Population Structure and Dynamics of Juniperus excelsa in Balouchistan, Pakistan

1990

S. 271-276

3 Abb., 3 Tab., 24 Lit. Ang.

Unselbständiges Werk

200054711

Journal of Vegetation Science 1990 : Official organ of the international Association for Vegetation Science ; 1/2, S. 271-276

60 monospecific stands of Juniperus excelsa were sampled at four locations in Balouchistan. Density, basal area and height of individuals were recorded. Soils were analysed for selected physical and chemical characteristics and the degree of disturbance due to logging and burning was noted. The density of juniper trees (>6 cm dbh) ranged from 56 to 332 stems/ha (average 174 stems/ha). Higher densities were recorded for relatively undisturbed stands and on west facing slopes. Density of seedlings and saplings (>6 cm dbh) was strongly correlated with tree density and tree basal area. Among the edaphic variables CaCO3 was correlated with juniper density and basal area. Diameter distributions within stands were mostly skewed and unimodal with gaps appearing in large size classes. The male to female ratio was close to 1. Cross-sections of 16 trees were used to determine age and growth rate. Number of rings in trees with 20 to 30 cm dbh ranged from 95 to 221. Diameter and age were not related. Mean annual diameter increment ranged from 6 to 16 yr/cm. It concluded that size class caps and low seedling/sapling densities are the consequence of anthropogenic disturbance.