Relevant bibliographies by topics / Intermittent Stream

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  3. Books
  4. Book chapters
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Academic literature on the topic 'Intermittent Stream'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 February 2022

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Journal articles on the topic "Intermittent Stream"

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Poff, N. LeRoy, and J. V. Ward. "Implications of Streamflow Variability and Predictability for Lotic Community Structure: A Regional Analysis of Streamflow Patterns." Canadian Journal of Fisheries and Aquatic Sciences 46, no. 10 (October 1, 1989): 1805–18. http://dx.doi.org/10.1139/f89-228.

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Long-term discharge records (17–81 yr) of 78 streams from across the continental United States were analyzed to develop a general quantitative characterization of streamflow variability and predictability. Based on (1) overall flow variability, (2) flood regime patterns, and (3) extent of intermittency, 11 summary statistics were derived from the entire record for each stream. Using a nonhierarchical clustering technique, nine stream types were identified: harsh intermittent, intermittent flashy, intermittent runoff, perennial flashy, perennial runoff, snowmelt, snow + rain, winter rain, and mesic groundwater. Stream groups separated primarily on combined measures of intermittency, flood frequency, flood predictability, and overall flow predictability, and they showed reasonable geographic affiliation. A conceptual model that incorporates the nine stream clusters in a hierarchical structure is presented. Also, the positions of the 78 streams in a continuous three-dimensional flow space illustrate the wide range of ecologically important hydrologic variability that can constrain ecological and evolutionary processes in streams. Long-term daily streamflow records are a rich source of information with which to evaluate temporal and spatial patterns of lotic environments across many physiographic and ecographic regions. Relative positions of streams in flow space provide a conceptual framework for evaluating a priori the relative importance of abiotic and biotic factors in regulating population and community processes and patterns.
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Piano, Elena, Alberto Doretto, Elisa Falasco, Laura Gruppuso, Francesca Bona, and Stefano Fenoglio. "Flow intermittency negatively affects three phylogenetically related shredder stoneflies by reducing CPOM availability in recently intermittent Alpine streams in SW-Italian Alps." Hydrobiologia 847, no. 19 (September 12, 2020): 4049–61. http://dx.doi.org/10.1007/s10750-020-04399-4.

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Abstract Several Alpine streams are currently facing recurrent summer drying events with detrimental consequences on stream detritivores, i.e., shredders, due to negative effects via changes the organic matter (CPOM) availability. We examined the ecological requirements of three phylogenetically related shredder genera belonging to the family of Nemouridae (Plecoptera), namely Nemoura, Protonemura and Amphinemura, in 14 Alpine streams recently facing recurrent summer flow intermittency events. We evaluated the overlap among their ecological niches measured in terms of hydraulic stress, substrate composition, changes in CPOM availability and competition with other shredder taxa (i.e., presence of individuals of other shredders) and we examined potential changes in their ecological niches between permanent and intermittent sites. The ecological niches of Protonemura and Amphinemura overlap broadly, but not with Nemoura, suggesting only partial potential competition. The reduced CPOM availability decreased the individual abundance of the three genera in intermittent sites, where they consistently preferred microhabitats with high CPOM availability and low competition with other shredder taxa, possibly due to food limitation. Overall, our results emphasize how the negative effect of flow intermittency on shredders in Alpine streams is mainly due to the decrease in CPOM availability, with consequent potential bottom up effects on stream ecosystem functionality.
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Stanish, Lee F., Tyler J. Kohler, Rhea M. M. Esposito, Breana L. Simmons, Uffe N. Nielsen, Diana H. Wall, Diana R. Nemergut, and Diane M. McKnight. "Extreme streams: flow intermittency as a control on diatom communities in meltwater streams in the McMurdo Dry Valleys, Antarctica1This article is derived from a special session entitled “A New Hydrology: Inflow Effects on Ecosystem Form and Functioning” that took place at the February 2011 ASLO Aquatic Sciences conference in San Juan, Puerto Rico." Canadian Journal of Fisheries and Aquatic Sciences 69, no. 8 (August 2012): 1405–19. http://dx.doi.org/10.1139/f2012-022.

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In the McMurdo Dry Valleys of Antarctica, stream biota is limited by the brief availability of liquid water. The benthic microbial mats harbor diatoms that have adapted to hydrologic stresses, including numerous endemic species. We found a strong relationship between diatom community composition and flow intermittency in a data set including seven streams that spanned a gradient in flow intermittency. In particular, two genera represented by numerous endemic species in Dry Valley habitats, Hantzschia and Luticola , had high abundances in moderately and highly intermittent streams, respectively. The Shannon Index of diversity was greatest in streams with intermediate flow intermittency, with lower diversity in more stable streams resulting from lower evenness, and lower diversity in highly intermittent streams resulting from lower richness. These results indicate that multiple metrics of biodiversity may be useful in assessing the response of diatom communities to changing hydrologic regime. We propose that flow intermittency acts as a species filter that increases habitat heterogeneity in Dry Valley streams and may allow endemic species to persist. Future Antarctic warming may alter diatom community composition and habitats that act as refugia for desiccation-tolerant taxa.
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Price, Karen, Arlene Suski, Joanna McGarvie, Barbara Beasley, and John S. Richardson. "Communities of aquatic insects of old-growth and clearcut coastal headwater streams of varying flow persistence." Canadian Journal of Forest Research 33, no. 8 (August 1, 2003): 1416–32. http://dx.doi.org/10.1139/x03-089.

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Headwater streams, varying in flow persistence from ephemeral to intermittent to perennial, provide the tightest coupling between water and land, yet they often receive the least protection during forest management. We described communities of aquatic insects in perennial, intermittent, and ephemeral channels surrounded by old-growth forest and 4- to 8-year-old clearcuts in Clayoquot Sound, British Columbia, to determine whether temporary streams have unique aquatic communities and to examine the short-term impacts of harvesting. We measured flow persistence, stream size, canopy cover, organic detritus, and algal biomass in 19 streams. We sampled aquatic invertebrates with a combination of emergence cages and kicknet samples. Temporary and old-growth streams had more organic detritus and a higher abundance of shredders. Perennial and clearcut streams had a higher abundance of some algal grazers, but not higher algal biomass. Insect richness was similar in intermittent and perennial streams of each seral stage but lower in ephemeral streams. Intermittent streams contained four taxa not found in the other stream classes; perennial and ephemeral streams had none. Communities of aquatic insects differed between streams surrounded by clearcuts and old growth, and varied with continuity of flow.
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Robson, Belinda J. "Role of residual biofilm in the recolonization of rocky intermittent streams by benthic algae." Marine and Freshwater Research 51, no. 7 (2000): 725. http://dx.doi.org/10.1071/mf00012.

