Influence of snow damage on aerodynamic characteristics of a spruce stand

Abstract

Influence of snow damage on aerodynamic characteristics of a spruce stand was investigated during the growing seasons 2005 and 2006 before and after the winter 2005/2006 that caused damage to the forest. Wim this aim, the wind speed profiles measured in and above the investigated forest stand were analyzed. This forest is situated in the Experimental Ecological Study Site Bílý Kříž in the Moravian-Silesian Beskydy Mountains, the Czech Republic. The experimental site consists of two plots with Norway spruce monocultures with different stand densities. In the growing season 2005, the mean tree height was 11.9 m on the "dense" plot (Fd; a density of 2,044 trees/ha) and 11.0 m on the "sparse" one (Fs; a density of 1,652 trees/ha). The measurements of wind speed profile were realized at six levels on 26-m-high towers situated near the centre of each plot. The winter 2005/2006 was characterized by continuous snow cover (from November 2005 to April 2006) with a high water value in the investigated locality. The damage to the forest caused by this snow blanket was noticeable, mainly in Fd. The stand density decreased by about 29% on Fd and by about 14% on Fs plot. It witnesses entirely new airflow conditions within and over this forest stand and connected changes in its aerodynamic characteristics.