Appendix A. Methods on the calibration of YSI-based chlorophyll a readings.
| We obtained and filtered water samples to calibrate the YSI-based chlorophyll a fluorescence readings. We used Whatman GF/F 25-mm diameter filters with nominal porosity of 0.7 μm. We later extracted these filters in the lab and used a Turner Designs Fluorometer to make absolute chlorophyll a readings. From these readings, we developed a linear regression model to convert the YSI chlorophyll a readings into accurate chlorophyll a (μg/L) values. We collected water samples at 12 spatially and temporally distributed sites in 2004 and 7 sites in 2005, with 3 replicate filters extracted from each sample. |