Climate influence on radial increment of oak (Quercus SP.) in central Poland

The study investigates the influence of climate conditions on radial increment of oak, with special concern to the situations when analysed trees formed conspicuously wider or narrower tree-rings. The research material was collected in four locations in central Poland within natural range of pedunculate and sessile oaks. The elaborated residual chronologies were correlated with CRUTS 2.1 climate data. The analyses included thermal and pluvial conditions spanning from April of the year prior to ring formation to September of the current growth year. Special interest was paid to simple water ability index that combined both temperature and precipitation during the vegetation season. Additionally, pointer year analysis was carried out to determine situations when conspicuously smaller or larger increment was formed. Investigated chronologies cover the period of 1927?C1992 (?ochów), 1845?C1992 (P?o??sk), 1868?C1992 (Pu?tusk), and 1796?C1992 (Soko?ów). The analysed oaks from sites in central Poland exhibit growth patterns comparable with those known form previous studies concerning that species, where influence of precipitation (higher and positive) and temperature (negative) have been observed. Extreme growth reactions expressed by negative and positive pointer years turned to present high dependence of analysed oak?? growth on water availability during vegetation season.     

Tree ring analysis as an indicator of environmental changes caused by tourist trampling — A potential method for the assessment of the impact of tourists

This paper shows that tree-ring trends might be used for the assessment of the intensity of trampling along touristic tracks in the forests. The study aims at determining the effects of trampling, on the dynamics of annual increments in trees subject to pressure from hiking tourism. The studies were conducted at a spruce stand in the Tatra Mts., on sections of different trails. Within each trail, four transects were determined. Transects include the zones with damage from trampling and the un-affected areas, treated as a reference zones. Selected trees growing in both zones were sampled by coring and the core samples were used to develop sequences of annual increment widths. Next, the dynamics of increments in trees growing in the tourist zone and the reference zone were compared. The decrease in the annual increments was significantly more rapid in trees growing directly along the trail that those in trees deep in the forest stand in one locality. This finding may testify the adverse effects of hiking along tourist routes on the radial increments in trees in the neighbourhood of the trails. The results of the study indicate that the impact of trampling in the form of soil compaction and mechanical damage to root systems of trees may, to some extent, be compensated by better light access and lessened competition experienced by trees growing along the edges of hiking trails. Tree-ring analyses might be an efficient alternative for assessment of tourism intensity conducted by the other methods.