Main Natural Resources
By H. Sudiyono
MAIN NATURAL RESOURCES
A natural resource is anything people can use which comes from nature. People do not make natural resources, but gather them from the earth. To know further about some main natural resources, here will be provided some of them ; i.e. air, water, and wind energy.
Air, (as E.F. Darley and J.T. Middleton) said, is an important natural resources, vital to animals and plants. The major chemical constituents of air at the earth’s surface are primarily nitrogen, 78 per cent, and oxygen, 21 per cent, while the minor constituents are carbon dioxide, water vapor, and a variety of other compounds amounting to 1 per cent. Air has many uses. Some of them are as follows: (1) Air contains oxygen, which is essential for life. All living things respire by breathing in air. The air we breathe in is inhaled air. The air we breathe out is exhaled air. (2) Air supports burning or combustion. The oxygen present in air is essential for burning. We burn fuels to cook food, generate heat and electricity, run industries and drive vehicles. The presence of nitrogen reduces the activity of oxygen. If air contained mostly oxygen, even small fires would turn into huge explosions! (3) The nitrogen present in air is essential for the growth of plants. Plants take in nitrogen directly from the air or from the soil. (4) A layer of ozone gas present high up in the atmosphere protects us from the harmful ultraviolet rays of the sun. Also during daytime, the atmosphere prevents excessive heat from the sun from reaching us. At night, the atmosphere traps the surface heat and prevents it from escaping. (5) Moving air, called wind, has great force. It enables the movement of sailboats and gliders. It runs windmills, which are used to generate electricity. Wind also helps in the dispersal of seeds. (6) Compressed air is used in a number of ways. It is used to fill tyres. Many machines make use of compressed air. For example, machines used in mining and digging and the drill used by dentists work on compressed air. (7) Carbon dioxide is taken from air by plants for photosynthesis, the process of making their food. The air we breathe out contains carbon dioxide. Exhaled air can be tested for the presence of carbon dioxide.
Water is a chemical compound with the chemical formula H
2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at standard ambient temperature and pressure, but it often co-exists on Earth with its solid state, ice, and gaseous state, steam (water vapor). Water also exists in a liquid crystal state near hydrophilic surfaces. Water covers 71% of the Earth’s surface and is vital for all known forms of life. On Earth, 96.5% of the planet’s water is found in seas and oceans, 1.7% in groundwater, 1.7% in glaciers and the ice caps of Antarctica and Greenland, a small fraction in other large water bodies, and 0.001% in the air as vapor, clouds (formed of solid and liquid water particles suspended in air), and precipitation. Only 2.5% of the Earth’s water is freshwater, and 98.8% of that water is in ice and groundwater. Less than 0.3% of all freshwater is in rivers, lakes, and the atmosphere, and an even smaller amount of the Earth’s freshwater (0.003%) is contained within biological bodies and manufactured products. Water on Earth moves continually through the water cycle of evaporation and transpiration (evapotranspiration), condensation, precipitation, and runoff, usually reaching the sea. Evaporation and transpiration contribute to the precipitation over land. Safe drinking water is essential to humans and other life forms even though it provides no calories or organic nutrients. Water plays an important role in the world economy, as it functions as a solvent for a wide variety of chemical substances and facilitates industrial cooling and transportation. Approximately 70% of the fresh water used by humans goes to agriculture.
Wind power is the conversion of wind energy into a useful form of energy, such as using wind turbines to make electrical power, windmills for mechanical power, wind pumps for water pumping or drainage, or sails to propel ships. Large wind farms consist of hundreds of individual wind turbines which are connected to the electric power transmission network. For new constructions, onshore wind is an inexpensive source of electricity, competitive with or in many places cheaper than fossil fuel plants. Small onshore wind farms provide electricity to isolated locations. Utility companies increasingly buy surplus electricity produced by small domestic wind turbines. Offshore wind is steadier and stronger than on land, and offshore farms have less visual impact, but construction and maintenance costs are considerably higher. Wind power, as an alternative to fossil fuels, is plentiful, renewable, widely distributed, clean, produces no greenhouse gas emissions during operation and uses little land. The effects on the environment are generally less problematic than those from other power sources. As of 2011, Denmark is generating more than a quarter of its electricity from wind and 83 countries around the world are using wind power to supply the electricity grid. In 2010 wind energy production was over 2.5% of total worldwide electricity usage, and growing rapidly at more than 25% per annum. Wind power is very consistent from year to year but has significant variation over shorter time scales. As the proportion of wind power in a region increases, a need to upgrade the grid, and a lowered ability to supplant conventional production can occur. Power management techniques such as having excess capacity storage, geographically distributed turbines, dispatch able backing sources, storage such as pumped-storage hydroelectricity, exporting and importing power to neighboring areas or reducing demand when wind production is low, can greatly mitigate these problems. In addition, weather forecasting permits the electricity network to be readied for the predictable variations in production that occur.
Sources/adopted from : Wikipedia.org