Invasive plants accelerate nitrogen cycling: evidence from experimental woody monocultures
Jo, I., J.D. Fridley and D.A. Frank. 2017.
Abstract
Summary
1. Although it is widely believed that non-native invasive species threaten the functional integrity of
forest ecosystems, their impact on important ecosystem processes such as nitrogen (N) cycling is
not well understood.
2. To examine how invasive species alter ecosystem N dynamics, we established monocultures of
five phylogenetic pairs of native and non-native invasive understory woody species common to East-
ern U.S. forests.
3. After 3 years, we found invaders increased N cycling by enhancing the flow of N to the soil
through greater litter N production and litter N content, and increased the uptake of available soil N,
via greater fine root production and specific root length.
4. Synthesis. Our results highlight the importance of linking above- and below-ground processes to
better understand invader impacts on ecosystem nutrient processes. The rapid shifts in soil N pro-
cesses as a result of invader dominance observed in our study suggest that invaders may be an
important driver of forest ecosystem functioning.
Key Words
Eastern United States, inorganic nitrogen pool, monoculture experiment, nitrogen cycling, plant invasions, plant-soil feedback, understory woody species
