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Int.J.Curr.Microbiol.App.Sci (2018) 7(4): 853-866 International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 7 Number 04 (2018) Journal homepage: http://www.ijcmas.com Case Study https://doi.org/10.20546/ijcmas.2018.704.093 Morphometric Analysis of Patapur Micro-watershed in North-Eastern Dry Zone of Karnataka Using Geographical Information System: A Case Study B.D. Premanand1*, U. Satishkumar1, B. Maheshwara Babu1, S.K. Parasappa2, Mallikarjuna M. Dandu3, Ibrahim Kaleel4, N.L. Rajesh5 and S.A. Biradar6 1 Department of Soil and Water Conservation Engineering, College of Agricultural Engineering, UAS, Raichur, Karnataka, India 2 Department of Agricultural Engineering, College of Agriculture, UAS, Dharwad, Karnataka, India 3 Department of Agricultural Engineering, College of Agriculture, B’Gudi, UAS, Raichur, Karnataka, India 4 PFDC-WTC, PJTSAU, Rajendranagar, Hyderbad, India 5 Department of Soil Science and Agricultural Chemistry, College of Agriculture, UAS, Raichur, Karnataka, India 6 KVK, Vijayapaur, UAS, Dharwad, Karnataka, India *Corresponding author ABSTRACT Keywords Morphometry, Micro-watershed, QGIS techniques, DEM Article Info Accepted: 07 March 2018 Available Online: 10 April 2018 The application of remote sensing and geographical information system for the analysis of morphometric parameters are found to be of immense utility in watershed prioritization for soil, water conservation and natural resources management at micro level. Geomorphological analysis is the systematic description of watershed geometry and its stream system. These parameters directly or indirectly reflect the response of entire watershed based on causative factors that are affecting runoff and sediment loss. To prepare a watershed development plan, morphometric analysis have been studied in the Patapur micro-watershed (488.75 ha), being located at Raichur district of Karnataka. The boundary of the watershed was digitized from the SOI (Survey of India) toposheet and also DEM and slope maps were prepared with the help GIS techniques (QGIS). The morphometric parameters such as linear, aerial and relief aspects have been determined to understand the watershed characteristics. In the Patapur micro-watershed the bifurcation ratio (Rb) was varied from 1.75 to 4.0 with average of 2.88 which indicates that on undistorted geologic structure and drainage system of moderate peaks and lower order streams. The values of form factor (Rf), shape factor (Sb), circulatory ratio (Rc) and elongation ratios (Re) were 0.329, 2.28, 0.512 and0.647 respectively which indicates moderately elongated micro-watershed with leading moderate influence on time parameters. The estimated values of relief, relief ratio (Rr) and relative relief (RR) were found to be 114 m, 0.130 and 0.05 respectively, these indicates the possibly moderate erosion. Over all study suggests that the watershed should be treated with soil and water conservation measures. 853 Int.J.Curr.Microbiol.App.Sci (2018) 7(4): 853-866 Introduction Morphometry is the measurement and mathematical analysis of the configuration of the earth’s surface, including shape and dimension of its landforms, physical properties, interrelationship of morphological characteristics and hydrological behavior. The morphometric characteristics at given watershed scale contains important information regarding its formation and development due to all hydrologic and geomorphic processes occur within the watershed and it provides a quantitative description of the drainage system, which is an important aspect of the characteristics of watersheds. The morphological characteristics of a basin represent its attributes, which may be employed in synthesizing its hydrological response. Hydrologists and geomorphologists have recognized that certain relations are most important between runoff characteristics, and geographic and geomorphic characteristics of drainage basin systems. QGIS and remote sensing techniques have opened up wide range of avenues for effective watershed management, as they provide a flexible environment and a powerful tool for the manipulation and analysis of spatial information. The outcome of analysis of linear and areal parameters would be important in determining the effect of catchment characteristics and distribution of stream network of different orders within the catchment area. Materials and Methods The present study was carried out in the Patapur micro watershed (WS-Code: 4D3A4B1e) named after two villages (Patapur and Goladinni) found near the watershed, covers a total geographical area of 488.75 ha, which is part of the Tungabhadra sub basin and falls