rhizocarpicolae Alstrup & Olech, sp. nov., Rhagadostoma antarctica Alstrup & Olech, sp. nov., Sphaerellothecium placopsiicola Alstrup & Olech, sp. nov., Stigmidium placopsiicola Alstrup & Olech, sp. nov., Taeniolella frigidae Alstrup & Olech, sp. nov., and Tetramelas caloplacae Alstrup & Olech, sp. nov. Furthermore, a literature survey was undertaken, which resulted in the preparation of an identification guide for the lichenicolous species occurring in the South Shetlands Islands.
... Low temperature, strong wind, short vegetation season and limited ice-free areas make Antarctica inhospitable for most terrestrial organisms. Therefore, biodiversity of ice-free regions is very low, with flora represented by only two native higher plants, and fauna limited mostly to micro-invertebrates and two species of macro-arthropods, Belgica antarctica Jacobs, 1900 and Parachlus steinenii Gercke, 1889 (Smith, 1984;Frenot et al., 2005;Hughes & Pertierra, ...
Article
Full-text available
Antarctica, with its severe conditions, is poor in terrestrial fauna species. However, an increase in human presence together with climate change may cause an influx of non-native species. Here we report a significant increase in colonized area of one of the few known invasive species to date in Antarctica. Non-native flies of Trichocera maculipennis have been recently observed in the Admiralty Bay area on King George Island, South Shetlands Islands, West Antarctica, 10 years after its first record in Maritime Antarctica (Maxwell Bay, King George Island). Its rapid spread across the island, despite geographic barriers such as glaciers, indicates successful adaptation to local environmental conditions and suggests this species is invasive. The mode of life of T. maculipennis , observed in natural and anthropogenous habitat and in laboratory conditions, is reported. The following adaptations enabled its invasion and existence within the sewage system in Antarctic scientific stations: the ability to survive in complete darkness, male ability to mate on the substrate surface without prior swarming in flight, and adaptation of terrestrial larvae to survive in semi-liquid food. Possible routes of introduction to Antarctica and between two bays on King George Island are discussed, as well as further research leading to the containment and eradication of this species.
... However, morphological plasticity is not accompanied by equally extensive genetic variability, which is generally low in the entire species range. A discrete decrease in genetic diversity is observed from the north to the south, with minimum values in the area of the Antarctic Peninsula(Holderegger et al., 2003;Chwedorzewska & Bednarek, 2008; van de Wouw et al., 2008).According to the literature, D. antarctica colonized Antarctica during the Holocene(Chapman, 1996;Lewis-Smith, 1984). In the paleobotanical research conducted byBirkenmajer et al. (1985), the fragments and pollen of D. antarctica isolated from peat cores were dated back at least five millennia. ...
... Las bajas temperaturas, los vientos fuertes, la corta temporada de vegetación y las áreas limitadas sin hielo hacen que la Antártida sea inhóspita para la mayoría de los organismos terrestres. La biodiversidad de flora está limitada a algas, líquenes y musgos y la fauna principalmente a microinvertebrados y dos especies de macroartrópodos, Belgica antarctica Jacobs, 1900 y Parachlus steinenii Gercke, 1889 (Smith, 1984;Frenot et al., 2005;Hughes & Pertierra, 2016). La aparición Boletín de la Sociedad Zoológica del Uruguay, 2020 Vol. ...
Article
Full-text available
Las invasiones biológicas se encuentran entre lasamenazas más importantes para la biodiversidad a nivelmundial. En general la introducción de nuevas especiesen regiones geográficas fuera de su lugar de origen seha producido por razones económicas, científicas ysociales teniendo un impacto, muchas veces conconsecuencias imprevistas. La Antártida es uno de loslugares más remotos de la Tierra y uno de los hábitatsmás prístinos. El aislamiento del continente Antárticollevaría a pensar que cuenta con pocas especiesinvasoras, sin embargo, desde la llegada de los humanosa las islas subantárticas, se ha registrado un aumento deespecies no autóctonas. La mayoría de las especiesintroducidas en el territorio Antártico no han podidosobrevivir a las condiciones climáticas, pero hay otrasque si lo han hecho como es el caso del díptero Trichocera(Saltrichocera) maculipennis Meigen, 1818. Dicha especiese registro por primera vez en 2006 en la Base CientíficaAntártica Artigas y continúa siendo reportada en variasBases científicas antárticas. Este trabajo presenta datossobre la abundancia de T. maculipennis en sitios de laBase Científica Antártica Artigas de la Isla Rey Jorgemediante el empleo y la efectividad de trampasalternativas utilizadas en el muestreo de esta especie.Se discuten los datos obtenidos a la luz de planes demitigación hacia programa de control y erradicación másefectivos de esta especie en instalaciones de las BasesCientíficas de la Isla Rey Jorge y evaluar la efectividadde trampas de pegamento utilizadas para el muestreo dela especie.
