Facilitation of phosphorus adsorption onto sediment by aquatic plant debris

• Published in: Journal of hazardous materials 2011-07, Vol.191 (1), p.212-218
• Main Authors: Du, S.T., Shentu, J.L., Luo, B.F., Shamsi, I.H., Lin, X.Y., Zhang, Y.S., Jin, C.W.
• Format: Article
• Language: English
• Subjects: Adsorption; Applied sciences; aquatic plants; Biomass; carbon; Cellulose; Chemical engineering; Continental surface waters; Exact sciences and technology; General treatment and storage processes; Geologic Sediments; Glucose; iron; lakes; microbial biomass; Microorganism; Natural water pollution; Phosphorus; Phosphorus - metabolism; Plant debris; Plants - metabolism; Pollution; rivers; Sediment; sediments; Wastes; Water Microbiology; Water treatment and pollution
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2011.04.067

► Aquatic plant debris effects on P flux in water-sediment systems. ► Aquatic plant debris facilitates decrease of soluble reactive P in overlying water. ► Plant components have effect similar to the aquatic plant debris. ► The effect of aquatic plant debris on P flux requires the microbial activity. Aquatic plant debris in lakes or rivers may affect phosphorus flux in water–sediment systems. In this study, either aquatic plant debris or typical plant components (cellulose or glucose), were added into a system of sediment (50 g) and overlying water (2 L) with different initial SRP (soluble reactive phosphorus) concentrations to investigate the impact. After 18 days of treatment with 4 g of plant debris, the SRP in the overlying water for 0.5 and 2 mg L −1 initial SRP tests at 30 °C decreased by 41 and 53%, respectively, compared to the treatments without plant debris. Cellulose and glucose treatments gave similar results as plant debris treatment. When the water–sediment system was sterilized, the cellulose- or glucose-facilitated decrease in SRP vanished. Additionally, in the non-sterilized system, the glucose treatment significantly increased both the microbial biomass carbon and the microbial biomass phosphorous in the sediment. Although total phosphorous in the sediment increased with glucose treatment, its water soluble and iron associated inorganic fractions, two labile phosphorus fractions, were clearly reduced. Our results suggest that the short-term retention of plant debris in water systems facilitates a decrease in overlying water SRP through microbe-mediated mechanisms of phosphorus adsorption and stabilization in sediment.