Upstream Drainage Area Research Articles

Do gravel bed river size distributions record channel network structure?

Bed load sediment particles supplied to channels by hillslopes are reduced in size by abrasion during downstream transport. The branching structure of the channel network creates a distribution of downstream travel distances to a given reach of river and thus may strongly influence the grain size distribution of the long‐term bed load flux through that reach. Here we investigate this hypothesis, using mass conservation and the Sternberg exponential decay equation for particle abrasion, to predict bed material variability at multiple scales for both natural and artificial drainage networks. We assume that over a sufficiently long timescale, no net deposition occurs and that grains less than 2 mm are swept away in suspension. We find that abrasion during fluvial transport has a surprisingly small effect on the bed load sediment grain size distribution, for the simple case of spatially uniform supply of poorly sorted hillslope sediments. This occurs because at any point in the channel network, local resupply offsets the size reduction of material transported from upstream. Thus river bed material may essentially mirror the coarse component of the size distribution of hillslope sediment supply. Furthermore, there is a predictable distance downstream at which the bed load grain size distribution reaches a steady state. In the absence of net deposition due to selective transport, large‐scale variability in bed material, such as downstream fining, must then be due primarily to spatial gradients in hillslope sediment production and transport characteristics. A second key finding is that average bed load flux will tend to stabilize at a constant value, independent of upstream drainage area, once the rate of silt production by bed load abrasion per unit travel distance is equal to the rate of coarse sediment supply per unit channel length (q). Bed load flux equilibrates over a distance that scales with the inverse of the fining coefficient in the abrasion rate law (α) and can be approximated simply as q/3α. Thus the efficiency of particle abrasion sets a fundamental length scale, shorter for weaker rocks and longer for harder rocks, which controls the expression in the river bed of variability in sediment supply. We explore the role of the abrasion length scale in modulating the influence of sediment supply variability in a number of channel network contexts, including individual tributary junctions, a sequence of tributary inputs along a main stem channel, and variable basin shapes and network architecture as expressed by the width function. These findings highlight the need for both data and theory that can be used to predict the grain size distributions supplied to channels by hillslopes.

Channel geometry, median grain size, and stream power in small mountain streams

Small mountain streams are typically affected by the same variables as larger counterparts, but small headwater channels are also coupled with hillslopes. The added degree of system complexity limits extension of existing conceptual and quantitative models of stream response to small mountain streams. Our objective is to determine how the presence of multiple lithologies on channel beds and coarse sediments affect relationships between channel geometry and driving and resisting variables in small mountain streams when the variables are examined at the landscape-scale. We test for systematic scaling of channel geometry, stream power indices, and median bed grain size ( D 50) in headwater streams draining < 10 km 2 and overlying multiple strata on a passive continental margin. Field data were collected from 157 reaches in 32 watersheds. Local strata can be divided into a thick sequence of resistant sandstones and a thick sequence of low resistance, calcareous siltstones and shales with interbedded limestones. Both stratigraphic units are present in every watershed and all streams carry abundant, coarse bed load derived from the resistant unit. Mean widths and gradients of the channels are correlated with upstream drainage area. Unit stream power is not statistically different as a function of rock unit, but channel gradients are lower atop the low resistance unit. D 50 is not correlated with drainage area, but is positively correlated with unit stream power. The correlation between unit stream power and D 50 is evidence for mutual adjustments among gradients, widths, and D 50 as a function of the primary driving force in the drainage area, discharge. The small effect of bed lithology on stream processes and strong relationship between channel geometry, unit stream power, and D 50 implies that available driving forces and grain size are the primary controls on stream processes in the study area. We conclude that future research into system response in this and similar settings should focus on sediment characteristics, production, and flux.

