Finally, the species of plants nay in- 

 fluence evapotranspiration through their 

 productivity and water-use efficiency. 

 The last category associated with 

 developing soils from marine sediments 

 is the ability of the substrate to sup- 

 ply nutrients. Coarse sands will gen- 

 erally be lower in nutrients than finer 

 textured substrates. Sandy marshes in 

 North Carolina have been shown to re- 

 spond to additions of N and P (see E.D. 

 Seneca - "Techniques for Creating Salt 

 Marshes along the East Coast" in another 

 section of this proceedings). Similarly, 

 marshes in Georgia (Gallagher 1975), 

 Delaware (Sullivan and Daiber 1974), 

 Massachusetts (Valiela and Teal 1974), 

 and Oregon (Gallagher unpublished) have 

 responded to nitrogen applications. 

 Given these soil problems, there 

 are certain plants (occurring in the 

 natural marsh) that have characteristics 

 which may make them useful in facilitat- 

 ing certain desired changes in the sub- 

 strate. These plants are generally not 

 tested experimentally in artifically 

 created marshes; nor has the plasticity 

 of the characteristics to environmental 

 conditions been evaluated. In the ab- 

 sence of such experimentally tested 

 information, consideration of plant 

 characteristics may help the manager to 

 plan his research needs. 



Sporobolus virginicus , Distichlis 

 spicata , and Salicornia virginica are 

 tolerant of a wide range of salinities. 

 Spartina patens is adaptable to growth 

 in the upper marsh and also in drier 

 areas which might be found in the upper 

 levels of dredged material deposits. 

 There are several recommendations 

 for managers who are looking for plants 

 of different rooting depths. The depth 

 of roots may be important for stabiliz- 

 ing soils or for preventing roots from 

 penetrating a soil zone which is inhos- 

 pitable or may contain a contaminant 

 that could be translocated to aerial 

 food webs. The following recommenda- 

 tions are applicable to the southeast 

 and to some extent to the mid-Atlantic 

 States. Sal icornia and Sporobolus are 

 typically shallow rooted. High marsh 

 Spartina alterniflora , Distichlis spi- 

 cata , and Spartina patens grow to inter- 

 mediate depths. Low marsh Spartina 

 alterniflora , Juncus roemerianus , J. 

 gerardi , and Phragmites communis grow 



fairly deep. If the goal is to increase 

 soil leaching, Distichlis spicata , Spar- 

 tina patens , and Sporobolus virginicus 

 are good choices. These same species 

 have high root: shoot ratios that favor 

 quick stabilization. 



If the plant characteristics are 

 not known, an aluminum irrigation pipe 

 corer can be used to sample root systems 

 (Gallagher 1974). This information may 

 help in selection of the proper plant to 

 bring about the desired change in the 

 substrate. 



LITERATURE CITED 



Brady, N.C. 1974. The nature and prop- 

 erty of soils. Macmillan Publish- 

 ing Co., Inc., New York. 639 pp. 



Buol, S.W., F.D. Hale, and R.J. 



Soil genesis and 

 Iowa State Univ. 

 pp. 



Marsh soil of the 



Pages 441-448 j_n 



W. H. Queen, eds. 



halophytes. Academic 



New York. 



soils of the 

 Rookery Bay, 

 Soc. Am. J. 



McCracken. 1973. 

 classification. 

 Press, Ames. 360 



Cotnoir, L. J. 1974. 

 Atlantic coast. 

 R. J. Reimold and 

 Ecology of 

 Press, Inc. 



Coultas, C.L. 1978. The 

 intertidal zone of 

 Florida. Soil Sci. 

 42:111-115. 



Coultas, C. L., and F. G. Calhoun. 

 1976. Properties of some tidal 

 marsh soils of Florida. Soil Sci. 

 Soc. Am. J. 40:72-76. 



Gallagher, J. L. 1974. Sampling macro- 

 organic profiles in salt marsh 

 plant root zones. Soil Sci. Soc. 

 Proc. 38: 154-155. 



Gallagher, J. L. 1975. Effects of am- 

 monium nitrate pulse on the growth 

 and elemental composition of natu- 

 ral stands of Spartina alterniflora 



and 

 62 



Juncus roemerianus. Am. J. Bot. 



644-648. 



Gallagher, J.L. 1977. Zonation of wet- 

 lands and tidelands. Pages 752-758 

 in J. R. Clark, ed. Coastal ecosys- 

 tem management: a technical manual 

 for the conservation of coastal re- 

 sources. John Wiley and Sons, New 

 York. 928 pp. 



Gallagher, J. L., F. G. Plumley, and 

 P.L. Wolf. 1977. Underground bio- 

 mass dynamics and substrate selec- 

 tive properties of Atlantic coastal 

 salt marsh plants. Army Corps 



33 



