Abstract:
Water fluctuations and wave-disturbances are typical habitat characteristics of plateau lakeside wetlands, and the effects on arsenic (As) uptake by macrophyte is still unclear. To explore the effects of water fluctuations and wave-disturbances on the accumulation and transport of As in macrophyte
Typha angustifolia, a series of indoor experiments were conducted. Three different overlying water depths and three different degrees of wave-disturbance were designed to simulate the natural environmental condition of lakeside wetland. The changes in biomass allocation, As content, transport factor, bioconcentration factor and phosphorus/arsenic the between molar ratio (P/As) of different parts of
T. angustifolia under different treatments were measured. The results showed that: (1) With the increase of water depth, the biomass allocation of
T. angustifolia gradually shifted to the above-ground part; under different disturbances treatments, the order of biomass allocated to above-ground part was as follows : low disturbance <no disturbance<high disturbance. (2) The As content in the above-ground part was the highest under the treatment of without-water level (6.23 mg/kg)and high degree disturbance (16.96 mg/kg), while the As content in the underground part was the highest (336.29 mg/kg) under the treatment of high-water level; the degree of disturbance had no significant effect on As content in underground part. (3) The As accumulation and transport in
T. angustifolia were significantly different under different water levels and disturbance degree; the bioconcentration factor (BCF) of As under high-water level treatment was the highest (1.84) , while the transport factor (TF) was the highest (0.05) under high disturbance treatment; in addition, As extraction amount of
T. angustifolia was the largest under high-water level and undisturbed treatment, which were 40.69 mg/plant and 40.39 mg/plant respectively. The results can provide a theoretical basis for regulating environmental factors in the efficient use of
T. angustifolia to carry out ecological remediation of As-contaminated sediment.