Field determination of the spatial variation of resistance to flow along a steep Alpine stream

Accurate field data have been collected along the Febbraro River (central Italian Alps) during quasi-steady, low-flow conditions to investigate the spatial variations of hydraulic and geomorphologic quantities potentially affecting resistance to flow. Detailed uncertainty analysis and weighted least-squares fitting of simple power function relationships to field-derived data are carried out to identify possible interdependencies between observed variables. Mean flow velocity is found to depend on water-surface slope, bed material particle size, and upstream drainage area, whereas its dependence on hydraulic depth appears less susceptible to quantification. Upstream drainage area is found to explain the variations of hydraulic depth, water-surface slope, Gauckler–Strickler conductance coefficient, and (although less significantly) flow discharge. Specifically, a highly significant positive dependence of the Gauckler–Strickler conductance coefficient on the upstream drainage area is found to exist, although anomalies in the variations of hydraulic depth and flow discharge are observed along the stream. The combined use of uncertainty analysis, hydraulic equations, and geomorphological relationships allows a possible characterization of resistance to flow along a steep Alpine stream and, perhaps more importantly, provides useful guidelines for future investigative efforts. Copyright  2006 John Wiley & Sons, Ltd.

Effects of urbanization on watershed hydrology: The scaling of discharge with drainage area

Research Article| September 01, 2006 Effects of urbanization on watershed hydrology: The scaling of discharge with drainage area Joshua C. Galster; Joshua C. Galster 1Department of Earth and Environmental Sciences, Lehigh University, 31 Williams, Bethlehem, Pennsylvania 18015, USA Search for other works by this author on: GSW Google Scholar Frank J. Pazzaglia; Frank J. Pazzaglia 1Department of Earth and Environmental Sciences, Lehigh University, 31 Williams, Bethlehem, Pennsylvania 18015, USA Search for other works by this author on: GSW Google Scholar Bruce R. Hargreaves; Bruce R. Hargreaves 1Department of Earth and Environmental Sciences, Lehigh University, 31 Williams, Bethlehem, Pennsylvania 18015, USA Search for other works by this author on: GSW Google Scholar Donald P. Morris; Donald P. Morris 1Department of Earth and Environmental Sciences, Lehigh University, 31 Williams, Bethlehem, Pennsylvania 18015, USA Search for other works by this author on: GSW Google Scholar Stephen C. Peters; Stephen C. Peters 1Department of Earth and Environmental Sciences, Lehigh University, 31 Williams, Bethlehem, Pennsylvania 18015, USA Search for other works by this author on: GSW Google Scholar Richard N. Weisman Richard N. Weisman 2Department of Civil and Environmental Engineering, Lehigh University, 19 Memorial Drive West, Bethlehem, Pennsylvania 18015, USA Search for other works by this author on: GSW Google Scholar Geology (2006) 34 (9): 713–716. https://doi.org/10.1130/G22633.1 Article history received: 23 Jan 2006 rev-recd: 29 Mar 2006 accepted: 06 Apr 2006 first online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Joshua C. Galster, Frank J. Pazzaglia, Bruce R. Hargreaves, Donald P. Morris, Stephen C. Peters, Richard N. Weisman; Effects of urbanization on watershed hydrology: The scaling of discharge with drainage area. Geology 2006;; 34 (9): 713–716. doi: https://doi.org/10.1130/G22633.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract This study examines the effects of impervious surfaces within urbanized land on the scaling of river discharge with drainage area. Discharge in a river channel grows as drainage basin area increases following the general equation Q = kAc, where Q is river discharge, k is a measure of river base flow, A is upstream drainage area, and c is the scaling power dependency. Land use is a critical variable in the examination of river discharge; discharge has significant geologic and ecologic influences on fluvial systems. Discharge is assumed to scale linearly or nearly linearly with drainage area (c ∼1), but in spite of its widespread application, the relationship has not been explicitly tested with respect to urbanization. Here we show that in small urban settings the scaling is nonlinear for peak flows. It is proposed that effective water loading occurs through a combination of increased runoff and an increase in the rate of transport to the rivers. These higher discharges in urban rivers have the potential to increase erosion, degrade aquatic habitats, and significantly alter channel forms. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Phylogeography of the cyprinid Squalius aradensis and implications for conservation of the endemic freshwater fauna of southern Portugal

