7-3 Lake zonation based on biological function. 



Example given is a moderately deep oligomesotrophic 



Maine lake 7-14 



7-4 Factors and interactions that determine lake 



characteristics (modified from Rawson 1939 by Cole 1975) . . 7-15 



7-5 Idealized energy flow diagram for the pelagic 



portion of a large, deep lake 7-27 



7-6 Energy flow diagram for a particular lake. Generalized 

 relationships of the average energy flow in the pelagic 

 zone of Dalnee Lake, Kamchatka, USSR, during the month 

 of July. Data expressed in calories per square meter 

 per 30 days (from Wetzel 1975; Sorokin and 

 Paveljeva 1972) 7-28 



7-7 Generalized pelagial plankton food web for a Maine lake 



(based on Davis et al. 1978a; and Wetzel 1975) 7-30 



7-8 Generalized food web for the littoral zone of a lake, 

 based on Cummins (1973), Pennak (1953), Wetzel (1975), 

 and R.B. Davis ( unpublished ) . Only certain species 

 of those taxonomic groups listed would be present 7-31 



8-1 Hierarchical classification of the plaustrine 



system in coastal Maine (Cowardin et al . 1977) 8-5 



8-2 Distribution of palustrine wetland classes along a 



continuum from the upland environment to deep water 8-6 



8-3 Two patterns of palustrine succession in coastal Maine 

 (adapted from Wetzel 1975 and Dansereau 

 and Segadas-Vianna 1952) 8-11 



8-4 Five peat bog types recognized by Cameron (1975) 



as existing in coastal Maine 8-14 



8-5 Development of palustrine wetlands on glacial 



terrain (adapted from Heeley and Motts 1976) 8-17 



8-6 Cycling of carbon in a plaustrine wetland (Moore 



and Bellamy 1974) 8-18 



8-7 Model of phosphorus and nitrogen flow 



in the palustrine system 8-20 



8-8 Food web of the forested, scrub/shrub, emergent 



and open water palustrine wetlands 8-28 



8-9 Model of energy flow in the palustrine system 8-29 



xxvi 



