Understanding Soils in Forests

Written by Sabrina Kleinman

Soil is an important component of forest and woodland ecosystems as it helps regulate important ecosystem processes, such as nutrient uptake, decomposition, and water availability. Soil also represents one of the largest carbon pools on the planet whose alteration can impact carbon storage and carbon emissions. Soil carbon helps soils retain water, increases soil’s capacity for holding on to important nutrients such as nitrogen and phosphorous, and serves as a source of energy for belowground organisms such as insects and fungi. How landowners maintain and cultivate healthy soils can affect the success of treatments used to address climate change.

Figure 1. A photo of a soil profile in Alabama.
Licensed under Creation Attributions 3.0
USDA Forest Service, Pineville Archive

Many of the important functions of soil are altered when environmental changes occur. These changes can dramatically affect the overall productivity of a forest. For example, increased temperature has been shown to increase microbial respiration in soils, elevating nutrient turnover and allowing for increased short-term carbon storage in trees and increased soil respiration (Melillo et al. 2002). However, decreased water availability from drought can limit carbon turnover, reducing carbon storage in trees and increasing carbon emissions from soils (Borken et al. 2006). Understanding the role and function of soils can inform our understanding of how changes in climate can impact the overall health and long-term success of forest ecosystems in light of a changing environment.

To understand Forest Soils:

• Basic Soil Components
• Dynamics of Nutrient Cycling
• Understanding Decomposition and Its Controls
• Soils and Water Availability

References Cited
Melillo J.M., P.A. Steudler, J.D. Aber, K. Newkirk, H. Lux, F.P. Bowles, C. Catricala, A. Magill, T. Ahrens, S. Morrisseau. 2002 Soil warming and carbon-cycle feedbacks to climate system. Nature. 298: 2173-2176.

Borken W., K. Savage, E.A. Davidson, and S.E. Trumbore. 2006. Effects of experimental drought on soil respiration and radiocarbon efflux from a temperature forest soil. Global Change Biology. 12: 177-193.