A multivariate analysis of the vegetation of Cedrus deodara forests in Hindu Kush and Himalayan ranges of Pakistan: evaluating the structure and dynamics

Authors: MOINUDDIN AHMED, SYED SHAHID SHAUKAT, MUHAMMAD FAHEEM SIDDIQUI

Abstract: This investigation focuses on the multivariate analysis of the vegetation of the Hindu Kush and Himalayan ranges of Pakistan, concentrating on the dynamics of Cedrus deodara (Roxb. ex D.Don) G.Don. The study includes 47 stands from 23 different locations in the Himalayan region of Pakistan. The point-centred quarter method and 1.5-m radius circular plots were used for the sampling of tree and understorey vegetation, respectively. The size, age structure, and growth rates of Cedrus deodara were also examined in order to trace its dynamics, and an attempt was made to determine the relationships between environmental factors and vegetation. The quantitative distribution of understorey vegetation was also assessed as a way of evaluating the floristic association of the forests. The underlying group structure in the vegetation was exposed using Ward's clustering technique. Results of the cluster analysis showed that 6 groups of vegetation could readily be superimposed on DCA ordination. The vegetation was potentially continued. Among the environmental variables, factors such as elevation, pH, organic matter of soil, total nitrogen, and magnesium showed significant correlations with ordination axes. The size-class structure of Cedrus deodara exhibited many gaps. In most stands, Cedrus deodara exhibited ample recruitment, and relationships between diameter, age, and growth rate were significant in many stands. The study also proposes some recommendations for the maintenance and proper management of these forests.

Keywords: Cluster analysis, DCA ordination, vegetation description, dendrochronology, management plan, Cedrus deodara

Full Text: PDF