A Synthesis of Glacial-Interglacial Paleoenvironmental Records from Lake Sediments of Schirmacher Oasis, East Antarctica

2022 ◽  
pp. 127-140
Author(s):  
Anish Kumar Warrier ◽  
B. S. Mahesh ◽  
Joju George Sebastian ◽  
A. S. Yamuna Sali ◽  
Rahul Mohan
Keyword(s):  
Lake Sediments ◽  
East Antarctica ◽  
Schirmacher Oasis

Rare and new for Antarctica species of algae from the continental waterbodies of Schirmacher Oasis

2021 ◽  
Vol 55 (2) ◽  
pp. 335-347
Author(s):  
S. V. Smirnova ◽  
T. V. Safronova ◽  
A. F. Luknitskaya ◽  
O. N. Boldina
Keyword(s):  
East Antarctica ◽  
Algal Flora ◽  
Schirmacher Oasis ◽  
The Antarctic

One rare (Dinobryon cylindricum) and two new (Gonium pectorale, Staurastrum orbiculare) for the Antarctic algal flora species were found in the waterbodies of Schirmacher Oasis (East Antarctica). Their locations are described. Data on morphology, ecology and distribution of the recorded species are summarized.

scholarly journals Meltwater flux and climate change record of last 18.5 ka from Schirmacher Oasis, East Antarctica

Polar Science ◽  
2018 ◽  
Vol 18 ◽  
pp. 135-141 ◽  
Author(s):  
Pawan Govil ◽  
Abhijit Mazumder ◽  
Raghu Ram ◽  
Dhruv Sen Singh ◽  
Syed Azharuddin
Keyword(s):  
Climate Change ◽  
East Antarctica ◽  
Schirmacher Oasis

scholarly journals Semiautomated Detection and Mapping of Vegetation Distribution in the Antarctic Environment Using Spatial-Spectral Characteristics of WorldView-2 Imagery

2019 ◽  
Vol 11 (16) ◽  
pp. 1909 ◽  
Author(s):  
Shridhar D. Jawak ◽  
Alvarinho J. Luis ◽  
Peter T. Fretwell ◽  
Peter Convey ◽  
Udhayaraj A. Durairajan
Keyword(s):  
Feature Extraction ◽  
High Resolution ◽  
East Antarctica ◽  
Superior Performance ◽  
Matched Filtering ◽  
Vegetation Distribution ◽  
Important Indicator ◽  
Larsemann Hills ◽  
Validation Experiment ◽  
Schirmacher Oasis

Effective monitoring of changes in the geographic distribution of cryospheric vegetation requires high-resolution and accurate baseline maps. The rationale of the present study is to compare multiple feature extraction approaches to remotely mapping vegetation in Antarctica, assessing which give the greatest accuracy and reproducibility relative to those currently available. This study provides precise, high-resolution, and refined baseline information on vegetation distribution as is required to enable future spatiotemporal change analyses of the vegetation in Antarctica. We designed and implemented a semiautomated customized normalized difference vegetation index (NDVI) approach for extracting cryospheric vegetation by incorporating very high resolution (VHR) 8-band WorldView-2 (WV-2) satellite data. The viability of state-of-the-art target detection, spectral processing/matching, and pixel-wise supervised classification feature extraction techniques are compared with the customized NDVI approach devised in this study. An extensive quantitative and comparative assessment was made by evaluating four semiautomatic feature extraction approaches consisting of 16 feature extraction standalone methods (four customized NDVI plus 12 existing methods) for mapping vegetation on Fisher Island and Stornes Peninsula in the Larsemann Hills, situated on continental east Antarctica. The results indicated that the customized NDVI approach achieved superior performance (average bias error ranged from ~6.44 ± 1.34% to ~11.55 ± 1.34%) and highest statistical stability in terms of performance when compared with existing feature extraction approaches. Overall, the accuracy analysis of the vegetation mapping relative to manually digitized reference data (supplemented by validation with ground truthing) indicated that the 16 semi-automatic mapping methods representing four general feature extraction approaches extracted vegetated area from Fisher Island and Stornes Peninsula totalling between 2.38 and 3.72 km2 (2.85 ± 0.10 km2 on average) with bias values ranging from 3.49 to 31.39% (average 12.81 ± 1.88%) and average root mean square error (RMSE) of 0.41 km2 (14.73 ± 1.88%). Further, the robustness of the analyses and results were endorsed by a cross-validation experiment conducted to map vegetation from the Schirmacher Oasis, East Antarctica. Based on the robust comparative analysis of these 16 methods, vegetation maps of the Larsemann Hills and Schirmacher Oasis were derived by ensemble merging of the five top-performing methods (Mixture Tuned Matched Filtering, Matched Filtering, Matched Filtering/Spectral Angle Mapper Ratio, NDVI-2, and NDVI-4). This study is the first of its kind to detect and map sparse and isolated vegetated patches (with smallest area of 0.25 m2) in East Antarctica using VHR data and to use ensemble merging of feature extraction methods, and provides access to an important indicator for environmental change.

Lichen synusiae in East Antarctica (Schirmacher Oasis and Larsemann Hills): substratum and morphological preferences

2011 ◽  
Vol 1 (2) ◽  
pp. 65-77 ◽  
Author(s):  
Himanshu Rai ◽  
Roshni Khare ◽  
Sanjeeva Nayaka ◽  
Dalip Kumar Upreti ◽  
Rajan K. Gupta
Keyword(s):  
Growth Form ◽  
Environmental Gradients ◽  
Hierarchical Cluster ◽  
Terrestrial Ecosystems ◽  
Growth Conditions ◽  
East Antarctica ◽  
Plant Distribution ◽  
Larsemann Hills ◽  
Schirmacher Oasis ◽  
Study Sites

Antarctic terrestrial ecosystems experience some of the most extreme growth conditions, where plant distribution is determined by favourable environmental gradients of temperature and moisture along with micro-topography of habitats. Lichens are among the most tolerant symbiotic organisms which constitute dominant component in the terrestrial biota of Antarctica. There are various studies dealing with patterns of lichen diversity of various regions of Antarctica are done but in east Antarctica such studies are scanty. Lichen synusiae of Schirmacher Oasis and McLeod Island, Larsemann Hills, East Antarctica were studied in order to determine their morphological and substratum affinities. The Lichen synusiae of the study sites was represented by 71 species, 24 genera and 13 families in Schirmacher Oasis and 27 species, 18 genera and 10 families in McLeod Island, Larsemann Hills. Hierarchical cluster analysis of lichen communities on the basis of growth form diversity and substratum occurrence showed that crustose growth form and saxicolous (on rock, stones and moraines) habitat were the most preferred, in both study sites. The study presents a representative account of morphological and substratum preference patterns in lichen synusiae of east Antarctica, which can be of fundamental importance for future lichenological investigation in the region.

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