Table 2 Numbers of species and individuals (mean±SD) and community indices (mean) from grab samples in the disposal (n=12) and the reference (n=12) areas (endobenthic and sessile epibenthic species only)
From: The impact of harbour sludge disposal on benthic macrofauna communities in the Weser estuary
Signficancea | Disposal area (stations I–IV) | Reference area (stations VI–IX) | |||
|---|---|---|---|---|---|
Mean | ±SD | Mean | ±SD | ||
Species per site | |||||
Total | ** | 5.7 | 4.4 | 10.6 | 6.8 |
Endobenthic only | *** | 3.8 | 2.3 | 7.8 | 5.2 |
Cnidaria | 0.7 | 1.1 | 0.8 | 1.3 | |
Crustacea | *** | 0.7 | 1.0 | 2.0 | 1.3 |
Polychaeta | ** | 2.5 | 1.3 | 5.0 | 3.6 |
Mollusca | * | 1.4 | 1.2 | 2.3 | 1.1 |
Individuals per m2 | |||||
Total | * | 172.8 | 224.6 | 486.5 | 821.1 |
Endobenthic only | ** | 112.6 | 142.5 | 381.8 | 682.0 |
Crustacea | ** | 6.8 | 15.2 | 85.5 | 166.9 |
Polychaeta | 96.3 | 128.8 | 260.9 | 512.5 | |
Mollusca | ** | 53.8 | 130.4 | 118.2 | 175.7 |
Community indices | |||||
Diversity | * | 0.85 | - | 1.15 | - |
Species richness | ** | 0.68 | - | 1.21 | - |
Evenness | 0.68 | - | 0.69 | - | |