Moss Banks Research Articles

Do spectral reflectance indices distinguish between the greenness in three different moss species in moss banks on Galindez Island (Argentine Islands)?

Spectral reflectance indices of green state of Warnstorfia fontinaliopsis, Chorisodontium aciphyllum and Sanionia georgicouncinata on moss bank in the Galindez Island (Argentine Islands) were measured using a handheld spectrometer PolyPen RP 410 UVIS (Photon Systems Instruments, Drásov, Czech Republic) within the range of 380–790 nm in order to find suitable ones for effective classification of moss species within the same colour state (green). Among altogether 19 indices tested, there were some which did not differ significantly between the studied species (subgroup 1). Other indices (subgroup 2) were sensitive enough to distinguish one of the studied species from the others, and finally (subgroup 3), they were found statistically significantly different for all studied moss species. Also, the indices calculated at wavelengths typical for UAV spectral cameras (green, red and red edge channels) showed species-specific differences and can be potentially used to distinguish between different mosses within the same green physiological state indicating a good vigor.

From acidophilic to ornithogenic: microbial community dynamics in moss banks altered by gentoo penguins.

The study explores the indirect impact of climate change driven by gentoo's penguin colonization pressure on the microbial communities of moss banks formed by Tall moss turf subformation in central maritime Antarctica. Microbial communities and chemical composition of the differently affected moss banks (Unaffected, Impacted and Desolated) located on Galindez Island and Сape Tuxen on the mainland of Kyiv Peninsula were analyzed. The native microbiota of the moss banks' peat was analyzed for the first time, revealing a predominant presence of Acidobacteria (32.2 ± 14.4%), followed by Actinobacteria (15.1 ± 4.0%) and Alphaproteobacteria (9.7 ± 4.1%). Penguin colonization and subsequent desolation of moss banks resulted in an increase in peat pH (from 4.7 ± 0.05 to 7.2 ± 0.6) and elevated concentrations of soluble nitrogen (from 1.8 ± 0.4 to 46.9 ± 2.1 DIN, mg/kg) and soluble phosphorus compounds (from 3.6 ± 2.6 to 20.0 ± 1.8 DIP, mg/kg). The contrasting composition of peat and penguin feces led to the elimination of the initial peat microbiota, with an increase in Betaproteobacteria (from 1.3 ± 0.8% to 30.5 ± 23%) and Bacteroidota (from 5.5 ± 3.7% to 19.0 ± 3.7%) proportional to the intensity of penguins' impact, accompanied by a decrease in community diversity. Microbial taxa associated with birds' guts, such as Gottschalkia and Tissierella, emerged in Impacted and Desolated moss banks, along with bacteria likely benefiting from eutrophication. The changes in the functional capacity of the penguin-affected peat microbial communities were also detected. The nitrogen-cycling genes that regulate the conversion of urea into ammonia, nitrite oxide, and nitrate oxide (ureC, amoA, nirS, nosZ, nxrB) had elevated copy numbers in the affected peat. Desolated peat samples exhibit the highest nitrogen-cycle gene numbers, significantly differing from Unaffected peat (p < 0.05). The expansion of gentoo penguins induced by climate change led to the replacement of acidophilic microbiomes associated with moss banks, shaping a new microbial community influenced by penguin guano's chemical and microbial composition.

Impact of Environmental Factors on the Moss Banks’ State in Argentine Islands (West Antarctica): Interannual Monitoring

Impact of Environmental Factors on the Moss Banks’ State in Argentine Islands (West Antarctica): Interannual Monitoring

Moss bank composition on Galindez Island (Argentine Islands, maritime Antarctic)

Moss bank composition on Galindez Island (Argentine Islands, maritime Antarctic)

The contribution of Antarctic moss peat to the understanding of global peatland processes

AbstractThe moss banks of the Maritime Antarctic composed of one or both of the mosses Chorisodontium aciphyllum and Polytrichum strictum form peat banks up to 3.4 m thick and 5500 years of age. They represent perhaps the simplest peat-forming systems in the world, so studying their dynamics can help in the understanding of peatland dynamics generally, particularly those of temperate blanket peat. They can provide insights into how the balance of growth, decomposition and compaction of peat results in peat formation, how downhill creep can be the cause of both vertical edges and the creation of patterned bogs and how erosion of peat can be a natural process.

