Life span of needles of Pinus mugo Turra: effect of altitude and species origin

The needle life span of evergreen coniferous trees is a species-specific trait but can be also affected and modified by environmental conditions. On the basis of field observations of needle life span during three periods in two populations of Pinus mugo in the Tatra Mts (altitude: 1600–1700 m) and Sudety Mts (altitude 830–1420 m), 11 populations from various altitudes we concluded that: 1) within the same population needle life span remained the same over the three periods of observations, 2) needle life span in the Tatra Mts is about 1 year longer than in the Sudety Mts, ranging from 5.5 to 5.9 years and 3) needle life span in the Sudety Mts increases significantly with the altitude of the population. The longer life span of needles in the Tatra Mts may be specific for the population, i.e. it may be due to a different population origin (another Pleistocene centre of the species), and the shorter life span of needles noted in the Sudety Mts may be due to higher soil pollution in this region.