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Human use of stream flow for water supply may increase the duration and/or frequency of dry periods in intermittent streams, but there is little information on the effect of this change on in-stream flora or fauna. To predict the effects of dry periods on stream biota, it is necessary to understand the relative roles of various sources of recolonization. A transplant experiment was used to test the hypothesis that the dry residual algal biofilm on stones in intermittent streams is an important source of algal growth when the streams are re-wetted. Two sites were chosen, one on each of two intermittent streams in south-eastern Australia. Rocks at the sites differed in the amount of naturally occurring residual biofilm on them. Forty rocks were transplanted between the sites and counts of algal densities were made from samples taken one and five weeks after flow recommenced. At one of the sites, where the biofilm was dominated by Cyanobacteria, dry residual biofilm strongly influenced the developing algal community at both one and five weeks after flow recommenced. At the other site the influence of dry biofilm was limited after five weeks, implying that other sources of algal recolonization were influential there.
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Burrows, Ryan M., Helen Rutlidge, Dominic G. Valdez, Michael Venarsky, Nick R. Bond, Martin S. Andersen, Brian Fry, Stefan M. Eberhard, and Mark J. Kennard. "Groundwater supports intermittent-stream food webs." Freshwater Science 37, no. 1 (March 2018): 42–53. http://dx.doi.org/10.1086/696533.

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Goodrich, D. C., W. G. Kepner, L. R. Levick, and P. J. Wigington. "Southwestern Intermittent and Ephemeral Stream Connectivity." JAWRA Journal of the American Water Resources Association 54, no. 2 (March 1, 2018): 400–422. http://dx.doi.org/10.1111/1752-1688.12636.

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Clarke, Amber, Ralph Mac Nally, Nick Bond, and P. S. Lake. "Flow permanence affects aquatic macroinvertebrate diversity and community structure in three headwater streams in a forested catchment." Canadian Journal of Fisheries and Aquatic Sciences 67, no. 10 (October 2010): 1649–57. http://dx.doi.org/10.1139/f10-087.

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Drying can be a common disturbance affecting macroinvertebrate communities in headwater streams. Whether intermittent and ephemeral streams have a lower diversity and (or) unique assemblage structure relative to physically similar and nearby perennial streams is still debated. We investigated changes in the diversity and assemblage composition of aquatic macroinvertebrates occupying debris dams in three headwater streams with a gradient of flow permanence (perennial, intermittent, and ephemeral) during a dry period in the austral summer of 2007 and a wet period in the spring of 2008. In the dry period, mean taxon richness and abundance in debris dams were lower in the intermittent and ephemeral streams than in the perennial stream, and the length of time without connected surface flow appeared to produce different patterns in community composition. However, during the wet period, mean taxon richness, abundance, and community composition of macroinvertebrates were very similar among the three streams. Hierarchical Bayesian modeling showed evidence for a strong effect of permanence on taxon richness, abundance, and evenness within debris dams. Taxa from the perennial stream were extremely efficient at colonizing seasonally dry nearby streams. Differences in assemblage structure between these temporary and permanent headwater streams may only arise seasonally and also appear related to flow permanence.
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Butturini, A., S. Bernal, S. Sabater, and F. Sabater. "The influence of riparian-hyporheic zone on the hydrological responses in an intermittent stream." Hydrology and Earth System Sciences 6, no. 3 (June 30, 2002): 515–26. http://dx.doi.org/10.5194/hess-6-515-2002.

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Abstract. Stream and riparian groundwater hydrology has been studied in a small intermittent stream draining a forested catchment for a system representative of a Mediterranean climate. The relationship between precipitation and stream runoff and the interactions between stream water and the surrounding riparian groundwater have been analysed under a wide spectrum of meteorological conditions. The hypothesis that the hydrological condition of the near-stream groundwater compartment can regulate the runoff generation during precipitation events was tested. Stream runoff is characterised by a summer dry period, and precipitation input explained only 25% of runoff variability over the study period (r2 =0.25, d.f.=51, p<0.001). The variability of precipitation v. stream runoff is explained partly by the hydrogeological properties of the riparian near-stream zone. This zone is characterised by high hydrological conductivity values and abrupt changes in groundwater level in summer. The summer dry period begins with a rapid decrease in near-stream groundwater level, and ends just after the first autumnal rain when the original groundwater level recovers suddenly. Within this period, storms do not cause major stream runoff since water infiltrates rapidly into the riparian compartment until it is refilled during the subsequent winter and spring; then the precipitation explains the 80% of the stream runoff variability (r2=0.80, d.f.=34, p<0.001). These results suggest that the hydrological interaction between the riparian groundwater compartment and the stream channel is important in elucidating the hydrological responses during drought periods in small Mediterranean streams. Keywords: riparian zone, groundwater hydrology, runoff, intermittent stream, Mediterranean climate
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Bernal, S., and F. Sabater. "Changes in discharge and solute dynamics between a hillslope and a valley-bottom intermittent streams." Hydrology and Earth System Sciences Discussions 8, no. 5 (October 27, 2011): 9505–36. http://dx.doi.org/10.5194/hessd-8-9505-2011.

