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چكيده انگليسي :

Effect of Landuse Chanege on Zayandehroud River Water Quality Fatemeh Bateni f bateni@in iut ac ir Date of Submission 2012 0 Department Natural Resources Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiSupervisor Sima Fakheran Alireza SoffianianAbstractLandscape characteristics and land use land cover patterns of a watershed are important factors that canaffect water quality of adjacent aquatic systems within a watershed Therefore quantifying landscapecomposition and con guration and its changes are essential for monitoring and assessment of ecologicalconsequences of human interference This study focuses on the effects of land use landscape patterns andlandscape dynamics changes in landscape patterns through time on the water quality of ZayandehroudRiver which is the most important river in center of Iran Dramatic population growth in addition toindustrial and agricultural development around the river over the past decades have resulted in the rapidlyincreasing water demand and pollutions which severely degrading Zayanderoud water quality Therefore monitoring Zayandehroud water quality is a critical issue especially noticing that freshwater is a scareresource in the central region of Iran The main goal of this study was to characterize the land use change inZayandehroud river basin in a period of eleven years 1997 2008 and to examine how landscape patterns including Number of Patches Edge Density Percentage of land use CONTAG Shannon and Simpson sDiversity Index influence on the water quality indices including BOD COD EC NO 3 P and TDS measured in 10 stations along the Zayandehroud river in Ghale shahrokh Tanzimi Dam Zamankhanbridge Kalle bridge Dizicheh lenj Mousiyan Choum bridge Ziyar bridge and Varzaneh Water qualitydata were retrieved from existing databases Land use and land cover maps of the area were prepared usinghybrid classification of multi temporal Landsat5 ETM images taken in September 1997 and 2008 Eightclasses of land use including Water Forest Cropland Rangeland Orchard Residential area Industrial areaand Bare land were identi ed Various metrics e g Simpson s Diversity Index ED CONTAG and PLANDwere calculated to quantify the landscape patterns changes and Pearson correlation test and regressionanalysis was applied to assess the relationship between landscape indices and water quality parameters Theincrease of built up land and bare land accounted for the most obvious transformation in the study area witha net gain of 106 ha and 1415 ha respectively This increase was traced to the conversion from rangeland which experienced the most drastic decrease by 1497 ha The results also indicated that water quality weresigni cantly correlated with both the proportions and con guration of Residential area Bare land andRangeland areas However there was no signi cant correlation between water quality variables andproportion of Forest in Zayandehroud basin Total edge of Industrial area had negative effects on waterquality especially on TDS and COD The proportion of rangeland was negatively correlated with waterquality variables Water quality was more likely to be degraded when there was high edge density of bareland It was shown that degradation of range land lead in to degradation of water quality which highlightsthe importance of rangeland conservation Results of this study can be used in establishing andimplementing effective water management at landscape scale in this region In addition the information onthe hydrologic effects of land use can provide guidelines not only for resource managers in restoring theaquatic ecosystem but also for policy makers in evaluating alternate land management decisions Keywords Land Use Land Cover Change Landscape Pattern Landscape Metrics Water Quality Pollution Watershed Zayandehroud River

باطني، فاطمه

اثر كاربري اراضي بر كيفيت آب رودخانه زاينده رود

پهنه بندي رودخانه , سيماي سرزمين