Experimental Stream Facility at Konza Prairie

The experimental stream facility on the Konza Prairie Biological Station was constructed in association with a National Science Foundation funded project (DEB 0416126) to test how increased hydrologic variability associated with global climate change will interact with key organisms to regulate ecosystem function in intermittent prairie streams. Because these streams are non-equilibrium systems with highly unpredictable flow patterns, it is necessary to use controlled mesocosm experiments to run mechanistic studies to verify field observations. In the experimental streams, simulated floods and droughts will be crossed with the presence or absence of two common and locally abundant prairie fishes, a grazing minnow (Phoxinus erythrogaster) and a water-column minnow (Cyprinella lutrensis). These species represent two major functional groups of stream organisms and are likely to interact with changes in disturbance frequency and intensity in this region. Responses of natural streams to flood and drought will be characterized to allow calibration of results from experimental streams. Stream metabolism (photosynthesis and respiration) and nutrient retention are the primary response variables because they are central to ecosystem structure and function as well as issues of water quality. Results from our study will help predict how prairie streams will respond to future climate scenarios that include changes in hydrologic variance and species composition. A central hypothesis is that dominant or strongly interacting species will regulate the response of stream ecosystems to climatic change.

24 riffle/pool units

Side view of one unit

Top view of one unit

Picture through viewing window of Phoxinus erythrogaster