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Abstract. We investigated differences on stream water flux as well as on chloride, carbon and nitrogen dynamics between two semiarid nested catchments, one at the hillslope and the other one at the valley-bottom. The two streams were intermittent, yet only the valley-bottom stream was embraced by a riparian forest and a well-developed alluvium with highly conductive coarse sediments. We found that stream water flux decreased by more than 40% from the hillslope to the valley-bottom during hydrological transition periods (from dry-to-wet and from wet-to-dry conditions), coinciding with periods when stream-to-aquifer fluxes prevailed. During the hydrological transition period, stream export of chloride, nitrate, and dissolved organic carbon decreased 34–97% between the hillslope and the valley-bottom catchments. There was a strong correlation between monthly differences in stream discharge and in stream Cl− export between the two catchments. In contrast, monthly differences in stream export for bio-reactive solutes were only partially explained by stream discharge. In annual terms, stream nitrate export from the valley-bottom catchment (0.32 ± 0.12 kg N ha−1 yr−1 – average ± standard deviation) was 30–50% lower than from the hillslope catchment (0.56 ± 0.32 kg N ha−1 yr−1). Although the riparian forest could be an extra source of organic matter to the valley-bottom stream, the annual export of dissolved organic carbon was similar between the two catchments (1.8 ± 1 kg C ha−1 yr−1). Our results suggested that stream hydrology was a strong driver of stream solute export during the hydrological transition period, and that hydrological retention in the alluvial zone could contribute to reduce stream water and solute export under semiarid conditions in the valley-bottom stream.
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Dissertations / Theses on the topic "Intermittent Stream"

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Bernal, Berenguer Susana. "Nitrogen storm responses in an intermittent Meditterranean stream." Doctoral thesis, Universitat de Barcelona, 2006. http://hdl.handle.net/10803/1436.

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The amount of dissolved inorganic nitrogen delivered to streams and groundwater has substantially increased in the last decades due to anthropogenic impacts. This fact has stimulated research on processes related to the nitrogen cycling in order to elucidate the ability of terrestrial and aquatic ecosystems in controlling nitrogen loads. Some of these studies pointed out during storms streamwater chemistry is significantly altered. However, because of the inherent difficulty of an extensive field experimental setting for dealing with episodic storms, studies focused on hydrological processes or stream solute dynamics during storms rely on a very limited number of events. Hydrobiogeochemical processes have been mainly studied in temperate experimental catchments and little attention has been paid to Mediterranean catchments. Recent studies have stressed the fragility of Mediterranean regions in front of the global change and because of that Mediterranean regions should become hot spots for present and future studies.
The main goal of the present thesis was to study the variability of nutrient dynamics, in particular nitrogen, during stormflow in relation to baseflow conditions in Fuirosos, an intermittent stream draining a small Mediterranean catchment (Part I). As a secondary objective (Part II), solute dynamics in Fuirosos were compared with those measured at one of its main tributaries, the Grimola stream. Biotitic granodiorite was an important fraction of the Fuirosos catchment, whereas the Grimola catchment was underlain by leucogranite. The Fuirosos stream had an alluvial zone and it was flanked by a well developed riparian forest, whereas the Grimola stream had not a significant alluvial zone, neither a well developed riparian area. Thereby, the effect of (i) catchment size, (ii) lithology and (iii) the presence of an alluvial-riparian zone on stream hydrogrochemistry were assessed by comparing the Fuirosos and Grimola streams.
The Fuirosos Stream Watershed, a relatively undisturbed Mediterranean ecosystem that can not be considered a N-saturated catchment, leaks to the stream most of the nitrogen loss in the form of nitrate (57 %). This figure contrast with that reported for other pristine tropical and humid catchments where nitrogen export is mainly in the form of dissolved organic nitrogen. In particular, nitrate is mainly mobilized during stormflow conditions (from 52 % to 80 % of the annual yield). Contrastingly, most of the dissolved organic carbon export occurs during baseflow conditions (from 40 to 70 % of the annual yield). These results point to a decoupling between soil nitrification and nutrient uptake by biota, which brings about the leaking of nitrate to the stream. Hydrochemistry in this Mediterranean intermittent stream is highly variable within and in between years. The antecedent moisture conditions and the magnitude of storm events are key factors on shaping the hydrological responses to storm events. However, storm episodes that occur during similar climatological and hydrological conditions produce different streamwater chemistry depending upon the time of the year. This is so, mainly because of the influence of the summer drought period on streamwater chemistry. Both, the mixing model (EMMA) and the spectral analysis approaches, point out that groundwater is the most important contributor to stormflow in Fuirosos. Nonetheless, the EMMA approach emphasizes how stream water and nitrate sources vary throughout the year. Our results stress the importance of sampling storms during all seasons to draw general conclusions about watershed processes. The mixing model shows that nitrate is retained by biota in the Fuirosos alluvial zone only when streamflow is lower than 80 l/s. Above this threshold, the system is not efficient in retaining nitrate arriving from the catchment. This result might be keep on mind when establishing the importance of near- and in-stream processes for regulating catchment nitrate loads since a major fraction of the annual nitrate export usually occurs during stormflow conditions in many catchments. The spectral analysis also shows that the variability of stream nitrate concentrations is more damped in Fuirosos than in Grimola. This is attributed to the buffer effect that biota has on nitrate concentrations in the Fuirosos alluvial zone, which retards its delivery in relation to the Grimola catchment.
"Efecte de les pluges en la dinàmica del nitrogen en una riera intermitent i mediterrània"

