microbially available N, reflected in elevated LEU activity, which has been shown to

possibly repress PHE activity.

 Overall enzyme activities within ENP-TS were not drastically lower than the

other enriched sites; in fact, the majority of activities were higher. One contributing

factor to this elevated activity may be due to the UV photolysis of inhibitory polyphenols

and other dissolved C compounds (Wetzel et al., 1995; Boavida and Wetzel, 1998;

Wetzel, 2000). It has been reported that 90% of the solar radiation is absorbed at a depth

of 2.5 cm in the northern Everglades while in the surface water of the southern

Everglades the depth was approximately 10 cm (Qualls and Richardson, 2003). Greater

UV penetration at the ENP-TS enriched site may serve to alleviate the inhibition by

polyphenols, resulting in more efficient community energetic.

 At the ENP-TS reference site, apparent P limitation on C mineralization is

increased to the highest level of any site while TP, TN, TOC, lignin, and cellulose are all

the lowest. It should be noted that phosphatase activities reflect the summation of algal

and bacterial expressed enzymes (Jansson et al., 1988). The production of phosphatase is

most probably the primary motive force, based on the resource allocation strategy,

leading to the decreased production of the C and N acquiring enzymes at this site.

However, BGL activity may also be tied to the resident periphyton community.

Photosynthetically produced extracellular organic carbon (EOC) from the periphyton

community may supply greater amounts of labile carbon that is sufficiently degraded for

direct microbial uptake (Espeland et al., 2001). This may result in the markedly

decreased production of BGL observed at these sites if the majority of DOC released is of

sufficiently low molecular mass. When this readily utilizable carbon is available, there