Oceanographic basis of the global surface distribution of Prochlorococcus ecotypes. by Bouman, H, Ulloa, O, Scanlan, D, Zwirglmaier, K, Li, W, Platt, T, Stuart, V, Barlow, R, Leth, O, Clementson, L, Lutz, V, Fukasawa, M, Watanabe, S, Sathyendranath, S