... Rights reserved. region, the climate is cold moist maritime (Lewis Smith 1984). Some of the lakes are influenced by the presence of seabirds, particularly penguins. ...
Article
Full-text available
Previous studies conducted in summer in the lakes at Hope Bay (Antarctic Peninsula) between 1991 and 2007 showed a large numerical contribution of flagellated Chrysophyceae to the phytoplankton communities, particularly in the oligotrophic lakes, as evidenced by light microscopy observations and molecular fingerprinting. Given the ecological relevance of this group in these Antarctic microbial foodwebs, we carried out further molecular analyses (clone libraries and 18S Illumina high throughput sequencing) to characterize their phylogenetic diversity. The results of this study significantly increased the retrieved Chrysophyceae biodiversity. Clone libraries in two selected lakes (one oligotrophic and one mesotrophic) yielded 12 different chrysophycean OTUs, whereas 81 Swarm OTUs were recovered from six lakes using Illumina HiSeq. With the combination of both methods, we observed sequences of all the chrysophyte known clades, although most of the diversity belonged to Clade D, a group comprising mixotrophic and heterotrophic species. The percentage of reads for this clade in Illumina HiSeq ranged from 30% to 96% of the total Chrysophyceae reads. Based on experiments and observations, we also describe the main ecological traits of this group: the dominant taxa were small pigmented flagellates, well adapted to survive in oligotrophic systems, sometimes abundant under ice-cover subjected to low light intensities, and that have phagotrophic behavior. The used combination of methods allowed us to characterize the biodiversity and ecology of the Chrysophyceae, the dominant phytoplankton group in the oligotrophic lakes of this Maritime Antarctic region.
... Показано, что у D. antarctica при температурных стрессах происходит также активация генов, кодирующих белок теплового шока (массой 70 кДа), который, возможно, обеспечивает низкотемпературный оптимум фотосинтеза (+13 о С) [11,65]. ...
Article
Full-text available
We critically survey peculiar aspects of the distribution patterns, ecology, ontogenesis and reproduction, anatomical, morphological, cytogenetic, and molecular genetics traits which are presumed to ensure the exclusive adaptation of Deschampsia antarctica to the conditions of the Maritime Antarctic. We analyze the specific traits of the plant and their potential significance in the exclusive dispersal of D. antarctica in the region. We state that such specific adaptations are absent and propose that D. antarctica (just like other Maritime Antarctic vascular plant species, Colobanthus quitensis) has been developing a set of adaptive strategies supposedly since the initial colonization back in a climatically more favorable time. These adaptive strategies, albeit presumably governed by mechanisms universal to vascular plants, have still some peculiar features which ensure the advantage of D. antarctica over other species attempting to colonize the region.
... Antarctic vegetation is dominated by bryophytes, with 116 species currently recognised representing cosmopolitan, endemic and bipolar taxa (Ochyra et al. 2008;Câmara et al. 2019). Mosses may form extensive carpets in some parts of Antarctica, particularly in the maritime Antarctic, contributing to the greatest development of 'fellfield' communities globally and providing habitats and ameliorating Antarctica's extreme environmental conditions for contained microbial and invertebrate communities (Smith 1984;de Carvalho et al. 2019;Prather et al. 2019). Well established Antarctic moss carpets may act as "sentinels" sensitive to environmental changes, particularly in temperature and hydration, across the Antarctic Peninsula region (Prather et al. 2019). ...
