Publication details
Sediment flux conditions in the connective middle-mountain river basin – a case study of the Černá Opava River
| Authors | |
|---|---|
| Year of publication | 2016 |
| Type | Article in Proceedings |
| Conference | Students in Polar and Alpine Research Conference 2016 |
| MU Faculty or unit | |
| Citation | |
| web | https://www.researchgate.net/publication/301788783_Proceedings_Students_in_Polar_and_Alpine_Research_Conference_2016?channel=doi&linkId=57286a6608ae586b21e3f9d2&showFulltext=true |
| Doi | http://dx.doi.org/10.13140/RG.2.1.4703.8320 |
| Field | Earth magnetism, geography |
| Keywords | Bed load, Connectivity, Field survey, Sediment flux, Černá Opava River |
| Description | Upper reaches of rivers are very important in a context of the whole river basin, because this represents zones of erosion. Eroded material is transported downstream the river basin. High-gradient streams are mostly situated in the mountains or in the forested uplands. The Černá Opava River Basin represents one of the examples of connective middle-mountain river basins in the Czech Republic. Studied river basin is located in Hrubý Jeseník Mountains in the Eastern Sudetes and its area is 58.9 km2. The Černá Opava River is 18.6 km long and this river basin is interwoven with a many tributaries. The sources of water are primarily from rainfall and spring snowmelt. Maximum flow rates are in the spring or summer due to flash floods. Typical characteristic for this river basin is variable topography (1204 – 529 m a. s. l.). The Černá Opava River is a high gradient stream with mean channel slope 26.8 ‰ with V shape cross profiles on the upper segment of the river and on the tributaries. Almost 60 % of the valley network is connective (Brierley et al. 2006), which means very close contact between slopes and channels (slope-channel coupling phenomenon; Wistuba 2014). This contribution presents a comprehensive information about existing findings about this river basin. Field survey started in 2012 and continues every year. The main goal of this contribution is to identify sediment sources, to define the areas of erosion and sediment accumulation for the selected streams and to clarify sediment transport downstream the river basin together with description of the blockages in sediment transport. Geomorphological classification based on Montgomery-Buffington (1998) was carried out at the beginning of the field survey in summer season 2012 – 2013 (Ondráčková 2013). The Černá Opava River has a straight channel pattern with a hint of meandering and many reaches with step-pool character (4.3 %), parts with channel bars, or parts with bedrock channel pattern (2.7 %). Dominant type of is plane-bed channel especially on the lower reach of the Černá Opava River (76.3%). Sediment sources for the Černá Opava River were divided into three groups. As point sources (local cut bank, root balls, sediment accumulation), as linear sources (channel reaches with bedrock erosion) and as the potential areas (Fig. 1.). Material moves down the river basin, but the transport is not continuous. Although Černá Opava River basin is located in the Protected Landscape Area Jeseníky (PLA Jeseníky), sediment transport is disrupted due to the human impact in the channel and close river landscape. Anthropogenic influence is primarily at the end of the river in the Vrbno city (concrete steps, dikes, wooden log steps, …). |