La quantitat de nitrogen dissolt que arriba avui dia als nostres rius i aqüífers és substancialment major a la de fa un parell de dècades a resultes de l'activitat antròpica. Aquest fet ha estimulat força la recerca dels processos relacionats amb el ciclatge del nitrogen, amb la intenció d'esbrinar la capacitat que tenen els ecosistemas terrestres i aquàtics per controlar les càrregues de nitrat que els hi arriben. Alguns d'aquests estudis indiquen que durant les tempestes s'altera de forma substancial la química de l'aigua del riu. Això no obstant, la major part dels treballs realitzats es recolzen en un nombre limitat d'episodis, donada la dificultat inherent al mostreig intensiu de camp a l'hora d'estudiar les respostes hidrològiques i la dinàmica dels soluts durant les crescudes. Tradicionalment, la comunitat científica s'ha dedicat a l'estudi dels processos hidrobiogeoquímics de regions temperades i tropicals, i desafortunadament, les conques Mediterrànies no han estat objecte de la seva atenció. Estudis recents alerten de la fragilitat de les regions Mediterrànies enfront del canvi global, i per tant, urgeixen els estudis focalitzats en aquests ecosistemes.
El principal objectiu d'aquesta tesi ha estat l'estudi de la variabilitat de la dinàmica dels nutrients, en particular del nitrogen, durant les crescudes en relació a la seva dinàmica en condicions de cabal basal en una riera intermitent, Fuirosos, en una conca Mediterrània. La hidrologia i la dinàmica dels soluts a la riera de Fuirosos s'ha comparat amb les de la Grimola, un dels seus efluents més importants. Hi ha diferències litològiques notables entre les dues conques. A més la riera de Fuirosos té zona al.luvial i està flanquejada per un bosc de ribera ben desenvolupat, mentre que la riera de Grimola no té zona al.luvial ni tampoc una zona riberenca ben diferenciada. Per tant, els efectes de (i) la mida de la conca, (ii) la litologia, i (iii) la presència d'una zona al.luvial i riberenca sobre la hidrobiogeoquímica d'un riu, van poder ésser contrastats comparant les rieres de Fuirosos i Grimola. L'estudi es va realitzar al Parc Natural del Montnegre-Corredor al Vallès Oriental entre els anys 1998 i 2004.
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Nhim, Tum. "Variability of intermittent headwater streams in boreal landscape : Influence of different discharge conditions." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-183137.

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Dynamic expansions and contractions of stream networks can play an important role for hydrologic processes as they can connect different parts of the landscape to the stream channels. However, we know little about the temporal and spatial variations of stream networks during different flow and wetness conditions. This study focuses on the contraction and expansion of stream networks during different flow conditions in the boreal Krycklan catchment, located in Northern Sweden. The stream network and initiation points were extracted from a gridded digital elevation model (DEM) of 5-meter resolution, and then compared with the stream network initiation points (heads) observed during the spring flood (freshet) period in 2012. From the results of the study, it was clearly seen that the observed stream heads and the stream heads appearing in the stream network map extracted from DEM did not agree very well. 49% of the total observed stream heads (49) fell onto the low order stream branches and headwater streams derived from the DEM. Only few of them exactly matched the modeled stream heads. Moreover, the modeled stream network was much denser than the observed stream network, and so the simple raster based dynamic model developed could not well represent the dynamic stream network extension in the real system. Most headwater streams in the study catchment were man-made ditches, which were dug to drain water wetlands and to increase forest productivity. The majority of observed stream heads were formed by seepage from the saturated surrounding soils, while only a few of them were formed by saturation overland flow.  On the other hand, the dynamic stream network derived from the DEM suggested that the number of streams of lower order and their lengths was sensitive to change in streamflow, especially during the high flow episode.
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Willard, Eric Hillman Tharsing. "Temperature and relative humidity gradients of intermittent and perennial tributaries in Northern California." [Chico, Calif. : California State University, Chico], 2009. http://hdl.handle.net/10211.4/108.

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Bogan, Michael T. "Hurry up and wait: life cycle and distribution of an intermittent stream specialist (Mesocapnia arizonensis)." UNIV CHICAGO PRESS, 2017. http://hdl.handle.net/10150/626268.

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Species inhabiting intermittent streams must have life-history traits that confer resistance or resilience to flow cessation or drying. However, we lack basic life-history information for most aquatic invertebrate species, especially those from intermittent streams. I documented the life cycle and distribution of an unusual winter stonefly species, Mesocapnia arizonensis (Capniidae). The species was first described from 6 localities in 1969, but its natural history remained enigmatic. I surveyed >90 streams across the southwestern USA, documented the life cycle of M. arizonensis at 1 locality, and experimentally rehydrated dry streambed sediment in search of dormant stoneflies at another locality. Field surveys expanded the number of localities from 22 to 98, most of which were intermittent with flow durations as brief as 3 mo/y, and extended the known range of the species by 800 km. Nymphs were abundant within days of flow resumption, grew rapidly as a single cohort, and started emerging as adults 42 d after flow resumed. The brief appearance of a 2(nd) cohort of tiny nymphs 1 mo before the stream dried indicates direct hatching of at least some eggs. I failed to find dormant stoneflies in the top 30 cm of dry stream sediment, suggesting that M. arizonensis undergoes dormancy deep in the substrate, putting it safely out of reach of scouring summer floods that occur between favorable winter seasons. The remarkable ability of M. arizonensis to survive in short-flow duration streams and to endure multiple consecutive dry years, suggests that the species is well prepared for the drier climatic conditions predicted to occur across its range.
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Bonjour, Sophia. "Influence of Fishes on Macroinvertebrate Communities in Prairie Stream Permanent Water Refugia." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2348.

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Physical factors, such as hydrologic variability, are major structuring forces of prairie stream communities. Macroinvertebrate and algae densities can both decrease sharply in response to floods and drying. Less is known about the influences of biological factors, such as fishes. The influence of fishes on macroinvertebrate communities varies with environmental factors and other biologic interactions, ranging from neutral to strong negative effects on some populations, and the strength of these interactions sometimes appear linked to hydrology. Drying intermittent streams leave permanent water refugia that may be hotspots for interactions between fishes and invertebrates. Effects of fishes on macroinvertebrate communities may vary with invertebrate life cycle stages (e.g., larvae, emerging adults, colonizing adults). I examined macroinvertebrate communities (benthic and emerging) and algal biomass across a range of permanent stream pool sites at Konza Prairie Biological Station with naturally varying densities of fishes. I also manipulated fish densities in a mesocosm experiment to address how fishes may also be effecting colonization during recovery from hydrologic disturbance. Fish biomass had a negative impact on invertebrate abundance, but not biomass or taxa richness, in natural pools. Total fish biomass was not correlated with total insect emergence in natural pools, but orangethroat darter (Etheostoma spectabile) biomass was inversely correlated with emerging Chironomidae biomass (r2 = 0.43, p = 0.047) and individual midge body size (r2 = 0.61, p = 0.014). Predatory fish biomass and a date interaction appeared in top linear models, indicating fish may also delay insect emergence from natural pools. Fish presence reduced abundance of colonizing insects (p < 0.001) and total invertebrate biomass (p = 0.001) in mesocosms. Mesocosm insect communities in pools without fishes were characterized by more Chironomidae, Culicidae, and Corduliidae (p < 0.001 for all). Chlorophyll-a increased between sampling dates in mesocosms, but did not differ between treatments. Not all life stages showed the same response to fishes, illustrating the need for understanding life histories in order to interpret the influence of fishes. Understanding how fishes in prairie streams affect ecosystem structure and function is critical for conservation and management of remaining grassland streams. Results suggest fishes can influence colonization and community structure in prairie stream pools, which serve as important refugia during hydrologic disturbance and source areas for colonists during recovery.
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Taylor, Ritchie Don. "Water Quality Aspects of an Intermittent Stream and Backwaters in an Urban North Texas Watershed." Thesis, University of North Texas, 2002. https://digital.library.unt.edu/ark:/67531/metadc3206/.

