Erosion and Sedimentation

There has been an increase in erosion and sedimentation in aquatic regions of the coastal redwoods due to the remarkable decrease in redwood trees in the late 1900s. There a different sources and explanation to this increase.

With much fewer trees, there would be a reduction in foliage . Thus leading to a decrease in interception and evaporation .This in turn leads to an increase in rainfall . Consequently increasing surface runoff and erosion, contributing to the increase in sedimentation in the streams .

Also, the current continues logging acts upstream around the protected forest parks also contribute to increase in sedimentation in aquatic park areas downstream . Logging upstream will cause loose soil from that to erode and increase sedimentation in the stream. As the stream flows down the sediments continue to accumulate, therefore affecting downstream in the protected parks .

Abandoned roads from the timber companies also contributed to sedimentation yield in the streams. These roads that were typically built across steep slopes, would often add sediments directly into the streams through induced landslides . Fom 1954 to 1978 road-related landslides made up 40% of total landslide volume that occurred. Roads also prevented rain water to infiltrate into the soil, thus contributing to surface runoff increase erosion and sedimentation .

Certain areas have been documented to be more affected then others. For instance, redwood creek is currently listed under the clean water act as impaired due to high sediment levels and temperatures . These conditions were shown to affect three out of four salmon and steel head trout species to the point where they are federally listed as threatened under the Endangered Species Act”