The impact of deposited fine sediment on benthic macroinvertebrates in small headwater streams in Luxembourg ; Die Auswirkung von Feinsedimentablagerung auf benthische Wirbellose in luxemburgischen Mittelgebirgsquellbächen
Intensive agriculture causes increased soil erosion worldwide, resulting in a higher level of fine sediment in aquatic systems. Although the accumulation of fine sediment (incorganic and organic particles) on the streambed is a widely-known phenomenon in streams and rivers, no comprehensive field studies have been conducted on the effect of deposited fine sediment on the benthic macroinvertebrates in small headwater streams in Central Europe. This thesis’ current questions are, firstly, which environmental variables influence the input and the deposition of fine sediment and, secondly, does th... Mehr ...
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Dokumenttyp: | dissertation |
Erscheinungsdatum: | 2013 |
Schlagwörter: | ddc:570 / ddc:57 / Fakultät für Biologie » Aquatische Ökologie |
Sprache: | Englisch |
Permalink: | https://search.fid-benelux.de/Record/base-27525632 |
Datenquelle: | BASE; Originalkatalog |
Powered By: | BASE |
Link(s) : | https://nbn-resolving.org/urn:nbn:de:hbz:464-20130320-091831-4 |
Intensive agriculture causes increased soil erosion worldwide, resulting in a higher level of fine sediment in aquatic systems. Although the accumulation of fine sediment (incorganic and organic particles) on the streambed is a widely-known phenomenon in streams and rivers, no comprehensive field studies have been conducted on the effect of deposited fine sediment on the benthic macroinvertebrates in small headwater streams in Central Europe. This thesis’ current questions are, firstly, which environmental variables influence the input and the deposition of fine sediment and, secondly, does the sedimentation impact the indicator species’ and macroinveterbates’ community composition. Located in the Ardennes Mountains, this case study focused on 11 tributaries of the river Our in northern Luxembourg and the bordering Rhineland-Palatinate (Germany). The increased soil erosion of this catchment area is caused by the soil type (a layer of clay and silt) as well as the tillage, which is mainly conducted on the slopes. A total of 29 samples sites were recorded the fine sediment and environmental variables as well the benthic macroinvertebrates, in the period from 2008 to 2010. The surficially deposited fine sediment was recorded for one year from autumn 2008 to autumn 2009 using artificial turf mats. Every three weeks two sections were collected from each site: one with rapid flow velocity (riffles) and the other with a sinking area for particles (pools). The amount of fine sediment was weighed; the proportion of organic matter and the proportion of carbon to nitrogen (C/N ratio) as a measurement of microbial decomposition in the deposition were calculated. Additionally, the numerous environmental variables acting on diverse spatial scales were recorded during the sampling periods, such as on the catchment scale (e.g., the land use in the catchment, the catchment area), on the riparian zone (e.g., the land use directly on the stream bank or in a distance of five meters, the shadowing); on the in-stream scale (e.g., the ...