ident-ified northern pike, carp, and yellow perch and possibly smallmouth bass as 

 wetland dependent spawners. Degradation and elimination of wetlands have been 

 associated with collapse of the commercial fisheries of northern pike, muskellunge, 

 lake sturgeon and whitefish in the Great Lakes. -o Tilton, et al. '^ have used capital cost 

 and annual expenses of purchasing wetlands and constructing wetlands to develop 

 estimates that an acre of purchased wetlands had a 1978 worth of $10,644 and 

 constructed wetlands a $22,276 value for northern pike production. 



The SCS wetland evaluation system in Massachusetts represents the sole attempt 

 to develop a comparative rating system for freshwater wetlands as fish habitat." It 

 places relative numerical rankings for fish habitat on wetlands that abut open water. 

 It is based simply on the size of the permanent water body, wetland size and numbers 

 of sport fish species present. But given knowledge available on freshwater fish 

 ecology, it would seem that more sophisticated approaches are feasible and could be 

 important aids in administration of wetland regulations. 



Productivity 



Primary productivity is used as a measure of the effectiveness of a wetland in 

 converting solar energy to a form of energy that may be used to power biological 

 processes w hich sustain life in general and give rise to many of the valuable functions 

 of wetlands. Tidal saline marshes have long been recognized as among the most 

 productive landscape units in the world. Much of the regulation of coastal wetlands 

 has focused on the protection of those marsh communities that most effectively 

 produce organic matter to fuel the biological processes of adjacent waters. Research 

 during the 1970s suggests that freshwater tidal wetlands may be equally productive. ^i 



The Virginia regulatory system'- developed in the last decade, rates coastal plant 

 communities according to their productivity and their location in the tidal flushing 

 pattern. These ratings are used as guides for wetland regulation. Laws in other states 

 often specify certain productive plant communities for prime protection. Measures 

 of productivity may provide a general means to identify highly valuable wetlands,"* 

 but research is lacking on the productivity of many types of freshwater wetlands and 

 on wetlands of the Pacific coast. Few productivity studies have included adequate 

 knowledge of hydrology to document the movement of organic matter produced in 

 the wetland and little is known about below-ground production. This role of 

 wetlands is important to water quality and the production of valuable marine food 

 resources, but those who administer wetlands have only the crudest means to take 

 these values into account when considering permit applications. 



Groundwater Supply 



A widely held assumption is that freshwater wetlands generally recharge 

 groundwater aquifers. Under some conditions, the groundwater system may receive 

 some recharge from wetlands. However, wetland soils are typically less permeable 

 than soils associated with groundwater-recharge areas, so recharge from wetlands 

 will be less than from other areas. Most wetlands occur where water is discharging to 

 the surface from the groundwater system (Figure 5).- In some cases, wetlands in the 

 glaciated northeast are indicators of surficial geology that may contain high yield 

 aquifers-"" for water supply wells that are more economical than surface water 

 supplies."* Where this indicator role prevails, water on the wetland surface is usually 

 not closely related to the water tapped by the wells. 



Research in the past decade-^ has shown that wetlands are indicators of potentially 

 high yield groundwater aquifers in Massachusetts, but further work is needed in 

 other portions of the glaciated landscape, especially where organic soils are 

 extensive. The relationship between wetlands and groundwater in the unglaciated 

 landscape is still a matter for speculation and further research. 



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