Quantitative geo-morphometric and land cover-based micro-watershed prioritization in the Tons river basin of the lesser Himalaya

Multi-criteria-based sub-basin prioritization and its risk assessment of erosion susceptibility in Kansai–Kumari catchment area, India

“…Prioritization of morphometric, geology, geomorphic, slope and soil has been assigned from the role of their susceptibility to erosion and percentage area of classified category (Patwary et al 2009;Patel et al 2012;Chauhan et al 2016;Meshram and Sharma 2017). Priority of sub-basin (Sb) is estimated from the rank of compound value (Cp) which is ascribed to the average values of six themes derived…”

“…of stream segments of order 'u', Nu + l = number of segments of the next higher order Schumm (1956) Mean bifurcation ratio (Rbm) Rbm = Average of bifurcation ratios of all orders Strahler (1964) Areal aspect Form factor (Ff) F f = A/L 2 F f = form factor, A = area of the basin (km 2 ), L = basin length (km) Horton (1945Horton ( , 1932 Elongation ratio (Re) Re = 1.128 √A/L Re = elongation ratio, A = area of the basin (km 2 ), L = basin length (km) Schumm (1956) Circularity ratio (Rc) Rc = 4 π A/P 2 Rc = circularity ratio, π = 3.14, A = area of the basin (km 2 ), P = perimeter (km) Miller (1953), Strahler (1964) Shape factor (Bs) Bs = L 2 /A Bs = Shape factor, L = Basin length (km), A = Area of the basin (km 2 ) Horton (1932) Compactness coefficient (Cc) Cc = 0.282 1P/A 0.5 Cc = compactness coefficient, P = perimeter (km), A = area of the basin (km 2 ) Gravelius (1914) Drainage density (D) D = L u /A D = drainage density, L u = total stream length of all orders, A = area of the basin (km 2 ) Horton (1945Horton ( , 1932 Stream frequency (Fs) F s = ∑N u /A F s = stream frequency, ∑N u = total no. of streams of all orders, A = area of the basin (km 2 ) Horton (1945Horton ( , 1932 Drainage texture (Ts) Ts = D d *F s T = drainage texture, D d = drainage density, F s = stream frequency Horton (1945) Constant of channel maintenance (C) C = 1/D d C = constant of channel maintenance, D d = drainage density Schumm (1956) Length of overland flow (Lo) L o = 1/2D d L o = length of overland flow, D d = drainage density Horton (1945) Relief aspect Basin relief (R) R = H − h R = basin relief, H = maximum elevation in meter, h = minimum elevation in meter Schumm and Hadley (1961) Relief ratio (R r ) R r = R∕L Rr = relief ratio, R = basin relief, L = longest axis in kilometre Schumm (1956) Ruggedness number (Rn) Rn = (R × D d )/K Rn = ruggedness number, R = basin relief, D d = drainage density K = A conversion constant 1000 when relative relief is expressed in meter and drainage density in kilometre/square kilometre Schumm (1956) Gradient ratio (Gr) Gr = (a − b)/L Gr = gradient ratio, a = elevation at source, b = elevation at mouth, L = longest axis in kilometre Sreedevi et al (2005) area of high erosion susceptibility and next rank assigned from second highest sub-basin and so on, whereas lowest percentage area of low erosion susceptibility in an individual sub-basin has been ranked '1', second lowest value as given rank '2' and so on (Chauhan et al 2016). Ranking order of geological set-up has been assigned from the highest percentage area of Chotanagpur granite gneiss, Dolma volcanic, epidiorite, ho...…”

“…Higher priority class is associated with a lower composite score, while lowest priority class is concentrated with the highest composite score. Therefore, final priority status and the composite score have been established as a positive relation following equation (Chauhan et al 2016).…”

“…These are important parameters for the detection of indigenous geophysical parameters-based basin prioritization as well as help in effective taking step of sustainable planning and management in every sub-basin (Javed et al 2011;Patel et al 2012;Malik and Bhat 2014). It is noted that basin prioritization does not depend on morphometric, land use/land cover and slope but also depends on the geological structure and soil characteristic (Chauhan et al 2016). Prioritization status is determined by the computation of compound values (Cp) from selected parameters, and then, these values are correlated and superimposed on each and other.…”

“…This hypothesis result predicts the correlation between the priority status of the basin and soil erosion susceptibility in every sub-basin. Therefore, all integrated theme-based prioritization depicts that high soil erosion susceptible zone was concentrated on high priority status based on basin area and vice versa (Gajbhiye et al 2014;Chauhan et al 2016;Meshram and Sharma 2017). Several research works have been conducted about the priority status of the basin, but there has research gap how integrated theme-based prioritization accelerated the soil erosion susceptibility.…”