cad a22 4500 569329957 20200215084100.0 cr unu---uuuuu 190727e201906 xx s 000 0 eng 10.1007%2Fs10452-019-09679-3 doi (ZORA)oai:www.zora.uzh.ch:172051 570 ddc 590 ddc Little Chelsea J. Differential resource consumption in leaf litter mixtures by native and non-native amphipods [Elektronische Daten] [Chelsea J. Little, Florian Altermatt] openAccess eu-repo Leaf litter processing is an essential ecosystem function in freshwater systems, since much of the carbon and nutrients moving through freshwater food webs come from the surrounding terrestrial ecosystems. Thus, it is important to understand how the species performing this function differ, especially because many native species are being replaced by non-native species in aquatic ecosystems. We used a field experiment to examine leaf consumption rates of two common shredding macroinvertebrates (the native Gammarus fossarum and the non-native Gammarus roeselii). Leaves from three species, varying in resource quality, were added both in leaf monocultures and as a three-species mixture. Biomass-adjusted daily consumption rates were similar between the two amphipod species, and each consumed nitrogen-rich alder leaves faster than oak or beech leaves. However, because adult G. roeselii are approximately twice the size of G. fossarum, this led to systematic, though nonsignificant, differences in consumption rates at the per-capita or population level. Furthermore, we found nuanced effects of decomposer identity on leaf decomposition in mixtures. Only G. roeselii showed increased consumption of the preferred resource (alder) in the mixture, while G. fossarum consumed all leaves at the same proportional rates as in monocultures. This is an important distinction, as most measures of macroinvertebrate leaf shredding are made in the laboratory with only a single leaf resource available. Our results, based on a field experiment which could control the presence of dominant macroinvertebrates while still providing natural, biologically realistic context, suggest that even functionally similar species may subtly shift ecosystem processes. Institute of Evolutionary Biology and Environmental Studies zora Biodiversity, Decomposition, Headwater streams, Ecosystem function, Meta-ecosystem, Preferential feeding zora Altermatt Florian joint author Aquatic Ecology 53(2):151-162 https://www.zora.uzh.ch/id/eprint/172051/1/Little_und_Altermatt.docx text/html WWW-Backlink auf das Repository Onlinezugriff via WWW text/html https://link.springer.com/article/10.1007%2Fs10452-019-09679-3 ZORA 1 Journal Article PeerReviewed zora SNSF/Projectfunding/PP00P3_150698/CH zora grantAgreement ZORA 856 40 https://www.zora.uzh.ch/id/eprint/172051/1/Little_und_Altermatt.docx text/html WWW-Backlink auf das Repository ZORA 856 42 Onlinezugriff via WWW text/html https://link.springer.com/article/10.1007%2Fs10452-019-09679-3 ZORA 100 1- Little Chelsea J. ZORA 700 1- Altermatt Florian joint author ZORA 773 0- Aquatic Ecology 53(2):151-162 BK010053 XK010053 XK010000 ZORA ZORA ZORA Journal Article openAccess