MORPHOMETRIC ANALYSIS OF KHULGAD WATERSHED ALMORA, UTTARAKHAND

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1 MORPHOMETRIC ANALYSIS OF KHULGAD WATERSHED ALMORA, UTTARAKHAND Zainab Fatima 1 1 Interdisciplinary Dept. of Remote Sensing and GIs Application Aligarh Muslim University Aligarh Abstract-Rivers are the dynamic and increasingly important part of the physical environment Rivers usually has well-defined spatial boundaries and these are the medium of energy exchange from one place to another place in external environment. Morphometry is the measurement and mathematical analysis of earth s surface, features, forms and the dimension of the landforms. Morphometric analysis requires measurement of linear features, aerial aspects and gradient of channel network of the drainage basin. Morphometric parameters are relevant and useful to identify various hydraulic characteristics of drainage basin i.e. patterns, shape, stage of stream, permeability of bed rock, health of streams, as well as help to correlate with lithological characteristics. The study area, is the Khulgad Watershed ( N lat. and E long.) lies 15 km north-west of Almora township in the Khulgad watershed of Kosi River. The GIS based Morphometric analysis of this drainage basin revealed that the Khulgad watershed is 6th order drainage basin and drainage pattern mainly is dendritic type thereby indicates homogeneity in texture and lack of structural control and The dendritic pattern of drainage indicates that the soil is semi pervious in nature. Total number of streams is 929, in which 711 are first order, 173 are second order, 33 are third order and 9 are fourth order streams 2 are fifth order streams and 1 is sixth order stream. The length of stream segment is maximum for first order stream and decreases as the stream order increases. The drainage density (Dd) of study area is 0.80 and mean bifurcation ratio is This study would help the local people to utilize the resources for sustainable development of the basin area. I. INTRODUCTION Morphometric analysis of a watershed provides a quantitative description of the drainage system, which is an important aspect of the characterization of watersheds (Strahler, 1964). Morphometric descriptors represent relatively simple approaches to describe basin processes and to compare basin characteristics (Mesa 2006) and enable an enhanced understanding of the geomorphic history of a drainage basin (Strahler 1964). Drainage basin morphometric parameters can be used to describe the basin characteristics. These are basin size (stream order, stream length, stream number, and basin area), bifurcation ratios, drainage density. The risk factor of flood is indirectly related with the bifurcation ratio (Waugh 1996). Quantitative expression of drainage basin shape or outline form was made by Horton (1932) through a form factor. 1.1 Statement of the problem The study of rivers and their works has an important place in geomorphology, especially in fluvial geomorphology. The river channels play a key role in the development of fluvial landforms. These parameters have been used in various studies of fluvial geomorphology and surface-water hydrology, such as flood characteristics, sediment yield, and evolution of basin morphology, risk assessment and vulnerability etc. DOI: /IJMTER GPMKR 162

