Table 5. Mean August tissue nutrient concentrations 

 of plant species in Maryland Coastal Plain wetlands. 

 Atlantic white cedar site (n = 48) compared to means 

 ( ± 1 standard error) of species at five non-cedar sites 

 (n = 175). Data from Whigham and Richardson 

 (1988) and Whigham, pers. comm. 



chemistry (Figure 23). The active cation exchange 

 and adsorption capacity of peat (e.g., Gorham 1987), 

 macromolecular aggregates, and Sphagnum mos- 

 ses (e.g. , Clymo 1 963) appear to combine with selec- 

 tive ionic uptake by Chamaecyparis itself to control 

 the water's nutrient content. 



Measurement of all physical components of 

 cedar wetlands will be useful in clarifying the func- 

 tions that control life in an unusual environment. So 

 little data have been accumulated that virtually every 

 observation would be of both theoretical interest and 

 of utility in management. There are great differences 

 between sites; until more is known, it is inappropriate 

 to extrapolate information from one cedar site to any 

 others. 



The scant research on the chemical com- 

 position of soils and vegetation of Atlantic white 

 cedar wetlands has not yet produced a clear picture 

 of cause and effect. This is probably due to the intrin- 

 sic complexity of relationships which are further ob- 

 scured by the differing hydrogeological, lithological, 

 biotic, and anthropogenic components of the sites 

 examined. 



4.6 INTERACTIONS; RESEARCH NEEDED 



Other factors not yet measured in cedar wet- 

 lands also probably play roles in the soil and water 



Cedar wetland soil chemistry appears to dif- 

 fer greatly from its water chemistry. This may provide 

 a clue to the depauperate chemical contents of cedar 

 waters. The soil's active ion exchange, and adsorp- 

 tion processes that remove cations from the water 

 may be part of the mechanism for the accumulation 

 of minerals in Chamaecyparis soil and leaves. 



34 