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Pecan Creek flows southeast through the City of Denton, Texas. Characterized as an urban watershed, the basin covers approximately 63.5 km2. Pecan Creek is an intermittent stream that receives nonpoint runoff from urban landuses, and the City of Denton's wastewater treatment plant, Pecan Creek Water Reclamation Plant, discharges effluent to the stream. Downstream from the City of Denton and the wastewater treatment plant, Pecan Creek flows about 6,000 m through agricultural, pasture, and forested landscapes into Copas Cove of Lake Lewisville, creating backwater conditions. Pecan Creek water quality and chemistry were monitored from August 1997 to October 2001. Water quality was influenced by seasonal, spatial, climatic, and diurnal dynamics. Wastewater effluent discharged from the Pecan Creek Water Reclamation Plant had the greatest influence on water quality of the stream and backwaters. Water quality monitoring of Pecan Creek demonstrated that dissolved oxygen standards for the protection of aquatic life were being achieved. Water quality modeling of Pecan Creek was completed to assess future increases in effluent flow from the Pecan Creek Water Reclamation Plant. Water quality modeling indicated that dissolved oxygen standards would not be achieved at the future effluent flow of 21 MGD and at NPDES permitted loadings. Model results with application of a safety factor indicated that the maximum allowable concentrations for a 21 MGD discharge would be 2.3 mg/L of ammonia and 7.0 mg/L of biochemical oxygen demand at summer conditions. Drought conditions that occurred from 1998 to 2001 reduced water levels in Lake Lewisville and impacted dissolved oxygen water quality in Pecan Creek. Water quality observations made during the period of drought allowed for the development of a model to estimate the zone of the dissolved oxygen sag in Pecan Creek based on reservoir elevation. Finally, monitoring results were analyzed with nonparametric statistical procedures to detect water quality changes in the backwater area of Pecan Creek, as influenced by storm events.
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Belli, Joseph P. "Movements, habitat use, and demography of Western Pond Turtles in an intermittent central California stream." Thesis, San Jose State University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10011666.

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Western Pond Turtles, Emys (Actinemys) marmorata, were captured (n=173) in 2011 (wet year) and 2012–2013 (successively drier drought years) along upper Coyote Creek, an intermittent stream in central California. Males outnumbered females 2.8:1, juveniles less than 120 mm long made up 26% of captures, growth rates varied among individuals, and little growth occurred in turtles older than 10 years. I radio-tracked turtles from May 2011 through August 2013 to ascertain movements and seasonal habitat use. Males had much larger home ranges than females (means of 2281 m for males and 501 m for females in 2012), and males moved extensively in April and May, during the apparent breeding season. Turtles preferred deep and complex pools, complex runs, and backwaters. Turtles left the stream for upland habitats in late spring and summer as stream flow ceased and pool connectivity was broken. There was substantial variation in departure dates among individuals and between wetter and drier reaches. Mean departure date was 16 August in 2011, but decreased to 20 July in 2012 and 28 June in 2013, as the drought intensified. Upland sites were mostly within 100 m of the stream, beneath dried leaves and/or thatch, and on slopes varying from flat to over 40%. Turtles remained upland for almost seven months in 2011–2012, although there was much variation. Mean return to stream dates were 27 February (males) and 16 March (females).

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Rutledge, Charles Jerry 1941. "Physiological Ecology, Population Genetic Responses and Assemblage Stability of Fishes in Two Southwestern Intermittent Stream Systems." Thesis, University of North Texas, 1991. https://digital.library.unt.edu/ark:/67531/metadc277808/.

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Six sites within the Denton and Hickory Creek watersheds were sampled over three years to assess the impact of seasonal intermittent stream conditions on the ichthyofauna. An integrated approach using field and laboratory techniques was employed to evaluate the responses of the fishes.
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Chapman, Lauren J. (Lauren Jeanette). "Population ecology of the fish Poecilia gillii in an intermittent tropical stream : the effects of seasonal flooding." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74330.

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This thesis demonstrates how the intermittent nature of seasonal tropical fresh waters facilitates and impedes the dispersal of fish and how the variability among residual dry season pools affects the dynamics of isolated populations. I focused on the seasonal ecology of Poecilia gillii from pools in a steep gradient, intermittent stream in Costa Rica. Water temperature and dissolved oxygen concentration were affected by season, by between-pool differences, and by the interaction between seasonal and spatial influences. Seasonal flooding resulted in a catastrophic loss of fish from most pools. Population loss was influenced by the susceptibility of the pools to flooding and population density, with mortality occurring primarily in nearby desiccating "graveyard" pools. Pools increased in population size and density over the 5-month post-flood study period, and their densities converged to their pre-flood values. Variability in the rate of increase among pools was related to water quality and population density. Striking changes in the size and abundance of males over the season suggest social influences on maturation in Poecilia gillii.
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Lubbers, Hannah R. "Impacts of Urbanization and Flow Permanence on Headwater Stream Macroinvertebrates (Hamilton County, Ohio)." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1243026143.

