LANDUSE INFLUENCES ON STREAM PROCESSES AND BIOTA
Landuse, through runoff, can have significant influences on stream macroinvertebrate assemblages. We hypothesize that runoff is an important route for particles and dissolved chemicals from terrestrial landscapes to streams, and can modify instream processes. These modifications in agricultural landscapes compared to forests, are due to organic load changing the oxygen regime and food quality, and contaminants. All three directly affect the benthic macroinvertebrate assemblages. Our research questions were: 1. Does runoff differ between agricultural and forest landscapes? 2. How does land-use related runoff modify the instream processes? 3. Does the macroinvertebrate assemblage respond to land-use related runoff? Runoff is a source of organic matter, phosphorus, nitrogen, carbon and contaminants in streams. Agricultural runoff in comparison to agricultural runoff results in an increase in organic load and as such in oxygen depletion, a decrease in food quality based on the C/N ratio, and an increase in contamination based on bioassay tests on growth, reproduction and emergence. All three changes will add to the observed decrease in macroinvertebrate diversity. In conclusion, buffering agricultural runoff will add to the recovery of stream ecosystems.
Paula dos Reis Oliveira (Primary Presenter/Author), University of Amsterdam, firstname.lastname@example.org;