Chapter 5 (Continued) 



Union River estuary 5-33 



Somes Sound 5-33 



Narraguagus River estuary 5-33 



Machias River estuary 5-33 



Denny s River estuary 5-36 



St. Croix River estuary 5-36 



Passamaquoddy and Cobscook Bays 5-36 



Climate 5-38 



Wind 5-38 



Heat budget and precipitation 5-38 



Fog 5-39 



Atmospheric pressure 5-39 



BIOTA 5-39 



Producers 5-40 



Phytoplankton 5-40 



Macroalgae and rooted vegetation 5-41 



Benthic diatoms 5-41 



Microbial producers 5-41 



Consumers 5-41 



Zooplankton 5-41 



Benthic invertebrates 5-41 



Fish 5-44 



Birds 5-44 



Marine mammals 5-47 



Decomposers 5-47 



FOOD WEBS 5-47 



BIOGEOCHEMICAL CYCLES 5-52 



Plant nutrients 5-52 



Nitrogen 5-54 



The Role of Flushing 5-59 



Fore estuary 5-60 



Presumpscot estuary 5-60 



Kennebec estuary 5-62 



Sheepscot estuary 5-63 



Damariscotta estuary 5-63 



Penobscot estuary 5-64 



Pleasant, Narraguagus, and Union estuaries 5-64 



Machias estuary ~. r 5-64 



Cobscook Bay 5-64 



St. Croix estuary 5-64 



Organic Matter Cycle 5-65 



INTERACTIONS AFFECTING 



PRODUCTIVITY AND DISTRIBUTION OF BIOTA 5-67 



Phytoplankton 5-67 



Macroalgae 5-69 



Zooplankton 5-70 



Benthic Invertebrates 5-71 



Decomposers 5-72 



BIOLOGICAL PRODUCTIVITY 5-73 



Primary Productivity 5-73 



Secondary Productivity 5-76 



XV 



10-80 



