Climate-Growth Response Function of the Blue Pine (Pinus Wallichiana) in Galies Forest Division-Abbottabad, KP, Pakistan

Climate change is a global phenomenon manifested in rising temperature, erratic changes in precipitation and other climate variables. To assess such impacts, climate-growth response function of the Blue pine (Pinus wallichiana) was studied in Galies Forest Division -Abbottabad, Khyber Pakhtunkhwa, Pakistan, for the time period 1962-2011. Time function response and impacts of changing climate were estimated on the basis of annual ring-width and intra-ring wood formations. The results showed mean ring-width of 2.54±0.11 mm/annum with mean sensitivity and coefficient of variation of 0.38 and 19.50%, respectively. Overall, a decreasing trend was observed in ring-width. The largest mean ring-width was 3.33±0.31 mm, while the smallest ring-width was 1.85±0.27 mm. The mean intra-ring early wood formation was 75.56±0.21%, while the intra-ring late wood formation was 24.44±1.95%. The highest growth in ring-width and intra-ring early wood formation was recorded during 1962-71, while that of intra-ring late wood formation was recorded during 2002-11. The impact of maximum temperature and minimum temperature on ring width was negative and highly significant (p 0.01) and of precipitation positive and non-significant (p 0.05). The study showed a negative growth response of annual growth ring-widths and intra-ring early wood formation and a positive growth response of intra-ring late wood formation of Pinus wallichiana to rising temperatures. These results suggested that the use of ring-widths combined with intra-ring wood formations enables better assessment of impacts of climate change on tree growth. It is recommended that climate change projections and scenarios may be made an integral part of Forest Management Plans for making realistic wood volume and yield estimates.