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Basin morphometry and runoff
Published in Stephen A. Thompson, Hydrology for Water Management, 2017
All measurements in Equation (10.3) should be in the same units, e.g. miles per square mile. The dimensions of D are (L−1). Measurements of drainage density in the United States range from values as low as 3 to 4 mi mi2, to values as high as 1000 to 1300 mi mi2 depending upon the climate and geology of the area (Schumm 1956). A way to think of drainage density is as a measure of the closeness of spacing of stream channels, which approximates the distance water must travel before reaching a stream channel. Water flowing over the ground surface as a nonchannelized, discontinuous sheet of water is called overland flow or sheet flow. Overland flow velocities range from tens to hundreds of meters per hour, with depths of flow between 1 and 10 mm. The length of the overland flow path can be an important control on the timing of runoff from a basin. Overland flow is normally the only source of water to first-order streams, and provides water to higher-order streams from interbasin areas. Figure 10.3 shows four first-order streams and their drainage areas. The interbasin areas between the first-order basins do not drain to the first-order streams but into the second-order stream.
Prioritization of Charwa Watershed Based on Morphometric Analysis Using Remote Sensing and Geospatial Techniques
Published in Surendra Kumar Chandniha, Anil Kumar Lohani, Gopal Krishan, Ajay Krishna Prabhakar, Advances in Hydrology and Climate Change, 2023
Ravi Raj, Aman Kumar, Yempali Priyanka, Pratibha Warwade
Drainage density is determined by the ratio of the total length of all the streams and rivers in all orders decided by the total area of watershed or drainage basin. It is a linear parameter of the morphometric analysis and depends upon both climate and physical characteristics of the drainage basin. It is a very sensitive indicator for the erosion calculation by the effect of topographic characteristics and the stream to the outlet. The unit of drainage density is generally expressed in terms of miles of channel per square mile or km/km which indicates the proximity of the channel spacing, thus providing an idea about the quantity measure of the watershed (Strahler, 1964). It is denoted by (Dd).
Causes, Consequences, and Mitigation of Landslides in the Himalayas
Published in Shruti Kanga, Suraj Kumar Singh, Gowhar Meraj, Majid Farooq, Geospatial Modeling for Environmental Management, 2022
Drainage distribution and density is an important factor in landslide studies (Lee and Choi 2004; Jian and Xiang-Guo 2009; Meraj et al. 2021; Chandel et al. 2021; Bera et al. 2021). Drainage density shows how well or poorly a watershed is drained by stream and also depends upon physical and climatic conditions of the drainage basin. Watershed runoff is affected by the soil infiltration or underlying rock types; impervious ground or exposed bedrock leads to rise in the surface water runoff and therefore to more frequent streams.
Assessment and analysis of morphometric characteristics of Lake Tana sub-basin, Upper Blue Nile Basin, Ethiopia
Published in International Journal of River Basin Management, 2023
Bitew G. Tassew, Mulugeta A. Belete, K. Miegel
Drainage density is the ratio of the total length of the stream in a given drainage basin and the area of that drainage basin (Strahler, 1964). It reflects the interaction between climate and the geological setup (Singh et al., 2019). Horton (1945) also mentioned that there is a high correlation among drainage density, precipitation and evaporation. Drainage density also indicates landscape dissection and runoff potential measurements which determine the length of streams per unit area of a drainage basin. It is a measure of the texture of the network, and indicates the balance between the erosive power of overland flow and the resistance of surface soils and rocks. The factors that affect the drainage density are lithology, climate, topography, soil infiltration capacity and vegetation cover. If the lithologies are less permeable then the drainage densities are higher (Farhan & Anaba, 2016; Horton, 1945; Strahler, 1964). On the other hand, permeable rocks with a high infiltration rate reduce overland flow and consequently drainage density is low (Kaur et al., 2014 Nag & Chakraborty, 2003; Vaidya et al., 2013;).
Flood susceptibility mapping using meta-heuristic algorithms
Published in Geomatics, Natural Hazards and Risk, 2022
Alireza Arabameri, Amir Seyed Danesh, M. Santosh, Artemi Cerda, Subodh Chandra Pal, Omid Ghorbanzadeh, Paramita Roy, Indrajit Chowdhuri
The drainage density on the earth’s surface is directly related to the hydrological process (Yin et al. 2022), and the range varies from 0 to 1.82. High drainage density defines a more vulnerable area or zoning to flood. Water infiltration and evapotranspiration are affected by various types of land use and land cover of any area. Nine types of land use zone have been identified, namely agricultural area, fellow land, built-up area, water bodies, dense forest, scattered forest, mixed forest rangeland, and plantation. Moreover, the geology of any region helps construct river channels and develops the flood plains. The geology of our study area can be classified into nine zones. The topographic position index can be used to determine the ruggedness of the terrain. It can be calculated by comparing each cell slope to the mean slope. The topographic ruggedness index expresses the elevation difference between adjacent cells of a DEM. The value of TRI varies from 0 to 85.28 and another factor, topographic surface texture, refers to both the profile shape and surface roughness which control flood intensity and speed of flowing. Here the value of TST 0 to 68.63 plays a significant role to occur the flood in this region frequently.
Hydro-geomorphic assessment of erosion intensity and sediment yield initiated debris-flow hazards at Wadi Dahab Watershed, Egypt
Published in Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards, 2021
Sara M. Abuzied, Biswajeet Pradhan
For drainage density (Figure 16), the highest NRF was assigned to high density (2.01) followed by moderate density (1.56) (Table 2). Additionally, the highest values of IV were estimated in the very high and high density classes (1.7 and 0.588, respectively). Commonly, a high drainage density creates greater runoff and greater erosional processes. Different characteristics control the drainage pattern of WDW, such as slope, lithologic units, soil types, structural features, and infiltration rate. Mostly, gullies are associated with the stream network to evacuate eroded sediments from upland zones (Conoscenti et al. 2014). Therefore, distance to main streams was considered to reveal the influence of stream network on channel erosion and hence the initiation of debris-flow hazards (Figure 20). The highest NRF was assigned to distances close to main streams (3.137 and 0.994) (Table 2). In addition, the highest values of IV were adopted to the same distances which are close to main streams (1.6 and 0.077, respectively).