Erosion and Soils

The first interesting geographic concept talks about soil components. Notably, it takes a long period of time for soil characteristic to develop through a variety of processes acting in unison. As Strahler (2006) explains, the usual soil comprises of 50% organic material and mineral, and the other half open pores full of water and air.

Certain physical processes crush down rock particles into even smaller pieces. Chemical processes then change the mineral composition of the parent rock material, or sediment, and end in new minerals. A number of things including plant roots, invertebrates and microbes mix and compost organic material and minerals into a novel matrix of soil.

According to Strahler (2006), together these chemical, physical and biological processes are known as weathering. Such weathering processes, after a while, soften, fragment, and crush bedrock apart, thus forming a layer known as ‘regolith’ (Strahler, 2006). Other types of regolith include mineral particles transported by glaciers, streams, water currents, waves and winds. More often than not, the top layer of regolith weathers and forms soil. Thus, soil includes mineral from plants, vertebrate and invertebrate animals, microorganisms and rock material. As Strahler (2006) stipulates, some ‘humus’gets carried deep into the soil while some rests on the soil.

The second concept, I found interesting, touches on soil properties. Notably, soil can be categorized using properties as structure, color, texture and moisture. Color is the most palpable characteristic. While some soils are dark brown or black, others might be yellow or red. The color comes about during the process of soil formation. Soil structure, as Strahler (2006) stipulates, is the way in which soil grains clump together to form large masses referred to as ‘peds’, which range from small to large grains. Soils that have a well-developed blocky or granular structure can be easily cultivated. According to Strahler (2006), this factor can sustain the non-mechanized type of farming. Soil moisture is also another characteristic that defines soil. It determines how the soils of a certain region will support crops and general vegetation.