Based on pot experiments, the effect of acid rain stress on membrane protective system of spinach and the conservation of rare earth elements were studied. The stress of acid rain resulted in decreases of overall levels of superoxide dismutase activity and catalase activity, and on increase of peroxidase activity. After being treated by rare earth elements, the overall level of superoxide dismutase activity and catalase activity were increase and the peak value of activity variation curve moved forward to t...