Overgrazing is a significant cause of degradation of grassland in the United States. Why is overgrazing so devastating to grassland? Why would the people who control grazing allow overgrazing to happen, given what we know about the problems associated with it?
What will be an ideal response?
Overgrazing removes not only the upper part of the grass plant, it also kills the root system and growing region of the plant. Grasslands are relatively dry, with water being one of the limiting resources (a primary reason there are no trees). When the entire grass plant is killed, the root system cannot hold the soil and the soil is eroded and dried out by the wind. With the soil dry and eroded, the grassland is severely degraded and becomes more like desert. There are many reasons this may be allowed to happen,such as ignorance of the sequence of events or consequences, preoccupation with turning a profit, and negligence.
You might also like to view...
During the last century, sea level
A) dropped 3 to 5 cm (1.18 to 3.15 in.). B) remained fairly constant, though some areas (such at the Atlantic coast) experienced moderate rises. C) rose 30 to 46 cm (11.8 to 18 in.). D) rose 17 to 21 cm (6.7 to 8.3 in.).
Most material eroded from a coastal cliff ends up as a ________.
A) terrace B) notch C) beach D) spit E) none of the above
Stability of earth materials on slopes depends on the balance of gravitational and frictional forces. Which of the following does NOT have a measurable effect on the balance between gravity and friction?
A. presence of water B. steepness of a slope C. atmospheric air pressure D. types of vegetation on the slope E. type of rock or sediment that is making up the slope
Species that are found only in specific environments or have restricted localities are said to be ________
A) evenness B) diverse C) endemic D) rich E) structurally complex