A Field Guide to British Rivers. George Heritage
Читать онлайн книгу.
Based on Leopold and Wolman (1957). © John Wiley & Sons).
Table 2.1 River types identified by Montgomery and Buffington (1997) along with their key attributes.
Source: Modified from Montgomery and Buffington (1997). © John Wiley & Sons.
| Attribute | Channel type | |||||||
|---|---|---|---|---|---|---|---|---|
| Braided | Regime | Pool‐riffle | Plane‐bed | Step‐pool | Cascade | Bedrock | Colluvial | |
| Typical bed material | Variable | Sand | Gravel | Gravel cobble | Cobble boulder | Boulder | n/a | Variable |
| Bedform pattern | Lateral oscillation | Multi layered | Lateral oscillation | None | Vertical oscillation | None | Variable | |
| Reach type | Response | Response | Response | Response | Transport | Transport | Transport | Source |
| Dominant roughness elements | Bedforms (bars, pools) | Sinuosity bedforms (dunes, ripples, bars) Banks | Bedforms (bars, pools) Grains Large wood Sinuosity Banks | Grains, Banks | Bedforms (steps, pools) Grains Large wood Banks | Grains Banks | Boundaries (bed, banks) | Grains Large wood |
| Dominant sediment sources | Fluvial Bank failure Debris flows | Fluvial Bank failure Inactive channel | Fluvial Bank failure Inactive channel Debris flows | Fluvial Bank failure Debris flows | Fluvial, Hillslope Debris flows | Fluvial Hillslope Debris flows | Fluvial Hillslope Debris flows | Hillslope Debris flows |
| Sediment storage elements | Overbank bedforms | Overbank bedforms inactive channel | Overbank bedforms inactive channel | Overbank inactive channel | Bedforms | Lee and stoss sides of obstructions | Bed | |
| Typical slope | <0.03 | <0.001 | 0.001> <0.02 | 0.001> <0.03 | 0.03> <0.08 | 0.08> <0.3 | Variable | >0.2 |
| Typical confinement | Unconfined | Unconfined | Unconfined | Variable | Confined | Confined | Confined | Confined |
| Pool spacing (channel widths) | Variable | 5–7 | 5–7 | none | 1–4 | <1 | Variable | Variable |
Table 2.2 Additional river types to those listed in Table 2.1, with channel slope as a discriminator.
| Reference | Pool | Glide | Riffle | Rapid | Cascade |
|---|---|---|---|---|---|
| Bisson et al. (1988) | S < 0.04 | S > 0.04 | S > 0.04 S < 0.16 | ||
| Sullivan (1986) | S < 0.01 | S > 0.01 S < 0.02 | S > 0.01 S < 0.04 | S > 0.04 | S ~ 0.068 |
| Grant et al. (1990) | S ~ 0.005 | S < 0.02 | S ~ 0.011 | S ~ 0.029 | S ~ 0.055 |
| Wood‐Smith and Buffington (1996) | Closed topographic depression | S > 0.02 S < 0.04 | S > 0.04 | ||
| Montgomery and Buffington (1997) | S ~ 0.012 | S > 0.0015 S < 0.04 | S > 0.02 S < 0.076 | S ~ 0.11 |
Figure 2.3 The River Styles typology
(Source: Based on Brierley and Fryirs (2005). © John Wiley & Sons).
2.3.3 River Styles Framework
The River Styles framework (Brierley and Fryirs 2005) develops a more holistic view of fluvial systems, providing a geomorphic