Seasonal Dynamics of Nitrogen and Phosphorus in Wetland Plants: Implications for Efficient Eutrophication Control

Eutrophication challenges aquatic ecosystems, with wetland plants serving as sustainable sources of in situ remediation for nitrogen (N) and phosphorus (P) removal. The limited understanding of seasonal nutrient dynamics hinders sustainable management development. This review classifies wetland plants by growth patterns: spring–summer growth plants (SSPs), spring–summer–autumn growth plants (SSAPs), and all-year-round growth plants (APs). SSPs exhibit peak N/P in spring–summer, SSAPs sustain high levels in autumn, while APs maintain stable contents through cold-tolerant sustainability. Perennials achieve sustainable cycling by seasonally storing N/P in tissues and redistributing them in spring. We propose the following sustainable harvesting protocols: harvest SSPs pre-September, SSAPs by November, and retain APs over winter. Height-controlled harvesting during growth peaks enhances removal while preserving regeneration. Strategic combinations of SSPs, SSAPs, and APs ensure sustainable, efficient nutrient removal across hydrological/climatic conditions, supporting wetland conservation.