Readings on phytoplankton and zooplankton

The readings assigned for this topic, available in pdf files under "Course Documents," provide basic information on the life habits and major varieties of floating plants and animals in the Bay system. The two readings from the Environmental Atlas of the Potomac Estuary are most useful for their general description of the different groups of phytoplankton and zooplankton and the role of these groups within the estuarine ecosystem. The information on spatial patterns in the Potomac and seasonal patterns of dominance for different groups is not important for our purposes here - the information is now more than 20 years old and we are not going to focus on the detailed maps of the Potomac estuary anyway. The chapter by Sellner provides more information on the spatial and temporal patterns of phytoplankton abundance in the Bay; we will supplement this with some additional information in class, but we will try very hard to focus mostly on the main trends. The ecological dynamics of phytoplankton populations can get very complicated and difficult to interpret, and we simply don't have the time to get very far into that discussion. The chapter by Day and others provides additional information on the ecology of estuarine zooplankton, but is not focused on Chesapeake Bay. This too will be supplemented by some additional material in class.

The readings from the Web provide a lot of pictures, basic information on phytoplankton and zooplankton biology, and some online articles about their role in the Bay. Look at some of the pages that will tell you about major phytoplankton groups. The two most important, for us, will be diatoms [Bacillariophyta] and dinoflagellates [Pyrrophyta], but you should know at least a little bit about green algae [Chlorophyta] and blue-green algae [Cyanobacteria], and also about zooplankton like copepods, ciliates, and jellyfish. Jellyfish, including the ubiquitous sea nettles, are sometimes referred to as gelatinous zooplankton, and their role in the food web may be quite important. There are some good online articles about them.

One set of items from the web listings that is worth singling out: monitoring data on phytoplankton, zooplankton, and primary production. The page on Remote Sensing of Phytoplankton Blooms can provide digital images of chlorophyll concentrations in the Bay for any of a series of dates. The DNR monitoring station data on phytoplankton will show the annual pattern of abundance for a series of stations in the Bay, broken down by major phytoplankton group. When you look at both of these databases and compare what you see in any given year with what the literature says about a "typical" annual cycle, you may find that there are some discrepancies. In particular, is it really true that the phytoplankton are dominated by a major spring bloom, with a minimum in summer followed by a secondary bloom in the fall? The data seem to show some other things going on and there are significant differences from one year to another. There are also differences in patterns between different monitoring stations.

Additional notes will be handed out in class identifying major spatial and temporal trends in phytoplankton and zooplankton populations from Chesapeake Bay.

1. Library reserve packet:

  2. Pages from the World Wide Web: