Species traits and decomposability predict water quality changes during litter submergence

Plant litter plays an important rule in affecting the water quality of wetland ecosystems. However, it is unknown whether litter decomposability and species traits might predict water quality changes during litter submergence. Here, we conducted a greenhouse experiment to examine the effects of four submerged plant species, together with two water sources (sampled from tourism and protected areas), and oxygen injection treatments on the changes of eight water quality parameters during litter submergence. Our results showed that litter submergence significantly affected water quality changes, and the observed effects changed through time and differed between two water sources, between oxygen injection and the control treatments, and among different litter species. Moreover, water electric conductivity (EC), total dissolved solids (TDS), water total nitrogen (TN), ammonium and nitrite nitrogen increased with increasing initial litter total carbon (TC), TN and total phosphorus (TP), but water dissolved oxygen (DO) decreased with increasing litter TC, TN and TP. Moreover, water EC, TDS and TN increased with the final mass losses after 10-week submergence. These results indicated that species traits (including decomposability) might be good predictors for the water quality changes during litter submergence, and such a trait-based approach might be a promising tool to link plant species diversity via plant functional traits to water quality or other wetland ecosystem services. (C) 2019 Elsevier B.V. All rights reserved.