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Table 10 Similarity in extracted values and isoline zones for the different parameters from various datasets in comparison to the T50A dataset

From: Evaluation of different digital elevation models for analyzing drainage morphometric parameters in a mountainous terrain: a case study of the Supin–Upper Tons Basin, Indian Himalayas

Sl. No. Dataset Difference class from T50A values Average elevation Relative relief Slope Drainage density Averaged totals Remarks
Difference class range (m) % Basin area Total % Difference class range (m) % Basin area Total % Difference class range (degrees) % Basin area Total % Difference class range (km / sqkm) % Basin area Total %
1 A30 Immediate greater −100 to 0 47.19 85.42 −250 to 0 40.06 99.26 −10 to 0 80.85 94.23 −2 to 0 11.55 50.20 82.28 Very high match
Immediate lesser 0 to 100 38.23 0 to 250 59.20 0 to 10 13.38 0 to 2 38.65
2 A90 Immediate greater −500 to 0 25.60 52.87 −250 to 0 38.53 72.24 −10 to 0 38.65 58.52 −2 to 0 32.01 70.78 63.60 Low match
Immediate lesser 0 to 500 27.27 0 to 250 33.71 0 to 10 19.87 0 to 2 38.77
3 C30 Immediate greater −100 to 0 50.75 65.55 −250 to 0 53.80 93.97 −10 to 0 70.93 82.41 −2 to 0 9.22 47.82 72.44 Moderate match
Immediate lesser 0 to 100 14.80 0 to 250 40.17 0 to 10 11.48 0 to 2 38.60
4 C90 Immediate greater −500 to 0 27.04 54.62 −250 to 0 42.15 69.62 −10 to 0 37.41 50.80 −2 to 0 32.32 71.20 61.56 Low match
Immediate lesser 0 to 500 27.58 0 to 250 27.47 0 to 10 13.39 0 to 2 38.88
5 S90 Immediate greater −100 to 0 48.74 86.23 −250 to 0 62.39 98.94 −10 to 0 80.68 87.65 −2 to 0 39.68 76.85 87.42 Very high match
Immediate lesser 0 to 100 37.49 0 to 250 36.55 0 to 10 6.97 0 to 2 37.17
6 T50D Immediate greater −100 to 0 60.61 94.12 −250 to 0 94.88 99.86 −10 to 0 82.81 84.76 −2 to 0 48.77 78.48 89.31 Highest match
Immediate lesser 0 to 100 33.51 0 to 250 4.98 0 to 10 1.95 0 to 2 29.71
7 T250A Immediate greater −500 to 0 46.95 74.96 −250 to 0 30.60 47.43 −10 to 0 31.43 52.04 −2 to 0 48.55 71.57 61.50 Lowest match
Immediate lesser 0 to 500 28.01 0 to 250 16.83 0 to 10 20.61 0 to 2 23.02
8 T250D Immediate greater −500 to 0 47.16 74.93 −250 to 0 38.64 58.79 −10 to 0 29.67 42.83 −2 to 0 41.85 79.06 63.90 Low match
Immediate lesser 0 to 500 27.77 0 to 250 20.15 0 to 10 13.16 0 to 2 37.21
  1. Differences for each dataset are computed parameter-wise by subtracting from the corresponding values of that same parameter in the T50A database for each of the 1154 grids and isopleth classes are then demarcated on basis of this difference. Thus the immediate greater class (where T50A values are higher) and immediate lesser class (where T50A values are lower) together show areas which are more closely approximate to the values of the surveyed T50A database. If these two ranges combined, cover a greater proportion of the basin area, it implies then that that dataset matches well with the surveyed topographical map database, in terms of the parameters extracted and their ensuing isopleth zones. Perfect matching would give a narrow difference class range around zero covering the total basin area