In minimum tillage specialized tillage and planting equipment are used so that only part of the soil surface is disturbed. One specific example of minimum tillage would be ridge till, in which inch centimeters ridges are formed in the soil. The crop is seeded in the ridges, leaving much of the surrounding soil relatively undisturbed. In addition to using conservation tillage to establish forage stands, there are other steps forage producers can take to minimize soil erosion. Planting windbreaks will help reduce wind erosion.
Some studies have suggested that the reduction in wind speed may be effective as far as 15 times the height of the trees. Steps to minimize water erosion would include reducing the effective steepness and length of slopes through the construction of terraces.
Reducing the velocity of water moving across the soil surface will reduce water erosion. This may be accomplished by using strip cropping. In strip cropping a row crop such as corn is planted in strips that alternate with strips of a forage crop such as alfalfa or grass hay. Another way to reduce the velocity of water moving across the soil is to plant and cultivate crops parallel to the natural slope or contours of the land.
This technique known as contour tillage, may sometimes be combined with strip cropping and is known as contour strip-cropping. Hay cuttings should be timed to maintain a healthy productive forage stand. A stand weakened through improper cutting management may begin to thin out, leaving areas of soil not well covered by vegetation.
This result is a subtle, gradual increase in soil erosion. Similarly, overgrazing pastures or rangeland leaves areas of soil unprotected by vegetation which leads to greater levels of water and wind erosion.
In forage production, it is almost inevitable that some soil erosion will occur, despite the best efforts to combat it. Nevertheless, responsible forage producers will take appropriate steps to maintain a healthy vegetative cover to protect soil against excessive erosion. This will require appropriate use of conservation tillage techniques, timing hay harvest to maintain healthy stands, and careful management of grazing animals to avoid overgrazing.
Skip to main content. Toggle menu Go to search page. Search Field. Explain how forages have been and are essential to civilization. Summarize the history of forages. Define grassland agriculture. Discuss a typical grassland ecosystem. Define sustainable agriculture and discuss how forages are a key component.
List several grassland organizations and describe their role in promoting forages and grassland agriculture. Locate and describe the tropical grasslands and their forages. Locate and describe the temperate grasslands and their forages. Important issues affecting grasslands and their forages.
Describe the current role of forages in US agriculture. Discuss regional forage production. Discuss forages from a livestock perspective. Discuss the environmental benefits of forages. Discuss the possible future role of forages in the US.
Differentiate warm-season from cool-season grasses. Summarize the distinctive physical characteristics of grasses Describe the utilization of grass in forage-livestock systems. Describe how knowledge of grass regrowth is beneficial to forage managers. Provide specific information about the common grasses used as forage Summary Exam References Legumes Overview Pretest - Legumes Instructional Objectives Legumes are a valuable part of forage production. Differentiate warm-season from cool-season legumes.
Summarize the distinctive physical characteristics of legumes. Define the utilization of legumes in forage-livestock systems. The loose topsoil is then transported by wind to nearby streams and waterways and become sediment or runoff, lowering the overall quality of the water. Types of Soil Degradation. When is the Moon's Pull on Earth the Strongest? How the Atmosphere Protects the Earth. The Effects of Soil Erosion. What Are the Causes of the Destruction of Ecosystem?
Negative Effects of Pollution. How Are River Rocks Formed? Wilkinson will present his findings Nov. Many researchers have tried to assess the impact of human activity on soil loss, but most have only guessed at how erosion due to natural forces such as glaciers and rivers compares with that caused by human activitymainly agriculture and construction, Wilkinson said.
He used existing data on sedimentary rock distributions and abundances to calculate rates of natural erosion. In those parts of the United States where soil is being eroded by human agricultural activity, however, the rate averages around 1, feet per million years, and rates are even higher in other parts of the world. Natural processes operate over areas larger than those affected by agriculture and construction, but even taking that into account, "the bottom line is, we move about 10 times as much sediment as all natural processes put together," he said.
Because soil formation proceeds at about the same rate as natural erosion, Wilkinson's results mean that humans are stripping soil from the surface of the Earth far faster than nature can replace it.
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