Morphometric Parameters

Formula/Definition

References

Area (A)

Plan area of the watershed (km²) GIS software analysis

[7]

Basin perimeter (P)

Perimeter of the watershed (km) GIS software analysis

[7]

Stream order

Hierarchical rank

[10]

Basin length (L_b)

Length of the stream (km) GIS software analysis

[7]

Mean stream length (L_sm)

L_sm = L_u/N_u (km) where,

L_sm = mean stream length

L_u = total stream length of all orders

N_u = total no. of stream segments of order “u”

GIS software analysis

[11]

Stream length ratio (R_L)

R_L = L_u/L_u − 1, where L_u − 1 = the total stream length of its next lower order

[7]

Bifurcation ratio (R_b)

R_b = N_u/N_u + 1, where,

N_u + 1 = no. of segments of the next higher order

[14]

Mean bifurcation ratio (R_bm)

R_bm = average of bifurcation ratio of all orders

[10]

Drainage density (D_d)

D_d = L_u/A, where,

L_u = total stream length of all orders (km)

A = area of the watershed (km²)

[7]

Relief ratio (R_r)

R_r = H/L_b, where,

H = total relief

L_b = basin length

GIS software analysis using DEM

[57]

Stream frequency (F_s)

F_s = N_u/A, where,

N_u = total no. of streams of all orders

A = area of the basin (km²)

[6]

Form factor (R_f)

R_f = A/L_b², where

A = area of the basin (km²)

L_b² = square of the basin length

[7]

Basin relief (B_h)

or

Total relief (H)

B_h = h ? h₁, where,

h = maximum height (m)

h₁ = minimum height (m)

GIS software analysis using DEM

[58]

Elongation ratio (R_e)

, where,

A = area of the basin (km²)

L_b = basin length

[14]

Circularity ratio (R_c)

R_c = 4 × π × A/P² where,

π= 3.14

A = area of the bain (km²)

P = perimeter (km)

[11] [13]

Lemniscate ratio (k)

k = L_b²/4A where,

L_b = basin length (km)

A = area of basin (km²)

[18] [59]

Drainage texture (D_t)

D_t = N_u/P, where

N_u = total no. of stream segments of order “u”

P = perimeter of the watershed (km)

[12]

Dissection index (D_is)

D_is = B_h/R_a, where,

R_a = absolute relief

B_h = basin relief or total relief

[60]

Ruggedness number (R_n)

R_n = D_d*(B_h/1000), where,

B_h = basin relief

D_d = drainage density

[11]

Hypsonetric integral (HI)

, where,

H = the weighted mean elevation

H = maximum elevation

h = minimum elevation

[8] [10] [11]