Article
Full-text available
We evaluated fungal and bacterial diversity in an established moss carpet on King George Island, Antarctica, affected by ‘fairy ring’ disease using metabarcoding. A total of 127 fungal and 706 bacterial taxa were assigned. Ascomycota dominated the fungal assemblages, followed by Basidiomycota, Rozellomycota, Chytridiomycota, Mortierellomycota and Monoblepharomycota. The fungal community displayed high indices of diversity, richness and dominance, which increased from healthy through infected to dead moss samples. A range of fungal taxa were more abundant in dead rather than healthy or fairy ring moss samples. Bacterial diversity and richness were greatest in healthy moss and least within the infected fairy ring. The dominant prokaryotic phyla were Actinobacteriota, Proteobacteria, Bacteroidota and Cyanobacteria. Cyanophyceae sp., whilst consistently dominant, were less abundant in fairy ring samples. Our data confirmed the presence and abundance of a range of plant pathogenic fungi, supporting the hypothesis that the disease is linked with multiple fungal taxa. Further studies are required to characterise the interactions between plant pathogenic fungi and their host Antarctic mosses. Monitoring the dynamics of mutualist, phytopathogenic and decomposer microorganisms associated with moss carpets may provide bioindicators of moss health.
... An inverse correlation between Antarctic bacterial diversity and density and latitude has been noted for soils without vegetative cover [20,21]. It is also documented for the native fauna and flora [22,23]. However, several studies, including ones conducted in other continents, have found no such trend [24,25] or have attributed the trend to other factors, such as soil pH [26]. ...
Article
Full-text available
Antarctica represents a unique environment, both due to the extreme meteorological and geological conditions that govern it and the relative isolation from human influences that have kept its environment largely undisturbed. However, recent trends in climate change dictate an unavoidable change in the global biodiversity as a whole, and pristine environments, such as Antarctica, allow us to study and monitor more closely the effects of the human impact. Additionally, due to its inaccessibility, Antarctica contains a plethora of yet uncultured and unidentified microorganisms with great potential for useful biological activities and production of metabolites, such as novel antibiotics , proteins, pigments, etc. In recent years, amplicon-based next-generation sequencing (NGS) has allowed for a fast and thorough examination of microbial communities to accelerate the efforts of unknown species identification. For these reasons, in this review, we present an overview of the archaea, bacteria, and fungi present on the Antarctic continent and the surrounding area (maritime Antarctica, sub-Antarctica, Southern Sea, etc.) that have recently been identified using amplicon-based NGS methods.
... Zudem können die Konzentrationen von Phosphor, Stickstoff und Kalium unter Pflanzendecken höher liegen als auf vegetationsfreiem Untergrund (Roberts et al., 2009). Ein zusätzlicher Nährstoffeintrag durch Seevögel und Robben kann sich ebenfalls positiv auswirken, da Böden in der Antarktis im Allgemeinen als nährstoffarm gelten (Lewis- Smith, 1984). Eine Ausnahme bildet die unmittelbare Umgebung von Brutplätzen von Seevögeln (Simas et al., 2007;Abakumov & Alekseev, 2018;Łachacz et al., 2018). ...
Technical Report
Full-text available
Antarctica and the surrounding Southern Ocean are under increasing pressure from cumulative impacts of climate change, pollution, fisheries, tourism and a variety of other human activities. These changes pose a high risk both to local polar ecosystems and to the regulation of the global climate, as well as through global sea-level rise. Thus, long-term monitoring programmes serve to assess the state of ecosystems as well as to make projections for future developments. The Fildes Region in the southwest King George Islands (South Shetland Islands, Maritime Antarctica), consisting of the Fildes Peninsula, Ardley Island and several offshore islands, is one of the largest ice-free areas in the Maritime Antarctic. As a continuation of a long-term monitoring programme started in the 1980s, local breeding bird and seal populations were recorded during the summer months (December, January, February) of the 2018/19 and 2019/20 seasons and supplemented by individual count data for the 2020/21 season. This study presents the results obtained, including the population development of the local breeding birds. Here, some species showed stable populations in a long-term comparison (brown skuas, southern polar skuas) or a significant increase (gentoo penguin, southern giant petrel). Other species, however, recorded significant declines in breeding pair numbers (Adélie penguin, chinstrap cenguin, Antarctic tern, kelp gull) up to an almost complete disappearance from the breeding area (cape petrel). In addition, the number of seals at their haul-out sites was recorded and the distribution of all seal reproduction sites in the Fildes Region was presented. Furthermore, data on the breeding bird population in selected areas of Maxwell Bay were added. Additionally, the rapid expansion of the Antarctic hairgrass was documented with the help of a completed repeat mapping. The documentation of glacier retreat areas of selected areas of Maxwell Bay was updated using satellite imagery and considered in relation to regional climatic development. Furthermore, the distribution and amount of marine debris washed up in the Fildes Region and the impact of anthropogenic material on seabirds will are addressed. In addition, the current knowledge of all introduced non-native species in the study area and the need for further research are presented.
