Table 2 IHA index statistics table before and after a mutation in Jialing River.
From: Hydrologic regime alteration and influence factors in the Jialing River of the Yangtze River, China
IHA indicators | Median value | Hydrological alteration degree | |||
|---|---|---|---|---|---|
Pre-impact | Post-impact | value % | Degree | ||
Group 1 | January (m3 s−1) | 433.5 | 536.5 | 77.38 | H |
February (m3 s−1) | 363.8 | 415.3 | 32.14 | L | |
March (m3 s−1) | 391 | 532 | 66.07 | H | |
April (m3 s−1) | 838.8 | 823 | 17.86 | L | |
May (m3 s−1) | 1668 | 1695 | 20.83 | L | |
June (m3 s−1) | 1565 | 1375 | 15.56 | L | |
July (m3 s−1) | 3650 | 2605 | 77.38 | H | |
August (m3 s−1) | 2975 | 2270 | 69.64 | H | |
September (m3 s−1) | 2733 | 2435 | 69.64 | H | |
October (m3 s−1) | 1990 | 1745 | 43.45 | M | |
November (m3 s−1) | 1085 | 1128 | 20.83 | L | |
December (m3 s−1) | 557 | 596 | 20.83 | L | |
Group 2 | 1-day minimum (m3 s−1) | 328.5 | 274 | 66.07 | H |
3-day minimum (m3 s−1) | 333.3 | 296.7 | 1.786 | L | |
7-day minimum (m3 s−1) | 336.3 | 329.1 | 20.83 | L | |
30-day minimum (m3 s−1) | 349.2 | 402.6 | 57.78 | M | |
90-day minimum (m3 s−1) | 422.1 | 515.6 | 32.14 | L | |
1-day maximum (m3 s−1) | 22,200 | 19,950 | 43.45 | M | |
3-day maximum (m3 s−1) | 18,680 | 16,340 | 20.83 | L | |
7-day maximum (m3 s−1) | 14,660 | 12,090 | 54.76 | M | |
30-day maximum (m3 s−1) | 7605 | 5930 | 26.11 | L | |
90-day maximum (m3 s−1) | 5178 | 3815 | 43.45 | M | |
Base flow index (m3 s−1) | 0.1541 | 0.1951 | 43.45 | M | |
Group 3 | Date of minimum (ds) | 60 | 50 | 31.14 | L |
Date of maximum (ds) | 200 | 210 | 30.67 | L | |
Group 4 | Low pulse count (times) | 2 | 13 | 82.41 | H |
Low pulse duration (ds) | 37.75 | 2 | 63.46 | M | |
High pulse count (times) | 9 | 9 | 24.6 | L | |
High pulse duration (ds) | 6 | 5 | 16.18 | L | |
Group 5 | Rise rate (m3 d−1) | 114.5 | 108.5 | 32.14 | L |
Fall rate (m3 d−1) | − 70 | − 127 | 36.67 | M | |
Number of reversals (times) | 102.5 | 159.5 | 100 | H | |
