During the first six months of soil burial tests the average air temperature was equal to 3.4 ��C, than between 7 and 12 months, average air temperature increased to 15.4 ��C.

During the first six months of soil burial tests the average air temperature was equal to 3.4 ��C, than between 7 and 12 months, average air temperature increased to 15.4 ��C.