VEGETATION MAP OF THE BATURA VALLEY (HUNZA KARAKORUM, NORTH PAKISTAN)

摘要

An annotated medium-scale vegetation map (1:60000) of the Batura Valley, Hunza Karakorum (Pakistan, Northern Areas) is presented. The study area covers ca. 700 km~2 (between 36 deg 27'N/74 deg 30'E and 36 deg 40'N/74 deg 54'E) along the Batura Glacier, one of the largest outlet glaciers outside the polar regions, and ranges in altitude from 2,450 m (Passu Village) to 7,785 m (Batura I). The upper limit of vascular plant life is situated at 5,000-5,200 m. Due to the subtropical latitude and generallyarid climate, the Batura Valley presents a desert or steppe aspect. Vast expanses of glacial ice, rock and mobile scree are virtually devoid of plant life along the elcvational gradient. Vegetation covers only ca. ten percent of the study area and is comprised of ca. 380 vascular plant species. 26 vegetation units are mapped. Open herbaceous or dwarf-shrub vegetation predominates. Fragments of forest, denser scrub and turf communities arc confined to small areas. Despite its generally depauperate, fragmented and patchy character, the vegetation of the Batura Valley displays considerable local diversity and reflects a huge elevational gradient, ranging from warm-temperate (submontane) to alpine and subnival situations. The phytogeographic and ecologicaloverview is augmented by a discussion of the present status and future prospects of the human impact on the vegetation of the Batura Valley. The human impact on the vegetation cover, mainly through grazing of domestic stock, is generally high. However,the exact nature and specific effects of anthropo-zoogenic interference vary and are also subject to recent socio-economic changes in the region.