The body of the soil is formed from a mixture of organic and mineral materials. Non-organic soil or mineral soil is formed from rocks so that it contains minerals. In contrast, organic soils are formed by compaction of degraded organic matter.
Organic soil has a dark (black) color and is the main form of peatland. This organic land will continue to undergo a long process for hundreds of years to become coal.
Organic soils tend to have high acidity because they contain some organic acids as a result of decomposition of various organic materials. This land usually has a low mineral content. Mineral supply that can be obtained by organilk soil, which comes from the flow of water or the result of decomposition of tissue of living things. Organic soil can be planted because it has loose physical properties so that it can store enough water. However, because it has high acidity, most plants that use this media cannot grow optimally.
Non-organic soils are dominated by minerals. These minerals form particles of soil forming. Soil texture is determined by the composition of three soil-forming particles: sand, lakes (dust), and clay.
In terms of color, the soil has a variety of colors that are very diverse ranging from dark black, brown, brick red, orange, yellow, to white. In addition, the soil also has very contrasting color differences on each layer as a result of chemical processes.
Soil that has a dark color is a characteristic that usually indicates that the soil contains high levels of organic matter. Dark colors can also be caused by the presence of manganese, sulfur and nitrogen. Reddish or yellowish soil colors are usually caused by high oxidized iron content; different colors occur due to the effects of the chemical process conditions of their formation.
The aerobic / oxidative atmosphere produces uniform colors or gradual discoloration, while the anaerobic / reductive atmosphere leads to a color pattern that resembles concentrated spots or colors.