Ecology, Environment and Conservation Paper

MODELLING THE RELATIONSHIP BETWEEN LAND USE AND SURFACE WATER QUALITY

Mahdi Mahmoodi , Mahdi Honarmand , Farzin Naseri and Sedigheh Mohammadi

Abstract

This paper outlines a study aimed to assess the long-term association between land cover/land use change and water quality changes occurred in Razavi Khorasan Province of Iran. We used sensors of the TM, ETM + and OLI for the years 1987, 2001 and 2015 to investigate land cover changes. A series of significant land cover/land use change were identified within three time intervals, referring to satellite images based on RS and GIS standard techniques. A GIS was necessary to store, manipulate and analyse large volumes of land use data, and to carry out land use change analysis. To investigate the significance of trends in the time series of water quality variables, parametric trend tests were performed after removing variance. The water quality data available for the analysis in this study belong to the observed period from 1987 to 2015 in a river gauge station located at the outlet of the 36 catchments. Statistical analyses were employed to examine the statistical relationships of land use and water quality. The results from the statistical analyses revealed that there was a significant relationship between land use and in-stream water quality. Then, using multivariate linear regression model was trying to estimate water quality variables in the years 2029. Results demonstrated that with the exception of calcium (Ca) and potassium (K), the models estimate all other water quality variables with an acceptable degree of accuracy (P-value<0.05). The results identified the clear relationship between land use and the water quality indicators which can be used in environmental protection and land use planning. The findings of this study will be useful for policy makers, planners, and researchers to unveil the pollution, to adapt environmental and land use polices for sustainable development of river basin.