Spatio-temporal Variation in Nutrient Profiles and Exchange Fluxes at the Sediment-Water Interface in Yuqiao Reservoir, China

Int J Environ Res Public Health. 2019 Aug 23;16(17):3071. doi: 10.3390/ijerph16173071.

Abstract

Nutrients released from sediments have a significant influence on the water quality in eutrophic lakes and reservoirs. To clarify the internal nutrient load and provide reference for eutrophication control in Yuqiao Reservoir, a drinking water source reservoir in China, pore water profiles and sediment core incubation experiments were conducted. The nutrients in the water (soluble reactive P (SRP), nitrate-N (NO3--N), nitrite-N (NO2--N), and ammonium-N (NH4+-N)) and in the sediments (total N (TN), total P (TP) and total organic carbon (TOC)) were quantified. The results show that NH4+-N was the main component of inorganic N in the pore water. NH4+-N and SRP were higher in the pore water than in the overlying water, and the concentration gradient indicated a diffusion potential from the sediment to the overlying water. The NH4+-N, NO3--N, and SRP fluxes showed significant differences amongst the seasons. The NH4+-N and SRP fluxes were significantly higher in the summer than in other seasons, while NO3--N was higher in the autumn. The sediment generally acted as a source of NH4+-N and SRP and as a sink for NO3--N and NO2--N. The sediments release 1133.15 and 92.46 tons of N and P, respectively, to the overlying water each year.

Keywords: Yuqiao Reservoir; flux; nutrient; pore water; sediment-water interface.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • China
  • Environmental Monitoring* / methods
  • Eutrophication / physiology
  • Geologic Sediments / chemistry*
  • Humans
  • Lakes / chemistry*
  • Nutrients
  • Spatio-Temporal Analysis
  • Water Pollutants, Chemical / analysis*
  • Water Quality / standards

Substances

  • Water Pollutants, Chemical