Multiple-Stressor Interactions in Tributaries Alter Downstream Ecosystems in Stream Mesocosm Networks

We studied how multiple-stresssors in tributaries affect function, diversity, and physical habitat of recipient downstream ecosystems. Using a mesocosm model stream network, we manipulated sediment nutrients individually combination second-order channels, to test the effect complex stressor interactions within on channels. Sedimentation channels increased with level disturbance tributaries. Moreover, Ephemeroptera, Plecoptera, Trichoptera (EPT) density EPT richness were higher fed by where stressors applied separately, compared those simultaneously. Our observations suggest this result was due two same tributary reducing drift from further than addition separate These results support hypothesis that cumulative upstream can influence ecosystems networks. However, contrary our expectations, most observed effects impacts dispersal patterns taxa, rather accumulation disturbances throughout network. underscore importance metacommunity frameworks understand may population dynamics