The Iberian cyprinid fauna, characterized by the presence of numerous endemic species, has suffered from significant habitat degradation. The critically endangered Squalius aradensis is restricted to small drainages of southern Portugal, habitats that typically exhibit a characteristic Mediterranean-type heterogeneous hydrological system throughout the year, including alternation of flooding events during winter and complete drought in large river sections during summer. To assess the effect of historical and recent processes on genetic diversity in S. aradensis we examined within- and among-population variability in cytochrome b and six polymorphic microsatellite loci. Estimates of genetic diversity in time and space through the combined use of traditional Phi-/F-statistics, phylogenetic trees, ordination methods and nested clade analysis indicated significant and congruent structuring among populations. Data suggest that the Arade drainage represent the evolutionary centre of the species, with subsequent allopatric fragmentation across drainages. Factors other than isolation by distance strongly affected the within-drainage genetic differentiation observed in these Mediterranean-type drainages, including recent population expansion from a bottleneck event and restricted gene flow imposed by a long-term barrier (brackish water area). Significant correlation was found between S. aradensis allelic diversity and upstream drainage area. The relevance of findings for conservation issues is discussed in relation to local intermittent hydrological conditions, the highly restricted distribution and the critically endangered status of the species.

Modelling habitat requirement of European fishes: do species have similar responses to local and regional environmental constraints?

To test the hypothesis that different species have similar responses to local and regional environmental constraints, we modelled the occurrences of 13 species using a data set of 413 undisturbed river reaches. Three environmental descriptors were considered at the local scale (river slope, river width, and upstream drainage area) and three at the regional scale (mean annual and mean range air temperature and basin unit). Using multiple logistic regression modelling techniques, we correctly predicted the occurrence of 11 of the 13 retained species. The hierarchical partitioning analysis that we used allowed us to jointly consider all possible models in a multiple regression setting and to evaluate the independent explanatory power of each of our five environmental variables. We reject the hypothesis of a common species response to the environmental constraints. Species inhabiting upstream river reaches (bullhead (Cottus gobio), brown trout (Salmo trutta), minnow (Phoxinus phoxinus), and stone loach (Barbatula barbatula)) are more sensitive to basin unit. All species representative of downstream areas (barbel (Barbus barbus), dace (Leuciscus leuciscus), chub (Leuciscus cephalus), gudgeon (Gobio gobio), roach (Rutilus rutilus), bleak (Alburnus alburnus), and perch (Perca fluviatilis)) exhibit a positive continuous response to the drainage area, in agreement with the view of a continuous increase of local richness downstream. River slope is an important variable for all species. Main species habitat requirements are discussed for each species.

Application of the PROMETHEE technique to determine depression outlet location and flow direction in DEM

With the fast growing progress of computer technologies, spatial information on watersheds such as flow direction, watershed boundaries and the drainage network can be automatically calculated or extracted from a digital elevation model (DEM). The stubborn problem that depressions exist in DEMs has been frequently encountered while extracting the spatial information of terrain. Several filling-up methods have been proposed for solving depressions. However, their suitability for large-scale flat areas is inadequate. This study proposes a depression watershed method coupled with the Preference Ranking Organization METHod for Enrichment Evaluations (PROMETHEEs) theory to determine the optimal outlet and calculate the flow direction in depressions. Three processing procedures are used to derive the depressionless flow direction: (1) calculating the incipient flow direction; (2) establishing the depression watershed by tracing the upstream drainage area and determining the depression outlet using PROMETHEE theory; (3) calculating the depressionless flow direction. The developed method was used to delineate the Shihmen Reservoir watershed located in Northern Taiwan. The results show that the depression watershed method can effectively solve the shortcomings such as depression outlet differentiating and looped flow direction between depressions. The suitability of the proposed approach was verified.

Distribution of active rock uplift along the eastern margin of the Tibetan Plateau: Inferences from bedrock channel longitudinal profiles

Current models of long‐term river incision into bedrock suggest that the local rate of differential rock uplift should exert a primary control on the gradient of channel longitudinal profiles. However, discrimination of this effect from the influence of variations in substrate erodibility, sediment flux, precipitation, and transient changes in profile shape has proved difficult in practice. Here we investigate the controls on the spatial distribution of bedrock channel gradients adjacent to the Sichuan Basin in an effort to assess the degree and nature of active deformation along this margin of the Tibetan Plateau. Analysis of river longitudinal profiles utilizing a channel steepness index (a measure of profile gradient normalized for drainage area) reveals a zone of anomalously steep channels adjacent to the topographic front of the plateau margin. Channel profiles are systematically less steep in their headwater reaches on the plateau and in their lower reaches east of the plateau margin. Comparison of steepness indices to mapped lithologic variations reveals that lithology has only a limited influence on channel gradient in this field area. We observe no systematic relationship between steepness indices and upstream drainage area; channels of all size are steeper near the plateau margin. We argue that these systematic changes are not readily explained as a consequence of increased sediment flux or of orographic precipitation. We are led to conclude that steep channel profiles along the topographic front of the plateau reflect active differential rock uplift between this region and the foreland.

