Terrestrial vs. Aquatic Leaf Litter Decomposition Rates

Leaf litter is defined as deceased plant material that has fallen to the ground. This dead organic material, known as leaf litter, and its constituent nutrients are an addition to the top layer of soil, which is known as the litter layer. Decomposition provides readily available nutrients to plants, incorporating organic carbon into soil through nutrient cycling processes. This semester, a group of student experiments were used to study the impacts of various environmental factors on leaf litter decomposition. Every group deployed their experimental leaf litter bags in either an aquatic habitat or a terrestrial habitat for a period of 5 weeks. Students prepped, launched, and processed their own leaf litter bags for the experimental study. In the study, the students used mesh bags to hold 25 g of leaves and left the bags in the field for a total of five weeks. At the conclusion of the field period, students processed their leaf bags, dried the leaves, and re-weighed them to calculate a final decomposition rate (i.e., mass loss per day). I performed calculations on the student datasets in a meta-analysis to measure whether there was an overall difference in aquatic versus terrestrial decomposition rates across student trials. The results of my meta-analysis demonstrated that the aquatic habitat had higher leaf litter decomposition rates than the terrestrial habitat. My hypothesis was accepted as I found that the aquatic habitat had higher leaf litter decomposition rates than the terrestrial habitat. Potential future studies that could be addressed from the student experiments could include an in-depth analysis on the factors that went into the aquatic habitat having higher decomposition rates than the terrestrial habitat. Several factors can influence the decomposition rate of leaf litter. Factors such as the presence of water, light levels, and biological activity should be considered.