Macroinvertebrate Responses to a Gradient of Long-Term Nutrient Additions, Altered Hydroperiod, and Fire
The Everglades has been the sentinel ecosystem for illustrating the deleterious effects of agricultural land practices, fire suppression, and hydrological alterations on freshwater wetlands. Numerous studies have illustrated that Everglades biota are adapted for survival under highly oligotrophic conditions (e.g., Browder 1982; Steward and Ornes 1975a,b; Swift and Nicholas 1987; Richardson et al. 1999) and are strongly P limited (reviewed by Noe et al. 2002). Moreover, the natural Everglades ecosystem has evolved under dynamic hydrological conditions, with strong annual wet–dry cycles that are critically coupled with large, periodic fires (e.g., Davis 1994). Thus, it is not surprising that anthropogenic modifications to the natural nutrient, hydrological, and fire regimes of the Everglades during the past few decades have had remarkable effects on biota across all levels of ecological organization (Davis and Ogden 1994).
Although a variety of other human influences have been indicated as stressors to the Everglades, P-enriched runoff from the Everglades Agricultural Area (EAA) has been targeted as the chief offender (SFWMD 1992; Davis and Ogden 1994). The extensive canal and levee system that has compartmentalized the remnant Everglades has served as a conduit for P from the EAA and Lake Okeechobee, and water-control structures have been point sources of P to diked portions of the fen (SFWMD 1992, 2003, 2004, 2005, 2006).
KeywordsImpact Zone Macroinvertebrate Assemblage Taxonomic Resolution Invertebrate Assemblage Species Accumulation Curve
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