4 Soil Erosion and Conservation Free Online FlashCards

What is soil erosion?

Soil erosion is the detachment and movement of soil by water, wind, or tillage.

What conditions make soil more vulnerable to water or wind erosion?

Intense rainfall, runoff, long or steep slopes, and slowly absorbing soil increase water erosion risk. Dry, loose, bare soil and strong winds favor wind erosion.

How does splash erosion occur?

Raindrops strike bare soil and dislodge particles, which may then be moved by runoff.

What are the three ways wind moves soil particles?

Wind moves fine particles by suspension, bouncing particles by saltation, and larger particles rolling or sliding by surface creep.

How can topsoil loss affect land productivity?

Erosion removes topsoil, which commonly contains much of a soil’s organic matter and nutrients. This can reduce soil depth, water-holding capacity, fertility, and crop productivity.

How does keeping soil covered help prevent erosion?

Vegetation, cover crops, grasses, and retained crop residues shield soil from raindrop impact and wind. Roots also help bind soil and support its structure.

How does contour farming reduce water erosion?

Contour farming follows the natural contours of a slope, slowing water as it moves downhill.

How does conservation tillage protect soil?

Reduced-till and no-till systems disturb soil less and leave more residue on the surface, helping protect it from erosion.

How can human activities increase erosion risk?

Clearing vegetation, overgrazing, intensive tillage, and construction can remove protective cover or disturb soil structure, increasing erosion risk.

What distinguishes sheet erosion?

Runoff removes a thin, relatively even layer of soil across a broad area. Because the loss can be hard to see, it may go unnoticed for years.

What is rill erosion?

Rill erosion occurs when flowing water concentrates into small channels. Ordinary field operations can often smooth the channels.

What makes gully erosion different from rill erosion?

Gully erosion forms larger, deeper channels from concentrated runoff. Normal tillage cannot readily remove gullies, which can expand and carry substantial sediment downhill.