Seasonal changes in relative contribution of environmental control and spatial structuring on different dispersal groups of stream macroinvertebrates

Abstract

The role of environmental control and spatial structuring may vary depending on dispersal mode within a metacommunity in stream systems. However, as a result of high seasonal variation in environment conditions and phenological features, there might be considerable seasonal changes in the relative importance of structuring factors. The objective of this study was (i) to determine the relative role of structuring factors for aquatic macroinvertebrates with different dispersal mode groups which have seasonal variation in their dispersal capacity and (ii) to disentangle seasonal changes in metacommunity structuring. We sampled 50 stream sites of the Middle Danube Basin (Hungary) in spring and summer. We compared Distance-Decay Relationships between communities of different dispersal groups and distance measures, and then we used variation partitioning analysis and Moran's eigenvector maps based on overland and watercourse distances to reveal structuring processes in both seasons. We found that metacommunities of all dispersal groups were influenced in both seasons mainly by environmental factors with additional impacts of the spatial components. Our findings suggest that metacommunities of taxa with temporally stable dispersal capacity have seasonally stable structuring processes, while the relative importance of structuring factors can vary seasonally in groups with seasonally changing dispersal capacity.

Environmental Factors Override Dispersal-Related Factors in Shaping Diatom and Macroinvertebrate Communities Within Stream Networks in China

“…Moreover, because of the large geographical extent among three regions, sampling of three regions was not possible in single year due to limited resources. However, metacommunity assembly is expected to be temporally relatively stable in perennial river systems (Sarremejane et al, 2017;Csercsa et al, 2019), such as in streams studied here. We thus believe that our main conclusions of macroinvertebrate metacommunity assembly may have been only little affected by the seasonal effects.…”

Seasonal shifts in the assembly dynamics of benthic macroinvertebrate and diatom communities in a subtropical river

“…Current theoretical and empirical frameworks emphasize that biological communities are structured by a combination of deterministic and stochastic processes (Csercsa et al, 2019;Devercelli, Scarabotti, Mayora, Schneider, & Giri, 2016;Patrick & Swan, 2011;Swan & Brown, 2011). The deterministic perspective assumes that the distributions of species are under environmental filtering (i.e., local environmental conditions) and biotic interactions (e.g., Chase & Myers, 2011;Giam et al, 2016;Heino, Gröroos, Soininen, Virtanen, & Muotka, 2012;Isabwe et al, 2018), while the stochastic perspective assumes that species distributions are mainly determined by random births, deaths, and dispersal assembly (Grönroos et al, 2013;Hubbell, 2001;Tonkin et al, 2018).…”

“…Although seasonal changes in benthic macroinvertebrate and diatom community structures have been well documented, little attention has been given to seasonal shifts in the underlying assembly mechanisms (Bêche et al, 2006;Csercsa et al, 2019;Göthe et al, 2013;Walters, 2011). This is the case that can be evaluated when macroinvertebrates and diatoms are sampled from the same sites.…”

Integrating Disturbance, Seasonality, Multi-Year Temporal Dynamics, and Dormancy Into the Dynamics and Conservation of Metacommunities

“…Overall, work from intermittent rivers and floodplains indicates that, where there exist significantly different abiotic conditions between seasons, the relative strength of environmental filtering and dispersal as biological processes driving metacommunity structure fluctuate seasonally (Table 1; Fernandes et al, 2014;Datry et al, 2016;Sarremejane et al, 2017). Where specific species are located in time and space is additionally mediated by species traits such as dispersal ability (Csercsa et al, 2019) and ability to cope with environmental conditions (Kraft et al, 2015). Though there is evidence that the biological processes of dispersal and environmental filtering seasonally influence metacommunity structure in terrestrial systems (Delciellos et al, 2018), this line of evidence is less robust.…”