Minimizing tourist impact on the Argentine Islands ecosystem, Antarctic Peninsula, using visitor site guidelines approach

There has been an ongoing increase in tourist visits to the Antarctic since 2010. These visits primarily concentrate on a small number of sites, increasing the possible environmental impact. One of the tourism hotspots is the central Argentine Islands in Wilhelm Archipelago. These islands, being one of the top 20 most visited Antarctic sites, consist of Galindez Island, Winter Island, and Skua Island. They are known for wildlife, rich vegetation (old moss banks, rich bryophyte and lichen communities, Antarctic pearlwort Colobanthus quitensis and hairgrass Deschampsia antarctica populations), spectacular views. They include one of the oldest Antarctic research stations: the Ukrainian Antarctic Akademik Vernadsky station. Previously no measures have been developed to minimize the impact of tourism on this region. Thus, the Visitor Site Guidelines (VSG) approach and the numerous studies in the region were used to determine the central values of this site and to identify those key features that can be opened for tourists. In addition to the most frequently mentioned values, such as seabirds and mammals, we considered it necessary to mention the vegetation. We assessed threats to these values, distinguishing known and potential impacts. We have also analyzed and developed landing requirements for the studied area, including the most critical requirement to be considered, namely the number of visitors. We think that the maximum number of visitors should be 36 at any time and 270 per day, not counting passengers of yachts. This is the first time that the Visitor Site Guidelines were modified to limit the number of yachts visiting the site to three yachts per day. To reduce the tourist load at the station itself and at the same time to concentrate tourists in the studied region, we proposed two tourist trails: one for Galindez Island, the other — the existing trail for Winter Island. The prepared draft of Visitor Site Guidelines is given in Appendix 2.

Low genetic variation between South American and Antarctic populations of the bank-forming moss Chorisodontium aciphyllum (Dicranaceae)

The Antarctic–South American bank-forming moss Chorisodontium aciphyllum is known for having the oldest sub-fossils of any extant plant in Antarctica as well as extreme survival abilities, making it a candidate species for possible long-term survival in Antarctica. Applying phylogeographic and population genetic methods using the plastid markers trnL-F and rps4 and the nuclear internal transcribed spacer, we investigated the genetic diversity within C. aciphyllum throughout its range. Low genetic variation was found in all loci, both between and within Antarctic and southern South American populations, suggesting a relatively recent (likely within the last million years) colonization of this moss to the Antarctic, as well as a likely severe bottleneck during Pleistocene glaciations in southern South America. We also performed a simple atmospheric transfer modeling approach to study potential colonization rates of small (microscopic/microbial) or spore-dispersed organisms (such as many mosses and lichens). These suggested that the northern Antarctic Peninsula shows potentially regular connectivity from southern South America, with air masses transferring, particularly southbound, between the two regions. We found elevated genetic variation of C. aciphyllum in Elephant Island, also the location of the oldest known moss banks (> 5500 years), suggesting this location to be a genetic hotspot for this species in the Antarctic.

Peatland Ecosystem Processes in the Maritime Antarctic During Warm Climates

We discovered a 50-cm-thick peat deposit near Cape Rasmussen (65.2°S), in the maritime Antarctic. To our knowledge, while aerobic ‘moss banks’ have often been examined, waterlogged ‘peatlands’ have never been described in this region before. The waterlogged system is approximately 100 m2, with a shallow water table. Surface vegetation is dominated by Warnstorfia fontinaliopsis, a wet-adapted moss commonly found in the Antarctic Peninsula. Peat inception was dated at 2750 cal. BP and was followed by relatively rapid peat accumulation (~0.1 cm/year) until 2150 cal. BP. Our multi-proxy analysis then shows a 2000-year-long stratigraphic hiatus as well as the recent resurgence of peat accumulation, sometime after 1950 AD. The existence of a thriving peatland at 2700–2150 cal. BP implies regionally warm summer conditions extending beyond the mid-Holocene; this finding is corroborated by many regional records showing moss bank initiation and decreased sea ice extent during this time period. Recent peatland recovery at the study site (<50 years ago) might have been triggered by ongoing rapid warming, as the area is experiencing climatic conditions approaching those found on milder, peatland-rich sub-Antarctic islands (50–60°S). Assuming that colonization opportunities and stabilization mechanisms would allow peat to persist in Antarctica, our results suggest that longer and warmer growing seasons in the maritime Antarctic region may promote a more peatland-rich landscape in the future.

