What are the four main natural resources in the united states?
and what does silt do to help farmland?
Water, fertile soil, lots of land, and oil. You could also include favorable climate and coal.
http://www.photius.com/wfb1999/united_states/united_states_geography.html
The four main natural resources in the United States are:
1. Petroleum: The U.S. is one of the world's largest producers and consumers of petroleum, which is used for various purposes, including transportation, heating, and electricity generation.
2. Natural gas: The U.S. has abundant reserves of natural gas, which is primarily used for electricity generation, industrial processes, and heating.
3. Coal: The United States has significant coal reserves and is one of the largest producers and consumers of coal in the world. Coal is mainly used for electricity generation and in industrial processes.
4. Timber: The U.S. is rich in forests and has a large timber industry. Timber is used for various purposes, including construction, furniture manufacturing, and paper production.
Regarding your second question, silt plays a crucial role in helping farmland. Silt is a granular material made up of very fine particles, typically found in riverbeds or floodplains. When rivers flood, they deposit silt onto nearby agricultural land. This process is known as siltation.
Here's how silt helps farmland:
1. Fertility: Silt is rich in minerals and organic matter, which makes it highly fertile. When silt gets deposited on farmland, it adds nutrients to the soil and improves its overall fertility.
2. Water Retention: Silt has small particle sizes that help in water retention. It can hold water and nutrients within its particles, making it available to plant roots. This property is essential for crop growth, especially in areas with limited water supply.
3. Drainage: Silt has good drainage properties, which means it allows excess water to drain away while still retaining enough moisture for plant growth. Adequate drainage prevents waterlogging and ensures that plant roots have access to oxygen.
4. Soil Structure: Silt particles have a smooth texture, which aids in improving soil structure. It helps bind soil particles together and creates a well-structured soil that is loose and fertile, allowing roots to penetrate easily.
In summary, silt helps farmland by adding fertility, improving water retention and drainage, and enhancing soil structure.