The geology of the Maine coast plays a large role in controlling the size and 

 type of decomposers. Dale (1974) reported that the abundance of bacteria 

 associated with sediments in an intertidal basin at Petpeswick Inlet, Nova 

 Scotia, was correlated highly with grain size and other sedimentary 

 properties. A fine silty or sandy bottom supported a large bacterial 

 population and a rocky or cobble bottom supported a smaller population. 



The upper intertidal pools in the characterization area harbor unique 

 bacterial communities. Certain "salt-tolerant" bacteria were found in tidal 

 pools in nearby St. Andrews, New Brunswick, Canada (Forsyth et al. 1971). 

 They concluded that the increased salt concentrations in these pools, 

 resulting from evaporation, supported these bacteria. 



BIOLOGICAL PRODUCTIVITY 



Primary Productivity 



Primary productivity, the rate of input of photosynthetically fixed organic 

 carbon, is fundamental to the maintenance of marine and estuarine biological 

 systems. While plant communities provide many potentially important 

 requirements of other organisms (e.g., food, nest sites, shelter, and roosting 

 sites), their relative importance to marine or estuarine systems may be 

 measured best by comparing their primary productivity. All references to 

 production here refer to net production, which is that production stored as 

 chemical energy after respiratory demands have been met. 



Although too little data are available to predict accurately marine or 

 estuarine primary productivity in Maine, it is possible to estimate the 

 primary productivity of some of the important plant groups. Such estimates 

 facilitate comparisons between the primary productivity in various plant 

 groups characteristic of specific habitats. These comparisons aid in 

 understanding plants' functional relationships in coastal Maine. Those plant 

 groups that have measurable primary production, based on biomass, carbon 

 content, carbon assimilation, and habitat coverage, are phytoplankton, 

 intertidal macroalgae, and the taxonomically higher plants of emergent 

 wetlands, which are described below. The productivity of other plant groups, 

 such as those algae that inhabit mudflats and salt marshes, are so poorly 

 understood that annual productivity estimates cannot be made. Input of 

 organic matter from land drainage and rivers is yet another source of 

 production not adequately addressed. 



Measurements were made of intertidal macroalgal biomass and the substrata 

 generally suitable for colonization by large seaweeds [e.g., stones greater 

 than approximately 2.5 inches (6.4 cm) in diameter] at 46 randomly selected 

 sites throughout Lincoln County (region 2; Topinka and Tucker, unpublished ) . 

 The wet weight biomass on suitable rocky substrata averaged 18 pounds (8 kg) 

 of macroalgae/m . Over 90% of the biomass was rockweed. Previous studies of 

 this species suggested that approximately 10.3% of its wet weight was carbon. 

 On this basis the quantity of macroalgal carbon per unit area of suitable 

 rocky area was determined to be 823 g C/m^ . This is the standing stock of 

 carbon and will serve as a point of reference in subsequent productivity 

 estimates . 



5-73 



10-80 



