Soil conservation consists of a number of practices that improve the quality of the environment. It takes up the challenge of preventing soil loss through erosion. It also finds ways to improve water quality. As with water pollution, the consequences of poor land management can extend to areas beyond the site of damage.
This fact complicates soil conservation. Solutions often require a multi-faceted approach, involving different organizations and governments, as well as diverse groups of stakeholders. Conflicting interests are one of many obstacles a soil management plan may face.
Why Soil Loss Occurs
Several factors can contribute to soil loss. In urban settings, an increase in impervious surfaces like roads and parking lots can increase water flow to vulnerable areas. A small low-lying area may become a ditch, and the exposed banks of the ditch can be easily eroded.
Abuse of the land is another potential cause. Removal of plant life from equestrian or off-road travel removes the anchors keeping the soil in place. Likewise, this can occur with livestock operations or plant loss from pesticide management. Poor farming practices can also increase runoff.
Risks of Soil Loss
The consequences of soil loss depend upon the particular environment. One risk most sites would see is a build-up of sedimentation. This can alter the chemistry of the aquatic habitats and make these places unfit for plant or animal life.
Sedimentation can also introduce harmful chemicals into waterways, both from urban and rural settings. Cities may see an increase in toxins from the roads. Farms may experience plant and animal die-offs from excess fertilizers or pesticides entering surface water.
Over time, soil loss can alter landscapes. For example, sedimentation from soil erosion can change the course of water flow. An area of free-flowing water may be transformed into a different habitat because of pioneer plants like cattails and reed canary grass. The wildlife that depends upon these habitats will also suffer from its impacts.
Economic Costs of Soil Erosion
If wetlands are lost because of soil erosion, the risk for flooding increases. These ecosystems act like sponges that absorb excess flood waters or simply water flowing over impervious surfaces. Floods are one of the most common and costly of natural disasters. According to the National Oceanic and Atmospheric Administration, flooding costs topped $5 billion in 2010.
Soil loss and erosion impact waterways as well. Runoff can introduce contaminants in the water that can negatively affect aquatic populations. Large die-offs can then make the water unsuitable for human use. American Rivers estimates that almost 40 percent of American rivers and streams are too polluted for recreational use.
Soil Conservation Solutions
Solutions to prevent these effects rely on thoughtful city planning. Reducing areas of impervious surfaces can prevent increased water flow in urban settings. Constructing rain gardens in vulnerable areas can slow water and prevent it from eroding the soil.
In rural areas, use of contour farming can prevent ditches from becoming gullies. Likewise, planting buffer strips along stream banks can help the soil stay in place when water flow increases. Farmers can also rotate fields where livestock roam to prevent loss of topsoil due to grazing pressure.
Measures such as these can reduce the stress on the land and its waterways. The plants and wildlife that depend upon these habitats will benefit, as will the inhabitants of the land.
Sources:
- FEMA, Floods
- Pimentel, David. 2006. “Soil Erosion: A Food and Environmental Threat.” Environment, Development and Sustainability. Accessed November 2011
- Rain Garden Network, What is a Rain Garden?
- U.S. Environmental Protection Agency, Functions and Values of Wetlands
- U.S. Environmental Protection Agency, Polluted Runoff (Nonpoint Source Pollution)
