Seasonal variability of the leaf area index of spruce forest of different age in the Western Tatra Mountains

Year, pages: 2018, 210 - 219

The article presents results of the leaf area index (LAI) assessment by means of hemispheric photography and the HemiView software in the mountain catchment of the Jalovecký creek in period June–September 2018. The photographs were taken every two weeks at 10 sites located close to each other; all sites were photographed within 1.5–2 hours. The photographs were masked by a circular mask to remove the effects of the surrounding slopes and decrease the influence of wood. LAI was defined as half of the total leaf area per unit ground area and the values were not corrected with clumping index. Seasonal variability of point values at individual stands expressed by coefficient of variation was 3% to 10%. Point LAI values in the 55–145 years old forest varied approximately between 4,5 and 6 (median 5.2). Median LAI of the 35-years old spruce forest was 6.4. Presence of beech slightly increased LAI (by about 0,5). The uncertainty (error) in the LAI assessment was evaluated by comparison of the values obtained from the same site using the photographs taken on the same day (with time shift not greater than 3 hours) or on two successive days. The uncertainty defined this way reached was in most cases within 0.3–0.7. As expected, the greatest varaibility was found within the stand. This stand variability of LAI was determined from five photographs taken at each stand on 18 September and the coefficients of variation varied between 4%–34% (average 14%). Median LAI calculated from five photographs taken at the stand varied at most sites between 6 and 7 (in the 35-years old forest it was 7.8).

Danko, M., Holko, L., Škvareninová, J., Škvarenina, J. 2018. Seasonal variability of the leaf area index of spruce forest of different age in the Western Tatra Mountains. In Acta Hydrologica Slovaca, vol. 19, no.2, pp. 210-219. 2644-4690.

Danko, M., Holko, L., Škvareninová, J., Škvarenina, J. (2018). Seasonal variability of the leaf area index of spruce forest of different age in the Western Tatra Mountains. Acta Hydrologica Slovaca, 19(2), 210-219. 2644-4690.