نوع مقاله : مقاله پژوهشی
استادیار دانشگاه پیام نور، ایران.
عنوان مقاله [English]
The morphometric characteristics show the morphology of the basins and reflect the geological conditions and geomorphological processes over time (Hurters et al., 1999).Different morphometric characteristics depend on various aspects such as geology, geomorphology, vegetation, climate, etc. (Rapot et al., 2015).The morphometric characteristics of the basin are important in hydrological research such as groundwater potential assessment, groundwater management, basin management, and environmental assessment (Raymond et al., 2017).In recent decades, due to the advancement of computer technology, morphometric studies of the basin are very convenient for the past.The use of GIS and the use of DEM is a precise, quick and inexpensive method for analyzing hydrologic systems (Schmidt and Sandwall, 2004).The Kamyaran basin has a different lithological diversity and different tectonic conditions in different areas of the basin.The geomorphologic conditions of the basin in the southern heights are mainly karstic and in the northern regions of irregular slopes with low permeability.Therefore, the purpose of this research is to identify morphometric effects on groundwater resources of Kamyaran basin.
- materials and methods
In this study, first, using a 10 meter DEM of the basin and utilizing the Arc Hydro tool, the limits of Kamyaran basin and drainage network of the basin were plotted.The Australian method was used to rank the watercourses and use topographic maps of 1: 25000 of the area for the accuracy of the watershed network.Seven parameters of linear morphometry, seven morphometric parameters and three morphometric parameters for rippling were calculated for Kamyaran basin.Based on the results obtained from morphometric parameters and geological and geomorphological conditions analysis and their adaptation to the distribution pattern of spring springs and their average annual discharge rate, the effects of morphometric characteristics on groundwater resources are determined.DEM 10 meters, topographic maps 1: 25000, geological map of 1: 100000, and Dubai springs sources are the data used in this study.
The drainage pattern of the Kamyaran basin is dendritic or tree type, and the drainage of the basin is rated 7.The total number of streams in the Kamyaran Basin is 29,776 and the first ones constitute 78% of the total catchment of the basin, indicating a low permeability of the basin.The split ratio of Kamyaran basin is 4.5 and indicates the lithological diversity of the basin.The total length of Kamyaran basins is 2446 km. Routes 1 make up about 61% of the total length of the basin drainage.Abrasives ranked 1 make up about 61% of the total length of the basin drainage. This is due to low-lying reservoir permeability.Also, the difference in mean length of the waterways was due to topographic conditions and slope of the watershed, since the values of the ratio of the length of different river runs to different ranks of the order did not show, The Kamyaran Basin is erosion in the younger stages of the erosion cycle.The drainage rate of the Kamyaran basin is 2.61 Km / Km2, which indicates the low permeability of the basin.Drainage density in the karstic areas in the south of the basin is 1.15, indicating a very suitable permeability of this area.The drainage flood in the Kamyaran basin 3.18, which confirms the high drainage density and low permeability in the basin.The rate of this parameter in the southwestern Karst regions of the basin is 1.02, which indicates high permeability and low drainage density.The drainage tissues of the Kamyaran Basin in the southwestern Karst regions of the basin are very coarse tissue and in other areas of very small type.The penetration number in the Kamyaran basin is 8.29 and 11.44, which indicates low penetration and high runoff coefficient.In the south karst area, the basin has a penetration number of 1.73, indicating high permeability and low runoff coefficient.The shape coefficients of the basin represent a relatively circular shape of the basin and high runoff coefficient.The roughness parameters also indicate significant difference in the height in the basin and as a result of rugged topography and relatively leaky and therefore low permeability.Groundwater potential of Kamyar basin is affected by morphometric conditions in the basin.The northern and central areas of the low power basin and the southern basins of the southwest basin have a high potential for underground water resources.
The most characteristic feature of the Kamyaran basin is the lithological diversity followed by different geomorphological conditions in different areas of the basin.The lithological diversity and variation of Kamyaran basin affect the values of linear morphometric parameters of the basin.In the impervious areas of the basin, the runoff coefficient is high and the penetration rate is lower and the conditions in the karstic areas are reversed.These differences are due to lithology conditions and heterogeneous geomorphology of the basin.Analysis of the values obtained from the three-dimensional morphometric, linear, shape and roughness parameters of the Kamyaran basin indicates that the lithologic conditions are very influential on morphometric parameters.The studied basin is also affected by lithological conditions in groundwater resources in the northern and central parts of the basin with low potential for underground water resources.The formation of karst geomorphology in the southern heights of the basin, by influencing the morphometric parameters and increasing the penetration rate, has created a high potential for groundwater resources and formed 5 karst springs in the south of the basin.