2 II. REVIEW OF LITERATURE In order to model the hydrological processes in a multi-vegetated watershed it is necessary to update the information regarding the response of these processes to various watershed parameters. This quantitative Morphometric analysis of watersheds was continued by a series of methodological and theoretical papers spanning more than a quarter century (Langbein 1947; Schumm 1956). Jamieson et al (2004) showed that tectonic zones in the Indus Valley of Ladakh, in north India, can be differentiated using morphometric analyses of longitudinal valleys. Morphometric analysis through remote sensing and GIS techniques have been attempted by a number of researchers (Nautiyal, 1994; Srivastava, 1997; Nag, 1998; Agarwal, 1998; Biswas, et al., 1999; Singh et al., 1997; Vittala et al 2004; Reddy et al., 2004) and all have arrived to the conclusion that remote sensing and GIS are the powerful tools for studying basin morphometry and continuous monitoring. Ajoy Das et al (2012) have used remote Sensing and GIS techniques for generation of various thematic maps such as geomorphology, drainage, watershed and surface water, landuse/land cover, soil and slope. These maps were used for prioritization of mini watersheds through morphometric analysis. Nageswara Rao (2010) carried out morphometric analysis of the Gostani River Basin in Andhra Pradesh using Spatial Information Technology (SIT) in the delineation of drainage pattern and for water resources management and planning. The basin morphometric parameters such as linear and aerial aspects of the river basin were determined and computed. The area is occupied by 96% khondalite group (quartz, feldspar, garnet sillimanite gneiss) of rocks. It is a 7th order drainage basin and observed that the drainage density is low which indicates the basin is highly permeable subsoil and thick vegetative cover. The circularity ratio value reveals that the basin is strongly elongated and highly permeable homogenous geologic materials. This study would help the local people to utilize the resources for sustainable development of the basin area. Markose and Jayappa (2012) have investigated the influence of tectonic activity in Kali river basin, southwest coast of India through an analysis of the geomorphic indices computed through GIS. There are five geomorphic indices such as stream length gradient index, asymmetry factor, hypsometric integral, valley floor width-to-height ratio, and elongation ratio were utilized for identification of evidences of tectonic activity. The results obtained from these indices were combined to develop an index of relative tectonic activity classes. The relative tectonic activity shows low and medium values, which indicate the highest degree of tectonic activity compared to the upland plateau regions. III. OBJECTIVES The present study on morphometric analysis of Khulgad Watershed using ASTER data and GIS techniques aims to, 1. Identify drainage bifurcation system and their nature. 2. Understand the Morphometric Parameters behavior of the area. 3. Prioritize the watershed through morphometric parameters and present land use 4. Study Area IV. GEOGRAPHICAL AREA The study area, viz. the Khulgad Watershed ( N lat. and E long.) lies 15 km north-west of Almora township in the Khulgad watershed of Kosi River. Khulgad watershed encompassing an area of 32 km^2 within altitude 1150 m and 2190 m, having cool temperate climate with an annual average temperature of 20C and an annual average rainfall of 935 mm. Geomorphological, the landform are mature, valleys are fluvially eroded and are unusually wide, with terraces and alluvial fans (Rai,1993). On the basis of land use, All rights Reserved 163

3 watershed is divisible into 8 areas (rawat, 1992). About 26% area of the watershed is under poorly managed agriculture, 31% under unrestricted grazing, 4% under horticulture, and nearly 39% is covered by forest of oak and pine Almora is situated on a horseshoe ridge of mountain, the eastern portion of which is called talifat and the western one is called as selifat. Kosi River flows through Almora district. It is famous for its beauty and views of Himalayas, cultural heritage. Map 1: Location Map of Khulgad Watershed V. DATA SOURCE AND METHODOLOGY The present study integrated the use of remote sensing and GIS techniques in morphometric analysis, and the results of morphometric parameters determined are briefly described and discussed. The study of basin morphometry attempts to relate basin and stream network geometries to the transmission of water and sediment through the basin. The size of a drainage basin acts upon the All rights Reserved 164