... The environmental conditions in Antarctica, such as low temperatures, high wind speeds, excessive UV-B radiation, and aridity are limiting for plant growth and survival (Longton 1979), with strong influence on soil properties and distribution (Bockheim 2015). Restricted to icefree areas of maritime Antarctica, the vegetation cover is mainly cryptogamic communities dominated by lichens, mosses, fungi, algae, and cyanobacteria, mainly forming cryptogamic associations (Smith 1984). ...
Article
Full-text available
Abstract Antarctic plant communities show a close relationship with soil types across the landscape, where vegetation cover changes, biological influence, and soil characteristics can affect the dynamic of greenhouse gases emissions. Thus, the objective of this study was to evaluate greenhouse gases emissions in lab conditions of ice-free areas along a topographic gradient (from sea level up to 300 meters). We selected 11 distinct vegetation compositions areas and assessed greenhouse gases production potentials through 20 days of laboratory incubations varying temperatures at -2, 4, 6, and 22 °C. High N2O production potential was associated with the Phanerogamic Community under the strong ornithogenic influence (phosphorus, nitrogen, and organic matter contents). Seven different areas acted as N2O sink at a temperature of -2 °C, demonstrating the impact of low-temperature conditions contributing to store N in soils. Moss Carpets had the highest CH4 emissions and low CO2 production potential. Fruticose Lichens had a CH4 sink effect and the highest values of CO2. The low rate of organic matter provided the CO2 sink effect on the bare soil (up to 6 °C). There is an overall trend of increasing greenhouse gases production potential with increasing temperature along a toposequence.
... It is a cold desert with an annual precipitation maximum of up to 200 mm in the coastal habitats and much lesser in continental Antarctica. Two biogeographic zones can be recognized within the continent-the continental and maritime Antarctica (Smith 1984;Convey 2001), which are further categorized into sixteen eco-regions (Terauds and Lee 2016) (Fig. 1). Antarctica vegetation is primarily dominated by cryptogams, i.e. bryophytes and lichens, except for two vascular plants Deschampsia antarctica Desv. ...
Chapter
Full-text available
Antarctica is one of the very few ecosystems in the world with minimum anthropogenic interventions and pollution load. The extreme climatic conditions such as temperature, precipitation, and smaller ice-free regions allow only cryptogams such as bryophytes and lichens to grow dominantly. Although lichens are well-known biomonitors and bioindicators of climate change, environmental pollution and anthropogenic perturbations, their potential has been explored very recently. In this chapter, various climate-change studies in Antarctica employing lichens as an integrated bioindicator system are reviewed. The studies utilized either natural gradients of climate across the continent or passive or active air temperature enhancement experiments. The lichen communities in Antarctica has been found sensitive to both climatic clines and temperature manipulations. The lichens’ response was species-specific, the species with wider distribution were more adaptive to climate change than those with restricted distribution. The studies also indicated that climate warming would cause the extinction of sensitive species. Simultaneously, some will increase their geographical extension due to the increased water availability and nutrients in changed ecosystems.
... Bununla birlikte bu bitkinin dağılım coğrafyası ise Andes bölgesinin bir kısmını ve Falkland adalarını içine alan Sub-Antarktika'yı kapsamaktadır. Bu bitki, kendi kendine döllenen ve kendine tozlanan bir bitkidir [41,42,44,45]. Antarktika'nın koşullarına karşın bu bitki hemen hemen her yıl bolca çiçek açmakta, tozlaşma ve döllenmeden sonra tohum üretmektedir. ...
