Spatial analysis of Lumbricus spp. distribution in West Liberty University's campus woods.

Naturalized earthworms of the genus Lumbricus are not commonly found in deciduous hardwood forests of North America but have been expanding into these areas in recent years. This is a problem because Lumbricus worms consume large amounts of leaf litter, disturbing natural soil horizons. The disruption results in damage to native plant life, seedlings specifically, by depleting the forest floor and draining nutrients necessary for growth. A monitoring project established in 2020 surveys a 900 m2 plot in WLU's campus woods community known to be inhabited by lumbricid earthworms. Weekly data collection of the area measures worm density, length, and a variety of environmental parameters. In 2023, the distribution of Lumbricus spp., in patches and gaps, was determined using the statistical method SADIE (Spatial Analysis by Distances IndicEs). Earthworm aggregations, or patches, were found to be significant in several locations. A comparison between data from 2022 and 2023 showed that while significant patches were present each year, the overall area of patches was more significant in 2023. However, the data did not show a significant spatial association of patches when comparing patch locations between the two seasons. The data indicates that the worms' range expanded, and patch locations shifted from 2022 to 2023. Additionally, while both populations endured drought conditions, a 100% increase in worm density was seen in 2023. Further observation is needed to understand and assess the full impact of Lumbricus spp. population and spatial dynamics in forested areas. [ABSTRACT FROM AUTHOR]