4 of water yield, the length, shape and relief, affect the rate at which water is discharged from the basin. The morphometric analysis is carried out with respect to the parameters like stream order, stream length, bifurcation ratio, stream length ratio, basin length, drainage density, stream frequency, elongation ratio, circularity ratio, form factor, and relief ratio using mathematical formulae. Morphometric analysis of the watershed Morphometry is the measurement and mathematical analysis of the configuration of the earth's surface, shape and dimension of its landforms (Agarwal, 1998; Obi Reddy et al., 2002). A major emphasis in geomorphology over the past several decades has been on the development of quantitative physiographic methods to describe the evolution and behavior of surface drainage networks (Horton, 1945; Leopold & Maddock, 1953; Abrahams, 1984). Different morphometric techniques, like absolute relief, relative relief, dissection index, average slope, drainage density and ruggedness index are considered for quantitative analysis of different attribute of the watershed. A point layer is generated in the ArcGIS s/w environment and the spot heights are collected according to the longitudinal and latitudinal value. Then spot height attribute for each sample location is introduced to the point layer. All point data are interpolated to the raster through krigging interpolation (Matheron, 1970) techniques in the ArcGIS s/w environment. Both interpolated and surfacing outputs are merged to create raster digital elevation model (DEM) for the Khulgad watershed. 5.1 Methodology A systematic approach involving multiple steps is necessary for the spectacular working style. In the present study, it begins with review of literature and collection of information/ data about the study area. Afterwards, the various steps taken under consideration while preparing the useful datasets for the present study are as follows, shown in mentioned flow chart. However, in terms of pre-processing, other useful steps such as geo-referencing, rectification, geometric corrections to retain spatial distortions within the dataset are also taken under consideration 5.2 Generation of Digital Elevation Model (DEM) The digital elevation data for the study area was downloaded from ( The ASTER GDEM is 1x1 tiles in GEOTIFF format with lat-long coordinates and a 1 arc-second (30 m) grid of elevation posting and referenced to the WGS84 datum and vertically referenced to WGS84 EGM 96 Geoid. The horizontal and vertical accuracy has been reported to be less than 30 and 20 meters respectively with 95% accuracy. Filling sinks: When delineating stream networks form DEMs, it is necessary to fill sinks. A sink is a cell or set of spatially connected cells whose flow direction cannot be assigned to one of the eight valid values in a flow direction grid. This can occur when all neighboring cells are higher than the processing cell, or when two cells flow in to each other creating a two-cell loop(esri2009). Sinks in the DEM were filled up with the FILL function. It is an iterative process that goes to each cell and fills the sinks by comparing the value of neighboring cells until all the sinks are filled. Even though creating a depression less DEM was the goal, sinks were minimized to 0.1 million cells from 3.6 million. Generation of flow direction: The direction of flow was determined by finding the direction of steepest descent from each cell. This was calculated as: maximize drop = (change in z-value)/ (distance)ˆ100. The distance is determined between cell centers. Therefore, if the cell size is 1, the distance between two orthogonal cells is 1 and the distance between two diagonal cells is If the descent to all adjacent cells is the same, the neighborhood is enlarged until a steepest descent is found (ESRI 2009). The function FLOWDIRECTION was used to calculate the direction of flow of each cell. Generation of flow accumulation: Flow accumulation represents the accumulated flow in each grid cell. It was calculated by using flow direction and by counting the number of cells flowing to a particular cell. Thus, flow accumulation represents the number of upstream cells of any cell in an area. All rights Reserved 165

5 FLOWACCUMULATION function was used to calculate this automatically while it takes the flow direction grid as input. Generation of stream network: A set of thresholds of 10, 100 and 1000 pixels were used to generate stream network. All the cells in the flow accumulation grid that were above or equal to those threshold values were identified to generate raster linear networks. The output grids were then vectorized using the STREAMLINE function of ArcGIS, which takes raster linear networks and flow direction raster as input to produce linear vectors that also show the direction of flow (Figure 3). Once the streams were accurately derived, the watersheds (sub-basins) were delineated using available pour point. Generation of watersheds: Pour point was generated to derive the sixth order stream network for the entire study area. Strahler s stream ordering method was used to categorize streams in to different orders based on the location of stream from stream head to tail of the watershed VI. RESULT AND DISCUSSION Morphometric analysis, which is all about exploring the mathematical relationships between various stream attributes, used to compare streams and to identify factors that may be causing differences. The term Morphometric is derived from a Greek word, where morph means earth and metry means measurement, so together it is measurement of earth features. This is an important factor for planning any watershed development. Morphometric analysis also provides description of physical characteristics of the watershed which are useful for environmental studies, such as in the areas of land use. Map 2: Digital Elevation All rights Reserved 166

