Faunal Response to Fine Sediment Deposition in Urban Rivers

Fine sediment deposition and infiltration into the bed of lotic ecosystems, such as sedimentation, siltation and colmation, has been widely recognised as one of the most important causes of degradation within lotic ecosystems. The impact of increased fine sediment loading as a result of agricultural practices, urban development and channel management activities for flood defence purposes, have been widely acknowledged but poorly quantified. This chapter quantifies the influence of increasing sediment input that is sediment loading on the benthic invertebrate community inhabiting an artificial channel with an impervious concrete bed. This approach provided highly controlled conditions but also reflected channel and habitat characteristics typical of many highly modified and managed urban streams. Significant advances have been made recently in the development of biomonitoring tools which quantify fine sediment impacts on instream communities and which facilitate identification of vulnerable locations within river channels.