Description: Das Projekt "Stream network expansion and contraction - patterns, controls and importance (STREAMEC)" wird/wurde gefördert durch: Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung. Es wird/wurde ausgeführt durch: Universität Zürich, Geographisches Institut.Temporary streams are very common, also in humid climates, and often represent a substantial portion of total stream length. However, temporary streams are generally not included in stream monitoring networks and hydrologists have, so far, largely ignored them. As a result, little is known about the hydrological responses of temporary streams and the factors that control the occurrence of flow in temporary streams. Connectivity of previously disconnected stream segments can result in sudden increases in streamflow and significantly alter stream water quality in downstream perennial streams. For the latter, it is especially important to note that organic material and other substances that might have accumulated in the channel during periods of no flow, might be flushed out at the onset of flow in temporary streams, causing a water chemistry dynamic that is different from that of constantly flowing streams. It is thus important to study how and when connectivity between flowing sections of the temporary stream network is established and what controls the occurrence of flow in temporary streams. The overall aim of the proposed research is to explore these aqua temporaria incognita. This will provide a better understanding of temporary streams and their importance for spatial and temporal variations in runoff and stream water quality in headwater catchments. This will be done by detailed field experiments in two pre-Alpine headwater catchments. We will map the presence of flowing water in temporary streams using an array of low costs sensors, time-lapse cameras and traditional mapping techniques to study how connectivity of flowing stream reaches is established and what topographic and landscape factors control the occurrence of flow seasonally and during different events. We will use the occurrence of flow in the stream network as an indicator of subsurface flow and hillslope-stream connectivity in order to better understand the precipitation and groundwater level thresholds that control runoff generation. This is a novel way to obtain information on the spatial variability of the temporal controls on subsurface flow generation. Finally, by monitoring the onset of flow and connectivity of stream reaches and simultaneous sampling of water chemistry in temporary streams during events, we will determine how connectivity of the temporary stream network affects downstream water quality.
SupportProgram
Origin: /Bund/UBA/UFORDAT
Tags: Gebirgsbach ? Bach ? Hydrodynamik ? Vegetation ? Wasserstraße ? Fluss ? Fließgewässer ? Kartierung ? Messstellennetz ? Sensor ? Flusswasser ? Geoinformation ? Abfluss ? Gewässerüberwachung ? Kartographie ? Regenwasser ? Organisches Material ? Topographie ? Karte ? Grundwassernutzung ? Wasserspeicher ? Monitoring ? Niedrigwasser ? Studie ? Geologie ? Einzugsgebiet ? Wasserströmung ? Wasserqualität ? Grundwasserstand ? Untergrund ? Humides Klima ? Forschung ? Niederschlag ? Freilandversuch ? Schwellenwert ? Stoffstrom ? Landschaft ? Hydrologie ? channel network ? spatial patterns ? Abflussmenge ? temporary streams ? connectivity ? headwater catchment ? runoff generation ?
License: cc-by-nc-nd/4.0
Language: Englisch/English
Time ranges: 2015-11-01 - 2018-11-30
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