Responses of coastal sediment phosphorus release to elevated urea loading

Ma S., Dong X., Jeppesen E., Sondergaard M., Cao J., Li Y., ...Daha Fazla

MARINE POLLUTION BULLETIN, cilt.174, 2022 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 174
  • Basım Tarihi: 2022
  • Doi Numarası: 10.1016/j.marpolbul.2021.113203
  • Dergi Adı: MARINE POLLUTION BULLETIN
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, PASCAL, Aerospace Database, Agricultural & Environmental Science Database, Aquatic Science & Fisheries Abstracts (ASFA), Artic & Antarctic Regions, BIOSIS, CAB Abstracts, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, EMBASE, Environment Index, Geobase, MEDLINE, Metadex, Pollution Abstracts, Veterinary Science Database, Civil Engineering Abstracts
  • Anahtar Kelimeler: Coastal eutrophication, Urea pollution and transformation, Phosphorus release, Phosphorus-solubilizing bacteria, Sediment pH, Oxidation of sediment, NITROGEN, CARBON
  • Orta Doğu Teknik Üniversitesi Adresli: Hayır

Özet

Increased urea is one of the common nitrogen forms polluting coastal waters and affecting nutrient dynamics. To investigate the effects of urea on sediment phosphorus (P) release, we carried out a 2-month mesocosm experiment with six targeted loadings of urea (0-0.6 mg N L-1 d(-1)). Results showed that: i) urea was rapidly transformed into ammonium and then nitrate (NO3-). ii) When nitrogen occurred as urea or ammonium, minor P release was observed. iii) After urea were mostly converted to NO3-, P release became clearer. iv) NO3- had a dual effect by promoting P release through decreasing sediment pH and increasing alkaline phosphatase activity or by inhibiting P release through improving sediment oxidation. v) The overall effects of urea on P release depended on the ultimate NO3- concentrations, being prominent when NO3- >= 11 mg N L-1. Our findings are of relevance when determining nitrogen reduction targets needed for combating eutrophication.