Response of Typha to phosphorus, hydrology, and land use in Lake Ontario coastal wetlands and a companion greenhouse study

Loss of Great Lakes wetlands due to changes in land use, hydrology, nutrient inputs, and invasive species led the need for studies involving physical factors that influence growth cattails (Typha). Thus, 18 Lake Ontario coastal wetlands, we sampled vegetation along stratified random transects collected water samples total phosphorus (TP) analyses. We used GIS determine watershed area, percent use as croplands, length lotic surface waters entering wetlands. A greenhouse experiment with a full factorial block design was investigate effects variable hydroperiod concentrations on T. × glauca biomass changes. Correlation analyses wetland data revealed TP field related croplands but not length; mean Typha TP. In experiment, above- below-ground increased significantly simple main concentrations. Multiple pairwise interaction comparisons between hydrology treatments showed concentration were present only at longer hydroperiods. Lack correlation likely overwhelming effect water-level regulation Ontario. The study demonstrated increasing positively influenced cattail controlled setting. Although growth, hydrologic regime had greatest increased. More natural management inputs may help limit spread Typha.