Message - 7th IAL Symposium

The 7 th International Association for Lichenology Symposium 2012
(3B-2-P7) Submission ID: IAL0094-00001
VARIATIONS IN THE GROWTH RATES OF LICHENS OVER THE COURSE OF A LONG-TERM
INVESTIGATION IN THE TROPICAL FORESTS AT KHAO YAI NATIONAL PARK, THAILAND
Wannalux B. 1 , Polyiam W. 1 , Boonpragob K. 1
1 Biology, Ramkhamhaeng University, Bangkok, Thailand
Long term monitoring of the growth of lichens in five types of tropical forests in Thailand was conducted
between 1999 and 2010 at Khao Yai National Park. The objectives of this study were to observe (1) the longevity
of lichen thalli in a tropical climate; and (2) variations of the growth rates of lichens in various types of tropical
forests under different climate. A total of 73 species with 306 thalli were monitored, of which 45 were crustose
and 28 were foliose species composing of 146 and 160 thalli, respectively. After twelve years only 23% of the
observed thalli remained intact with 32% of the crustose and 14% of the foliose lichens. The largest proportions
of intact thalli of both crustose and foliose were observed under dry dipterocarp forest conditions at 58% and
31%, respectively. The average growth rate for crustose lichens was 2.8 mm/year with a range between 0.29
and 7.89 mm/year, whereas those of foliose lichens was 6.36 mm/year with a range between 0.11 and 17.43
mm/year. Lichens in the five forest types differed in average growth rates. The lowest rate was observed under
dry evergreen forest and with the highest growth rate being noted under tropical rain forest. In contrast, the
growth rate of foliose lichens varied from 1.24 to 14.53 mm/year with the lowest rate being found under tropical
rain forest and the highest rate measured under lower montane forest. Average growth rates of the crustose
lichens measured after two, four, six, eight, ten, and twelve years, respectively, fluctuated at 1.30, 2.46, 2.52,
2.59, 2.03 and 2.28 mm/year, while those of the foliose thalli were 6.04, 5.58, 4.78, 5.89, 6.24 and 6.36 mm/
year. This study demonstrated that lichen thalli in a sunny and dry habitat in the tropics live longer than in shady
warm-wet places. Variations in the growth rates at differing ecosystems and over the years reflected variability of
climatic conditions. These results require amplification and must be further addressed for the sake of conserving
biodiversity under a changing climate.
(3B-2-P8) Submission ID: IAL0101-00001
LICHENS AS BIOMARKERS FOR DEW AMOUNT AND DURATION IN THE NEGEV DESERT
Temina M. 1 , Kidron G. J. 2
1 Institute of Evolution, University of Haifa, Haifa, Israel
2 Institute of Earth Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
We studied the lichen diversity on cobbles at 18 stations located within four aspects of a second order
drainage basin near Sede Boqer at the Negev Highlands, Israel where dew was found to be the main water
source for lichens. At each station 10 cobbles were randomly chosen and the lichen composition and structure
were investigated and compared to the dew amount and duration that characterize each station. The stations
were grouped into 5 clusters that showed a close link with the dew moisture regime. Lichen distribution pointed
to species which can serve as biomarkers for dew amount and especially for dew duration. The data implies
that lichens can provide information regarding the dew regime at meso-habitats where no microclimatic data are
available.
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