Lantana invasion alters soil nitrogen pools and processes in the tropical dry deciduous forest of India

Abstract

Invasive species can alter the soil nutrient pools and processes in ecosystems that they invade by altering the quality and quantity of litter inputs. Studies have shown the impact of vegetative understory invasions on soil nitrogen (N) availability in forest ecosystems. In the dry deciduous Vindhyan forest of India we studied the effect of one of the world’s most noxious weeds, lantana (Lantana camara L.) on soil N availability and N-mineralization beneath the forest canopy and lantana canopy. We observed that the lantana litter inputs increase with increasing lantana cover and the chemical composition of lantana litter was also very much different from the native forest species litter. High N, low lignin content of the lantana litter and favorable microclimate beneath lantana canopy favored faster decomposition and release of N. This alteration in litter inputs and chemistry beneath the lantana canopy positively and significantly altered soil N availability, N-mineralization, and total soil N. The results imply that a positive feed back nutrient cycle might exist beneath the lantana canopy which may favor its growth (cover) by increasing the nutrients beneath its canopy.