Spatial patterns of vegetation with underlying soil properties prevailing along drain side areas in Islamabad City.

Present study was conducted in Islamabad one of the rapidly growing city of Pakistan the and aimed to identify vegetation communities prevailing along drain sides and their relationship to the underlying soil properties. A total of 186 quadrats were recorded which covered the whole stretch of drains passing throughout the city. A total of 18 edaphic properties were determined in acid extractable surface soils of each quadrat. Two way indicator species analysis (TWINSPAN) identified two major communities (Broussonetia-Populus and Panicum-Conyzanthes community types). Amongst weeds, species such as Cynodon dactylon, Malvestrum coromendilianum and Parthenium hysterophorus were more frequent. Detrended Correspondence Analysis (DCA) identified environmental gradients to vegetation distribution. First ordination axis demonstrated hierarchical vegetation gradient shift of species from trees to herbs due to transformation of land from open to constructed land whereas, second axis highlighted the influence of invasive species. The distribution pattern of vegetation influenced by soil physico-chemical properties was demonstrated by Canonical Correspondence Analysis (CCA) which explained a total of 11.25% variance. The results conclude that human disturbance has affected environmentally designed vegetation patterns. It is therefore necessary to take into account trends like human influence, land abandonment and land use for the maintenance and conservation of vegetation.