Analytical Hierarchy Process Application in Urban Sustainability Indicators Prioritization

Abstract

Deforestation has an impact on the quality of water flo wing through the watershed and alters the discharge, chemical and physical properties of water. This paper presents the effect of deforestation on water quality, in particular on physical and chemical characteristics of water and evaluates the community based watershed management s chemes in Buyhang micro watershed. The quality of water is assessed on the basis of laboratory analysis of various parameters by using weekly grab samp ling technique fro m three alternative land uses and in depth assessment of farmers' needs, priorities, an d conservation practices. The farmers' primary concerns are food security and sustained productivity. Soil erosion is not seen as a problem in the Cienda commun ity and currently still seems to reflect stable conditions. The perception and appreciation of people towards the function of forest ecosystems is limited. People are continuously changing the forest area for abaca plantations, rice fields, and other agricultural crops in very steep slopes. There is only 0.97 ha of refo restation activity in the watershed. Most people judge the quality of water by its aesthetic properties of colour, taste, odour and turbidity. Except the agricultural water samp les, the other two samp les appeared colourless through visual observations. The water fro m undisturbed forest area is palatable and all are free o f odour. The pH values of the water samples ranged with in standard values. Total hardness was trace except one sample fro m agricultural land. Turbidity was found to be less and ranging from 5 to 22 FTU. Sediment is recorded fro m agricultural water samples and higher during peak flow. The highest concentrations of PO4 - were measured fro m the forest water samples. The mean Ca ++ concentrations ranged from 10 to 11.6 mg/ L. There is no significant difference between the three water samples in Mg ++ concentration. Total K + was also found below 6.6 mg/L. Na concentrations were ranging from 6.5 to 8.7 mg/ L. Generally, the results from this study show no significant difference between waters from forest and deforested area in terms of chemical analysis but clear contrast in physical properties. The nutrient concentration of water fro m the forested site is relatively higher and untypical in the case of n itrate concentratio ns than deforested and agricultural water samples.