Stable nitrogen isotopes (d15N) in thalli of arid vagrant lichen Xanthoparmelia camtschadalis across an altitudinal gradient of the Khangai Plateau of Mongolia

The d(15)N values of stable nitrogen isotopes were determined in samples of organic matter (OM) of thalli of vagrant lichen Xanthoparmelia camtschadalis collected across 13 altitudinal levels within the range of 1550-3250 m above sea level of both steppes and highland meadows of the Khangai Plateau of Mongolia. No correlation between the d(15)N values of lichen OM and the altitude range was detected at the regional scale. However, at a local scale including vegetation type, botanical-geographical area of Khangai, and mountain slope, the amount of the N-15 heavy isotope in lichen OM was found to be decreased with an altitude increase.