Chlorophyll synthesis and enzyme activities in plants are sensitive under adverse condition and can provide precise information on any perturbation occuring in plant [24]. In the present study, chlorophyll contents in leaves of giant reed increased at 1.25 and 2.5 mmol/kg of AA addition, while decreased sharply at 5.0 mmol/kg treatment accompanied with biomass decrease (Table 4). Similarly, chlorophyll content in leaves was increased by 72.2% amended with high level CA in comparison to the control, which was in agreement with the change of biomass, suggesting that CA application did not deteriorate photosynthetic parameters of plant [25]. The activities of SOD and CAT increased resistance to the stress of multi-metals, especially CAT played a role in defying As, Cd, Pb-induced oxidative stress in plant [26].