Article
Full-text available
Yeryüzünde insanlar tarafından en son keşfedilen, en yüksek, en soğuk, en kurak ve nüfus yoğunluğu en az olan kıta Antarktika’dır. Aynı zamanda yeryüzünün kullanılabilen tatlı su kaynaklarının yaklaşık % 70’i buz halinde bu kıtada bulunmaktadır. Bu özellikleriyle geçmişten günümüze insan yaşamı olmadığı halde canlı yaşama doğal seleksiyon ile devam etmiştir. Antarktika, üzerinde barındırdığı doğal yaşam habitatlarıyla, bilim insanları için sınırları tüm kıta olan eşsiz bir laboratuvar gibidir. Antarktika’da az sayıda olmakla birlikte kıtaya özgü olan hayvan ve bitki türleri ile çeşitli alg, liken ve mikroorganizma türleri bulunmaktadır. Bilim insanları bu canlı formları üzerinde araştırmalar yaparak, küresel ısınma ve çevre problemleri gibi güncel sorunlara bir çözüm aramaktadırlar. Kıtadan izole edilen bazı türler, enzimler ve genler kullanılarak başta biyolojik kontrol olmak üzere biyoteknoloji, biyoremidasyon gibi farklı alanlarda çalışmalar devam etmektedir. Bu çalışmada, Antarktikada gerçekleştirilen yaşam bilimleri ve biyoteknoloji araştırmaları gözden geçirilmiştir.
... Of the relatively pristine sub-Antarctic islands, Heard Island, which lies to the south of the Antarctic Polar Front and on the eastern edge of the South Indian Province of the Southern Ocean (Lewis Smith, 1984;Green and Woehler, 2006), is the least disturbed by biological invasions. Although some non-indigenous species were introduced to Heard Island in the past (e.g., van den Hoff et al., 2012), most failed to establish. ...
Article
The Antarctic climate-diversity-invasion hypothesis (ACDI) predicts that in Antarctic soil systems, climate change should lead to increases in the abundance and diversity of indigenous assemblages. Where biological invasions have occurred, however, invasive alien species should have negative effects on indigenous faunal assemblages. To assess these predictions, we provide the first systematic ecological survey of the Collembola assemblages of pristine, sub-Antarctic Heard Island (53.1°S, 73.5°E) and compare the results to similarly conducted surveys of three other sub-Antarctic islands (Marion, Prince Edward, and Macquarie), characterised by assemblages including invasive Collembola. In particular, we examine differences in densities of three indigenous species (Cryptopygus antarcticus, Mucrosomia caeca, Tullbergia bisetosa) shared between the invaded islands and Heard Island. On average, density of these species was four or more-fold significantly lower on the invaded islands than on uninvaded Heard Island. Yet mean assemblage densities of springtails, accounting for variation among vegetation communities, did not differ substantially or significantly among the islands, suggesting that compensatory dynamics may be a feature of these systems. The invasion impact prediction of the ACDI is therefore supported. On Heard Island, indigenous assemblage variation is strongly related to vegetation community and less so to elevation, in keeping with investigations of Collembola assemblage variation elsewhere across the Antarctic. These findings, in the context of field experimental and physiological data on Collembola from the region, suggest that the climate-diversity predictions of the ACDI will play out in different ways across the Antarctic, depending on whether precipitation increases or decreases as climates change.
Chapter
Full-text available
This chapter deliberates Dronning Maud Land's glacial history (DML) based on available dates obtained using cosmogenic radionuclides. As Dronning Maud Land is a part of the East Antarctica Ice Sheet (EAIS), background information about EAIS and its glacial history is also discussed based on the researchers' various evidence. A comprehensive outline of DML, the basics of cosmogenic radionuclide and its application and major glacial events from DML are presented in this chapter. Further, meltwater's pulse due to deglaciation of EAIS and evidence related to the marine isotope stages were discussed to understand the impact of deglaciation on the global ocean. A very few direct dates were available from Dronning Maud Land to establish the detailed glacial chronology, or some of the results are contradicting. This region shows sparse or no evidence of ice thickening during the last glacial maximum (LGM). Field observations and ice core models show that the ice sheet's interior parts, the ice dome, were possibly 100 m lower during LGM than the present. The results obtained by the various researchers shows that around 600 m high ice sheet existed 4 million years ago, which is decreasing continuously to the present day.
Article
Full-text available
Background Ice-free areas in the Antarctic region are strongly limited. The presence of marine mammals and birds in those areas influence soil properties and vegetation composition. Studies on the terrestrial diatom flora in soils influenced by sea birds in the Maritime Antarctic region are scarce. Methods Samples were collected from two transects on the western shore of the Admiralty Bay region. Light and scanning electron microscopic observations and statistical analyses were conducted to consider the impact of penguin rookeries on soil diatom assemblages. Results The disturbance associated with the presence of penguin rookeries clearly influences the soil diatom diversity. Assemblages from areas with the highest nutrient input were characterized by a much lower diversity with only few species dominating the flora. One of recorded taxa could not be assigned to any of the known species. Therefore, based on the combination of morphological features analyzed using light and scanning electron microscopes and comparison with similar taxa in the Antarctic region and worldwide, the species is described hereby as new to science– Luticola kaweckae sp.nov. The new species is characteristic for soil habitats with strong penguin influence.
