Effect of arsenic stress on the growth of Typha angustifolia L. in plateau wetlands and its arsenic tolerance

In order to investigate the growth response of typical wetland Typha angustifolia L. to arsenic (As) stress and its tolerance, plant growth and physiological property responding to As stress, As accumulation characteristics as well as As tolerance efficiency were examined in Typha angustifolia L. grown under different As stress levels (0, 50, 100, 150,200, 600 mg·kg⁻¹). The results showed that: ① Plant height, root length, shoot and root dry weight, and lateral shoot number were increased by low-level As while decreased by high-level As. Chlorophyll, MDA and GSH contents showed a similar response and all reached the highest level under 100–150 mg·kg⁻¹ As. Besides, the roots were less sensitive than the shoots, showing greater As resistance. ② The As concentration and distribution in Typha were varied by different As stresses, the As accumulation capacity ranked as follow: shoots > roots and dead leaves > new leaves, indicating that As is predominantly concentrating in the underground part of Typha. ③ The membership function and principal component analysis under various As concentrations showed that Typha is highly resistant to As. The result indicated that Typha may be helpful in the remediation of As-contaminated river lakeside wetlands, providing theoretical basis and technical support for phytoremediation of As-polluted rivers or lakes.