Microarthropods and leaf litter
Casandra Brocksmith, Colleen Conway, Lauren Gray, and Rachel Miller
Ecology class, BIO 342, Biology Department, DePauw University
Fall semester 2014
Microarthropods play an important role in regulating decomposition and mineralization processes in terrestrial ecosystems. The goal of our project was to assess the effects of soil water content and leaf litter on abundance of microarthropods. Leaf litter is defined as decomposing but recognizable leaves and other debris that form a layer on the soil. The amount of leaf litter is indicative of the amount of nutrients and organic matter present in the ecosystem. We focused on three types of microarthropods: (1) oribatids mites, a type of detritivore; (2) mesostigmatids and prostigmatids, two types of predators; and (3) springtails or collembola.
We hypothesized that microarthropods would be more abundant in areas with more leaf litter and higher soil water content.
We collected samples of soil and leaf litter from six locations on the W3 trail in the DePauw Nature Park. The six locations represented a gradient along a hillside; location 1 was at the top of the hill and location 6 was at the bottom of the hill in a flood zone. We collected 18 samples at each location. We used Berlese funnels in the lab to extract microarthropods from the samples. We used a dissecting scope to count the number of microarthropods in each sample. We dried and weighed the leaf litter and soil samples.
Soil water content increased from location 1 to location 6 and the amount of leaf litter decreased from location 1 to location 6. There was a significant relationship between the total number of microarthropods and the amount of leaf litter. As the amount of leaf litter increased, the abundance of microarthropods increased. Oribatid mites were most abundant at locations 1 through 5. Springtails were most abundant at location 6.