Figure 5.

Importance of marine ecoregions based on ballast water propagules, by decay parameter λ. (a) Arrivals and (b) sources. Vertical line indicates the parameter choice from [29]. Includes all ecoregions that at any point on the scale are part of the top 8 or 17 most important ports, respectively. At the level indicated by the vertical line, these ports account for more than 95% of the projected incoming ballast propagules. Note that λ=0 implies no decay, i.e. the ranking is based solely on volume of ballast water discharged.