The major environmental factor correlated with variation in cone vegetation is the disturbance dynamics as determined by the structure of the soil profile active cones (with sand at the surface) are colonized by different species as compared with non-active cones (with surface covered by humus sediments). To express mesoclimatic differentiation among the cones within the rocky area, the potential insolation was calculated from the horizon angular height and the likelihood of thermal inversions was estimated by the height of the cones above the valley bottom.
Soil profiles were recorded at the upper, centre and bottom parts of the cones. Vegetation was recorded both at the whole-cone level and at the within-cone level the latter was approached by means of a transect of small squares along each cone. These cones (usually 3-12 m long) are formed by the accumulation of sand at the foot of sandstone rocks and are subject to frequent disturbance by the transport of sand. A system of sand talus cones in a small forested rocky sandstone area was investigated to determine the importance of disturbance-related dynamics and mesoclimate to vegetation differentiation.
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