Ecology of moss banks on Signy Island (maritime Antarctic)

Mosses are dominant components of high-latitude environments, and Signy Island (maritime Antarctic) provides a representative example of polar cryptogam-dominated terrestrial ecosystems. In 2011, we mapped all moss banks, their characteristics (thickness, area, floristic composition) and investigated their relationship with selected environmental factors including topography (elevation, slope, aspect), biotic disturbance (fur seals), deglaciation age of the surfaces, location on the eastern vs. western side of the island and snow cover as a proxy of water supply during the summer (December). We here identify the most important environmental factors influencing moss bank characteristics and distribution and provide a baseline for future monitoring. Moss bank abundance and distribution are the result of the interaction of multiple abiotic and biotic factors acting at different spatial scales. The most important factors are the location of moss banks on the eastern vs. western side of the island at the macroscale (with thicker and larger moss banks and a prevalence of Chorisodontium aciphyllum on the western side) and their favourable aspect (mainly N, NW) at the microscale, providing better microclimatic conditions suitable for their development. The elevation threshold detected at 120 m could indicate the occurrence of a ‘moss bank line’, analogous to the tree line, and corresponds with a threshold of mean annual temperature of −4.8 °C. The other factors examined play a subsidiary role in affecting bank distribution and characteristics. These findings allow a better understanding of this key feature of maritime Antarctic vegetation and provide quantitative information about their ecology.

Greening the Antarctic.

Climate Change![Figure][1] Antarctic moss banks show increased biological activity consistent with the effects of warming temperatures. PHOTO: CARLOS FAIRBAIRN The ecological consequences of climate change in the polar regions are becoming increasingly evident. A study in the Antarctic now

Widespread Biological Response to Rapid Warming on the Antarctic Peninsula

Recent climate change on the Antarctic Peninsula is well documented [1-5], with warming, alongside increases in precipitation, wind strength, and melt season length [1, 6, 7], driving environmental change [8, 9]. However, meteorological records mostly began in the 1950s, and paleoenvironmental datasets that provide a longer-term context to recent climate change are limited in number and often from single sites [7] and/or discontinuous in time [10, 11]. Here we use moss bank cores from a 600-km transect from Green Island (65.3°S) to Elephant Island (61.1°S) as paleoclimate archives sensitive to regional temperature change, moderated by water availability and surface microclimate [12, 13]. Mosses grow slowly, but cold temperatures minimize decomposition, facilitating multi-proxy analysis of preserved peat [14]. Carbon isotope discrimination (Δ13C) in cellulose indicates the favorability of conditions for photosynthesis [15]. Testate amoebae are representative heterotrophs in peatlands [16-18], so their populations are an indicator of microbial productivity [14]. Moss growth and mass accumulation rates represent the balance between growth and decomposition [19]. Analyzing these proxies in five cores at three sites over 150 years reveals increased biological activity over the past ca. 50 years, in response to climate change. We identified significant changepoints in all sites and proxies, suggesting fundamental and widespread changes in the terrestrial biosphere. The regional sensitivity of moss growth to past temperature rises suggests that terrestrial ecosystems will alter rapidly under future warming, leading to major changes in the biology and landscape of this iconic region-an Antarctic greening to parallel well-established observations in the Arctic [20].

Invited review: climate change impacts in polar regions: lessons from Antarctic moss bank archives.

Mosses are the dominant plants in polar and boreal regions, areas which are experiencing rapid impacts of regional warming. Long-term monitoring programmes provide some records of the rate of recent climate change, but moss peat banks contain an unrivalled temporal record of past climate change on terrestrial plant Antarctic systems. We summarise the current understanding of climatic proxies and determinants of moss growth for contrasting continental and maritime Antarctic regions, as informed by 13C and 18O signals in organic material. Rates of moss accumulation are more than three times higher in the maritime Antarctic than continental Antarctica with growing season length being a critical determinant of growth rate, and high carbon isotope discrimination values reflecting optimal hydration conditions. Correlation plots of 13C and 18O values show that species (Chorisodontium aciphyllum / Polytrichum strictum) and growth form (hummock / bank) are the major determinants of measured isotope ratios. The interplay between moss growth form, photosynthetic physiology, water status and isotope composition are compared with developments of secondary proxies, such as chlorophyll fluorescence. These approaches provide a framework to consider the potential impact of climate change on terrestrial Antarctic habitats as well as having implications for future studies of temperate, boreal and Arctic peatlands. There are many urgent ecological and environmental problems in the Arctic related to mosses in a changing climate, but the geographical ranges of species and life-forms are difficult to track individually. Our goal was to translate what we have learned from the more simple systems in Antarctica, for application to Arctic habitats.