within the North-Eastern dry zone (Zone-2 of Region-1) of Karnataka and lies between 16˚ 07' 35.9'' N latitude and 760 51′ 33.3'' E longitudes to 16˚ 08′ 22.3'' N latitude and 76˚ 53′ 27.7'' E longitudes with an average elevation of 460 m above mean sea level (MSL) altitude in the Raichur district, Karnataka, India. This is located at about 65 km from the Raichur city on Raichur-Lingasugur state high way (SH No. 20) Figure 1. The hydrological delineated Patapur micro watershed considered for this study covered under the Survey of India toposheet of 56 D/16 (1:50,000). The elevation of the micro watershed ranges from 432 m to 546 m above mean sea level (MSL). The minimum elevation of 432 m found near the outlet where gauging station is existing and the maximum elevation 546 meters is over the hillocks at upstream side of the watershed. The geo-morphological characteristics of the micro-watershed were determined by digitizing the SoI toposheet using open source Quantum GIS (QGIS, version 2.6.1 Brighton) software and subsequent, cleaning editing and assigning topology produced a database in terms of linear, aerial and relief aspects of the watershed. The Patapur micro-watershed boundary was delineated using geospatial tools viz. QGIS and QSWAT. The morphological parameters directly or indirectly reflect the entire watershed behaviour on causative factors affecting runoff and sediment loss. The parameters namely size, shape, slope, relief, stream density and stream network system were worked out from the drainage map derived from DEM using the capabilities of open source QGIS software and Google earth images. The drainage map of the study area was used for quantitative analysis of the drainage basin. 854 Int.J.Curr.Microbiol.App.Sci (2018) 7(4): 853-866 Linear aspects of channel systems B= The linear aspects of morphometric analysis of basin include stream order, stream length, mean stream length, stream length ratio and bifurcation ratio. There are different systems of ordering streams that are available. Strahler’s system, which is a slightly modified of Hortons system, has been followed because of its simplicity, where the smallest, unbranched fingertip streams are designated as 1st order, the confluence of two 1st order channels give a channels segments of 2nd order, two 2nd order streams join to form a segment of 3rd order and so on. When two channel of different order join then the higher order is maintained. The trunk stream is the stream segment of highest order. It is found that Patapur micro-watershed tributaries are of 3rd order. In all 12 streams were identified of which 7 are first order, 4 are second order, and 1 is 3rd order. Drainage patterns of stream network from the micro-watershed have been observed as mainly of dendritic type which indicates the homogeneity in texture and lack of structural control. The properties of the stream networks are very important to study basin characteristics (Strahler, 2002). Basin length (Lb) It is the maximum length of the basin measured from the outlet to the remotest point. It was measured using the following equation; L b = 1.312 × A 0.568 A L b (2) Where, A = Area of the basin, km2 Lb = Basin length, km Bifurcation ratio (Rb) It is related to the branching pattern of the drainage network. It was determined by using the following equation; Rb= Nu N u +1 (3) Where, Nu = Number of streams of the given order Nu+1 = Number of streams of the next higher order Mean stream length ( L u ) Length of stream is indicative of the contributing area of the basin of that order. The stream length is used to determine the basin perimeter, basin length and drainage density. It was calculated by using the following equation; (1) Where, N L u Lb = Basin length, km A = Area of the basin, km2 Lu  Average basin width (B) Where, It is the width of the watershed and was determined by using the following equation; Nu = Number of streams of the given order Lu = Length of stream having order u, m 855 i 1 Nu (4) Int.J.Curr.Microbiol.App.Sci (2018) 7(4): 853-866 Stream length ratio (RL) Lengths of each stream segment of each order were measured for the watershed. The total and mean lengths and the length ratios were calculated for the watershed using the following expression; Stream frequency (F) It is defined as number of stream segments per unit area and was calculated by using the following equation; Lu L u-1 (5) RL = Dd= Drainage density, km. km-2 Lu = Length of stream order, km Nu = Number of streams A = Area of watershed, km2 u N F=∑ u i =1 A (7) Where, Lu = The total stream length of the order ‘u’ Where, L u-1 = The total stream length of its next lower order. Nu = Total number of streams of all orders