Producers 



Plant species characteristic of palustrine classes in coastal Maine are listed 

 by vegetation type (table 8-5). Palustrine classes are illustrated in figure 

 8-2. It should be noted that emergent perennials growing from substrate 

 usually covered with shallow water are typical of marsh wetlands, whereas 

 emergent perennials forming dense mats are characteristic of bogs. 



A complete list of vascular plant species likely to occur in palustrine areas 

 is given in appendix A. The species composition and distribution of algae, 

 mosses, and other nonvascular plants occurring in palustrine areas have not 

 been studied adequately, nor have the bacterial producers. 



Among the plants characteristic of bogs in coastal Maine are some species of 

 special interest. Sphagnum moss species grow well when nutrient supply is low 

 because they have an ability to accumulate ions necessary for growth from the 

 water. Some plant species supplement their mineral intake by trapping and 

 digesting insects. Carnivorous plants in the Maine coastal zone include the 

 pitcher plant ( Sarracenia purpurea ) , sundew (Drosera spp.), and bladderwort 

 ( Utricularia spp.). 



Plants supply the food energy necessary for the existence of other palustrine 

 organisms (see "Food Webs" below). Vegetation types (which are grouped into 

 classes comprising the palustrine system) differ greatly in their annual pro- 

 duction of organic matter. No data are available on the productivity of 

 palustrine wetlands in coastal Maine. That information at present must be in- 

 ferred from data on similar vegetation types in other areas. The primary pro- 

 ductivity reported for bogs (scrub/shrub, moss/lichen, and certain emergent 

 wetlands) varies greatly (table 8-6). The expected range of productivity for 

 bog systems in coastal Maine is 300 to 1900 g/m^/year dry weight (Moore and 

 Bellamy 1974). A major factor responsible for the low productivities of bogs 

 is the incorporation of available chemicals into peat making them unavailable 

 for plant productivity (see "Energy Flow" below) . Emergent wetlands that have 

 developed as marshes are probably the most productive palustrine vegetation 

 type occurring in the characterization area. Forested wetlands are highly 

 variable in productivity, depending on species composition, but in general can 

 be expected to be lower in productivity than terrestrial forests. Trees of 

 forested wetlands do not grow as well as trees of the same species in terres- 

 trial environments. Curtis (1944 and 1946) found this true of northern white 

 cedar in Maine. Ahlgren and Hansen (1957) found that conifers in northern 

 Minnesota were less flood tolerant than deciduous trees. The productivity of 

 phytoplankton and submersed macrophytes contribute to the productivity of 

 palustrine open waters. Productivities ranging from 200 to 1600 g/m2/year may 

 be expected for the palustrine open water class. As a whole, palustrine 

 wetlands compare favorably with the productivity of temperate forests. 



Plants have important functions in addition to food production. They are of- 

 ten used by animals to build nests and dens. Forested wetlands provide nest- 

 ing sites for many species of hole-nesting birds (e.g., wood ducks, hooded 

 mergansers, woodpeckers). 



8-21 



10-80 