Plants and Soil Microbes Respond to Recent Warming on the Antarctic Peninsula

Annual temperatures on the Antarctic Peninsula, one of the most rapidly warming regions on Earth, have risen by up to 0.56°C per decade since the 1950s. Terrestrial and marine organisms have shown changes in populations and distributions over this time, suggesting that the ecology of the Antarctic Peninsula is changing rapidly. However, these biological records are shorter in length than the meteorological data, and observed population changes cannot be securely linked to longer-term trends apparent in paleoclimate data. We developed a unique time series of past moss growth and soil microbial activity from a 150-year-old moss bank at the southern limit of significant plant growth based on accumulation rates, cellulose δ(13)C, and fossil testate amoebae. We show that growth rates and microbial productivity have risen rapidly since the 1960s, consistent with temperature changes, although recently they may have stalled. The recent increase in terrestrial plant growth rates and soil microbial activity are unprecedented in the last 150 years and are consistent with climate change. Future changes in terrestrial biota are likely to track projected temperature increases closely and will fundamentally change the ecology and appearance of the Antarctic Peninsula.

Differing source water inputs, moderated by evaporative enrichment, determine the contrasting δ18OCELLULOSE signals in maritime Antarctic moss peat banks

AbstractOxygen isotope palaeoclimate records, preserved in moss tissue cellulose, are complicated by environmental influences on the relationships between source water inputs and evaporative conditions. We carried out stable isotope analyses of precipitation collected from the maritime Antarctic and cellulose extracted from co‐located Chorisodontium aciphyllum dominated moss peat bank deposits accumulated since 1870 A.D. Analyses of stable oxygen and hydrogen isotope composition of summer precipitation on Signy Island (60.7°S, 45.6°W) established a local meteoric water line (LMWL) similar to both the global MWL and other LMWLs, and almost identical to the HadAM3 isotope‐enabled global circulation model output. The oxygen isotopic composition of cellulose (δ18OC) revealed little temporal variation between four moss peat banks on Signy Island since 1870. However, δ18OC followed two patterns with Sites A and D consistently 3‰ enriched relative to δ18OC values from Sites B and C. The growing moss surfaces at Sites A and D are likely to have been hydrated by isotopically heavier summer precipitation, whilst at Sites B and C, the moss banks are regularly saturated by the isotopically depleted snow melt streams. Laboratory experiments revealed that evaporative enrichment of C. aciphyllum moss leaf water by 5‰ occurred rapidly following saturation (ecologically equivalent to post‐rainfall or snow melt periods). In addition to the recognized source water‐cellulose fractionation extent of 27 ± 3‰, such a shift would account for the 32‰ difference measured between δ18O of Signy Island precipitation and cellulose.

Peat bank growth, Holocene palaeoecology and climate history of South Georgia (sub-Antarctica), based on a botanical macrofossil record

Botanical macrofossil analysis of a more than 9000 years old, radiocarbon dated peat sequence of a moss peat bank from South Georgia, shows a clear evolution in the vegetation. Seven ecological phases could be distinguished and they can be interpreted in terms of climate development during the Holocene. Until 2200 years ago, Warnstorfia fontinaliopsis was the dominant moss species pointing to a wet environment. Lower numbers of this species in association with the presence of drier species are assumed to indicate drier periods, such as occurring between ca 6000–5200 and 4400–3400 cal yr BP. The most prominent and definitive vegetation change took place around 2200 cal yr BP. A Polytrichum–Chorisodontium moss peat bank was formed, which is still growing there today. The forcing mechanism for this vegetation change is thought to be a temperature decrease, rather than a precipitation decrease. This conclusion is mainly based on the fact that, today, moss peat banks have their optimal occurrence range in the maritime Antarctic, a region were the mean annual temperature is ca 4 °C lower than on South Georgia. The remarkable change in the moss bank vegetation at 2200 cal yr BP raises the question whether this moment was only a short climatic deterioration, or a definitive change to a cooler and wetter climate after a Holocene climatic optimum period.

