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The Effect of Developmental Activities on Water Quality Functions of Bottomland Hardwood Ecosystems: The Report of the Water Quality Workgroup
Published in James G. Gosselink, Lyndon C. Lee, Thomas A. Muir, Ecological Processes and Cumulative Impacts, 2020
Michael L. Scott, Barbara A. Kleiss, William H. Patrick, Charles A. Segelquist, C. Belin, J. Chowning, L. Glenboski, P. Hatcher, D. Hicks, H. Howard, E. Hughes, A. Lucas, D. Walker
These characteristics are influenced by the geomorphic features of bottomland hardwood floodplains which, despite their low topographic relief, are a complex of abandoned river channels and levees, point bar deposits, overflow channels, scour channels, and minibasins (Wharton et al. 1982). We define fetch as the distance or area over which floodwaters interact with a bottomland hardwood floodplain. Sinuosity, or the ratio of stream channel length to downvalley distance (Leopold et al. 1964), refers here to the amount of turning in the travel of water across a site during the rise and recession of flood flows. As the topographic complexity of a site increases, so would the sinuosity and, thus, the fetch of a bottomland hardwood site. Activities such as conversion to agriculture, aquaculture, and pine culture tend to reduce the topographic features of a bottomland hardwood site and would, therefore, reduce the fetch and sinuosity. Similarly, on-site channelization and levee construction would effectively reduce fetch and sinuosity by reducing the extent to which the site would flood. On-site impoundment would inundate many or most topographic features and effectively reduce fetch and sinuosity. Upstream channelization, levee construction, or impoundment would have no obvious direct effect on these characteristics.
The Drainage Basin as the Fundamental Geomorphic Unit
Published in Richard J. Chorley, Introduction to Physical Hydrology, 2019
The ratio between the measured length of a stream channel and that of the thalweg of its valley is a measure of its sinuosity (fig. 2.11.4). Distributions of lengths of streams of each order in a drainage basin are characteristically right-skewed (log-normal) (fig. 2.II.5), and the plot of mean stream lengths of each order (1, 2, 3, … k) in a basin produces an approximation to a direct geometric series (fig. 2.II.6), where the antilog of the regression coefficient is the length ration (Rl).
Probabilistic risk assessment framework for predicting large woody debris accumulations and scour near bridges
Published in Structure and Infrastructure Engineering, 2023
William Hughes, Leana Santos, Qin Lu, Ramesh Malla, Nalini Ravishanker, Wei Zhang
An existing bridge (structure number 100202003002021) located on the Walloomsac River near North Bennington, Vermont, as displayed in Figure 2, is selected for the case study. Based on the and National Bridge Inventory (NBI) (Federal Highway Administration (FHWA), 1992), the bridge was constructed in 1840 and reconstructed in 1991. While the overall bridge condition is reported as satisfactory, its scour susceptibility is not listed, and its waterway adequacy rating indicates potential for occasional water overtopping. The sinuosity of the river, defined as the ratio of curvilinear length to the Euclidian distance between curve endpoints, in the 4 km (2.5 miles) upstream area before branching off upstream, is 1.71. Streams with lower sinuosity closer to one have been found to be more vulnerable (Anderson et al., 2017a). Based on satellite imagery (Environmental Systems Research Institute, 2022b) and analysis of the digital elevation model (DEM), the upstream channel width is estimated as 28 m. The soil in the immediate vicinity of the bridge is classified as fine sandy loam, which has slight erodibility (Soil Survey Staff Conservation, Natural Resources, United States Department of Agriculture, 2021).
Ad-hoc combination and analysis of heterogeneous and distributed spatial data for environmental monitoring – design and prototype of a web-based solution
Published in International Journal of Digital Earth, 2018
Stefan Wiemann, Pierre Karrasch, Lars Bernard
The first application targets at governmental authorities with reporting obligations on the ecological quality of water bodies, for example, in the context of the EU WFD. The determination of the river sinuosity, basically an indicator on its curvature dividing the curve length by the basis length, is chosen as an important hydromorphological parameter with significant influence on the potential biological status of a river. The implemented sinuosity process takes a single geometry, that is, the spatial representation of a river, as input and returns information on the sinuosity for each point on the line considering various possible segment lengths (Karrasch et al. 2015). Thus, technically, the process is only constrained by the selection of at least one feature with linear geometry type. The service response contains a link to the result image, which can be downloaded and used for a detailed inspection and interpretation of the river sinuosity. The corresponding inputs and output of the application are depicted in Figure 7.
Assessment of planform changes of the Ganga River from Bhagalpur to Farakka during 1973 to 2019 using Satellite Imagery
Published in ISH Journal of Hydraulic Engineering, 2022
Sinuosity is an important parameter for describing the dynamic nature of a river. It is the measure of the deviation of flow path from a straight path. It is defined as ‘Ratio of mid-channel length of the widest channel to the overall length of the channel reach measured along a straight line’ (Friend and Sinha 1993). Sinuosity (S) is given as: