Allometric determinations in the early development of Schoenoplectus californicus to monitor nutrient uptake in constructed wetlands

Studies of Schoenoplectus californicus focus on the development of aboveground biomass estimations. However, below-ground assessments are important for net primary productivity monitoring in wetlands. This study aims to monitor nutrient assimilation by developing allometric models for above and below-ground biomass estimation of S. californicus in constructed wetlands. The plants we evaluated were grown in vitro, allowing us to control the experimental conditions. The results show that shoot length and apex diameter are significant parameters for building our models. Two non-destructive allometric equations were established to predict above and below-ground biomass and the models were highly significant (R² = 0.79 and 0.49, p < 0.001). During active growth, both the aboveground and below-ground components showed to be essential for removing nutrients from the water. Both non-destructive equations allowed the monitoring of biomass accumulation in constructed wetlands for seven months, demonstrating that this low-cost method can be used to evaluate the performance of wetlands for wastewater.