Soil science is the study of soil as a natural resource on the surface of the Earth including soil formation, classification and mapping; physical, chemical, biological, and fertility properties of soils; and these properties in relation to the use and management of soils.
Some soil scientists are involved in the daily activities of food production. They test the soil in which the crops are grown and make fertilizer recommendations, as well as managing irrigation scheduling in regions where irrigation is practiced. They also work to conserve the soil resources, developing methods to protect the soil from wind and water erosion. In dryland regions, soil scientists help develop management systems (tillage and crops) that store rainfall in the soil for future crops.
Soil classification deals with the systematic categorization of soils based on distinguishing characteristics as well as criteria that dictate choices in use.
Pediatrician translates to "physician for children" which at least makes some sense. A "pediologist" would be an "expert on children".
I get to travel all over the USA and to foreign countries (Canada, Mexico, Japan, China, and counting) to study soil (play in the dirt there, too). I am an associate professor at a university, so my main responsibilities include teaching college students and doing research. I enjoy the lab activities most because we go outside and work with and/or in the soil.
One of the other really fun things I do is meet with school children, usually fourth or fifth graders, and talk about why soil is important to their lives (food, clothes, etc.), and to the environment. I am what I want to be when I grow up - in other words, I enjoy my job.
Agronomy is the science and technology of producing and using plants for food, fuel, fiber, and land reclamation. Agronomy has come to encompass work in the areas of plant genetics, plant physiology, meteorology, and soil science. It is the application of a combination of sciences like biology, chemistry, economics, ecology, earth science, and genetics. Agronomists of today are involved with many issues, including producing food, creating healthier food, managing the environmental impact of agriculture, and extracting energy from plants. Agronomists often specialise in areas such as crop rotation, irrigation and drainage, plant breeding, plant physiology, soil classification, soil fertility, weed control, and insect and pest control.
I am not sure what the average salary of a soil scientist is, as that probably depends a lot upon the region of the country in which they live. Most beginning soil scientists would probably start with a salary of about $30,000 (give or take $4,000) for regional differences in the USA.
Soil is only found on the earth's surface. The depth of a soil depends mostly on how much rain falls on the soil, and how old the soil is. Some soils are only a few inches (or centimeters) thick - on mountains, in some deserts, and in arctic regions. Other soils can be more than 6' feet (two meters) deep. Though sometimes soils are deeper, we usually do not consider them as soil because roots of most plants are concentrated in the top 2 or 3 meters. Topsoil is usually the top 15 to 30 centimeters of soil. The subsoil then may go down to 2 or 3 meters.
Pedogenesis also termed soil development, soil evolution, soil formation, and soil genesis is the process of soil formation as regulated by the effects of place, environment, and history. Biogeochemical processes act to both create and destroy order (anisotropy) within soils. These alterations lead to the development of layers, termed soil horizons, distinguished by differences in color, structure, texture, and chemistry. These features occur in patterns of soil type distribution, forming in response to differences in soil forming factors.
No one is old enough to have observed how long it took to form a foot of soil. With the right conditions, a foot of topsoil may form in less than one hundred (100) years. These conditions would include a fresh deposit of loose material (as might happen during or after a flood) in which the soil could form, a stable landscape position so that soil formation is not interrupted, and a favorable climate that encourages the growth of grass (plants with fibrous root systems form topsoil faster than trees with taproots). When the original material is bedrock, like sandstone or limestone, that must first weather into small particles before the soil can form, and the process is much slower.