Evolution des reseaux hydrographiques au contact Cevennes-Grands Causses meridionaux; consequences sur l'evaluation de la surrection tectonique

Abstract The Mediterranean catchment of the Cevennes (S. France) presents deep incision of the river network (fig. 1 and 2). Combined geomorphology and analyses of the residual sedimentary formations allows to reconstruct a complex history of river network evolution, including capture of tributaries of the Herault River (fig. 1, 2 and 3). The history of uplift of the upstream drainage area could be estimated from the provenance studies of the fluvial and karstic deposits, however river incision is also controlled sea-level changes and differential erosion, which makes reconstruction more complex. Allochthonous clasts types: Analyses of allochthonous deposits on the Grands Causses surface reveals different origin for sediments from the hill top and the Airoles valley (fig. 4 b), which was previously unrecognised. Facies 1 is found on the highest points of the Grands Causses surface (well sorted rounded quartz pebbles in red shale matrix) it corresponds to a weathered residual sediments (dismantling of an ancient cover). Facies 2 is found on the slope of the Airoles Valley (fig. 7). It consists of alluvial crystalline poorly sorted clasts with outsized clasts (up to 50 cm) of quartz-vein, schists in a matrix of shales and sand (weathered granite). Between the hill tops and the Airoles Valley, karstic network presents a sediment fill with clasts reworked from facies 1 and facies 2 (fig. 6). Airoles valley model; an example of diachronic formation of drainage network: The Airoles dry valley stretches on the Grands Causses from the north (700 m) to the south into the present thalweg line of the Vis canyon (500 m) (fig. 1b &amp; 3). Crystalline deposits witness an ancient catchment in the Cevennes. Presently, the catchment in the crystalline basement is disconnected and captured by the Arre River flowing eastwards (fig. 3 &amp; 4a). The profile of the Airoles abandoned valley connects with the present Vis Canyon, therefore, at the time of capture, incision of the Vis canyon had reached its present altitude (fig. 4a). The geomorphologic evolution of this area took place in three stages (fig. 8). 1) The Grands Causses acted as piedmont for the crystalline highlands of the Massif Central (fig. 8A). A latter karstic evolution (tropical climate) allowed the weathered residual sediments (facies 1) (fig. 8A). 2) Incision of the Vis karstic canyon implies that the Herault incision and terraces (facies 2) (fig. 8B) of the Airoles valley occurred during this stage. 3) The Arre valley head propagates westward by regressive erosion and finally captured the Airoles river crystalline catchment (fig. 8C). Consequence for the Cevennes uplift and hydrographic network development: Although the values of present vertical incision in the Vis canyon and in the Arre valley are similar, but they achieved at different time. In addition, the narrow and deep canyon of the Vis is due to vertical incision from the karstic surface of the Grands Causses, whereas the Arre wide valley results from (a younger) lateral slopes retreat from a low Herault base-level. The Vis karstic canyon developed in a similar way to the major karstic canyons of both Mediterranean and Atlantic catchment (i.e. Tarn). This rules out a Messinian Mediterranean desiccation as incision driving mechanism and suggests tectonic uplift of the Cevennes and surrounding areas. The Tarn being already incised by 13 My [Ambert, 1990], it implies a Miocene age for the incision. Conclusion: The amplitude of the vertical incision cannot therefore be used in a simple way to interpret the uplift history of the basement. Consequently, geomorphologic analysis appears to be a prerequisite to distinguish the part played by each factor, and to select the site of uplift measurement.

A spatial model to aggregate point-source and nonpoint-source water-quality data for large areas

More objective and consistent methods are needed to assess water quality for large areas. A spatial model, one that capitalizes on the topologic relationships among spatial entities, to aggregate pollution sources from upstream drainage areas is described that can be implemented on land surfaces having heterogeneous water-pollution effects. An infrastructure of stream networks and drainage basins, derived from 1:250,000-scale digital-elevation models, define the hydrologic system in this spatial model. The spatial relationships between point- and nonpoint pollution sources and measurement locations are referenced to the hydrologic infrastructure with the aid of a geographic information system. A maximum-branching algorithm has been developed to simulate the effects of distance from a pollutant source to an arbitrary downstream location, a function traditionally employed in deterministic water quality models.

