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The fundamental role of hydrology in determining HGM classification and function leads to the assumption that any test of regionalization might do well to begin with a comparison of hydrologic variation within regional subclasses across a geographical or landscape continuum. This paper deals with only the basic hydrologic comparisons between New York, Pennsylvania, and Virginia for similarly classified wetlands in all three regions. Water levels for headwater floodplain wetlands varied substantially between the New York region and the Pennsylvania and Virginia regions; the latter regions were very similar. The same pattern was evident for slope wetlands across the three regions, but there was no significant difference in water levels for riparian depressions. Based upon the hydrologic data alone, it seems that applying the classification outside of central Pennsylvania had mixed results; it worked well south to Virginia and less well north to New York. One substantial influence in New York was the presence of beaver (Castor canadensis) that greatly influenced almost every watershed we worked in. Furthermore, climate differences between the three regions may also have a large impact — the New York sites were subject to much more snow than sites further south.

Developing an understanding of wetland hydrology that is free from site-specific constraints is difficult. Many hydrologic studies are focused upon a single site and the development of water-budget components. Our previous research (Cole et al. 1997) examined the hydrology of several wetlands based upon monthly sampling during the growing season. Those data did not provide adequate information on moisture regimes and did not tell us enough about year-round hydrodynamics. Our new objective was to expand hydrologic analyses to a larger proportion of our reference wetlands and extend them over a longer period of time. We continued to organize our wetlands and our analyses around hydrogeomorphic (HGM) principles. We found ground-water-dominated wetlands (riparian depressions and slopes) to be the wettest sites. Surface-water systems (headwater and mainstem floodplain wetlands) were drier. We found little difference between slopes and the floodplain wetlands in the amount of time water was within the root zone. Riparian depressions were wetter longer, as the average duration of water within the root zone was almost a year for riparian depressions and much less for all other wetland types. Disturbance seemed to play a large role in hydrologic behavior, even more than did HGM classification. We believe that knowledge of HGM subelass might serve as a useful surrogate for actual knowledge of site-specific hydrology. The level of uncertainty increases with surface-water systems, but we have shown a large degree of predictability by HGM subelass. Our data likely have applicability within the entire Ridge and Valley province of the Appalachian Mountains in the United States, although our conclusions have not been tested over that wide latitudinal range.

Currently, no method exists to core large volumes of inland freshwater wetland soils that maintains stratigraphic integrity, minimizes unnecessary disturbance, and cores up to a depth of 50 cm. Our objective was to create a large-volume soil coring device that could be applied with consistency to a variety of wetland substrates. The result is a hand-operated soil corer that resembles the aluminum irrigation pipe corer that DeLaune et al. (1978) used to core soft marshy substrates. Instead of aluminum pipe, we used regular steel stovepipe and a variety of tools for insertion. After the sample is extracted from the sediment, the handle can be quickly removed for ease of transportation and storage of a core. The stovepipe can be cut open to expose the soil sample so that it can easily be sectioned for incremental analysis. The corer was used to take 130 samples in 18 different sites, spanning many different wetland substrate types. Our method has many applications, including radiochronologic dating, seed bank analysis, bulk density measurement, and soil contaminants analysis.