6 Quantitative assessment of these drainage parameters has been carried out using standard mathematical formulae given by Chopra et.al (2005), which are tabulated in Table 1 Morphometric Formula Reference Parameters Stream order (u) Hierarchail rank Strahler(1964) Stream length (Lu) Length of streams Horton (1945) Mean stream length (Lsm) Stream length ratio (RL) Bifurcation ratio (Rb) Drainage density (D) Lsm = Lu/Nu Where, Lsm = Mean stream length Lu = Total stream length of order u Nu = Total no. of streams segments of order u RL = Lu/Lu1 Where, RL = Stream length ratio Lu = Total stream length of order u Lu1 = Total stream length of its next lower order Rb = Nu/Nu1 Where, Rb = Bifurcation ratio Nu = Total no. of stream segments of order u Nu1= No. of segments of the next higher order D = Lu/A Where, D = Drainage density Lu = Total stream length of all orders A = Area of the basin (Km 2 ) Strahler(1964) Horton (1945) Schumn (1956) Horton All rights Reserved 167

7 DEM is an important step in delineating any morphometric parameters. The first step in any hydrologic Modelling is to fill the elevation grid. Map 3: Fill All rights Reserved 168

8 Morphometric analysis for the present study is grouped into three classes such as linear aspects, areal aspects and relief aspects Stream Order (Su) The order of the stream is based on the connection of tributaries. Stream order is used to represent the hierarchical link among stream segments and allows drainage basins to be classified according to size. Stream order is a fundamental property of stream networks as it relates to the relative discharge of a channel segment. A number of stream-ordering systems in the present study have been used which was formulated by Arthur N. Strahler. According to the analysis, first order streams are having no stream tributaries and that flows from the stream source. A second-order segment is created by joining two first-order segments, a third-order segment by joining two second order segments, and so on. There is no increase in order when a segment of one order is connected by some other lower order. Strahler stream order has been applied by many researchers for river systems. The highest stream order observed in the present study area is sixth order out of 929 observed streams. 711 first order, 173 second order, 33 third order 9 fourth order 2 fifth order and 1 sixth order streams were observed. Dendritic drainage pattern formed by the interlinking of streams is observed in the study area which indicates the homogeneity in texture and lack of structural control. Dendritic drainage has a spreading, tree-like pattern with an irregular branching of tributaries in many directions and with any angle. It is observed that the maximum frequency is in case of first order streams. It is noticed that there is a decrease in stream frequency as the stream order increase. Table: 2 Stream Ordering Stream order No of streams 1 st nd rd 33 4 th 9 5 th 2 6 th Stream Number (Nu) The count of stream channel in given order is termed as stream number. Horton s law states that the number of streams of different orders in a given basin tends closely to approximate as inverse geometric series of which the first term is unity and the ratio is the bifurcation ratio. The stream frequency is inversely proportional to stream order and stream number is directly proportional to size of contributing basin and to the channel dimension. Higher the stream number indicates lesser permeability and infiltration. It leads to inference that several stream usually upsurges in geometric progression as stream order increases. The variations in rock structure in the basin are responsible for disparity in steam frequencies of each All rights Reserved 169

9 Map 4: Stream order 6.3 Stream Length (Lu) Stream length is the total length of stream segment of each of the consecutive order in the basin tends approximate a direct geometric series in which the first term is the average length of the first order. It s the quantification of hydrological characteristics of bedrock and the drainage extent. When bedrock is of permeable character then only subtle number of relatively longer streams is formed in a well-drained basin area. On the other hand, when the bed rock is less permeable then large number of smaller length of streams in the basin are produced. Stream Order Stream Length 1 st nd rd th th th All rights Reserved 170

