0.

LU


 83



70

60 -
 Enr WCA-3A
50-

40 nr

30


 Ref WCA-2A
 10


 Ref ENP-TS
 10
 0 02 04 06 08 1 12 14 16 18 2
 Ecell/En


Figure 4-2. Benthic layer bubble plot of Ecell/Ep vs. Ecell/En with Ecell/Eox
 represented by the bubble size. Arrows denote shifts from the enriched
 to the corresponding reference sites.



support this by suggesting that the highest TP impact (0.83) occurs along the ENP-TS


gradient. However, the TP values are lower at both the enriched and reference sites, so

the increases may not be enough to induce resource allocation shifts along the gradient.


In this case it does not appear that the impact index accurately reflects the severity of


impacts in relation to significant changes that may be occurring within the communities.

The greatest shift in P influence on C mineralization therefore appears to occur within


WCA-3A with the smallest shift within ENP-TS.


 Ecell/En values were higher at all the enriched sites, once again to differing


degrees. The largest shift occurred within ENP-TS (Figure 4-2), which also had the


highest Ecell/En impact index. The higher Ecell/En and Ecell/Ep values at all the


enriched sites are concurrent with decreases in nutrient limitations that have been


documented (McCormick et al., 1996), as well as lower P mineralization rates in enriched


areas of the Everglades (Newman et al., 2003; White and Reddy, 2000).