Article
Microfungi were isolated from 54 lichen, moss and plant samples collected at two sites (Polish research station ‘Arctowski’ and Argentinean station ‘Jubany’) on King George Island, Antarctica. Fifty-eight taxa, mainly fungi imperfecti, and 63 different types of sterile mycelia were isolated. Seventeen of the identified taxa and 15 sterile types were relatively abundant and were recorded from three samples or more. The distribution of these taxa in the different sample types was analyzed by correspondence analysis. Geographic sampling site tended to be a more relevant indicator of taxonomic composition of mossand lichen-derived fungal assemblages than the exact nature of the sample. In contrast, some plant-derived species were similar in all plants irrespective of sampling site. In general, the distribution of fungi in samples from ‘Jubany’ was more distinctive than in ‘Arctowski’ samples, possibly due to the stronger influence of humans and animals in the vicinity of the latter station. With respect to temperature requirements for radial growth, 44% of all isolates were mesophilic, 46% psychrotolerant and 10% psychrophilic. The ratios among these groups in plants, mosses and lichens were not identical. Taxa isolated from plants were more often psychrotolerant than mesophilic or psychrophilic. In contrast, a trend indicating a higher proportion of psychrophiles from lichens and a higher proportion of mesophiles from mosses was observed.
Chapter
Full-text available
Bryophytes are considered pioneer organisms in the colonization of habitats due to their capacity of adaptation. Therefore, many of the species are cosmopolitan, being found from the deserts of Australia to the tropical forests like the Amazon, being present from the bogs of the Northern Hemisphere to inhospitable environments such as Antarctica. The Antarctic continent is the fifth largest continent in extension, with about 13.7 squared million km. The Antarctic ecosystem can be divided into latitudinal zones that correspond to a distinct climatic region, being subdivided into Maritime Antarctica, Antarctic Peninsula and Continental Antarctica. It is a continent of climatic extremes in which strong winds, low rainfall and high UV-A and UV-B radiation are recorded. Plant communities in Antarctica are described according to the presence of the dominant species, basically bryophytes. The bryoflora in Antarctica consists of about 111 species, which belong to 55 genera and 17 families, subdivided into six distinct phytogeographic elements that comprise several species for each element. From this division, it can be observed that most of the moss found in Antarctica has a bipolar distribution. Mosses are considered pioneer species in the process of vegetational succession of this habitat, due to their abundance, leading to the establishment of plant communities along with lichens and fungi. The species of bryophytes present in Antarctica remain subdivided into two taxonomic groups: Marchantiophyta (hepatic) and Bryophyta (mosses). Due to the adaptive capacity in extreme environments, the mosses present developed strategies that confer them survival in the Antarctic and thus providing a geographic distribution directly related to abiotic factors, besides presenting an ecological interaction with the other vegetal species, fungi and fauna of the region.
Article
Full-text available
The present study compiles the results of inventory of cyanobacteria species from the polar desert zone of Europe. The checklist includes actualized literature data from Franz Josef Land and Novaya Zemlya archipelagos , most of which are published in Russian, and the data from Svalbard archipelago. After the revision of nomenclature, the current checklist contains 176 species of cyanobacteria. The data on site characteristics, habitats , species frequency are provided. The study is the first generalization of the biodiversity of cyanobacteria in the European polar deserts, and it is important for the knowledge about their distribution and biodiversity in the Arctic. The flora analysis showed a decreasing trend of cyanobacterial biodiversity towards high latitude areas.
Article
Full-text available
ABSTRACT Snow Island is part of the South Shetland Archipelago in Antarctica. Most of its surface is permanently covered by snow, yet it has an important paleobotanical site. There are no protected areas on the island and no recent data regarding its vegetation. This study aimed to collect and identify fresh samples of bryophytes from President Head Peninsula of Snow Island. Samples were collected during the summers of 2015 and 2018. Among the 24 bryophyte species identified in this work, 19 are new occurrences for Snow Island, bringing the total known for the island to 29 species. The most diverse family is Pottiaceae, with four species of two genera, followed by Bryaceae and Polytrichaceae, with three species each. The results show that the diversity of mosses on Snow Island is greater than previously reported. We here demonstrated the region's importance and the 190 % increase in Snow Island species number. This study also updated the Antarctic distribution of some species.
