In this study, four Theaceae tree species were processed by setting up two hydrogen fluoride concentration gradient (including controls), the actual quantum yield (Y (II)) of PSII, the relative electron transport rate (ETR), non-regulatory energy dissipation quantum yield (Y(NO)), regulatory energy dissipation quantum yield (Y(NPQ)), non-photochemical quenching coefficient (NPQ) and the relative electrical conductivity and other physiological characteristic value were measured, and fuzzy membership function method was applied for comprehensive evaluation and stress resistance sequencing of these four species, which could help to explore the impact of HFstress on physiological indicators of Theacea tree seedlings, and effectively screen out tress species with high resistance to hydrogen fluoride; besides, it could provide the basis for selection of planting trees with the purpose of environmental protection, and also provide a reference for HF stress mechanisms study. This study showed that, under the circumstance of 500 ppm hydrogen fluoride stress, chlorophyll fluorescence indicator of Theaceae tree species presented a downward trend on the whole, which concretely embodied in varying degrees of decline of Y (II) of PSII, ETR, Y (NO), Y (NPQ), NPQ. And the cell membranes of trees species were damaged and the membrane permeability increased. Except for Schima superba, the relative conductivity value of other species showed an upward trend. The capacity of these four species in anti-hydrogen fluoride contamination was Tutcheria championi first, Camellia oleifera second, Schima superba third, Gordonia axillaries is the last.

In this study, we investigated and researched the growth situation of 18 kinds of tree species in the stand improvement plot of environmental protection forests along the hill which is behind the ceramics factory of Gaoming District, Foshan City, Guangdong Province, and we implemented growth situation comparison and cluster analysis of ground diameter, tree height, crown width and clear bole height about these18 kinds of tree species. The result showed that: Michelia macclurei and Schima superba grew the best and had the largest volume of comprehensive growth, and 12 tree species-Ficus altissimo, Syzygium rehderianum, Heteropanax fragrans, Nerium indicum, Acronychia pedunculata, Mytilaria laosensis, Tutcheria championi, Ilex rotunda, Alstonia scholaris, Helicia cochinchinensis, Cinnamomum bodinieri and Carallia brachiata grew well and had a relatively large volume of comprehensive growth with an initial fast-growing result, which could be applied in environmental protection forest.