Death due to disease is called death by natural causes. There are four main types of disease: pathogenic disease, deficiency disease, hereditary disease, and physiological disease. Diseases can also be classified as communicable and non-communicable disease.
A watershed is the area of land where all of the water that falls in it and drains off of it goes to a common outlet.
A watershed is the area of land that drains into a body of water such as a river, lake, stream or bay. It is separated from other systems by high points in the area such as hills or slopes.It includes not only the waterway itself but also the entire land area that drains to it.ow the land in a watershed is used by people, whether it is farms, houses or shopping centers, has a direct impact on the water quality of the watershed. When it rains, stormwater carries with it the effects of human activities as it drains off the land into the local waterway.