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' <br /> ' T 7 ' h ml h <br /> Wooded swamps ( ype ) are frequently masc aractenzed as botto and azdwoods (Type 1 L), <br /> � however there are significant differences in the hydrological regnnes between the two. The <br /> nature of these differences is discussed in a subsequent section. <br /> R Cowardin Water Regime Modifiers <br /> The purpose of water regime modifiers is to provide a better description of the variations in <br /> hydrology that occur in wetlands on a seasonal and annual basis. These descriptions are general <br /> � in nature because wetland hydrology is e�rdinar�y dynamic. Hydrology is the most variable <br /> component of wetlands and can vary substantiauy within a single basin weekly, monthly, <br /> seasonally, annually and over decades. Extraordinar�y wet or dry periods, whether short or <br /> ' prolonged, do ha.ve dramatic effects on the presence or a�ence of water in any given wetland. <br /> Whether a wetland has naturally occurring hydrology or whether it is partially or completely <br /> drained affects its behavior as a com�onent of the landscape, its appearance, the vegetation that <br /> , inhabits it, and the e�ectiveness of the functions that it perforn�s. Wetlands may also have <br /> artificially induced hydrology due to stormwater inputs or interconnections to other wetlands via <br /> ditch or tile � systerr�s. Careful consideration of each wetland within the overall context of <br /> � the landscape is necessary to understand which water regirr�e best fits along with the special <br /> modifiers that descnbe alterations to wetlands. <br /> , One special modifier class that is missing is the "stormwater pond" category. This is a commonly <br /> occurring condition in ur�n landscapes and should be added. Stormwater ponds may have been <br /> specifically constructed for that purpose or, in the past, previously existing wetlands were used to <br /> , treat stormwater and now function as stormwater ponds rather than"natural"wetlands. <br /> Descriptions of the modi.fiers are taken from Cowardin et al(1979, pgs 21 —22) and from Santos <br /> � and Gauster(1993,pgs 30—32). <br /> Descriptions within the parentheses are ter�rn used on the NWI key and the longer description is <br /> , the one used by Cowardin et al. (1979). Where a paremhetical term is excluded, the two terms <br /> are the sa�. <br /> , ModiBer"A" <br /> Temc�orar�y Flooded(Temuorarv� <br /> Surface water is present for brief periods during the growing season but the water table usually is <br /> � well below the so� surface for �st of the season. Ternporan7y flooded wetlands usually have <br /> plants that are characteristic of both uplands and wetlands. This modifier description is most <br /> ' appropriately assigned to Type 1 and 1L wetlands but clearly does not fit the Type 7 Hardwood <br /> Swamp wetland type. Table 4 (Cowardin et al 1979, pg 28) is inconsistent by including this <br /> regnne in the Type 7 category. <br /> IModiBer"B" <br /> Satarated <br /> � Soil saturation occurs to the surface for extended periods during the growing season but surface <br /> water is seldom present or evident. Many sedge and rush wetlands fit into this category. This <br /> xnodifier also aptly fits the water regfrne that occurs in the hardwood swamps that are present in <br /> , parts of Minnesota in hardwood swamps such as black ash swam}�s and in coniferous swamps <br /> Svoboda Ecological Resources 2180 Abingdon Way <br /> Project No.2007-056-03 Orono,Minnesota <br /> � <br />