The influence of viral infection on a plankton ecosystem undergoing nutrient enrichment.

It is increasingly recognised that viruses are a significant active component of oceanic plankton ecosystems. They play an important role in biogeochemical cycles as well as being implicated in observed patterns of species abundance and diversity. The influence of viral infection in plankton ecosystems is not fully understood. Here we use a number of well-founded mathematical models to investigate the interplay of the ecological and epidemiological interactions of plankton and viruses in the sea. Of particular interest is the role of nutrient on the population dynamics. Nutrient forcing has been suggested as a means of absorbing excess anthropogenic atmospheric carbon dioxide by stimulating increased phytoplankton primary productivity. Here we show that enriching nutrient levels in the sea may decrease the amount of infected phytoplankton species thereby additionally enhancing the efficiency of the biological pump, a means by which carbon is transferred from the atmosphere to the deep ocean.