Moss Bank

Moss Bank

Moss bank prepares for first withdrawals

Moss bank prepares for first withdrawals

Antarctic glacial history since the Last Glacial Maximum: an overview of the record on land

This overview examines available circum-Antarctic glacial history archives on land, related to developments after the Last Glacial Maximum (LGM). It considers the glacial-stratigraphic and morphologic records and also biostratigraphical information from moss banks, lake sediments and penguin rookeries, with some reference to relevant glacial marine records. It is concluded that Holocene environmental development in Antarctica differed from that in the Northern Hemisphere. The initial deglaciation of the shelf areas surrounding Antarctica took place before 10 000 14C yrs before present(BP), and was controlled by rising global sea level. This was followed by the deglaciation of some presently ice-free inner shelf and land areas between 10 000 and 8000 yr BP. Continued deglaciation occurred gradually between 8000 yr BP and 5000 yr BP. Mid-Holocene glacial readvances are recorded from various sites around Antarctica. There are strong indications of a circum-Antarctic climate warmer than today 4700–2000 yr BP. The best dated records from the Antarctic Peninsula and coastal Victoria Land suggest climatic optimums there from 4000–3000 yr BP and 3600–2600 yr BP, respectively. Thereafter Neoglacial readvances are recorded. Relatively limited glacial expansions in Antarctica during the past few hundred years correlate with the Little Ice Age in the Northern Hemisphere.

Colonization by lichens and the development of lichen-dominated communities in the maritime Antarctic

Three long-term studies of lichen growth and colonization have been undertaken at Signy Island, South Orkney Islands, in the maritime Antarctic. Small individual thalli of several crustose species and uncolonized plots on 12 fresh rock surfaces were photographically monitored at intervals of 3–4 years over a period of up to 20 years. The development of Ochrolechia frigida colonies on a regenerating moss bank, recently uncovered by a receding glacier, was similarly monitored. The results indicate that many lichens growing in sites enriched by nitrogenous compounds derived from populations of sea birds, have relatively rapid colonization and growth rates. Mean percentage increase in thallus area can be as high as 15–32% per annum in some nitrophilous saxicolous species (e.g. Acarospora macrocyclos, Xanthoria elegans and species of Buellia and Caloplaca), but as low as 0·4–4% in nitrophobous species ( Lecanora physciella, Lecidea sp., Rhizocarpon geographicum). Umbilicaria antarctica and Usnea antarctica also yielded data indicating high growth rates, with colonist plants reaching several centimetres after 20 years. Colonization by mixed assemblages of lichens of new rock surfaces can attain 40→90% cover after 20 years in nutrient-enriched sites, and even 20–25% in non-biotically influenced sites. Colonization by or increase in extant O. frigida on the regenerating moribund moss bank was also quite rapid. It is suggested that the ~exceptionally large thalli of several lichen species and the locally extensive dense lichen fellfield communities in the maritime Antarctic may be much younger than previously supposed.

Colonization by Lichens and the Development of Lichen-Dominated Communities in the Maritime Antarctic

Three long-term studies of lichen growth and colonization have been undertaken at Signy Island, South Orkney Islands, in the maritime Antarctic. Small individual thalli of several crustose species and uncolonized plots on 12 fresh rock surfaces were photographically monitored at intervals of 3–4 years over a period of up to 20 years. The development of Ochrolechia frigida colonies on a regenerating moss bank, recently uncovered by a receding glacier, was similarly monitored. The results indicate that many lichens growing in sites enriched by nitrogenous compounds derived from populations of sea birds, have relatively rapid colonization and growth rates. Mean percentage increase in thallus area can be as high as 15–32% per annum in some nitrophilous saxicolous species (e.g. Acarospora macrocyclos, Xanthoria elegans and species of Buellia and Caloplaca), but as low as, 0·4–4% in nitrophobous species (Lecanora physciella, Lecidea sp., Rhizocarpon geographicum). Umbilicaria antarctica and Usnea Antarctica also yielded data indicating high growth rates, with colonist plants reaching several centimetres after 20 years. Colonization by mixed assemblages of lichens of new rock surfaces can attain 40-&gt;90% cover after 20 years in nutrient-enriched sites, and even 20–25% in non-biotically influenced sites. Colonization by or increase in extant O. frigida on the regenerating moribund moss bank was also quite rapid. It is suggested that the exceptionally large thalli of several lichen species and the locally extensive dense lichen fellfield communities in the maritime Antarctic may be much younger than previously supposed.