ABSTRACT
Three species of aquatic
plants (Scirpus validus, Phragmites australis and Acorus calamus) were used as experimental
materials to study their capacity to purify contaminated water and their effects
on water pH and dissolved oxygen (DO). The water was contaminated with different
concentrations of nitrate (5 mg/L, 15 mg/L and 25 mg/L). The results indicated that
the concentration of nitrate, species of aquatic plant and their interaction significantly
impacted denitrification (P = 0.00). Under
the same concentrations, the three species of aquatic plants provided varying degrees
of purification. Acorus calamus provided
effective purification under all three concentrations of nitrate wastewater, with
removal percentages of 87.73%, 83.80% and 86.72% for nitrate concentrations of 5
mg/L, 15 mg/L and 25 mg/L, respectively. In terms of the purification ability by
unit fresh weight, Acorus calamus exhibited
the worst purification capacity, whereas the capacities of Scirpus validus and Phragmites
australis were higher. The purification capacity of Scirpus validus for the three concentrations was as follows: 0.08 mg/(L·g FW), 0.29 mg/(L·g FW), and 0.51 mg/(L·g FW). The capacity of Phragmites australis was 0.07 mg/(L·g FW), 0.25 mg/(L·g FW), and 0.53 mg/(L·g FW). The capacity of Acorus calamus was 0.04 mg/(L·g FW), 0.12 mg/(L·g FW), and 0.21 mg/(L·g FW). Under increased concentrations of nitrate,
the three species of aquatic plants exhibited various degrees of increased purification
capacity. Under the different concentrations of nitrate, the three species exhibited
the same trends with respect to water pH and DO, increasing first and then falling.
The pH remained at approximately 7.5, and the DO fell to 4.0 mg/L. A comprehensive
analysis reveals that Acorus calamus provides
excellent nitrate purification, although by unit fresh weight, both Scirpus validus and Phragmites australis provide superior purification capacity.
Share and Cite:
Li, K. , Liu, L. , Yang, H. , Zhang, C. , Xie, H. and Li, C. (2016) Phytoremediation Potential of Three Species of Macrophytes for Nitrate in Contaminated Water.
American Journal of Plant Sciences,
7, 1259-1267. doi:
10.4236/ajps.2016.78121.