Article
Full-text available
The invertebrate terrestrial fauna of Antarctica is being investigated with increasing interest to discover how life interacts with the extreme polar environment and how millions of years of evolution have shaped their biodiversity. Classical taxonomic approaches, complemented by molecular tools, are improving our understanding of the systematic relationships of some species, changing the nomenclature of taxa and challenging the taxonomic status of others. The springtail Friesea grisea has previously been described as the only species with a “pan-Antarctic” distribution. However, recent genetic comparisons have pointed to another scenario. The latest morphological study has confined F. grisea to the sub-Antarctic island of South Georgia, from which it was originally described, and resurrected F. antarctica as a congeneric species occurring on the continental mainland. Molecular data demonstrate that populations of this taxon, ostensibly occurring across Maritime and Continental Antarctica, as well as on some offshore islands, are evolutionarily isolated and divergent and cannot be included within a single species. The present study, combining morphological with molecular data, attempts to validate this hypothesis and challenges the taxonomic status of F. antarctica, suggesting that two additional new species, described here as Friesea gretae sp. nov. and Friesea propria sp. nov., are present in Continental Antarctica.
Article
Full-text available
We present a data set on Antarctic biodiversity for the phylum Rotifera, making it publicly available through the Antarctic Biodiversity Information facility. We provide taxonomic information, geographic distribution, location, and habitat for each record. The data set gathers all the published literature about rotifers found and identified across the Continental, Maritime, and Subantarctic biogeographic regions of Antarctica. A total of 1455 records of rotifers in Antarctica found from 1907 to 2018 is reported, with information on taxonomic hierarchies, updated nomenclature, geographic information, geographic coordinates, and type of habitat. The aim is to provide a georeferenced data set on Antarctic rotifers as a baseline for further studies, to improve our knowledge on what has been considered one of the most diverse and successful groups of animals living in Antarctica.
Chapter
Climate driven changes in the Southern Ocean impact biological communities and processes. Monitoring these changes requires systematic and periodic data collection on indicator taxa such as seabirds, which act as ecosystem sentinels. Understanding their breeding behaviour and phenology helps assess the impacts of anthropogenic pressure and environmental variations on seabird populations. Antarctic Wildlife Monitoring Program of Wildlife Institute of India is currently evaluating the population status, distribution and genetic structure of key seabird species (Adelie penguin, snow petrel, south polar skua, Wilson’s storm petrel) breeding around Indian research stations. This chapter discusses the results of work being conducted on snow petrel, a climate-dependent seabird found in the ice-free coastal areas and inland mountains in Antarctica. Monitoring snow petrel populations in east Antarctica is critical to understanding their populations’ response to climate change and predicting future impacts.
Chapter
Antarctica is known for the adverse climatic conditions and high UV-B radiations; thus, it reveals only climatically adapted flora and fauna. Cryptogams are the main flora of Antarctica and are dominated by lichens, followed by mosses and algae. Antarctic floral diversity reveals that pigments’ synthesis plays an essential role in their survival, growth, development, and diversity during the annual spring. Antarctic cryptogams are growing in the photosynthetically active radiation (PAR) and ultraviolet radiations (UV-R), closely associated with photosynthetic and photoprotective synthesise pigments. Antarctic cryptogams cope with high UV radiation stress by synthesising UV-absorbing compounds; UV-B absorbs pigments and other compounds; the pigment synthesis protects cryptogamic flora. In lichens, usnic acid, perlatolic acid, and fumar photometric acid, mainly induced by, UV-B radiation, provide protection. In other lichens, secondary metabolites such as phenolics, atranorin, parietin and melanin also enhance the plant defence against UV radiation. In mosses, neoxanthin, violaxanthin, lutein, epoxide, anteraxanthin, zeaxanthin, UV absorbing, and phenolics are the important pigments synthesised by the plants under stress conditions. In Antarctic aquatic algae, algal pigments such as mycosporine-like amino acids, violaxanthin and β-carotene are present for protection. In a comparative study of pigments of plants growing in different regions of Antarctica, it was observed that these plants have a well-developed mechanism of synthesis of a wide variety of pigments in higher concentrations to cope with the UV radiation and other adverse environmental conditions.
