Comparative Study of Climate Change and its Impact on Ring-Widths of Spruce (Picea smithiana) at Kalam and Kaghan Forest Divisions, Khyber Pakhtunkhwa, Pakistan

This study was conducted in Kalam Forest Division (KFD) and Kaghan Forest Division (KaFD), Khyber Pakhtunkhwa, Pakistan, with the objectives to assess the climate regimes and changes thereof during the period 1965-2015, and their impacts on ring-widths of Spruce (Picea smithiana), along with comparison of the results inter se the two Forest Divisions. Results indicated that KFD and KaFD had significantly different climate regimes of temperature and precipitation. Mean annual maximum and minimum temperatures and mean annual temperature at the two Forest Divisions during 1965-2015 significantly increased, while mean annual precipitation significantly increased in KaFD, but non-significantly decreased in KFD. Mean values of ring-widths of Spruce at KFD and KaFD during 1965-2015 were 1.36±0.02 mm and 1.48±0.02 mm and changes thereof – 0.11 mm and – 0.13 mm, respectively, showing a decreasing trend. The difference in the ring-widths and changes therein in the two Forest Divisions were significant (p 0.01). Correlation of ringwidth with temperature precipitation and response functions of Spruce in KFD and KaGD for the period 1965-2015 indicated similar patterns, and were significantly (p 0.01) negative with temperature, but nonsignificant (p 0.05) positive with precipitation. The values of R2 for ring widths were high, indicating a good fit of the linear models.