River network connectivity and fish diversity

Human activities' fingerprint on multitrophic biodiversity and ecosystem functions across a major river catchment in China

“…In a traditional understanding, different taxonomic groups are thought to have unique spatial patterns in river networks due to the distinct dispersal properties of certain taxonomic groups (He et al., 2020; Liu et al., 2013; Tonkin et al., 2018). For example, microbiota are mainly controlled by local environmental factors and thus exhibit a spatial pattern of greater species diversity in headwater than downstream (Besemer et al., 2013; Savio et al., 2015), while fish and insects have a higher biodiversity in the downstream than in the upstream due to their strong dispersal capacity in the river networks (Altermatt, 2013; Shao et al., 2019). However, it has recently been suggested that environmental variables outperform the spatial factors in structuring algal community in river networks (Jamoneau et al., 2018; Wu et al., 2018).…”

“…By contrast, aquatic ecosystems have received less attention (Daam et al., 2019; Little et al., 2020; Vaughn, 2010), and most of the available studies were limited to micro‐ or mesocosms models (Cardinale et al., 2002; Jabiol et al., 2013; Pennekamp et al., 2018). Because effects of biodiversity loss themselves depend on the abiotic and biotic context and the spatial scale (Bond & Chase, 2002; Chase & Leibold, 2002; Daam et al., 2019; Vaughn, 2010), non‐trivial dependencies are expected, especially in heterogeneous and highly spatially structured river networks (Altermatt, 2013; Shao et al., 2019).…”

The role of migration barriers for dispersion of Proliferative Kidney Disease—Balance between disease emergence and habitat connectivity

“…For brown trout, which migrate considerable distances, free connectivity of river systems is essential to reach spawning habitats. In addition, increased connectivity also increases biodiversity facilitating migration also for smaller fish species [44] and invertebrates. On the other hand, spreading of infectious agents possibly detrimental for vulnerable fish populations can be enhanced by migration.…”

Channel network structure determines genetic connectivity of landward–seaward Avicennia marina populations in a tropical bay

“…The role of river network structure in shaping the genetic variation within and between populations has been commonly investigated for a broad range of freshwater organisms, including fish (Shao et al, 2019;Thomaz et al, 2016), insects (Finn et al, 2006(Finn et al, , 2007, and plants (Sander et al, 2018). In these studies, the observed population genetic patterns are generally described using four connectivity models that predict how populations with different life history traits and dispersal capabilities interact within their structured riverine habitat (Finn et al, 2007;Hughes et al, 2009).…”