In Situ Monitoring of a Eutrophicated Pond Revealed Complex Dynamics of Nitrogen and Phosphorus Triggered by Decomposition of Floating-Leaved Macrophytes

To explore the influence of decomposition aquatic macrophytes on water quality in eutrophicated ecosystems and interacting environmental factors that trigger nitrogen (N) phosphorus (P) dynamics, a suburban pond with floating-leaved (Pond A) as well another nearby newly dug without any obvious B) were studied. N P levels together series parameters relating to biomass, sediments monitored during period 84 d covered entire process plants. The results show can be divided into two phases, first phase having faster rate second phase, slower one. With dissolved oxygen (DO), oxidation-reduction potential (ORP), pondus hydrogenii (pH) body increased, whereas permanganate index (CODMn) decreased. Significantly higher total both sediment (TPW TPS) detected Pond A macrophytes; TPW increased quickly biomass but decreased TPS remained relatively stable slowly phase. Total (TNW TNS) was also significantly stable. structural equation model revealed macrophytes, could, directly indirectly, cycles an ecosystem through regulation pH DO. Our study indicate exerted greater than N. Besides direct release from decaying which caused significant increase body, changes DO ORP subsequent redox state whole system indirectly affected deposition dissolution between water. decisive factor endogenous eutrophication ponds containing macrophytes.