A Literary Review: The Interrelation of Soil Carbon, Moisture, Nutrients, and Microorganisms in Response to Clear Cutting
In North America, there has been growing concern on the impacts of deforestation on ecological communities, biodiversity, and currently climate change, where forest ecosystems are key buffers to global warming through the photosynthetic removal of carbon emissions (IPCC 2013). In Canada, with vast amounts of boreal forests, deforestation in the form of clear cutting is prominent in the forestry sector especially in Rocky Mountain Forest District spanning the provinces of British Columbia and Alberta. The viability of a forest is inevitably linked to the soil that sustains the ecosystem where the effects of clear cutting has been seen to range from beneficial to detrimental depending on soil properties and soil organisms.
Soil properties and soil organisms are intrinsically linked, thus clear cutting can physically alter the soil composition; the relative proportions of sand, silt, and clay particles (Gurevitch et al. 2006) through the compaction, overturn, erosion, and/or exposure consequently causing changes in other properties such as soil organic carbon content, moisture content, and nutrient content. The changes in the chemical and physical properties of soil then impact soil organisms such as bacteria and fungi, consequently having effects that echo through the food web on plants and invertebrates.
Soil organic carbon content is controlled by various processes but is highly dependent on the microbial communities through soil respiration. Harvesting forest biomass can expose the soil to greater detriment deposition that shifts the microbial community composition (Nave et al. 2010), lowering the overall organic carbon content by releasing it into the atmosphere due to increased microbial activity. On the contrary, in certain clear cut areas, the significant reduction of vegetation that provides accessible carbon to the microorganisms may lower the rates of soil respiration instead causing an accumulation of organic carbon in the soil (Churchland et al. 2013). Changing the organic soil carbon can also alter C:N ratios as well affecting the composition of microbial communities, where soils with high C:N ratios tend to be composed of fungi and alternatively, soils with low C:N ratios tend to be composed of bacteria (Bardgett and Wardle 2010). Biological processes heavily dominate the organic carbon content in forest soils by either retaining or releasing carbon rendering it a growing issue in forest management.
Microbial respiration is regulated by soil moisture as well as water is vital in the process of respiration (Liu et al. 2008). Various effects on soil moisture arise due to clear cutting depending on the amount of time the forest biomass was removed, the amount of regrowth, and the type of regrowth that regenerates the area. Initially, the soil moisture may be higher after a clear cut due to the lack of...