Effect of Hyporheic Exchange on Macroinvertebrate Community in the Weihe River Basin, China

Abstract

The effect of hyporheic exchange on macroinvertebrates is a significant topic in ecohydraulics. A field study was conducted during May and June 2017 to investigate the impacts of magnitude and patterns of hyporheic exchange on the sediment macroinvertebrate community in the Weihe River basin. The results demonstrate that upwelling flows cause resuspension of riverbed sediment, increasing the proportion of swimmer groups (such as Baetidae) in the macroinvertebrate community. However, large resuspension of river bed sediment results in a reduced abundance of macroinvertebrates. By controlling the transport processes of dissolved oxygen (DO), dissolved organic carbon (DOC), nutrients, temperature, and different patterns of hyporheic exchange strongly influence the structure of macroinvertebrate communities. Downwelling is more likely to produce rich invertebrate communities than upwelling. The magnitude for the hyporheic flux of 150-200 mm/d was optimal for the macroinvertebrate community in the Weihe River Basin. Above or below this rate results in a decline in community abundance and diversity. We suggest that research is conducted to better understand the effects of hyporheic exchange across bedforms on macroinvertebrate communities. The study supports any activities to preserve the ecological functions and health of rivers dominated by fine-grained sediments.

Revealing the influence of hyporheic water exchange on the composition and abundance of bottom-dwelling macroinvertebrates in a temperate lowland river

“…Second, we also revealed that HWE in the examined low dynamic, temperate, perennial lowland river cannot be considered a factor to explain distributions, spatial patterns and composition of bottom-dwelling macroinvertebrates better than the other environmental variables, such as river depths, flow velocities and cross-section's area, which confirmed to a certain extent the conclusions of Monk et al (2006). Although statistical significance in different indicators of BMI abundances and compositions analysed in our study was not found, observed relationships remained similar to the ones Ling et al (2020) provided: infiltrating conditions, where river waters penetrate hyporheic zone in a downwelling flux, prerequisited more suitable conditions for BMI persistence than the conditions of groundwater exfiltration (upwelling flux in a hyporheic zone). They also observed that hyporheic upwelling flows, representing the river's draining conditions, caused resuspension of finer sediments and increased the proportion of swimmers in total abundance of BMI.…”

“…The first steps towards evaluating the influence of hyporheic water exchange (HWE) on BMI in different scales provided interesting results. Ling et al (2020) observed that hyporheic upwelling flows, representing the river's draining conditions cause resuspension of finer sediments and increase the proportion of swimmers (in their case, Baetidae) in total abundance of BMI. They also observed that downwelling flows (representing conditions of river infiltration to the aquifer through the hyporheic zone) produced richer compositions and abundances of BMI than the upwelling ones.…”

The Effect of Tubificid Bioturbation on Vertical Water Exchange across the Sediment–Water Interface

“…Water flux obtained by the conservative-solute transport model before and after the introduction of invertebrate showed that the presence of tubificids significantly increased the proportion of mobile region, indicating modified water flux [24]. Research has also shown that the macroinvertebrate community may be related to the magnitude and patterns of water exchange [25]. The presence of tubificid worms can effectively enhance the water flux while the chironomid larvae failed to show the similar effects, which indicated that the influence depends on the mode of the bioturbation [15,26].In addition, macroinvertebrate activity may alter flow paths in the interstitial spaces [27].…”

Advances in Environmental Hydraulics

“…Four studies approached the stream and river systems from a variety of perspectives, ranging from the physical modelling of flow with vegetation [13] and the numerical simulation of solute transport in river with dead zones [14], to the laboratory study of flood discharge atomisation [15] and the geomorphic characterisation and classification of a large river [16]. Three contributions are about hyporheic fluxes: two field studies investigated these fluxes at a small river confluence [17] and the effects of such fluxes on the macroinvertebrate community [18], while their relationship with the bioturbation activity of macroinvertebrates was studied in laboratory [19]. The last two articles addressed the accuracy of groundwater flux measurement using a seepage meter in the laboratory [20] and the experimental validation of the Darcy-Buckingham (DB) law in unsaturated porous rocks [21].…”

“…Hyporheic exchange affects the substrate properties and water quality and thus the habitat availability and suitability of macroinvertebrate community in river ecosystems. In this context, Lin et al [18] conducted a field study to explore the impacts of magnitude and pattern (upwelling and downwelling) of hyporheic exchange on the sediment macroinvertebrate community in the Weihe River Basin in Shaanxi, China. The results showed that while upwelling flows caused the resuspension of riverbed sediment and increased the proportion of swimmer groups in the macroinvertebrate community, downwelling is more likely to produce abundant and rich invertebrate communities.…”