ISSN:0886-9375    

DOI:10.1002/rrr.3450070102

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractThe history of groundwater ecological research carried out during the last 75 years along the Rhǒne, Rhine and Danube alluvial plain is reviewed. Phreatobiology, a concept introduced by Motas (1958), is denned, and the main phases in the development of this research direction dealing with the study of groundwater organisms living in the unconsolidated sediments are reviewed.During a preecological phase of phreatobiology, students were interested mainly in the discovery of exciting groundwater organisms and the explanation of their origin. Modern groundwater ecological research began with Schwoerbel's investigations of the Upper Danube alluvial sediments in the beginning of the 1960s. Progress in phreatobiological research was made during the last twenty years through the description of the complex mosaic of habitats in the Rhǒne and Danube plains by French and Austrian students, by applied and theoretical research carried out on the Upper Rhine by S. Husmann.Three main directions of modern groundwater ecological research are discussed in detail: the ecotone approach developed by students of the University of Lyon on the Rhǒne; the ‘minimalist’ approach, the study of a reduced groundwater ecosystem in the wetland area of the Danube, near Vienna, carried out by an interdisciplinary team; and finally, the ecotoxicological approach developed by Dutch scientists working on the lower Rhine plain. Modern ecological research has inspired groundwater ecology with new concepts and ideas, so that phreatobiology has today expanded into a progressive field of research which complements the other two limnological subject areas, the study of lentic and lotic surface

ISSN:0886-9375    

DOI:10.1002/rrr.3450070103

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractThe ‘hyporheic zone’ is described. According to the classical definition, water below the sediment surface is groundwater and the hyporheic interstitial zone is part of the phreatic system. This ignores the vertical distribution of the epigeic benthic fauna. The uppermost layer of the sediment (bed sediments) of the hyporheic zone is dominated by epigeic faunal elements and is therefore part of the surface system. In contrast to hypogeic species, the depth penetration of epigeic species is limited. Possible explanations are discus

ISSN:0886-9375    

DOI:10.1002/rrr.3450070104

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractThe interstitial assemblages of the River Rhine were studied in the Rhinau sector (France). The studied area is located in aVegulated channel of the river, controlled by a hydroelectric dam. Twenty stations were sampled in September 1988. Ten litres of interstitial water were pumped at 50 cm depth in each station using the Bou‐Rouch technique. Interstitial waters were poorly oxygenated and the hyporheic fauna had three major characteristics: (1) microcrustaceans were dominant, (2) the insects were rare and (3) the stygofauna was absent. The richest stations were well oxygenated and did not correspond to any particular geomorphological features. These findings contrast with the situation observed on other large European rivers (Rhǒne, Danube) where the interstitial assemblages appear to be locally more diversified and rich in stygofau

ISSN:0886-9375    

DOI:10.1002/rrr.3450070105

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractWe observed the dynamic changes in the hyporheic zone, both in the vertical (0‐80 cm) and horizontal directions. Two stations with different hydrological conditions were compared, and subsequently related to two basic processes: infiltration of surface water into the sediments of the river bottom and repeated entry back to the surface stream. By comparing these two locations we attempted to show the existence of a continuous exchange of water between the surface of the river and the hyporheic zone in a process which we call ‘small bottom circulation’. At the same time, we also attempted to demonstrate that this process involves the self‐purification of the infiltrated water. We presume that self‐purification is realized both by means of physical processes (filtration, sedimentation and deposition) and by the biological decomposition of organic matter. Self‐purification of the infiltrated water between the stations which were compared are proved, above all, by the values of O2, BOD, COD, FPOM + CPOM, pH and conductivity. There are also remarkable differences in the qualitative composition in the macroinvertebrat

ISSN:0886-9375    

DOI:10.1002/rrr.3450070106

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractRelationships between invertebrates, substrate characteristics and trophic factors were investigated, with special emphasis on the hyporheic habitat, in order to characterize the functioning of different running waters ecosystems.Three contrasting study sites were chosen in catchments exhibiting different features: (1) a meandering reach of the Loire River in its alluvial floodplain, upstream of the ‘Bec d'Allier’; (2) a reach of the Galaure with a fairly developed riparian corridor, a small sinuous foothill river; and (3) a braided reach of the Drac, an alpine torrential stream.Each site was sampled once using the freezing‐core technique with previous electro‐positioning of the invertebrates. In each site, four 60 cm cores were extracted, each one from different morphodynamic units.In the Loire and Galaure rivers, most invertebrates are found in the first 15 cm of the sediment, with the exception of some particular taxa or morphodynamic units (riffle head). Conversely, in the Drac lotic units, maximum density of invertebrates occurs between 15 and 30 cm and more than 75 per cent of all organisms are found at a depth>15 cm. The vertical distribution of organisms does not follow a uniform pattern in different streams.In the substrate, the vertical distribution of macroinvertebrates is very closely related to porosity in contrast with trophic parameters that always decrease with depth. The porosity is negatively correlated with the percentage of sand in the sediment and seems to be important in determining the vertical distribution of fauna, and should be integrated in a functional typology of running waters.The trophic parameters and the structure of invertebrate community with its dominant feeding groups allow discrimination of the differen

