Erosion Control and Conservation Practices
Erosion control and conservation practices are the agronomic, structural, and biological measures that protect soil from erosion and conserve soil and water, keeping land productive.
Definition
Erosion control and conservation practices are the management techniques and engineered measures used to reduce soil detachment and transport by water and wind and to conserve soil and water for sustained land productivity.
Scope
This topic covers conservation and reduced tillage, residue and cover management, contouring, terracing, strip cropping, grassed waterways, windbreaks, and other measures, organized by how they reduce the detachment and transport of soil. It is the practical application of soil conservation science to sustaining the land.
Core questions
- How do residue cover and reduced tillage limit erosion?
- How do contouring, terracing, and strip cropping slow runoff?
- How are vegetation and windbreaks used to control wind and water erosion?
- How are conservation practices combined and planned for a given field?
Key concepts
- Conservation and reduced tillage
- Residue management and cover crops
- Contour farming and terracing
- Strip cropping and grassed waterways
- Windbreaks and shelterbelts
- Conservation planning
Key theories
- Cover and management control of erosion
- Maintaining crop residue and living cover protects the soil surface from raindrop impact and wind, increases infiltration, and binds the soil, addressing the cover-and-management and support-practice factors that most strongly reduce soil loss.
- Integrated conservation planning
- Agronomic measures such as residue and cover crops, structural measures such as terraces and waterways, and biological measures such as windbreaks are combined to suit the slope, climate, and land use, since no single practice controls erosion everywhere.
Mechanisms
Surface residue and living cover intercept raindrops and wind, dissipating their energy and preventing detachment, while improving infiltration so less runoff is generated. Reduced tillage preserves residue and soil structure and limits the disturbance that exposes soil. Structural practices such as terraces, contour banks, and grassed waterways shorten and slow concentrated flow, reducing its erosive power, and windbreaks lower wind speed at the surface, cutting wind erosion. These measures are combined in conservation plans matched to local conditions.
Clinical relevance
Effective conservation practices preserve topsoil and its productivity, reduce off-site damage from sediment and nutrient pollution, and conserve water; analyses of the environmental and economic costs of erosion show that conservation generally yields large net benefits, underpinning conservation programs and policy.
History
Systematic soil conservation practice began after the Dust Bowl with the United States Soil Conservation Service, which promoted contouring, terracing, strip cropping, and residue management. The mid-century Universal Soil Loss Equation turned these into a quantitative planning system, and reduced and no-till systems spread widely from the late 20th century.
Key figures
- Hugh Hammond Bennett
- Walter H. Wischmeier
- David Pimentel
Related topics
Seminal works
- wischmeier1978
- pimentel1995
- brady2016
Frequently asked questions
- How does no-till farming reduce erosion?
- No-till leaves crop residue on the surface and avoids the soil disturbance of plowing, so the residue shields the soil from raindrop and wind energy, maintains soil structure and infiltration, and keeps the soil anchored, sharply reducing both water and wind erosion.
- What are cover crops and why are they used?
- Cover crops are plants grown primarily to protect and improve the soil rather than for harvest; by covering the ground between main crops they prevent erosion, add organic matter, scavenge nutrients, and improve structure and infiltration.