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Books on the topic "Intermittent Stream"

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Vance, Linda K. Geographically isolated wetlands and intermittent/ephemeral streams in Montana: Extent, distribution, and function. Helena, Mont: Montana Natural Heritage Program, 2009.

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Vance, Linda K. Geographically isolated wetlands and intermittent/ephemeral streams in Montana: Extent, distribution, and function. Helena, Mont: Montana Natural Heritage Program, 2009.

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DeLong, Lewis L. Estimating average dissolved-solids yield from basins drained by ephemeral and intermittent streams, Green River basin, Wyoming. Cheyenne, Wyo: Dept. of the Interior, U.S. Geological Survey, 1988.

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V, Zale Alexander, ed. The Physicochemistry, flora, and fauna of intermittent prairie streams: A review of the literature. Washington, D.C: U.S. Dept. of the Interior, Fish and Wildlife Service, Research and Development, 1989.

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Lee, Yu Man. Amphibian communities and physical characteristics of intermittent streams in old-growth and young forest stands in western Oregon. 1997.

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Intermittent Rivers and Ephemeral Streams. Elsevier, 2017. http://dx.doi.org/10.1016/c2015-0-00459-2.

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Vance, Linda K. Literature review: Hydrology-ecology relationships in Montana Prairie wetlands and intermittent/ephemeral streams. 2013.

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Kiss, Thomas, and Paolo Pelosi. Lung recruitment techniques in the ICU. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199600830.003.0120.

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Lung recruitment manoeuvres (RMs) have been suggested as a means of homogenizing the lung structure and distribution of the mechanical stress across the lungs. Such effects can be achieved provided enough pressure is applied for enough time at the airways, and maintained if adequate levels of positive end-expiratory pressure (PEEP) are used. When RMs effectively open atelectatic tissue, shear stress, and cyclic collapse/reopening are importantly reduced. The lung response to RMs is mainly determined by cause and severity of lung injury, and the position of the lungs with respect to the gravity gradient. RMs can be performed in several different ways, the most relevant RMs in terms of clinical applicability are sustained inflation manoeuvres, high pressure controlled ventilation, incremental PEEP, and intermittent sighs.
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Cohen, Jeffrey A., Justin J. Mowchun, Victoria H. Lawson, and Nathaniel M. Robbins. A 19-Year-Old Male with Stiffness and Weakness After Waking. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780190491901.003.0026.

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The distinctive, but somewhat odd, development of intermittent “attacks” of weakness/stiffness define this disorder. Interview of the patient to determine the impact of diet (including timing, content and relationship of attack to fasting), activity, emotional stress, alcohol intake, cold exposure, time of day and physiologic perturbations (eg – electrolytes, infection, dehydration, etc) help to confirm and categorize the periodic paralysis. Periodic paralyses are most often associated with a genetic channelopathy. However, they can also occur as a result of a secondary causes including thyroid disturbance or distal renal tubular acidosis. The clinical picture, laboratory investigation, and treatment of this condition are presented.
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Book chapters on the topic "Intermittent Stream"

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del Campo, Rubén, Arnaud Foulquier, Gabriel Singer, and Thibault Datry. "Plant Litter Decomposition in Intermittent Rivers and Ephemeral Streams." In The Ecology of Plant Litter Decomposition in Stream Ecosystems, 73–100. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-72854-0_5.

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Mas-Martí, Esther, Emili García-Berthou, Sergi Sabater, Sylvie Tomanova, and Isabel Muñoz. "Comparing fish assemblages and trophic ecology of permanent and intermittent reaches in a Mediterranean stream." In Global Change and River Ecosystems—Implications for Structure, Function and Ecosystem Services, 167–80. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-94-007-0608-8_12.

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Hanczewski, Sławomir, and Maciej Stasiak. "Point-to-Group Blocking in 3-Stage Switching Networks with Multicast Traffic Streams." In Service Assurance with Partial and Intermittent Resources, 219–30. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-540-27767-5_22.

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Haw, R. C., J. K. Foss, and J. F. Foss. "Vorticity Based Intermittency Measurements in a Single Stream Shear Layer." In Advances in Turbulence 2, 90–95. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-83822-4_15.

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Stanlake, G. J., and A. J. Landwer. "Rapid bioassessment of intermittent streams in the Upper Brazos River watershed." In Global Environmental Biotechnology, 559–65. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-017-1711-3_48.

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Navarrete-Opazo, A., E. A. Dale, and Gordon S. Mitchell. "Therapeutic Potential of Intermittent Hypoxia: Lessons from Respiratory Motor Plasticity." In Translational Research in Environmental and Occupational Stress, 31–42. New Delhi: Springer India, 2014. http://dx.doi.org/10.1007/978-81-322-1928-6_4.

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Serebrovskaya, T. V. "Lessons from a 20-Year Investigation of Intermittent Hypoxia: Principles and Practices." In Translational Research in Environmental and Occupational Stress, 267–74. New Delhi: Springer India, 2014. http://dx.doi.org/10.1007/978-81-322-1928-6_22.

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Pischik, Elena, and Raili Kauppinen. "Potential Role of Oxidative Damage in Neurological Manifestations of Acute Intermittent Porphyria." In Oxidative Stress and Free Radical Damage in Neurology, 293–311. Totowa, NJ: Humana Press, 2010. http://dx.doi.org/10.1007/978-1-60327-514-9_16.

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Tung, Nguyen Thanh, and Dmitry Sboev. "Transitional Intermittency in a Flat Plate Boundary Layer Subjected to Elevated Free-Stream Turbulence." In IUTAM Laminar-Turbulent Transition, 233–41. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-67902-6_20.

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Hodda, Mike, and Walter Traunspurger. "Nematodes from extreme and unusual freshwater habitats." In Ecology of freshwater nematodes, 109–50. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789243635.0004.

