The role of organisms in hyporheic processes: gaps in current knowledge, needs for future research and applications

Abstract

-Fifty years after the hyporheic zone was first defined (Orghidan, 1959), there are still gaps in the knowledge regarding the role of biodiversity in hyporheic processes. First, some methodological questions remained unanswered regarding the interactions between biodiversity and physical processes, both for the study of habitat characteristics and interactions at different scales. Furthermore, many questions remain to be addressed to help inform our understanding of invertebrate community dynamics, especially regarding the trophic niches of organisms, the functional groups present within sediment, and their temporal changes. Understanding microbial community dynamics would require investigations about their relationship with the physical characteristics of the sediment, their diversity, their relationship with metabolic pathways, their interactions with invertebrates, and their response to environmental stress. Another fundamental research question is that of the importance of the hyporheic zone in the global metabolism of the river, which must be explored in relation to organic matter recycling, the effects of disturbances, and the degradation of contaminants. Finally, the application of this knowledge requires the development of methods for the estimation of hydrological exchanges, especially for the management of sediment clogging, the optimization of self-purification, and the integration of climate change in environmental policies. The development of descriptors of hyporheic *Corresponding author: pierre.marmonier@univ-lyon1.frArticle published by EDP Sciences Ann. Limnol. -Int. J. Lim. 48 (2012) [253][254][255][256][257][258][259][260][261][262][263][264][265][266] Available online at: Ó EDP Sciences, 2012 www.limnology-journal.org DOI: 10.1051/limn/2012009 zone health and of new metrology is also crucial to include specific targets in water policies for the long-term management of the system and a clear evaluation of restoration strategies.

A survey on pre-processing techniques: Relevant issues in the context of environmental data mining

“…As an example, in the analysis of river's retention [153], one could get different databases. One containing morphologic characteristics of the river, built by experts; another containing biochemical characteristics of the rivers at different timestamps, provided by a biochemical laboratory; another containing information on microbiological diversity, provided by a set of biologists, and based on microscope observation of samples; another with some satellite pictures to learn land uses around the river; and another with some sensor data about flows along time.…”

Benthic and hyporheic macroinvertebrate distribution within the heads and tails of riffles during baseflow conditions

“…Dole-Olivier, 1998;Davy-Bowker et al, 2006;Mathers & Wood, 2016), the consequences of flow dynamics at small spatial scales and the associated sedimentary characteristics upon benthic and hyporheic invertebrate assemblages remain poorly quantified (Marmonier et al, 2010(Marmonier et al, , 2012Descloux et al, 2014;Jones et al, 2015). Despite several seminal papers over multiple decades which identified the potential importance of vertical hydraulic connectivity (Orghidan, 1959;Tilzer, 1968;Hynes, 1983), linkages between surface and groundwater and its influence on instream communities remain poorly studied (Boulton et al, 1999;Krause et al, 2011a).…”

Fine sediment deposition and interstitial flow effects on macroinvertebrate community composition within riffle heads and tails

“…Despite significant advances in our understanding of how hydraulic exchange and associated sediment dynamics influence benthic invertebrates under laboratory conditions, (Nogaro et al, 2006;Jones et al, 2015), evidence from the field remains limited (Marmonier et al, 2010(Marmonier et al, , 2012. Riffle scale variability in hydraulic exchange (upwelling, downwelling and horizontal flows) may be an important influence on the spatial distribution of benthic invertebrates (Pepin & Hauer, 2002;Capderry et al, 2013) which has received limited attention to date (Grimm et al, 2007;Krause et al, 2011).…”