lundi 27 décembre 2010

Some data from the transects

1) Transect on the Northern slope of the Utsteinen nunatak
I can distinguish three types of ecotopes on this granite nunatak:
1.The rocks with water (top of Utsteinen at the edge of the snowbanks, or the foot of Utsteinen). Coverage by Biological Crusts is 7-44% (low and medium coverage). The presence is 41/50 “on-point” BSC occurrences in 50 transect points, that means 82%.
2.The rocks without water (middle part of the slope with too high wind
speed and low deposition of snow). Coverage by BSC is 0-0.3% (low), and the presence is 2 out of 30 transect points, thus 6.6%.
3.The areas near bird's nests. The coverage is 0-1% (low), and the presence is 9 out of 30 transect points, that means 30%.

2) Transects on the Northern and Southern slopes of the Teltet nunatak
However, when we have done the same transects on the Northern and Southern slopes of the Teltet nunatak, which is made of gneiss, I did not manage to find any Biological Soil Crust!
The very weathered rocks of the Teltet nunatak

These results show that the type of rocks is very important for the development of BSCs. Ecotopes with similar conditions on Teltet and Utsteinen have absolutely different numbers and coverages of BSCs.
I have also collected and replaced the temperature and humidity loggers on Teltet. Probably, I will be able to replace them again before we'll leave, so we'll have data from this summer also.

Aucun commentaire:

Enregistrer un commentaire