10 Table 3: Stream Length 6.4 Bifurcation Ratio (Rb) Bifurcation Ratio (Rb) is defined as the ratio of the number of streams of any order to the number of streams of the next highest order (Strahler 1957). Values of Rb typically range from the theoretical minimum of 2 to around 6. Typically, the values range from 3 to 5. The bifurcation ratio is calculated as Rb = Higher Order + 1/Next Lower Order Horton (1945) considered bifurcation ratio as an index of relief and dissection. According to Strahler (1957), bifurcation ratio exhibit subtle fluctuation for different region with varied environment except where powerful geological control dominates. According to Schumm (1956), bifurcation ratio is the ratio of number of stream segment of given order to the number of segment in the next order, it is dimensionless property and indicates the degree of integration prevailing between streams of various orders in drainage basin. Strahler significantly marked that geological structures do not affect drainage pattern for bifurcation ratio is in between 3.0 to 5.0. When bifurcation ratio is low, there will be high possibilities of flooding as water will tend to accumulate rather than spreading out. The human intervention plays important role to reduce bifurcation ratio which in turn augment the risk of flooding within the basin, this was noted significantly by. Stream Order 1 st nd rd th th 2 6 th Bifurcation Ratio Table: 7 Bifurcation ratio The mean value of bifurcation value is Drainage pattern of Khulgad watershed The drainage pattern for the present study area is dendritic. The drainage pattern shows well integrated pattern formed by a main stream with its tributaries branching and rebranching freely in all direction. The dendritic pattern of drainage indicates that the soil is semi pervious in nature. 6.6 Drainage Density (D) The drainage density (Horton 1932), D is the ratio of the total length of streams within a watershed to the total area of the watershed; thus D has units of the reciprocal of length (1/L). A high value of the drainage density would indicate a relatively high density of streams and thus a rapid storm response. Table: 11 Drainage density Drainage density 0.80 Map 5: Drainage All rights Reserved 171

11 Summary Table S.no Stream order Stream number Stream length Mean stream length Stream length ratio Bifurcation ratio 1 1 st nd rd th th th Total Max basin length Basin perimeter Basin area Drainage density (D) 0.80 VII. CONCLUSION Watershed is a basic unit for morphometric analysis. Remote sensing and GIS techniques are known for providing very high accuracy in mapping and measurement done in morphometric analysis. Stream ordering, stream length, stream order, bifurcation ratio, flow direction flow accumulation, drainage density are the most useful criteria for the morphometric classification of a watershed. Prominently drainage basin morphometry is significant approach that reflects existing geomorphic process operating in fabric of a drainage basin. Drainage basin morphometry explicitly reveals quantitative information on landform. In simple words, the quantitative evaluation of morphometric parameters is essential tool in river basin analysis in terms of soil and water conservation and natural resource management In regards to formation and development i.e. evolution of land surface process depends on morphometric nature of basin. The morphometric assessment of drainage system is imperative to any hydrological studies. Also, co-relation of stream network behavior plays significant role. Therefore, various hydrological phenomena of drainage basin can be in relevance to size, shape of drainage basin. Meticulous study of morphometry of all sub-basins reveals drainage pattern which further infers to lithological nature. One can co-relate the morphometric nature of basin with the sediment- yield coming from the basin, similarly, the aspect of morphometry can be linked with the flow characteristics, sediment transports and fluvial process. The study reveals that remotely sensed data (ASTER-DEM) and GIS based approach in evaluation of drainage morphometric parameters and their influence on landforms, soils and eroded land characteristics at river basin level is more appropriate than the conventional methods. GIS based approach facilitates analysis of different morphometric parameters and to explore the relationship between the drainage morphometry and properties of landforms, soils and eroded lands. Different landforms were identified in the watershed based on ASTER (DEM) data with 30 m spatial resolution, and GIS software. GIS techniques characterized by very high accuracy of mapping and measurement prove to be a competent tool in morphometric analysis. The morphometric analyses were carried out through measurement of linear, areal and relief aspects of the watershed with more than 85 morphometric parameters. The morphometric analysis of the drainage network of the watershed show dendritic and radial patterns with moderate drainage texture. The variation in stream length ratio All rights Reserved 172

