Lichenometry on Adelaide Island, Antarctic Peninsula : size-frequency studies, growth rates and snowpatches
This paper presents new lichenometric population data from the Antarctic Peninsula (67°S), and describes a new approach to lichen growth-rate calibration in locations where dated surfaces are extremely rare. We use historical aerial photography and field surveys to identify sites of former perennial snowpatches where lichen populations now exist. As an independent check on lichen mortality by snowkill, and the timing of snow patch disappearance, we use a positive-degree day (PDD) approach based on monthly climate data from Rothera Research Station. We find that maximum growth rates for lichens <40 mm in diameter on Adelaide Island are around 0.8 mm/yr. Furthermore, we propose that our combined methodology may be more widely applicable to the Polar Regions where the construction of lichenometric dating (age-size) curves remains a problem.
Just 16 overs of play were possible as Ireland and Australia A were both frustrated by the heavy rain at Stormont on day two. Press Association That did not stop opening bowler Max Sorensen from completing his maiden five-wicket haul for the hosts in the 72 minutes of play as Australia made it to 312 for nine at the halfway point of the encounter, with star man Steve Smith out for 133. James Pattinson, who is predicted to give England fits with his pace bowling in the upcoming Ashes series, helped the tourists recover from 139 for six on Friday, but he also perished having made a valuable 66. Smith and Pattinson had rescued Australia from a potentially embarrassing episode in Belfast and the pair looked set to frustrate Ireland even further until the former was out in the 12th over of the day, edging behind an excellent delivery from Trent Johnston to bring an end to an innings that contained 19 fours and a six. Johnston’s breakthrough also halted the seventh wicket partnership of 157 made in 42.5 overs before Ireland finished the day with a spring in their step after claiming two wickets in the final two overs. First, Pattinson was caught behind to give Sorensen his five-for, with the South African-born seamer then taking the catch in the next over after Nathan Lyon had loosely driven at Johnston, who finished the day with figures of four for 68.