Soil Erosion

Erosion can be described as the process by which soil particles are ripped away from its substrate and disseminated by water or wind. In Maryland, most soil erosion can be attributed to the movement of water across the landscape. Since most of the state is part of the Chesapeake Bay Watershed, there are a myriad of low lying depressions, drainages, streams, and rivers which can easily carry soil particles away. Precipitation is also frequent, with over 40 inches of rain annually, meaning water is constantly being cycled. The importance of Maryland’s water resources are paramount as many communities, occupations, and recreational opportunities have come to depend upon them.

Managing soil erosion is extremely important, as there are many adverse conditions that can result. Some of these conditions include the widening/deepening of stream channels, the inundation of soil particles into streams, and the contamination of water by chemicals and contaminants, which are often bound to soil particles. Erosion typically begins in or around the stream channel, and can occur at any time. However, great increases in erosion are apparent following precipitation. Non-forested streams will often pick up sediment very easily from both overland runoff and instream erosion. As this occurs over time, stream channels can widen/deepen greatly if protection measures are not in place, i.e. trees. As soil particles are moved into waterways, they become suspended. These suspended particles cloud the water, turning it brown. When high concentrations are present, health of fish and other in-stream wildlife can be put at risk. Chemical contamination, on the other hand, is an even greater concern. This can occur when soil particles that have chemicals bound to them make their way into water. These chemicals can vary greatly, but typically include fertilizers and manure, which often contain high levels of nitrogen and phosphorus. An increase of nutrients in water can cause an explosion of plant and algae growth, leading to eutrophication. Eutrophication is the inundation of nutrients, causing extensive growth of water plants and algae. When this occurs, oxygen in the water is taken up quickly by this water vegetation, leaving little for fish and other wildlife that need it to survive. When oxygen levels get low enough (anoxic conditions), fish will die. Examples of this can be found in streams, rivers, and even the Chesapeake Bay.

On the positive side, county, state, and federal governments, in coordination with numerous other partners, are working hard to reduce soil erosion. Efforts have primarily been focused on streamside restoration. Planting trees and establishing riparian forest buffers have become the greatest focus, as they are effective mitigators of soil erosion and runoff. This is done primarily by the ability of root systems to hold soil in place, even when over saturated. Additionally, trees can uptake thousands of gallons of water each year, reducing overland flow potential.

Article by FCFCDB

Nature note for 7/18/2020