Chapter
The polar tundra occurs almost exclusively in the Arctic region. In Antarctica, there are only two flowering plant species, as opposed to just over 2,000 in the Arctic, and in addition about 1,800 cryptogam species. The geographical distribution of the flora of the Arctic is closely connected to the vegetation history in the Pleistocene, and it shows phylogenetic relationships to the flora of the nemoral and boreal high mountains. The plant life forms are similar to those of the alpine flora, and small-scale mosaics on cryo-disturbed soils are characteristic.
Preprint
Full-text available
We evaluated fungal and bacterial diversity in an established moss carpet on King George Island, Antarctica, affected by ‘fairy ring’ disease using metabarcoding. These microbial communities were assessed through the main stages of the disease. A total of 127 fungal and 706 bacterial taxa were assigned. The phylum Ascomycota dominated the fungal assemblages, followed by Basidiomycota , Rozellomycota , Chytridiomycota , Mortierellomycota and Monoblepharomycota . The fungal community displayed high indices of diversity, richness and dominance, which increased from healthy through infected to dead moss samples. Bacterial diversity and richness were greatest in healthy moss and least within the infected fairy ring. Chalara sp. 1, Alpinaria sp., Helotiaceae sp. 2, Chaetothyriales sp. 1, Ascomycota sp. 1, Rozellomycota sp. and Fungi sp. were most abundant within the fairy ring samples. A range of fungal taxa were more abundant in dead rather than healthy or fairy ring moss samples. The dominant prokaryotic phyla were Actinobacteriota , Proteobacteria , Bacteroidota and Cyanobacteria . The taxon Cyanobacteriia sp., whilst consistently dominant, were less abundant in fairy ring samples. Microbacteriaceae sp. and Chloroflexi sp. were the most abundant taxa within the fairy rings. Our data confirmed the presence and abundance of a range of plant pathogenic fungi, supporting the hypothesis that the disease is linked with multiple fungal taxas. Further studies are required to characterise the interactions between plant pathogenic fungi and their host Antarctic mosses. Monitoring the dynamics of mutualist, phytopathogenic and decomposer microorganisms associated with moss carpets may provide bioindicators of moss health.
Article
Antarctica and the Southern Ocean are unique natural laboratories where organisms adapted to extreme environmental conditions have evolved in isolation for millions of years. These unique biotic communities on Earth are facing complex climatic and environmental changes. Terrestrial ecosystems in the Antarctic Peninsula Region (APR) have experienced the highest rate of climate warming and, being the most impacted by human activities, are facing the greatest risk of detrimental changes. This review provides an overview of the most recent findings on how biotic communities in terrestrial ecosystems of the Antarctic Peninsula Region (APR) are responding and will likely respond to further environmental changes and direct anthropogenic impacts. Knowledge gained from studies on relatively simple terrestrial ecosystems could be very useful in predicting what may happen in much more complex ecosystems in regions with less extreme temperature changes. The rapid warming of the APR has led to the retreat of glaciers, the loss of snow and permafrost and the increase of ice-free areas, with a consequent enhancement of soil-forming processes, biotic communities, and food web complexity. However, most human activity is concentrated in APR coastal ice-free areas and poses many threats to terrestrial ecosystems such as environmental pollution or disturbances to soilcommunities and wildlife. People who work or visit APR may inadvertently introduce alien organisms and/or spread native species to spatially isolated ice-free areas. The number of introduced non-indigenous species and xenobiotic compounds in the APR is likely to be greater than currently documented, and several biosecurity and monitoring activities are therefore suggested to Antarctic national scientific programs and tourism operators to minimize the risk of irreversible loss of integrity by the unique terrestrial ecosystems of APR.
Chapter
Terrestrial environments of Antarctica include some of the most extreme on Earth, challenging the very existence of life itself. This article outlines briefly the geological and biological history of the continent, leading on to the conditions currently experienced, before describing its terrestrial biogeography and biota. Major determinants of terrestrial biodiversity and ecosystem function are discussed and consideration given to natural and human-induced processes of ecosystem development and change.
ResearchGate has not been able to resolve any references for this publication.