Dispersal Ability Determines the Role of Environmental, Spatial and Temporal Drivers of Metacommunity Structure

Abstract

Recently, community ecologists are focusing on the relative importance of local environmental factors and proxies to dispersal limitation to explain spatial variation in community structure. Albeit less explored, temporal processes may also be important in explaining species composition variation in metacommunities occupying dynamic systems. We aimed to evaluate the relative role of environmental, spatial and temporal variables on the metacommunity structure of different organism groups in the Upper Paraná River floodplain (Brazil). We used data on macrophytes, fish, benthic macroinvertebrates, zooplankton, periphyton, and phytoplankton collected in up to 36 habitats during a total of eight sampling campaigns over two years. According to variation partitioning results, the importance of predictors varied among biological groups. Spatial predictors were particularly important for organisms with comparatively lower dispersal ability, such as aquatic macrophytes and fish. On the other hand, environmental predictors were particularly important for organisms with high dispersal ability, such as microalgae, indicating the importance of species sorting processes in shaping the community structure of these organisms. The importance of watercourse distances increased when spatial variables were the main predictors of metacommunity structure. The contribution of temporal predictors was low. Our results emphasize the strength of a trait-based analysis and of better defining spatial variables. More importantly, they supported the view that “all-or- nothing” interpretations on the mechanisms structuring metacommunities are rather the exception than the rule.

Spatial and temporal variation of invertebrate community structure in flood-controlled tropical floodplain wetlands

“…In contrast to macroinvertebrates, the zooplankton community structure did not significantly change from the dry period to the period after controlled flooding. Zooplankton are generally efficient passive overland dispersers especially over small scales (Havel & Shurin 2004;Padial et al 2014). They produce dormant resting eggs that are accumulated in a persistent egg bank (Brendonck & De Meester 2003) which increases their likelihood of dispersal by wind and animal vectors (Waterkeyn et al 2010;Vanschoenwinkel et al 2011).…”

Phytoplankton assemblages in a complex system of interconnected reservoirs: the role of water transport in dispersal

“…Water transportation and its role in the studied system As widely recognized for microorganisms (Fontaneto & Hortal, 2012), phytoplankton has a high passive dispersal ability compared to ''bigger'' components of (Padial et al, 2014). Dispersal of phytoplankton can be mediated by a variety of physical (wind and water) and biological vectors (aquatic birds, mammals, insects, etc.)…”

“…In naturally connected ecosystems such as floodplain lakes and complex river systems, water flow is considered the main dispersal vector and both seasonality (duration) and directionality of river flow, as well as water course distances, have an important role in shaping metacommunity in the different ecosystems belonging to the ''network'' (Liu et al, 2013;Padial et al, 2014;Devercelli et al, 2016). However, in the present study, the network system was formed by human-operated reservoirs and both duration and directionality of water flow were strongly subjected to unpredictable constraints linked to the need of the drinking water supply of urban centers.…”

The taxonomic and functional biogeographies of phytoplankton and zooplankton communities across boreal lakes

“…Previous work has indicated that phytoplankton generally respond to environmental factors while zooplankton are more dispersal-limited (Beisner et al 2006, De Bie et al 2012, Padial et al 2014. Such differential response patterns could also interfere with a strong biogeographical coupling of the groups.…”