Impacts of the amount of hybrid cattail (Typha x glauca) litter on abiotic and biotic conditions in prairie pothole wetlands
Hybrid cattail (Typha x glauca) is an invasive emergent macrophyte that spreads quickly and forms monodominant stands in wetlands, and alters their abiotic and biotic conditions. I examined the role that cattail litter has on abiotic and biotic conditions. Specifically, I studied experimentally the effects of the amount of litter in a mesocosm complex and a prairie pothole wetland. At both sites, I established three litter treatments (high, control, and low litter amounts) and examined how the amount of litter effects litter decomposition, cattail shoot number and height, temperature (at the sediment surface, as well as 10cm above and 10cm below), soil redox potential, dissolved oxygen, and percent oxygen saturation. I hypothesized that when litter increased at a site, there would be a corresponding decrease in soil and water temperature, redox potential, dissolved oxygen, and percent oxygen saturation and consequently in the rate of litter decomposition. I also hypothesized that the number of cattail shoots and cattail shoot heights would decrease with increasing litter.
There was no significant difference among the litter treatments in litter decomposition rates at either location. Temperatures varied across treatments, with a greater mean maximum and minimum in the low treatment at all three depths (+10cm, 0cm, -10cm) at the mesocosm complex, but not at Anderson Lake. Redox potential, dissolved oxygen, and percent oxygen saturation in the low treatments at the mesocosm complex were significantly higher than in either the high or control treatments, but again not at Anderson Lake. The number of cattail shoots was significantly higher in the low treatments than in the high and control treatments in the mesocosm complex and between the low and high treatments at Anderson Lake.