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Biology subjects

Chaouat, L.

Publications and source records attributed to Chaouat, L..

2 recordsLinked to original sources

Changing seasonality and phenology mediate the effects of migration across meta-ecosystems

Migration is a ubiquitous process that links ecosystems with distinct seasonal dynamics, transferring biomass and species interactions across space. Despite being widely altered by global change, studies commonly overlook the interaction of seasonal characteristics and bidirectional migration on species coexistence and biomass production across meta-ecosystems. We developed a mathematical model to study how migration interacts with key characteristics of seasonality--amplitude of variation and length of summer--to influence migrant persistence, consumer coexistence, and biomass production. Our findings demonstrate that seasonal characteristics mediate the effect of migration on coexistence and biomass production across meta-ecosystems. However, the effects strongly depend on migration timing: phenological mismatches can reduce biomass at local and meta-ecosystem scales and lead to the extinction of migratory and non-migratory consumers. Our study highlights how migration and seasonality interact to shape community structure and ecosystem function across scales, emphasizing the importance of system-level approaches for studying ecological outcomes of global change.

ecology↗

Food-web coupling by mobile consumers has individual to ecosystem level effects

Mobile consumers serve as a ubiquitous link, coupling the dynamics and functions of different ecosystems, ranging from diel-vertical migration of zooplankton to seasonal movements of large ungulates. Despite mounting theoretical interest, experimental tests of the effects of consumer mobility in meta-ecosystems are virtually non-existent. Here, we used an experimental microcosm system to investigate how mobile consumers (Daphnia magna) mediate ecosystem biomass, community structure, and their own fitness by coupling spatially distinct aquatic ecosystems composed of two different protist communities. We found that consumer mobility significantly influenced the effect of consumption on ecosystem biomass and the growth and reproduction of the consumers, themselves. However, the direction and magnitude of these effects depended on community composition in the connected ecosystem. Further, we found consumer mobility consistently promoted the coexistence of a competing local species, regardless of community composition in the connected ecosystem. Our findings underscore the profound role of consumer mobility in shaping individual to ecosystem-level dynamics while emphasizing a strong mediating effect of community composition across the landscape.

ecology↗