Mass balance modelling and wetland restoration

As wetland ecosystems become degraded due to human actions, restoration efforts are becoming more pronounced. Developing a successful restoration plan, however, depends on a solid base of knowledge of the system. Mass balance models can provide valuable information about ecosystems with respect to input sources and the relative importance of each load. This study examined phosphorus and suspended solids loadings to Cootes Paradise marsh Hamilton Harbour, Lake Ontario, Canada, through the use of mass balance models. When compared to field data, the models predicted average concentrations well, however large variations occurred on a monthly basis. Relative loadings results suggested that 57% of phosphorus and 68% of suspended solids contributions to Cootes Paradise came from resuspension of the sediments. These inputs were followed in importance by rural runoff and combined sewer overflows for phosphorus and by rural runoff and the creeks for suspended solids. Data, though, are lacking in many areas related to these sources. Improved information is therefore necessary to confirm the contributions from the sediments, runoff and combined sewer overflows before restoration strategies are finalized.