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Abstract This chapter discusses the ecology and biogeography of nematodes from freshwater environments that are extreme in temperature, chemical composition, variability, or isolation. Described and compared are the compositions of nematode faunas from hot or mineral springs, pools and bogs in polar regions, intermittent lakes or pools or streams, freshwater pools in bromeliads or tree hollows, stemflow, fresh groundwaters, and caves. Comparisons of the nematode faunas from these extreme habitats with those from more typical freshwater environments are also provided. Also discussed are nematodes with evolutionary affinities to freshwaters that are found in estuarine sediments along with nematodes from freshwaters with evolutionary affinities to otherwise marine taxa. The emphasis is on broad ecological patterns rather than on detailed species interactions with the various freshwater environments. Thus, the chapter focuses on genera or higher taxa rather than species.
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Conference papers on the topic "Intermittent Stream"

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Kalfas, Anestis I., and Robin L. Elder. "Effects of Free Stream Turbulence on Intermittent Boundary Layer Flows." In ASME 1995 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1995. http://dx.doi.org/10.1115/95-gt-124.

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This paper considers the effects of free stream turbulence intensity on intermittent boundary layer flows related to turbomachinery. The present experimental investigation has been undertaken under free stream flow conditions dominated by grid generated turbulence and Reynolds numbers appropriate for turbomachinery applications. Unseparated flow transition in the boundary layer has been considered using a flat plate with the C4 leading edge which has been designed to avoid laminar separation. This configuration provided the opportunity to study the effect of a realistic turbomachinery leading edge shape on transition. Boundary layer type hot-wire probes have been used in order to acquire detailed information about the effect of the free stream conditions and the leading edge configuration on the structure of the boundary layer. Furthermore, information about the intermittency distribution throughout the boundary layer has been obtained using statistical analysis of the velocity record of the flow field.
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Badrzadeh, Honey, Ranjan Sarukkalige, and Jayawardena A. W. "Combined Wavelet-Neural Network Model for Intermittent Stream Flow Prediction." In Research, Development and Practice in Structural Engineering and Construction. Singapore: Research Publishing Services, 2012. http://dx.doi.org/10.3850/978-981-08-7920-4_aw-9-0443.

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Ninov, Plamen, and Tzviatka Karagiozova. "MONITORING AND INVESTIGATION OF INTERMITTENT RIVERS IN BULGARIA." In XXVII Conference of the Danubian Countries on Hydrological Forecasting and Hydrological Bases of Water Management. Nika-Tsentr, 2020. http://dx.doi.org/10.15407/uhmi.conference.01.01.

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River flows could be defined according to their surface hydrologic stream duration as either perennial or temporary. Normally perennial streams flow throughout the year, while temporary streams lack surface flow for some periods of the year. Temporary streams are classified as intermittent or ephemeral. Intermittent streams flow in some periods as result of snowmelt and eventually elevated groundwater tables during the periods of increased precipitations. Intermittent streams are poorly represented in existing river monitoring programs in Bulgaria and seldom are objects of regular monitoring. Only in several gauging stations exist hydrological time series. Furthermore, intermittent and ephemeral streams are not adequately protected by current legislation and management strategies in Bulgaria and generally are neglected. The authors discuss the climatic, hydrological and soil conditions in different part of the country as the major factors determining their origin and distribution. Covering the whole territory of Bulgaria the authors identify four main types of intermittent streams as: 1) intermittent flows as result of Mediterranean climatic impact located in the southern part of the country; 2) sinking intermittent flows as result of specific geological and soil characteristics, 3) intermittent flows in large karst and loess areas and finally 4) the sinking flows in alluvium depositions mainly along the large mainstreams. Nevertheless, the limited number of gauging stations built up at these rivers some hydrological information is collected and statistical results are presented as duration curves of temporal rivers, hydrographs with seasonal characteristics etc. Intermittent streams have a hydrologic flow regime with very specific characteristics that place them as interact between land and water. Unfortunately, in Bulgaria there are poorly mapped, recognized, and protected but they have a critical influence on the ecological health of networks. There exists a strong need for new approaches to scientifically study, the structure and function of temporal streams. The construction of monitoring network for the regular registration of their hydrological regime is surely the first required step for their future detailed ingestions, use and protection.
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Vicedo, J., S. Vilmin, W. N. Dawes, and A. M. Savill. "Intermittency Transport Modeling of Separated Flow Transition." In ASME Turbo Expo 2003, collocated with the 2003 International Joint Power Generation Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/gt2003-38719.

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An intermittency transport model is proposed for modeling separated-flow transition. The model is based on earlier work on prediction of attached flow bypass transition and is applied for the first time to model transition in a separation bubble at various degrees of free-stream turbulence. The model has been developed so that it takes into account the entrainment of the surrounding fluid. Experimental investigations suggest that it is this phenomena which ultimately determines the extent of the separation bubble. Transition onset is determined via a boundary layer correlation based on momentum thickness at the point of separation. The intermittent flow characteristic of the transition process is modeled via an intermittency transport equation. This accounts for both normal and streamwise variation of intermittency and hence models the entrainment of surrounding flow in a more accurate manner than alternative prescribed intermittency models. The model has been validated against the well established T3L semicircular leading edge flat plate test case for three different degrees of free-stream turbulence characteristic of turbomachinery blade applications.
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Yavuzkurt, Savash. "Effects of Free Stream Turbulence on the Instantaneous Heat Transfer in a Wall Jet Flow." In ASME 1995 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1995. http://dx.doi.org/10.1115/95-gt-043.

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This is a preliminary study in order to understand how free stream turbulence increases the heat transfer. Effects of free stream turbulence on the instantaneous heat transfer were investigated in a wall jet flow. Heat transfer traces obtained by a hot film probe flush-mounted with the surface showed an intermittent structure with definite peaks at certain time intervals. Number of peaks per unit time increased with increasing turbulence intensity. A wall jet test rig was designed and built. The initial thickness and the velocity of the wall jet were 10 cm and 24.4 m/s respectively. The hot film probe which was flush with the surfaces was positioned at 10 cm intervals on the surface in the flow direction. The profiles of mean velocity and axial component of the Reynolds stress were measured with a horizontal hot wire probe. Space correlation coefficients for u′ and q′ were obtained in the vertical direction to the wall. This paper concentrates on the effects of turbulence level on the instantaneous heat transfer at the wall. It is speculated that intermittent structure of the heat transfer traces are related to burst phenomena and increase in heat transfer is due to increased ejections (bursts) at the wall with increasing turbulence levels.
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Simoes, Sara, Ana Lúcia Gonçalves, Inês Rodrigues, Cristina Canhoto, and Aingeru Martínez. "Leaf litter decomposition in an intermittent stream: channel <em>vs</em>. riparian area." In 5th International Electronic Conference on Water Sciences. Basel, Switzerland: MDPI, 2020. http://dx.doi.org/10.3390/ecws-5-08043.

