DOI: 10.5285/8a885e6c-3a27-4cd7-850a-1ac1b9f89576
title: Mapping of the extent of vegetation patches on Leonie and Anchorage Islands in Ryder Bay, Antarctica in 2007

description: A hand-held Garmin GPS was used to map vegetation patches on Leonie and Anchorage Island in February 2007. Discrete patches of vegetation were walked round, and the recorded track saved. The aim of the data collection was to provide some ground truthing data for vegetation NVDI (Normalized Difference Vegetation Index) ratios calculated from satellite data. Funding: UK Natural Environment Research Council (core funding to the British Antarctic Survey).
description: Two islands in Ryder Bay, Leonie Island and Anchorage Island, were chosen as good locations to ground truth the NVDI ratios. Leonie Island is a very steep island, reaching 500 m in height and deglaciated on the North side. It has distinct patches of green vegetation including the flowering plants, Deschampsia antarctica and Colobanthus quitensis, and a variety of bryophyte species. These patches occur on cliff terraces, mainly at altitudes of less than 100 m. Anchorage Island, in contrast, has a maximum altitude of 54 m and is largely unvegetated at altitudes of less than 20 m, and lichen-covered at higher altitudes. It has much less green vegetation, with a couple of fairly small bryophyte-dominated patches (only 14 moss species and one liverwort species have been recorded there), and a single grass-dominated patch. The tops of the cliffs are lichen-covered predominantly by Usnea spp and Umbilicaria antarctica. A hand-held Garmin GPS was used to do the ground truthing by walking round discrete patches of vegetation and saving the recorded track. Leonie Island was visited on 9th February 2007 when the deglaciated part of the Island was walked along and all large patches of reasonably continuous green vegetation were mapped. A few small patches (less than 10 m2) at high altitudes and difficult to access were ignored. One large discrete patch on particularly steep cliffs was difficult to walk round, so just the top edge of the patch was mapped. Anchorage Island was visited on 10th and 13th February 2007. Here, to enable the NVDI ratios of moss and lichen dominated areas to be compared, two discrete green patches of moss vegetation and two patches of lichen vegetation were mapped. The second of the lichen tracks included a small, disparate, area dominated by grasses, but no areas dominated by mosses. Finally, an area of algal vegetation on one of the beaches was mapped to see whether the remote sensing data was likely to pick up algal vegetation. A Readme file is attached for additional information about start and end GPS positions, as well as information on the date and length of individual tracks.
description: Hand held Garmin GPS.
description: Readme: For Track 4, the start and end positions in the Readme are the last recorded GPS positions in the .csv file. For Track 6, the end coordinate in the Readme is the last recorded GPS position in the .csv file. Data: Could not get around all of Track 4: it extended down steep cliffs all the way to the sea. A few scattered patches also not surveyed high up towards scree cliffs. Track 8 positions went a bit wide on one side of the edge of the patch due to fur seals. Further mapping on Anchorage generally was curtailed due to blizzard conditions.