Areal aspects of drainage area A = Area of the basin, km2 The aerial aspects play a very important role in the watershed development and these are very essential characteristics of the watershed. Form factor (Rf) The aerial parameters such as drainage area, drainage density, stream frequency, form factor, circulatory ratio, circulatory index, elongation ratio, compactness co-efficient, ellipticity index and texture ratio were determined using drainage map in QGIS environment. The detailed calculation of these parameters is explained hereunder. Drainage density (Dd) Drainage density is derived as the ratio of total stream segment length cumulated for all orders to the drainage area (A) and calculated using the following equation; u Dd  L i 1 u  Nu A It was measured as the dimensionless ratio of drainage area (A) to square of the length by using the following expression; A L2b (8) Rf = Where, A = Area of watershed, km2 L= length of the basin, km Circulatory ratio (Cr) It was measured as dimensionless ratio of basin area (A) to the area of a circle (Ac) whose circumference is the same as that of the basin perimeter (Pb) by using the following expression; (6) Cr  Where, 856 4 Pb2 (9) Int.J.Curr.Microbiol.App.Sci (2018) 7(4): 853-866 Where, Ellipticity index (Ei) P = Perimeter, km The value of circulatory ratio varies from zero (in a line) to one (in a circle). The value of ellipticity index varies from 1.0 to infinity and it is inversely proportional to the form factor. Ellipticity index was calculated using the following formula; Higher the values of circulatory ratio, more circular will be the shape of the basin and vice-versa. πL Ei = 4A (12) Elongation ratio (Er) Where, Elongation ratio is the ratio of the diameter of a circle which has same area as the basin to the maximum length of the basin, which was calculated by using the following equation; A = Area of watershed, km2 L = Length of watershed, km Er = 2 Texture ratio (Rt) It is the number of first order streams per unit perimeter of length of the drainage basin. 2R'e Lb (10) Where, It was calculated by using the following formula; Re = Radius of circle equivalent to area of the watershed, km Rt = Lb = Length of the basin, km Re is given by A = π (Re) watershed 2 N1 P (13) Where, and A is area of Compactness coefficient (Cc) N1 = Number of first order streams P = Basin perimeter, km Relief aspects of stream network It was measured as the ratio of the perimeter of watershed (Pb) to the circumference (P΄b) of a circle equivalent to the area of the watershed, which is expressed below, The relief aspects are important terrain parameters from utilization point of view and also in assessing disaster prone areas. Where, The slope is very important for assessing land capability, erodibility and stability. In order to derive the relief aspects, the contours developed from DEM for the Patapur watershed were used. A = Area of watershed, km2 Pb = Perimeter of the basin, km The detailed calculation of relief aspects of stream network is explained hereunder. Cc  Pb Pb' (11) 857 Int.J.Curr.Microbiol.App.Sci (2018) 7(4): 853-866 Stream slope (S) The stream slope has profound effect on the velocity of flow and in turn on the discharge from the drainage area. The slope of the drainage area was computed as the fall from the head of the first order channel to the gauging station divided by the main stream length (Lc). Rr = Relief ratio Lb = Basin length, km H = Maximum watershed relief, m Ruggedness number (RN) The product of relief (H) and drainage density (Dd) is called as ruggedness number. It was calculated by the following expression; R N  H  D d (16) Maximum watershed relief (H) Maximum watershed relief (H) is the elevation difference between basin mouth (discharge point) and the highest point on the basin perimeter. Maximum watershed relief for the present study was determined from the contour lines. Where, Relative relief (RR) The geometric number is a ratio of Ruggedness number to the slope of the ground surface. It was calculated by the following expression; It is the product of maximum watershed relief to the length of perimeter. It was computed by using the following formula; Dd = Drainage density, km.km-2 H= Watershed relief, m Geometric number Geometric number = RR = H Lp (14) Sg = Slope of ground surface, km. km-1 H = Maximum watershed relief, m RR = Relative relief, % H = Maximum watershed relief, m Lp = Length of perimeter, m Time of concentration (Tc) Relief ratio (Rr) It is ratio of maximum watershed relief divided by the maximum watershed length. It was computed by using following expression; Where, (17) Where, Where, H Rr = L b (15) H X Dd Sg The time required for runoff