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Volino, Ralph J. "An Investigation of the Scales in Transitional Boundary Layers Under High Free-Stream Turbulence Conditions." In ASME Turbo Expo 2002: Power for Land, Sea, and Air. ASMEDC, 2002. http://dx.doi.org/10.1115/gt2002-30233.

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The scales in a transitional boundary layer subject to high (initially 8%) free-stream turbulence and strong acceleration (K as high as 9×10−6) have been investigated using wavelet spectral analysis and conditional sampling of experimental data. The boundary layer shows considerable evolution through transition, with a general shift from the lower frequencies induced by the free-stream unsteadiness to higher frequencies associated with near wall generated turbulence. Within the non-turbulent zone of the intermittent flow, there is considerable self-similarity in the spectra from the beginning of transition to the end, with the dominant frequencies in the boundary layer remaining constant at about the dominant frequency of the free-stream. The frequencies of the energy containing scales in the turbulent zone change with streamwise location and are significantly higher than in the non-turbulent zone. When normalized on the local viscous length scale and velocity, however, the turbulent zone spectra also show good self-similarity throughout transition. Turbulence dissipation occurs almost exclusively in the turbulent zone. The velocity fluctuations associated with dissipation are isotropic, and their normalized spectra at upstream and downstream stations are nearly identical. The distinct differences between the turbulent and non-turbulent zones suggest the potential utility of intermittency based transition models in which these zones are treated separately. The self-similarity noted in both energy containing and dissipation scales in both zones suggests possibilities for simplifying the modeling for each zone.
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Borowski, Walter S., Jonathan M. Malzone, James S. Winter, Ryan M. Penn, and Reid E. Buskirk. "QUANTIFYING NUTRIENT EXPORT FROM AN UPLAND, INTERMITTENT STREAM DRAINING A WORKING FARM, MADISON COUNTY, KENTUCKY: PRELUDE TO NUTRIENT MITIGATION." In GSA Annual Meeting in Indianapolis, Indiana, USA - 2018. Geological Society of America, 2018. http://dx.doi.org/10.1130/abs/2018am-319776.

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Suzen, Y. B., and P. G. Huang. "Numerical Simulation of Unsteady Wake/Blade Interactions in Low Pressure Turbine Flows Using an Intermittency Transport Equation." In ASME Turbo Expo 2004: Power for Land, Sea, and Air. ASMEDC, 2004. http://dx.doi.org/10.1115/gt2004-53630.

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An extensive computational investigation of the effects of unsteady wake/blade interactions on transition and separation in low-pressure turbines has been performed by numerical simulations of two recent sets of experiments using an intermittency transport equation. The experiments considered have been performed by Kaszeta and Simon [1] (Kaszeta et al. [2,3]), and Stieger [4] (Stieger and Hodson [5]) in order to investigate the effects of periodically passing wakes on laminar-to-turbulent transition and separation in low-pressure turbines. The test sections were designed to simulate unsteady wakes in turbine engines for studying their effects on boundary layers and separated flow regions over the suction surface. The numerical simulations of the unsteady wake/blade interaction experiments have been performed using an intermittency transport model. The intermittent behavior of the transitional flows is taken into account and incorporated into computations by modifying the eddy viscosity, with the intermittency factor. Turbulent quantities are predicted by using Menter’s two-equation turbulence model (SST). The intermittency factor is obtained from the transport equation model which can produce both the experimentally observed streamwise variation of intermittency and a realistic profile in the cross stream direction. Computational results are compared to the experiments. Overall, general trends are captured and prediction capabilities of the intermittency transport model for simulations of unsteady wake/blade interaction flowfields are demonstrated.
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Volino, Ralph J. "Wavelet Analysis of Transitional Flow Data Under High Free-Stream Turbulence Conditions." In ASME 1998 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/98-gt-289.

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Transitional flow data from boundary layers subject to strong acceleration (K as high as 9×10−6) and high free-stream turbulence (∼8%) were analyzed using wavelet transforms. Wavelet analysis provides the energy content of a signal on both a frequency and instantaneous time basis. It differs from traditional Fourier spectral analysis, which can only provide the spectral energy on a time averaged basis. Instantaneous velocity data from intermittent, transitional boundary layers were segregated into turbulent and non-turbulent zones through conditional sampling. Wavelet analysis was used to determine the frequency content of the velocity fluctuations and turbulent shear stress in the two zones separately. The streamwise velocity fluctuations in the turbulent and non-turbulent zones appeared similar. This was attributed to the effect of the free-stream turbulence, which had the same effects on both zones. The wall-normal fluctuations and turbulent shear stress were of significantly higher magnitude and frequency in the turbulent zone. These results suggest that turbulence models should be based on transport quantities rather than turbulent kinetic energy. The regions just upstream and just downstream of turbulent zones were also analyzed, to check for possible important frequencies leading to the initiation of turbulence or characteristic of the “calm” zone trailing a turbulent spot. No distinct behavior was observed in either of these zones. Uncertainty values associated with the wavelet spectra are high due to the short data records available. Results are shown to be valid in spite of these uncertainties, however longer data records should be acquired in future studies.
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Reports on the topic "Intermittent Stream"

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Carpenter, Forrest. Understanding the Importance of Intermittently Fragmented Stream Habitat for Isolated Westslope Cutthroat Trout (Oncorhynchus clarki lewisi) in the Colville National Forest, Washington. Portland State University Library, January 2000. http://dx.doi.org/10.15760/etd.3295.

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Estimating average dissolved-solids yield from basins drained by ephemeral and intermittent streams, Green River basin, Wyoming. US Geological Survey, 1988. http://dx.doi.org/10.3133/wri874222.

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