ISSN:0886-9375    

DOI:10.1002/rrr.3450070107

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractThe harpacticoid copepodLimnocamptus echinatus(Mrazek) shows a very distinct large‐scale vertical distribution within the bed sediments of Oberer Seebach, a second‐order gravel stream. The population peak appears in a sediment layer between 15 and 35 cm over long periods on average. Abundances are significantly lower in the topmost sediments and sediment layers below 50 cm depth. The large‐scale vertical distribution is mainly influenced by the changes and pattern of temperature and discharge, which influences the current velocity of the surface and interstitial water. Effects appear quite different, when permanent flooded areas and areas that periodically fall dry on the surface are compared.Limnocamptus echinatusis forced deeper into the sediments of the gravel bar during low water temperatures and/or high discharge situations. On permanent flooded areas the vertical distribution is more stable over long periods, but higher fluctuations occur during short periods. TheLimnocamptus echinatuspopulation shows higher mobility in deeper sediment layers (40 to 60 cm sediment depth). Comparing longer periods, water flow and the transport of fine material differ in deeper sediment layers. The water current is much slower, producing a tendency for fine material sedimentation. This might be the main reason for the higher mobility in deeper sediment layers and the restriction of 90 per cent of theLimnocamptus echinatuspopulation to a sediment depth of 50 cm. High mobility in vertical and horizontal directions within the bed sediments is interpreted as normal reactions and adaptations to the dynamic behaviour of the system, mainly forced by physical parameters. Biological parameters appear as subdominant for large‐scale vertical distri

ISSN:0886-9375    

DOI:10.1002/rrr.3450070108

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractThe paper focuses on the definition of the vulnerability of phreatic waters to surface water pollution. The amplification of water exchanges between surface and underground waters, because of human activities, is considered as a risk of contamination of aquifers. The aim of this paper is to present a first synthesis of oligochaetes as biological describers of these exchanges.Field investigations have shown that several rare and/or stygophilous taxa are found in surface (coarse) sediments of rivers upstream and/or downstream of dams or gravel operations. These observations relate to species such asPropappus volki, Pristinaspp.,Chaetogaster parvus, Rhyacodrilus carsticus, R. falciformis, Phallodrilusspp. The data suggest that these species invade surface waters from phreatic or interstitial waters when water flows are amplified between the two. Flow amplification is considered as a consequence of dams' and gravel operations' hydraulic impact. But the lack of hydraulic validation of the presumed active exchanges describer's (AED) ecological status given to those species remains a problem, giving the opportunity to examine the link between hydraulics and biology.Preliminary results on two gravel pits of La Wantzenau (Rhine alluvial valley, France) have shown relations between the distribution of oligochaetes, especially Lumbriculidae, and soil filtration properties. Two other studies were planned along an industrially polluted tract of the River Rhǒne (Grand Gravier Island). Horizontal and vertical zonation of the river banks were performed by studying simultaneously hydraulics and oligochaetes. Preliminary results have shown that the absolute and relative abundances of taxa such asPhallodrilussp. andS. velutinusincrease in relation to the permeability of superficial coarse substrate in the horizontal plane, and to the current velocity in underground porous media in the vertical plane. The increasing percentages ofP. barbatusand the decreasing percentages of Tubificidae reveal active exchange zones where superficial waters are renewed by groundwaters. Some other species such asP. vejdovskyiseem to be potential describers of water exchanges

ISSN:0886-9375    

DOI:10.1002/rrr.3450070109

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractInterstitial invertebrate assemblages of the Rhǒne River were studied at the scale of the entire alluvial plain. Ten stations, located in five former channels, were sampled with a Bou‐Rouch pump at 50 and 100 cm depth. The chemical characteristics of the interstitial water allowed the differentiation of stations without hydrological connections with the subterranean habitats, stations fed by surface water coming through the bank sediments and stations fed by true groundwater. The faunal assemblages reflect the difference between connected and isolated stations but did not demonstrate any differences related to the origin of the water. In fact the interstitial assemblages are distributed along a gradient from the margin of the floodplain (stations with a high physical stability associated with the absence of flood periods) to the area close to the main channel regularly influenced by floods. These results demonstrate that both groundwater characteristics and the position of the station in the floodplain influence the spatial distribution of interstitial fauna in the alluvial valley of the Rhǒne Ri

ISSN:0886-9375    

DOI:10.1002/rrr.3450070110

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractArtificial substrates buried in stream sediments at the karst/floodplain interface were used to examine the spatial and temporal variations ofNipharguspopulations. The study was carried out at two stations in two different areas of the French Jura. One was mainly supplied by karst water (Verna station), the other by both karst and surface waters (Pissoir station). The occupation of interstitial habitat was found to depend on several interacting factors:1The waterflow and its changes at the outlet. The correlation between abundance of individuals and discharge was strongest with the discharges two to four days before sampling. The structure and restoration of populations after a spate related to geological characteristics. In particular, restoration was slower and more difficult in the sediments located at the base‐level of a massif (Verna) than at an overflow level (Pissoir).2The location of the sediments. At the Pissoir station, the number of individuals was higher at the main outflow, but also for both stations, on the banks opposite the outlet. Animals drifting from the karst system found refuge in the sediment of the opposite bank. Almost noNipharguswere found upstream from the outlets. At the Verna station,Nipharguswere only found inside the cave.3The variability of the number of animals at different depths in the sediment was more difficult to explain. At the station mainly supplied by karst water, which presented a relatively constant flow during the study, the distribution seemed to be random. At the other station, where discharge varied considerably, the vertical distribution globally presented a gradient in abundance with more individuals in the upper sediment level. This gradient varied according to the samples. Discharge changes partly explained these result

ISSN:0886-9375    

DOI:10.1002/rrr.3450070111

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY