The role of habitat connectivity and landscape geometry in experimental zooplankton metacommunities

Abstract

Chase, J. M. 2002. The role of habitat connectivity and landscape geometry in experimental zooplankton metacommunities. -Oikos 96: 433-440.Theory predicts that inter-patch dispersal rates and patterns of patch heterogeneity both have the potential to alter patterns of local and regional species diversity. To test this, we manipulated both rates of habitat connectivity and the geometric arrangement of habitat heterogeneity within regions of experimental zooplankton communities. We found no effects of habitat geometry on any metric of species diversity or composition. Additionally, we found no effect of habitat connectivity rate on local species diversity. We did, however, find that increasing connectivity led to a decrease in regional diversity, as well as an increase in the percent similarity of local communities within regions. Of all of the species in these communities, the relatively large cladoceran Ceriodaphnia reticulate significantly responded to the treatments, and had a higher probability of achieving high densities when connectance was high. As such, we suggest that this species played a large role in driving the increased local community similarity and decreased regional species richness as connectivity increased. These findings are in opposition to previous experimental studies of metacommunities, but support the notion that increased connectance among local patches may decrease regional diversity when patches are heterogeneous.

Bidirectional exchanges of benthic invertebrates in a large river–floodplain system (Paraná River, Argentina)

“…Beta diversity increased with geographical distance, indicating that the homogenization in species composition was less effective at greater distances, so that species assemblages from more distant sites reflected different environmental conditions prevailing there. Furthermore, the species favored by certain habitats would have a higher probability of migrating to adjacent habitats of similar quality (Forbes and Chase, 2002;Mormul et al, 2011).…”

Short-term effects of drawing water for connectivity of rivers and lakes on zooplankton community structure

“…Other research found that in all the species of these communities, the relatively large cladoceran Ceriodaphnia reticulata significantly responded to the treatment, it achieved high densities when the connected area was large enough. C. reticulata was an important role in driving the increased local community similarity and decreased regional species richness as connectivity increased (Forbes and Chase, 2002). Dilution also had some effect on the assemblage of rotifers.…”

“…Highest abundances during the high water period were observed in isolated lagoons, whereas connected lagoons had highest abundances during the low water period. Forbes and Chase (2002), however, found no effects of habitat geometry on any measure of species diversity or composition and no effect of habitat connectivity on local species diversity. However, increasing connectivity led to a decrease in regional diversity, but an increase in the percent similarity of local communities within regions.…”

Lakes and rivers as microcosms, version 2.0

“…For lack of an already established name, I call this discipline landscape limnology because it is related to landscape genetics (Manel et al, 2003) and occurs within the context of landscape connectivity, including interactions with terrestrial systems. An important part of this work is research about metapopulation, metacommunity, and meta-ecosystem concepts (e.g., Gotelli and Taylor, 1999;Forbes and Chase, 2002;Howeth and Leibold, 2008;Cottenie et al, 2003;Van de Meutter et al, 2007;Larned et al, 2010, some papers in this volume).…”