查看更多>>摘要：This study reports on the multivariate analysis of the vegetation of Hindukush Range in Pakistan, concentrating on the structure and regeneration potential of Monotheca buxifolia and associated tree species. Twenty stands at different locations in the Dir District of the Hindukush Range in Pakistan were chosen for the study. A point centered quarter method for trees and 5 m × 5 m size quadrats were used for the sampling of understorey vegetation, including shrubs, seedlings, and saplings, respectively. The underlying group structure in vegetation was exposed by an agglomerative clustering technique, while major Wends were disclosed by DCA ordination. Size class structure and regeneration potential of M. buxifolia and associated Wee species were also examined, which reflects the future Wend of species and, consequently, the forests where they dominate. The relationships between environmental factors and vegetation were investigated.The arboreal vegetation was mostly dominated by broad leaved species including Monotheca buxifolia, Olea ferruginea, Acacia modesta, Punica granatum, Quercus baloot, and Ficus palmata. Among the understorey vegetation, the abundant species were Dodonea viscosa, Justicia adhatoda, Otostegia limbata, Indigofera gerardiana, Plantago lanceolata, Rumex dentatus, Marrubium vulgaris, Fragaria nubicola, Geranium rotundifolium, Daphne oleoides, Solanum nigram, Ajuga bracteosa, Oxalis corniculata seedlings of Monotheca buxifolia, Quercus baloot, and Punica granatum. At the seedling and sapling stage, the maximum number was observed for Monotheca buxifolia (27±5.75 and 38±7.1), followed by Quercus baloot (18±2.2 and 12±1.0) and Olea ferruginea. As far as regeneration status is concerned, 34% species showed good regeneration, 50% species were facing the problem of poor regeneration while, and only 16% species were not regenerating. Five groups of tree vegetation that emerged from Ward's cluster analysis could readily be superimposed on DCA ordination. These groups were associated with particular elevation and, to a lesser extent, with edaphic variables, such as pH and nutrients. Some of the topographic and edaphic variables, such as soil nutrient, showed significant or weak linear relationships with one or more ordination axes. The size class structure of M. buxifolia and associated tree species for individual stands exhibited a few gaps. Relationships between density and basal area were significant, but the density and basal area with altitudinal and slope gradient showed an insignificant relation. Some recommendations are outlined for future research and sustainable management of these forests species.
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