Phytoecological distribution of plant communities of two dominant tree species and their dendrochronological analysis in Jhika Gali, Murree, Pakistan.

The research work is focused on dendroecological potential of Pinus roxburghii (Sarg.) and Pinus wallichiana (A. B. Jacks.) in Jhika gali of murree. Age, growth rate, height, diameter at breast height (dbh), and phytosociological attributes of these two pine species were determined. Increment borers were used to obtain samples from study site. 50 samples from each species were obtained. In P. roxburghii the growth rate varied between 0.93 cm/year to 0.58 cm/year with Dbh 193 and 189.5 cm, respectively. Height was measured in between 30.17 and 18.6 m. In first stand of P. roxburghii maximum growth rate was 0.93 inches/year and minimum in growth rate in second stand was 0.58 cm/year with Dbh 193 and 189.5 cm, respectively. There was an inverse correlation between growth rate and dbh, but growth rate and height it was direct. In P. wallichiana growth rate varied between 1.3 cm/year with dbh 64 cm and 0.41 cm/year with dbh 105.1 cm. The relationship observed between height and growth rate was directly proportional in P. wallichiana, while it was inverse between dbh and growth rate. In Phytosociology, 92 species were collected belonging to 44 different families. IVI values of various species varied between minimum 0.99 and maximum 2.65. TWINSPAN is indicating the diverse nature of plant communities with diverse nature of grouping. Group I (G 1), Group II (G 3) has biodiversity in some of stands while Group II (G 2) has greatest biodiversity with five subgroups and subsequent associations. [ABSTRACT FROM AUTHOR]