| Epifaunal substratum/ available cover |
Greater than 70% of substratum favourable for epifaunal colonization and fish cover; mix of snags, submerged logs, undercut banks, cobble or other stable habitat and at a stage to allow full colonization potential (i.e., logs and snags that are not new fall nor transient). |
40-70% mix of stable habitat; well-suited for full colonization potential; adequate habitat for maintenance of populations; presence of additional substratum in the form of new-fall, but not yet prepared for colonization (may rate at high end of scale). |
20-40% mix of stable habitat; habitat availability less than desirable; substratum frequently disturbed or removed. |
Less than 20% stable habitat; lack of habitat is obvious; substratum unstable or lacking. |
| Score |
20 |
19 |
18 |
17 |
16 |
15 |
14 |
13 |
12 |
11 |
10 |
9 |
8 |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
| Velocity/depth regime |
All four velocity: depth regimes present (slow-deep, slow-shallow, fast-deep, fast-shallow). (Slow is < 0.3 ms-1, deep is > 0.5 m). |
Only three of the four regimes present (if fast-shallow is missing, score lower than if missing other regimes). |
Only two of the four habitat regimes present (if fast-shallow or slow-shallow are missing, score low). |
Dominated by one velocity/depth regime (usually slow-deep). |
| Score |
20 |
19 |
18 |
17 |
16 |
15 |
14 |
13 |
12 |
11 |
10 |
9 |
8 |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
| Sediment deposition |
Little or no enlargement of islands or point bars and < 5% of the bottom affected by sediment deposition |
Some new increase in bar formation, mostly from gravel, sand, or fine sediment; 5-30% of the bottom affected; slight deposition in pools. |
Moderate deposition of new gravel, sand, or fine sediment on old and new bars; 30-50% of the bottom affected; sediment deposits at obstructions, constrictions and bends; moderate deposition of pools prevalent. |
Heavy deposits of fine material, increased bar development; > 50% of the bottom changing frequently; pools almost absent due to substantial sediment deposition. |
| Score |
20 |
19 |
18 |
17 |
16 |
15 |
14 |
13 |
12 |
11 |
10 |
9 |
8 |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
| Channel flow status |
Water reaches base of both lower banks, and minimal amount of channel substratum is exposed. |
Water fills >75% of the available channel; or <25% of channel substratum is exposed. |
Water fills 25-75% of the available channel, and/or riffle substrata are mostly exposed. |
Very little water in channel and mostly present as standing pools. |
| Score |
20 |
19 |
18 |
17 |
16 |
15 |
14 |
13 |
12 |
11 |
10 |
9 |
8 |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
| Channel alteration |
Channelization or dredging absent or minimal; stream with normal pattern. |
Some channelization present, usually in areas of bridge abutments; evidence of past channelization, i.e., dredging, (greater than past 20 years) may be present, but recent channelization is not present. |
Channelization may be extensive; embankments or shoring structures present on both banks; and 40 to 80% of stream reach channelized and disrupted. |
Banks shored with gabion or cement; over 80% of the stream reach channelized and disrupted. Instream habitat greatly altered or removed entirely. |
| Score |
20 |
19 |
18 |
17 |
16 |
15 |
14 |
13 |
12 |
11 |
10 |
9 |
8 |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
| Frequency of riffles (or bends) |
Occurrence of riffles relatively frequent; ratio of distance between riffles divided by width of the stream <7:1 (generally 5 to 7); variety of habitat is key. In streams where riffles are continuous, placement of boulders or other large, natural obstruction is important. |
Occurrence of riffles infrequent; distance between riffles divided by the width of the stream is between 7 to 15. |
Occasional riffle or bend; bottom contours provide some habitat; distance between riffles divided by the width of the stream is between 15 to 25. |
Generally, all flat water or shallow riffles; poor habitat; distance between riffles divided by the width of the stream is a ratio of >25. |
| Score |
20 |
19 |
18 |
17 |
16 |
15 |
14 |
13 |
12 |
11 |
10 |
9 |
8 |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
| Bank stability (score each bank) |
Bank stable; evidence of erosion or bank failure absent or minimal; little potential for future problems. <5% of bank affected. |
Moderately stable; infrequent, small areas of erosion mostly healed over. 5-30% of bank in reach has areas of erosion. |
Moderately unstable; 30-60% of bank in reach has areas of erosion; high erosion potential during floods. |
Unstable; many eroded areas; ’raw‘ areas frequent along straight sections and bends; obvious bank sloughing; 60-100% of bank has erosional scars. |
| Score |
Left bank |
10 |
9 |
|
|
8 |
7 |
6 |
|
|
5 |
4 |
3 |
|
|
2 |
1 |
0 |
|
|
|
| Right bank |
10 |
9 |
|
|
8 |
7 |
6 |
|
|
5 |
4 |
3 |
|
|
2 |
1 |
0 |
|
|
|
| Vegetative protection (score each bank) |
More than 90% of the streambank surfaces and immediate riparian zone covered by native vegetation, including trees, understory shrubs or non-woody macrophytes; vegetative disruption through grazing or mowing minimal or not evident; almost all plants allowed to grow naturally. |
70-90% of the streambank surfaces covered by native vegetation, but one class of plants is not well represented; disruption evident but not affecting full plant growth potential to any great extent; more than one-half of the potential plant stubble height remaining. |
50-70% of the streambank surfaces covered by vegetation; disruption obvious; patches of bare soil or closely cropped vegetation common; less than one-half of the potential plant stubble height remaining. |
Less than 50% of the streambank surfaces covered by vegetation; disruption of streambank vegetation is very high; vegetation has been removed to 5 cm or less in average stubble height |
| Score |
Left bank |
10 |
9 |
|
|
8 |
7 |
6 |
|
|
5 |
4 |
3 |
|
|
2 |
1 |
0 |
|
|
|
| Right bank |
10 |
9 |
|
|
8 |
7 |
6 |
|
|
5 |
4 |
3 |
|
|
2 |
1 |
0 |
|
|
|
| Riparian vegetative zone width (score each bank riparian zone) |
Width of riparian zone >18 m; human activities (i.e., parking lots, roadbeds, clear-cuts, lawns, or crops) have not impacted zone. |
Width of riparian zone 12-18 m; human activities have impacted zone only minimally. |
Width of riparian zone 6- 12 m; human activities have impacted zone a great deal. |
Width of riparian zone <6 m: little or no riparian vegetation due to human activities. |
| Score |
Left bank |
10 |
9 |
|
|
8 |
7 |
6 |
|
|
5 |
4 |
3 |
|
|
2 |
1 |
0 |
|
|
|
| Right bank |
10 |
9 |
|
|
8 |
7 |
6 |
|
|
5 |
4 |
3 |
|
|
2 |
1 |
0 |
|
|
|
A stream multimetric fish index in a large-sized city in south-eastern Brazil
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