Renewable resources may be defined as resources that have the potential to be replaced over time by natural processes. The renewal process may be relatively quick, as with sunshine which comes on a daily basis.
Or, the renewal process may be very slow, as in the formation of soil which may take hundreds of years. Nonrenewable resources may be defined as resources whose stock or reserves is limited or fixed. The available supply of nonrenewable resources may be replenished through recycling e.
The table below gives several examples of each type of resource. Examining the resources listed in the table above suggests that modern agricultural production, including forage production, is dependent on a number of resources that are considered nonrenewable.
Farm equipment contains steel and aluminum parts and uses oil based fuels. The energy to manufacture fertilizer and other agrichemicals is derived from oil, coal, and natural gas. Phosphate fertilizers are widely used on crops. The realization of this dependence on nonrenewable resources has led to increased interest in developing and implementing so called sustainable agricultural production systems, as will be discussed in other sections of this lecture topic.
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. Definition: A non-renewable resource is a natural resource that cannot be replenished by nature as quick as it is consumed. It is an element whose reserves will be depleted at some point and it will not be possible to get any more of it in the mid-term. Some of these non renewables are fossil fuels like oil, coal and natural gas or minerals like gold, silver and iron.
Many companies exploit nonrenewable resources causing countries impose specific taxes to such businesses, since the non renewable nature of these resources makes them very valuable for the country and these special tariffs ensure the nation benefits from the operation.
Non-renewable energy comes from sources that will run out or will not be replenish ed in our lifetimes—or even in many, many lifetimes. Most non-renewable energy sources are fossil fuel s: coal, petroleum, and natural gas. Carbon is the main element in fossil fuels. For this reason, the time period that fossil fuels formed about million years ago is called the Carboniferous Period. All fossil fuels formed in a similar way. Hundreds of millions of years ago, even before the dinosaurs, Earth had a different landscape.
It was covered with wide, shallow seas and swampy forests. Plants, algae , and plankton grew in these ancient wetland s. They absorbed sunlight and created energy through photosynthesis.
When they died, the organisms drifted to the bottom of the sea or lake. There was energy stored in the plants and animals when they died. Over time, the dead plants were crushed under the seabed. Rocks and other sediment piled on top of them, creating high heat and pressure underground. In this environment, the plant and animal remains eventually turned into fossil fuels coal, natural gas, and petroleum.
Today, there are huge underground pockets called reservoir s of these non-renewable sources of energy all over the world. Fossil fuels are a valuable source of energy. They are relatively inexpensive to extract. They can also be stored, piped, or shipped anywhere in the world. However, burning fossil fuels is harmful for the environment.
When coal and oil are burned, they release particles that can pollute the air, water, and land. Some of these particles are caught and set aside, but many of them are released into the air. When fossil fuels are combust ed heated , they release carbon dioxide into the atmosphere. The carbon in fossil fuels has been sequester ed, or stored, underground for millions of years. This contributes to temperatures rising faster than organisms can adapt.
Coal is a black or brownish rock. We burn coal to create energy. Carbonization is the process that ancient organisms undergo to become coal. About 3 meters 10 feet of solid vegetation crushed together into. Peat is the lowest rank of coal. It has gone through the least amount of carbonization. It is an important fuel in areas of the world including Scotland, Ireland, and Finland.
Anthracite is the highest rank of coal. Anthracite forms in regions of the world where there have been giant movements of the earth, such as the formation of mountain ranges. The Appalachian Mountains, in the eastern part of the United States, are rich in anthracite. We mine coal out of the ground so we can burn it for energy. There are two ways that we can mine coal: underground mining and surface mining. Miners take an elevator down a mineshaft. They operate heavy machinery that cuts the coal out of the Earth and brings it above ground.
This can be dangerous work because cutting coal can release dangerous gases. The gases can cause explosions or make it hard for miners to breathe. Surface mining is used when the coal is located very near the surface of the earth. To get to the coal, companies must first clear the area. They take away the trees and soil. The coal can then be cut out of the ground more easily. Entire habitat s are destroyed during this process. About half the electricity in the United States comes from coal.
It gives power to our lights, refrigerators, dishwashers, and most other things we plug in. We use the byproducts to make cement, plastics, roads, and many other things. Coal is a reliable source of energy. We can rely on it day and night, summer and winter, sunshine or rain, to provide fuel and electricity. Using coal is also harmful. Mining is one of the most dangerous jobs in the world. Coal miners are exposed to toxic dust and face the dangers of cave-ins and explosions at work.
When coal is burned, it releases many toxic gases and pollutant s into the atmosphere. Mining for coal can also cause the ground to cave in and create underground fires that burn for decades at a time. Petroleum is a liquid fossil fuel. It is also called oil or crude oil. Petroleum is trapped by underground rock formations. In some places, oil bubbles right out of the ground.
Remains of animals that got trapped there thousands of years ago are still preserved in the tar! We drill through the earth to access the oil. Some deposits are on land, and others are under the ocean floor. Many successful oil sites produce oil for about 30 years.
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