Various investigators have reported that urbanization resulted in a major negative impact on aquatic ecosystems. Large areas of impervious surfaces and high levels of hydraulic connection of impervious surfaces to streams, through stormwater pipes or drains, are two characteristics of the urban environment that can lead to major negative impacts on urban/residential streams. These two characteristics of urban streams cause decreased levels of evapotranspiration and infiltration and rapid delivery of water to these lotic water bodies. Human activities in the urban environment can degrade aquatic ecosystems by altering one or more of the following principal groups of attributes: water or sediment quality; habitat structure; flow regime; energy source (food); or biotic interactions.
Citation: Hall LW, Killen WD, Anderson RD, Alden III RW (2013) A Three Year Assessment of the Influence of Physical Habitat, Pyrethroids and Metals on Benthic Communities in Two Urban Calfornia Streams. J Ecosys Ecograph 3:133.