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Table 11. Template for an environmental flow monitoring program designed for the Lesotho Highlands Water Project (modified from LHDA 2003). The zones include the aquatic, lower wetbank, upper wetbank, lower dynamic, and tree/shrub zones (Metsi Consultants 2000a).
| | | |
| Indicator |
|
Category A |
|
Category B |
|
Category C |
|
Category D |
|
Category E/F |
|
|
Pristine |
|
Near natural |
|
Moderately modified |
|
Significantly modified |
|
Severely modified |
| |
|
Geomorphology /hydraulics |
|
Instream habitat diversity |
|
Full natural diversity |
|
5–15% loss |
|
15–40% loss |
|
40–70% loss |
|
> 70% loss |
|
| Pool depth |
|
Natural |
|
5–15% loss |
|
15–40% loss |
|
40–70% loss |
|
> 70% loss |
|
| Bank area eroded or collapsed |
|
< 5% |
|
5–10% |
|
10–20% |
|
20–40% |
|
> 40% |
|
| Water quality |
|
| Change in mean monthly temperature |
|
Natural |
|
< 3° |
|
< 4° |
|
< 5° |
|
< 6° |
|
| Change in annual pH range |
|
Natural |
|
< 0.5 pH units |
|
< 1.0 pH units |
|
< 1.5 pH units |
|
< 2 pH units |
|
| Total Rapid Biological Assessment (SASS) Score |
|
Unknown |
|
> 95 |
|
94–70 |
|
69–45 |
|
< 45 |
|
| Vegetation |
|
| Zone definition |
|
All present and distinct |
|
All present and distinct |
|
Loss of < 2 zones and/or zone definition less distinct |
|
Loss of < 3 zones and/or zone definition indistinct |
|
No definition |
|
| Species composition of riparian vegetation |
|
Full complement |
|
Change in ratios of indigenous species |
|
Dominated by hardy indigenous species and/or exotic species |
|
Dominated by exotics and/or weedy indigenous species |
|
Dominated by one or two species, often > 80% exotics OR no plants |
|
| Growth forms |
|
Full array of growth forms |
|
5–10% reduction |
|
11–25% reduction |
|
26–50% reduction |
|
> 50% reduction |
|
| Fish |
|
| Community composition |
|
Full complement of native species in natural proportions; no exotic species |
|
Full complement of native species, plus very low numbers of exotic species |
|
Noticeable shifts in structure of native fish community, moderate numbers of exotic species |
|
Very few native fish species and/or exotic fish dominate |
|
Very few fish species, dominated by exotic species |
| | |
|