12 be due to change in slope and topography. The bifurcation ratio in the watershed indicates normal watershed category and the presence of moderate drainage density suggesting that it has moderate permeable sub-soil, and coarse drainage texture. The value of stream frequency indicate that the watershed show positive correlation with increasing stream population with Application of Remote Sensing and GIS technique in morphometric analysis for efficient planning and management of drainage basin. The present study conducted in Khulgad watershed district Almora Uttarakhand region advocates that remotely sensed data and GIS based approach in evaluation of drainage morphometric parameters and analysis of land use and land cover, is more appropriate than the conventional methods. GIS techniques characterized by very high accuracy of mapping and measurement prove to be a competent tool in morphometric analysis of the study area covers, remotely sensing technology reveals a very significant role, by multi-temporal interpretation of satellite data. The digital elevation model (DEM) and slope map of the catchment area has been generated from ASTER data of 30 m resolution shows that the elevation in the study area ranges between 241 to 2727 m. The morphometric analyses were carried out through measurement of linear, areal and relief aspects of the catchment area using standard morphometric parameters. The morphometric analysis of the drainage network of the catchment area exhibits sub-dendritic drainage patterns with moderate drainage texture. The variation in stream length ratio might be due to difference in slope and topographic conditions. The variation of bifurcation ratio in the catchment area is ascribed to the difference in topography and geometric development. This variation in the value of bifurcation ratio reveals less structural control on the drainage development. The presence of high drainage density suggests that the catchment area has impermeable subsurface materials and mountainous relief. The stream frequency in the catchment area exhibit positive correlation with the drainage density, indicating the increase in stream population with respect to increase in drainage density. REFERENCES [1] Abrahams, A. D. (1984). Channel networks: a geomorphological perspective. Water Resour Res., [2] Agarwal CS (1998) Study of drainage pattern through aerial data in Naugarh area of Varanasi district U.P. Journal of the Indian Society of Remote Sensing 26: [3] Agarwal, C. S. (1998) Study of drainage pattern through aerial data in Naugarh area of Varanasi district, U.P., Jour. Indian Soc. Remote Sensing [4] Al Saud M Morphometric analysis of wadi aurnah drainage system, western arabian peninsula. [5] Alexander, P.O (1979), "Age and Duration of Deccan Volcanism: K. Ar. Evidence", Deccan Volcanism Geological Society of India, Memoir No. 3, Bangalore, pp [6] Babar M Hydrogeomorphology: fundamentals, applications and techniques. New Delhi: New India Publishing [7] Bali R, Agarwal K, Nawaz Ali SN, Rastogi S, Krishna K Drainage morphometry of himalayan glacio-fluvial basin, india: hydrologic and neotectonic implications. Environ Earth Sci. 66: [8] Bates, N. (1981). Practical foundations of physical geography, Valley shapes. In B. Knap (Ed.), London: George Allen & Unwin, [9] Broscoe, A.J (1959), Quantitative Analysis of Longitudinal Stream Profiles of Small Watersheds, Project N , Tech. Bep. 18, Geology Department, Columbian University, ONR, Geography Branch, New York. [10] Calef, W. C (1950), Form and Process, Cambridge University Press, London, pp 473. [11] Chopra R, Dhiman RD, Sharma P Morphometric analysis of sub-watersheds in gurdaspur district, Punjab using remote sensing and GIS techniques. J Indian Soc Remote Sens. 33: [12] Chorley, R.J (1972), Spatial Analysis in Geomorphology, Mathuen and Co. Ltd., London. [13] Chorley, R.L (1967), Models in Geomorphology, in R.J. Chorley and P. Haggett (eds.), Models in Geography, London, pp [14] Dury, G.H (1952), Methods of Cartographical Analysis in Geomorphological Research, Silver Jubilee Volume, Indian Geographical Society, Madras, pp All rights Reserved 173