increase in water-column Chi a (Carpenter and Lodge 1986). Landers 

 (1982) estimated that approximately 18% of the annual P loading in 

 Lake Monroe, Indiana originated from senescing macrophytes. 

 Carpenter (1981) also concluded that most of the dissolved organic 

 carbon and dissolved total P in Lake Wingra, Wisconsin was released 

 during decomposition of Myriophyllum spicatum in the littoral zone. 

 Filbin and Barko (1985) have concluded that the release of 

 sedimentary nutrients into the water column by macrophytes may 

 be more significant in lakes than in reservoirs because of the 

 riverine nature of reservoirs. 



Macrophytes have several influences on the sedimentation 

 patterns in lakes where they are found. Macrophytes tend to 

 intercept or modify the flow of materials such as sediment from land 

 to the pelagic zone. By reducing water velocity and wave action, 

 macrophytes function as sediment traps in the littoral zone. This 

 effect was shown to be significant in historical changes in 

 sedimentation patterns of Lough Augher, Northern Ireland 

 (Anderson 1990b). When macrophytes die, their biomass increases 

 sedimentary organic matter content and leads to an accretion of 

 littoral sediment that promotes infilling of the lake basin and 

 expansion of emergent vegetation (Carpenter 1981, Carpenter and 

 Lodge 1986). Macrophyte presence in lakes, therefore, accelerates 

 infilling and senescence of lakes. 



Macrophytes provide a complex habitat, and their presence leads 

 to an increase in those species commonly found in littoral areas. 

 When macrophytes are present, epiphytic algae proliferate and an 

 increase is observed in epiphytic grazers such as snails (Carpenter 



