FIGURE 3 in Recent changes in abundance and cell size of pelagic diatoms in the North American Great Lakes

FIGURE 3: Change in cell size (µm) for diatoms from sample locations throughout the Great Lakes. Line lengths represent the difference in size between the average for pre-2000 years (1996, 1998, 1999) and post-2000 years (2007, 2008). Sizes for the two periods were based on an average of all measured cells at each location. Seasonal data are presented for all, centric and pennate diatoms. Black, down-pointing lines indicate declines in average cell size at each sample location. Gray, up-pointing lines similarly indicate cell size increases over the sampling period.