those reported in a previous study (Wright et al., 2001b). LNWR, WCA-2A, and WCA-

3A exhibited a similar range of TN and TOC values. ENP-TS TN concentrations were as

much as 64% lower at the ENR site and 70% lower at the REF site. Correspondingly,

ENP-TS TOC concentrations were as much as 61% and 64% lower at the ENR and REF

sites, respectively. TN was most strongly correlated with TOC and lignin and negatively

correlated with calcium (Table 4-3). TOC was most strongly correlated with TP, TN,

lignin, and negatively correlated with calcium (Table 4-3).

 Calcium concentrations were the highest in ENP-TS, with values as great as 400 to

1800% higher in the enriched and reference sites, respectively. The only significant

change along the gradient occurred in LNWR with a higher concentration at the enriched

site. Increases in Ca have been shown to increase with P loading due to release from

organic matter (Newman et al., 2001). Mg concentrations were between 150% and

338% greater in LNWR and WCA-2A than the other two areas sampled and did not vary

significantly along the gradient.

 Benthic C:P values were significantly higher at the reference sites in all four study

areas. The largest difference in C:P values within an area occurred in ENP-TS with

values of 236 and 1803 at the ENR and REF sites, respectively. Benthic C:N ratios

ranged from 11.5 to 14.4 and were significantly lower at the reference sites (6 of 12

comparisons), with the exception of ENP-TS. The largest range of N:P values were 18.2

to 123.6 in ENP-TS, reflecting the minimum and maximum values among the areas. N:P

values increased significantly with increasing distance from the canal in all areas.