Modelling the invasion, management strategies and economic impact of the invasive alien aquatic plant Egeria densa

Abstract

Egeria densa is a south American aquatic plant considered as an invasive alien species with a very aggressive and expansionist behaviour out of its native ecosystems. The widespread decorative use of E. densa in aquariums, coupled with the potential for subsequent disposal malpractice, has resulted in its introduction into a range of vulnerable ecosystems across the globe. This work presents a dynamic model of a population of E. densa based on its accidental introduction into an ecosystem in southeastern Spain. The model allows the simulation of colonisation process and management and disposal strategies. The model considers the influence of environmental variables such as temperature, light and water turbidity on the growth of the species. Among the management strategies tested, the optimal appears to be those of a preventive nature before the plant spreads, given that the costs of removal will be very high at that stage, and with high ecological impacts.