Abstract: This paper deals with studies on the stomatal resistance of plants in different polluted environment in the Fuzhou region and their use in evaluating the quality of atmospheric environment. The results show that among the seven function areas under investigation, the plants in Mawei, Guantou and Fuzhou have larger stomatal resistance, the average value is 6–7s cm. In Mawei function area, half of the plants have normal stomatal resistance of 2–4s/cm, only in a few industrial-mining and heavy-traffic areas, the stomatal resistance of plants is 6–12s/cm, which is of grade Ⅲ to Ⅱ and exceeds the normal level, indicating that these areas have been lightly polluted. In the other four function areas (Gushan, Tingjiang, Changle, Minhou), the average value of stomatal resistance is 3s/cm, which is of grade Ⅳ or normal. The average value of stomatal resistance in the sixty observation sites is 4.14s/cm, which is a little higher than the normal level. From the stomataJ resistance values we can infer that the stomatal openings of most plants in the Fnzhou region are normal, but the transpiration rate of plants is comparatively low, which is 5.19μgH20 cm-2·s-1 in average. This is due to the moist subtropics climate where the precipitation and vapourization is similar in amount. The stomatal resistance value not only correlates positively with the pollutant contents in leaves, but also conforms to the polluted states of SO2 and TSP. From what we have mentioned above we can conclude that the Fuzhon region is not polluted except for a few industrial-mining, heavy traffic and crowded sightseeing areas which are only lightly polluted. This conclusion is in agreement with that of the local environmental monitoring department, that is, "the present environmental quality of the Fuzhou Economic-Technological Development Region is fine". We believe that it is an ideal means to use stomatal resistance index of plants in evaluating the quality of atmospheric environment.

Key words: Stomatal diffusive resistance of plants, Quality of atmospheric environment, Evaluation, Transpiration rate