water to move from the most remotest point of the watershed to its outlet is called as time of concentration (Tc). It was obtained from the following expression; Tc = 3.97 L0.77S-0.385 (18) Where, Tc = Time of concentration, min 858 Int.J.Curr.Microbiol.App.Sci (2018) 7(4): 853-866 L = Length of watershed from remotest point to outlet, km S = Slope of the catchment, mm-1 Basin relief (S) The basin relief is measured as the ratio of elevation difference between highest elevation (HE) point in the basin and lowest elevation (LE) at gauging station divided by main valley length. It was calculated by using following equation; perimeter of 10950.12 m and basin length of 3855.25 m. The micro-watershed has total 12 streams with highest stream of 3rd order and drainage pattern resembles to dendrite. The length of 1st order, 2nd order and 3rd order were 3853.2, 2908.7and 488.10 respectively. It observed from the Table 1 that, mean stream length varied from 488.10 to 727.17 m. L = Length of basin, m HE = Highest elevation, m LE = Lowest elevation, m However, in general, the mean length of the stream of the particular order increases with the increase in the order of stream which means the mean length of a stream of a given order is greater than that of immediate lower order. But, in the present case, mean stream length of the third order is lesser than its immediate lower order which might be due to variations in slope and topography. The other important property i.e. bifurcation ratio (Rb), it is observed from the Table 1, the Rb is not same from one order to its next order and it varied from 1.75 to 4.00 with average Rb of 2.88. The terrain analysis tool of QGIS was used to derive the Digital Elevation Model (Fig. 2), slope map (Fig. 3) contour map (Fig. 4) and relief map (Fig. 5) from SRTM. The derived slope map for the micro watershed was reclassified using re-class tool of QGIS to slope ranging between 1 to 68.5 per cent. The stream length ratio of the microwatershed ranged between 0.75 and 0.17. The ratio depicts that lower reaches of the watershed had smaller channels (order 3) than the upper reaches (order 1 and 2). This may be because of the steeper slope in the upper reaches than in lower reaches. Results and Discussion Relation between stream number and stream order  Basin relief HE  LE  100 L (19) Where, The geomorphological analysis and measurements were made from the digitized drainage pattern map of the Patapur microwatershed. Watershed boundary and digitized drainage pattern are shown in Figure 6. Linear aspects of drainage network The stream order, stream number, bifurcation ratio and stream length ratio were analyzed for the micro-watershed. The micro-watershed comprises an area of 488.75 ha with a The relationship between stream order and logarithm of stream number was plotted and is shown in the Figure 7. The graph clearly depicts there is one to one straight line relationship between the stream number and stream order which is satisfying the Horton’s law of stream order. It is evident that the correlation coefficient and coefficient of determination for the straight line fit for the watershed were 0.97 and 0.94, respectively which are quite satisfactory. 859 Int.J.Curr.Microbiol.App.Sci (2018) 7(4): 853-866 Table.1 Morphological characteristics of study area Sl. No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 Morphological characteristics Estimated values Linear Aspects Parameters Area, ha Perimeter, m Basin length(Lb),m Stream order I II III Stream length(Lu), m I II III Mean stream length, m I II III Bifurcation ratio (Rb) R1 R2 Mean The areal aspects parameters Stream length ratio (Lu) R1 R2 Mean Drainage density (Dd), km km-2 Stream frequency (F), no.ha-1 Drainage Texture (Dt), no.km-1 Farm factor (Rf) Circularity ratio (Rc) Elongation ratio(Re) Length of overland flow(Lg), km km2 Compactness coefficient (Cc) Circulatory index(Ic) Avg. basin width, m Shape factor (Sb) The relief aspects parameters Texture ratio (Rt) Ruggedness no. (RN) Geometric No. Relief ratio (Rr), km2 Relative relief (RR) Total relief (H) Constant of channel maintenance (C) Time of concentration (Tc) 860 488.80 10950.12 3855.250 7 4 1 3853.20 2908.70 488.10 550.00 727.17 488.10 1.75 4.00 2.88 0.75 0.17 0.46 1.48 0.025 1.096 0.329 0.512 0.647 1.350 1.398 0.512 1267.88 2.28 0.639 0.744 0.0029 0.130 0.050 114.00 0.46 36.64 Int.J.Curr.Microbiol.App.Sci (2018) 7(4): 853-866 Fig.1 Location map of Patapur microwatershed in the Raichur district of Karanataka Fig.2 DEM map of Patapur micro-watershed 861 Int.J.Curr.Microbiol.App.Sci (2018) 7(4): 853-866 Fig.3 Slope map of Patapur micro-watershed Fig.4 Contour map of Patapur micro-watershed 862