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Streams: Perennial and Seasonal
Published in Yeqiao Wang, Wetlands and Habitats, 2020
Daniel von Schiller, Vicenç Acuña, Sergi Sabater
In addition to classifying streams by the permanence of their flow, they are often classified by stream order. The most common method for ordering streams is the Strahler classification system (Figure 9.2).[6]In this hierarchical method, the smallest streams are assigned first order. The order of the streams increases when two streams of the same order join. Streams of lower order joining a higher order stream do not change the order of the higher stream. Based on their order, streams are typically classified as small size (first to third order), medium size (fourth to sixth order), or large size (higher than seventh order). Within a drainage area, low-order streams are more frequent than high-order streams and comprise the longest part of the total stream network. Stream order is positively related to physical characteristics such as stream size, discharge, and drainage area. Therefore, it is a simple and informative classification system. Its major drawback is that it is often difficult to determine the perennial first-order streams on maps.
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Published in Carl W. Hall, Laws and Models, 2018
Keywords: drainage, logarithm, numbers, stream HORTON, Claude Wendell, twentieth century (b. 1915), American geologist Sources: Bates, R. L. and Jackson, J. A. 1980. 1987. See also STREAM GRADIENTS; STREAM NUMBERS STREAM NUMBERS, LAW OF (1945) A general law expressing the inverse geometric relation between stream order and the number of streams of each order, in a given drainage basin. The law is expressed as a linear regression of logarithm of number of streams on stream order, the negative regression coefficient being the logarithm of the bifurcation ratio. The stream order is the designation by a dimensionless integer series the relative position of stream segments in a drainage network: the smallest, unbranched tributary, terminating at the outer point designated as order one, with that stream terminating at a single stage is the highest order and determines the order of the stream bed. Keywords: bifurcation ratio, drainage, order, stream HORTON, Claude Wendell, twentieth century (b. 1915), American geologist Sources: Bates, R. L. and Jackson, J. A. 1980. 1987. STRESS-OPTIC LAW IN TWO DIMENSIONS In a transparent isotropic plate in which the stresses are two-dimensional and within the elastic limit, the phase difference or relative retardation in wave length between the rectangular wave components traveling through it and produced by temporary double refraction is: Rt = Ct (p – q) where Rt C t p and q = = = = relative retardation in wavelength stress-optic coefficient thickness of the plate principle stresses
Characteristics of Watershed
Published in Sandeep Samantaray, Abinash Sahoo, Dillip K. Ghose, Watershed Management and Applications of AI, 2021
Sandeep Samantaray, Abinash Sahoo, Dillip K. Ghose
Geomorphology of the basin plays a significant part in conversion of water from terrestrial regions to the channels (streams) and also from channel of one order to another. It can be easily found out by the contour and drainage maps of the basin. The order, the length, the slope and the profile of the channel, and also the density of drainage are very common characteristics of a channel, significant in the estimation of the hydrologic practices of the river basin (Hack, 1957). These features of a watershed depend upon stream order. Stream order is a measure of stream degree channelled through a watershed. Stream length is denoted by its order like first, second, third order etc.
Urbanisation gradients, riparian-loss and contaminant effects on macroinvertebrate distribution within a tropical river (Nigeria)
Published in Chemistry and Ecology, 2022
Andem B. Andem, Oju R. Ibor, Enewan E. Oku, Sunday B. Ekanem, Azubuike V. Chukwuka, Aina O. Adeogun
The concept of stream order identifies and classifies types of streams based on their numbers of tributaries, which in turn can be used to infer their risks to pollution. First-order streams, for instance, have no concentrated flow coming from upstream sources thus, inputs are predominantly from overland flow, which increases their susceptibility to non-point source pollution effects [91]. The incidence of first-order streams across all stations of the urban stretch of Calabar River, immediately suggests that most of the streams in the urban watershed had interrupted tributaries, which disallows the concentrated flows from the headwaters of the watershed into the river. More important is the fact that areas along the urban watershed with depleted riparian areas (S1 and S2) were characterised by the first-order stream flows compared to stations with wider riparian vegetation width (S3 and S4). Since first-order streams are largely fed by overland flows, riparian areas and surface water receiving supply from first-order streams are more likely to receive complexation of contaminants from impervious urban surfaces. It has been demonstrated that loss of riparian vegetation and increased impervious areas due to urbanisation could alter catchment hydrology and stream velocity, which in turn affects dissolved oxygen levels and organic matter retention [16].
Assessment of morphometric and hypsometric study for watershed development using spatial technology – a case study of Wardha river basin in Maharashtra, India
Published in International Journal of River Basin Management, 2021
Chaitanya Pande, Kanak Moharir, Rajeshwari Pande
Stream ordering analysis is a simple step of analysis of drainage in the Wardha river basin; the stream ordering has been suggested for watershed planning (Strahler 1964). In this study, stream ordering was carried out using Strahler’s method of stream calculation from DEM data in the Arc GIS 10.3 software. The drainage ordering depends on drainage and the streams network was extracted from DEM data using Arc Hydro Tools. Streams that originate at a source are defined as the first stream order. In the study area, seven stream orders are observed and observed that the maximum drainage frequency is in the first-order drainage at the Wardha river basin (Table 1, 3 and Figure 4). It is identified that there is a reduction in the drainage quantity as the drainage order increases at the Wardha river basin.
Types of dry-season stream pools: environmental drivers and fish assemblages
Published in Inland Waters, 2020
Maria Ilhéu, Janine da Silva, Manuela Morais, Paula Matono, João Manuel Bernardo
Regional scale variables, in particular stream order and distance to the main river, play a relevant role in the fish species distribution and assemblage structure (e.g., Leftwich et al. 1997, Torgersen et al. 1999, Labbe and Fausch 2000) also in dry season stream pools. The location of pools within the river system and the proximity to larger and more persistent waterbodies acting as potential propagule sources are relevant factors of species diversity, as observed in other studies (Ricklefts and Schluter 1993), and determine the pattern and distribution of fish species. Species richness increased with stream order, mostly because of the presence in the downstream reaches of large, more persistent, and benign pools.