Slide 56 of 75
Notes:
A shift in the energy source that drives the streams is another major change to the ecology of urban streams. Unlike many terrestrial ecosystems which are driven by sun and plant growth, the source of energy for most streams in eastern North America is from outside the stream. In a healthy stream, when leaves shed from the trees, they blow into stream channels and form leaf packs within the stream. Leaves are a main source of food for aquatic insects in many undeveloped, humid climate streams.