Table 4 Summary of morphometric parameters evaluated for classifying the Banki watershed under the proposed RRLCC.
Morphometric parameter (s) | % decrease from the reference year (1977) | Mean decrease (%) | Conservation category | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
1st order | 2nd order | 3rd order | 4th order | 5th order | 6th order | Overall | ||||
Number of streams (Nu) | 88.7 | 86.8 | 87.3 | 95.5 | 100.0 | 100.0 | 88.4 | 77.6 | Critically endangered | |
Total length of streams (Lu) (km) | 79.9 | 49.3 | 60.5 | 54.8 | 100.0 | 100.0 | 70.3 | |||
Drainage density (Dd) (km/km2) | 80 | 49 | 61 | 55 | 100.0 | 100.0 | 74.1 | |||
Ecological entity | Threatened category | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Not evaluated (NE) | Data deficient (DD) | Least concern (LC) | Near threatened (NT) | Vulnerable (VU) | Endangered (EN) | Critically endangered (CR) | Near to extinction (NEX) | Extinct (EX) | ||
Banki watershed | Before assessment (1977) | Yes | Yes | Yes | – | – | – | – | – | – |
After assessment (2021) | No | No | No | – | – | – | Yes | – | – | |
Threatened categories | Criteria | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Extinct (EX) | 1. Entire loss of watershed, i.e., no Nu-Lu-Dd recorded | |||||||||
Near to extinction (NEX) | 1. Only Lu of the main trunk is recorded without Nu and Dd 2. Stream order can not be delineated 3. Extinction of subwatershed(s) | |||||||||
Critically endangered (CR) | 1. Average decrease in Nu-Lu-Dd is > 70% 2. Change in the stream order from 3 to 1, 4 to 2, 5 to 3, 6 to 4, 7 to 5 and so on in the main watershed or subwatershed(s) 3. Extinction of subwatershed(s) | |||||||||
Endangered (EN) | 1. Average decrease in Nu-Lu-Dd is < 70% to > 50% 2. Change in the stream order from 3 to 1, 4 to 2, 5 to 3, 6 to 4, 7 to 5 and so on in the main watershed or subwatershed(s) 3. Extinction of subwatershed(s) | |||||||||
Vulnerable (VU) | 1. Average decrease in Nu-Lu-Dd is < 50% to > 30% 2. Change in the stream order from 3 to 1, 4 to 2, 5 to 3, 6 to 4, 7 to 5 and so on in the main watershed or subwatershed(s) 3. No extinction of subwatershed(s) | |||||||||
Near threatened (NT) | 1. Average decrease in Nu-Lu-Dd is < 30% 2. No change in the stream order 3. No extinction of subwatershed(s) | |||||||||
