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COMPARISON OF SUBSTRATE TYPES
AND TRANSPLANT METHODS IN
CONSTRUCTED SPHAGNUM WETLAND MODELS
Dwight L. Stoltzfus
John W. Munro
Munro Ecological Services, Inc.
990 Old Sumneytown Pike
Harleysville, Pennsylvania 19438
ABSTRACT
Sphagnum wetland models were designed to determine the effectiveness
of hardwood sawdust-wood chip substrate combination in establishing an
organic substrate in newly constructed Sphagnum wetlands.     With an acid
mine drainage affected water source, these emodels were used:       (1) to
determine optimal hydrologic flow rates through the different substrate
combinations, (2) to determine comparative growth rates of Sphagnum fallax
and S. fimbriatum, and (3) to compare the effectiveness of these model
systems in removing iron and manganese. Optimal levels of hydrologic flow
with minimal surface erosion were found with a sawdust-woodchip substrate
combination. Greater growth of S. fallax illustrates the importance of
species selection in the construction of Sphagnum wetlands. Different
transplant methods resulted in varied rates of increase in cover in
relation to the transplant method. A sawdust substrate was initially more
effective in removing iron and manganese.
INTRODUCTION
Sphagnum-dominated  bogs  and   natural  wetlands   occur  in  areas
characterized by low pH, an organic layer of generally less than one
meter, and a water table     level  at or near the surface.      Naturally
occurring areas in Pennsylvania typically are located in areas with acid,
nutrient=poor soils overlying sandstone bedrock.    Wetlands dominated by
Sphagnum, sedge, and grass species are also typical of areas with water
sources affected by acid mine drainage (AMD) resulting from surface-mining
and deep-mining of coal. These areas are characterized by low pH and high
concentrations of iron, manganese, and sulfates.
The importance of developing methods for restoration and creation of
Sphagnum-dominated wetland areas arises out of the need for constructing
these wetlands to replace or restore similar areas that are damaged or
eliminated. Recent studies of the effectiveness of Sphagnum wetlands in
providing for partial treatment of acid mine drainage (Burris, 1984;
Brooks et al., 1985; Hammer, 1989; Wieder, 1990) also show the importance
of continuing the development, improvement, and testing of construction
methods.
Concepts in the design of this 5-year experiment include the use of
plant species present in similar naturally occurring wetland areas, the
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