MORPHOLOGICAL AND HYDROLOGICAL RESPONSES OF SOAN AND KHAD RIVERS TO IMPERVIOUS LAND USE IN DISTRICT MURREE, PAKISTAN.

The study was conducted during 2005 to 2009 in District Muree, Pakistan. Rapid degradation of watersheds due to soil erosion, deforestation, urbanization is the critical issue in high hill areas. Housing and infrastructure development, being the top priority of government is also impacting the health of watersheds; resultantly our dams are losing their capacity due to increased sedimentation. The study aimed at assessing the current magnitude and distribution of development in two important watersheds of Punjab. The assessment was carried out by correlating infrastructure development with soil erosion and regime of water in the channels. Impervious land use in Simly watershed is increasing at a pace of 1.91 % per year and presently it is 13.23 % of the total area. It has also been determined that at current pace of development, 16.84 % of the area in Simly will be under impervious land use by 2020. Based on the land use of the area, different channels in Simly stream system were categorized into urbanizing, agriculture and forest and main channel. The study revealed that the soil erosion is more in areas under impervious land use or where the land is disturbed due to developmental activities. The sediment load in different categories of channels was studied. It was found that sediment load in the urbanizing water channel was highest (26.03 g/l) followed by agriculture (8.86 g/l), and forest was the least (1.73 g/l) contributor of sediment in the channels. Water quality of the stream system has also been deteriorated. Turbidity and hardness was more in urbanizing as compared to other land use. [ABSTRACT FROM AUTHOR]