Impact of Fire on the Geology of Soils Essay

2669 Words 11 Pages
Fires are an important and healthy process in many ecosystems. The lack of fires can cause new plant communities to invade an area . The regular occurrence of fires can keep one plant community dominate, like oak savannas. Fires can leave burnt sticks the size of trees and clumps of charcoal where bunch grass use to grow, but not for long. An area that was burned will re-grow, grasslands will be green the next growing season and forests will typically show new growth soon after. Somewhere in the process of a fire the soil it travels over is effected. Alterations happen immediately after a fire passes over a soil and can continue years after a fire has gone. Soils are impacted in two main ways; by the entering of nutrients form the brunt …show more content…
The differences between the two may effect how the alterations of soil are disturbed, but both will undergo the same general processes.

The heat of a fire has many effects on the properties of a soil. The effects are not the same for every soil type because it depends on what is present in the soil before the fire. In my paper, I will be exploring different types of alterations a soil may undergo as a result of a fire. The three main areas I am going to look at are; change in color and structure, hydrophobic properties after a fire, and the alteration in nutrient cycles, in particular nitrogen. In conjunction with what changes occur to the properties of a soil, I will also be looking at management practices that can lessen the undesirable changes in soil.

Effects on soil color and structure

In heating most substances, change in color and texture or structure occurs, this generally holds true in the case of soils. A. L. Ulery and R. C. Graham (1993) did a study on how fire alters both color and texture of soils. The color of the burned soils tended to redden in hue and have higher chromas and values after burning, than did the unburned soil of the same type (Ulery and Graham, 1993). One reason that the color changed is most likely due to the translocation and transformation of nutrients and minerals in the soil. As the soil burns the heat alters individual minerals in the soil. The redder color in the soil was caused by an