The effect of non-native earthworms on northern Michigan soils.

Abstract

Earthworms are a non-native species in northern Michigan and their impact on soil structure and ecosystem dynamics is still poorly understood. Alterations in the proportions of nitrogen and carbon in the soil affect primary production, which in turn has consequences for higher trophic levels. Our research investigated the effect of non-native earthworms on carbon and nitrogen in soils of northern Michigan by conducting one manipulative experiment in two soil types and one observational experiment. Our results showed that the total nitrogen and carbon in anecic earthworm burrows was positively correlated with the total values in non-burrows. Also, the earthworms significantly decreased carbon levels in sandy outwash plain soil rather than nutrient rich moraine soil and had negligible effects on nitrogen in both soils. Non-native earthworms catalyze the release of carbon into the atmosphere in outwash plains, therefore, negatively affecting the forest ecosystems. Concurrent with leading research, non-native earthworms stand to be invasive species.