Effects of Spatial Accumulation of Runoff on Watershed Response

AbstractThe drainage network accumulates upstream subwatershed runoff into a single downstream response, with runoff accumulating at network junctions. The effects of this accumulation on the magnitude and spatial variability of the downstream response are reviewed for simplified boundary conditions. Runoff parameters are runoff depth and corresponding unit area peak runoff rate. At the subwatershed level these parameters are referred to as d and q, respectively, and they vary from one subwatershed to another. At a downstream location, after accumulation by the drainage network, corresponding parameters are referred to as D and Q. Equations expressing the effects of runoff accumulation are formulated and discussed for uniform rainfall conditions. The review shows that the effects of runoff accumulation gain in importance as the number of upstream subwatersheds and the size of the watershed increase in the downstream direction. The accumulation process cancels extreme values of d and q to yield a representative D and Q value for the entire upstream drainage area. The impact of individual d and q values on the downstream D and Q values in the channel diminishes as the number of upstream subwatersheds increases. This results in a decrease in the spatial variability of D and Q in the downstream direction. The review suggests that the role of spatial variability of upstream d and q in the determination of downstream D and Q diminishes as watershed size increases. However, nonuniform rainfall distributions and storm movement may overshadow the effects of runoff accumulation when watershed size increases beyond the size of the storm.

Measures to be Undertaken in Order to Preserve the Trophic State of the “New Danube” at Vienna in the Case of the Construction of the Vienna-Freudenau Hydropower Plant

“Neue Donau” (=“New Danube”) at Vienna was erected for flood protection reasons, but turned out to be a water resort area close to the Vienna City Center (bathing, swimming, surfing along 40 km of beaches). At Vienna, a hydropower plant on River Danube (Vienna-Freudenau) is under discussion. The work presented was undertaken together with Dokulil, Herzig, Humpesch, Janauer and Kohl (Fleckseder and Humpesch, eds., 1987). This paper discusses various alternatives in order to keep the trophic state of New Danube as is at present, but takes also into account left bank water resources questions as well as the hygienic situation (bathing, swimming, surfing). A comparison of all alternatives indicates that - as eutrophication of New Danube is phosphorus driven -precipitation of P in wastewater treatment in the upstream drainage area is, in respect to the situation of New Danube as well as the overall drainage basin - including the receiving Black Sea - the most meaningful solution.

The downstream dilution of stream sediment anomalies

The following idealized formula relates the metal content of an anomalous stream sediment sample ( Me a) and the upstream drainage area ( A a) with the grade ( Me m) and the surface area ( A m) of the mineralized area, provided the background ( Me b) is known and constant: Me m A m = A a ( Me a — Me b) + A m Me b In deriving the formula, the assumptions are made that within the area represented by the anomalous sample, erosion is uniform and there is no more than one anomalous source, no sampling error, no contamination, and no feedback of metal between sediment and water. The degree to which the ideal formula is approached in actual practice has been checked by field observations at four recently discovered porphyry copper deposits — Cerro Colorado, Casino, Chaucha and Rosemont. It is concluded that within reasonable limits, the assumptions are valid and that the formula has potential applications in the planning of sediment sample layouts, and in the interpretation of sediment sample data.

Geomorphology and hydrology of Karst drainage basins and cave channel networks in east central New York

Surface water in the karst drainage basins of east central New York is collected by swallow holes on upland surfaces. Free surface streams, flowing through meandering cave conduits, provide links between the upland surface catchments and large karst springs draining into the major river valleys. Flow through the conduits fluctuates markedly with surface runoff. Mean velocities of 0.5 ft/sec were determined during a period of rapid snowmelt by dye tests. The cave conduits form an integral part of a drainage organization characterized by Horton's hierarchy stream numbers, lengths, and drainage areas. The conduits, the highest‐order streams in the hierarchy, have meandering reaches with wavelengths directly related to up‐stream drainage area and contributed runoff. Both the morphology of the cave channels and the hydrology of the karst drainage basins are strikingly similar to those observed in surface water stream systems.