newly colonized infant hummocks. The data suggest that sometime between the
construction of wetland hummocks and seven years of age hummocks reach structural
equilibrium. Structural equilibrium refers to both soils having finished settling and
erosion and deposition being relatively equal. Buildup of organic matter may occur
causing the apparent growth in the Iluka hummocks. It should be noted that completely
accurate height measurement was made difficult by low lying tree limbs interfering with
laser level rod positioning. Drastic changes in the results due to the error are unlikely, as
extra time was taken to position the rod carefully for measurement. Comparing the
hummocks in the other two wetlands over the first two sampling periods shows that the
organic hummocks in the Agrifos wetland have more decay than the organic hummocks
in the Cargill wetland. Both have high percent cover of vegetation to bind soils. The big
difference is the composition of the soils. The Agrifos soils, being completely organic in
nature, likely decomposed faster than the sandy muck used in the Cargill wetland. The
overburden hummocks showed similar erosion, although differences were seen between
major and minor transects. Weathering patterns along the transects show differences due
to the direction of the prevailing wind and the direction of rainfall hitting the hummocks.
No comparison with the sand hummocks in the Agrifos wetland can be made as none
were constructed in the other wetlands.

 Soil moisture values reflect not only the soil type, but also the level of surface
 water in the wetland. Values for the hummocks in the Agrifos wetland increase as surface
 water increases as do those in the other two wetlands. Comparing the soil pore water for
 the different hummock types becomes tricky because the surface water level is different
 in each wetland. The only accurate way to determine each soil's ability to hold water
 would be by taking soil cores and running tests in laboratory conditions. The data
 available from this study suggest that in flooded conditions (Figure 5.22, Figure 5.25, and
 Figure A38), values are similar for the overburden hummocks in all three wetlands. The
 values suggest that the composition of the overburden soils give them similar properties.
 The organic hummocks in the Agrifos and Cargill wetlands show slightly different
 averages with the Agrifos hummocks made of yard compost being higher. Based on the
 origin of each soil type, this variation would be expected. Again, no comparison can be
 made with sand tailings as only the Agrifos wetland had sand hummocks. It is interesting
 to note the increase in r2 values for graphs of volumetric water content versus elevation in
 each wetland. The trend suggests that, as hummocks age and equilibrium is reached, the
 soil becomes uniform in its ability to hold pore water.

 Vegetation growth on the hummocks shows that the mature Iluka wetland's
overburden hummocks have the highest diversity (s) and highest Shannon diversity
(Table 5.1). The evenness (J') is among the highest as well indicating even distribution
among species. The age of the hummocks may be the reason more species and higher
diversity were recorded. More stable conditions reached during equilibrium may promote
the growth of more species. Climatic conditions, soil composition, nutrient availability
may all influence the diversity as well. While the Agrifos overburden hummocks have
similar high values for diversity, the Cargill overburden hummocks show much lower
diversities. This may be attributed to the late construction of the Cargill site. Different


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