Study of Earth
Study of Earth
The Earth is comprised of four major subsystems; The Geosphere, Biosphere, Atmosphere and the Hydrosphere. The Geosphere is the solid earth as a whole. The biosphere contains all living and recently dead organisms on earth. The Atmosphere is the envelope of gases that surround the earth and the hydrosphere is the system that contains all of the Earths bodies of water and ice, both on the surface and underground.
The subsystems all work together to provide the earth with everything that we need to survive. Plants draw nutrients from the lithosphere (the earth’s rocky outermost layer) and incorporate them into the biosphere; when they die and decompose. The material that they contain may enter the atmosphere, or return to the geosphere. Rocks erode, and the minerals that they contain become salts in the hydrosphere; evaporation returns these salts to the geosphere. The exchanges of materials between the different spheres never stop.
The biosphere is the space on and near the Earth's surface that contains and supports living organisms and ecosystems. The biosphere is our environment. It contains everything that we need to survive. It contains air so that we can breathe and water so that we can drink; it contains fertile soil so that we can grow food.
The geosphere is also known as the lithosphere. It consists of the solid part of the earth, the crust and the outer mantle. Basically the main resource in this system is the ground that we walk on. Hills, mountains and other physical land masses would also be contained in this system. Obviously we need this subsystem to live. Without the crust this planet would be uninhabitable.
The atmosphere is a mixture of nitrogen (78%), oxygen (21%), and other gases (1%) that surrounds Earth. High above the planet, the atmosphere becomes thinner until it gradually reaches space. It is divided into five layers. Most of the weather and clouds are found in the first layer. The...