Abstract:

This paper studies on the functional value of urban forest in Guangzhou about its purifying SO₂,hydrofluoric acid and intercepting dust. The result shows that, the anti-sulfur intensity scale of main urban forest is between 7.740 and 0.051 mg·g^-1. Different types of tree purification capacity of sulfur is 365.278～36.836 kg·hm^-2a^-1, and its total value is 1.433×10 ⁴ t5a^-1, which equals to 2.865×10⁴ t SO₂·a^-1 And its potential purification capacity of SO₂ is 5.683×10.4 t·a^-1; urban forest can absorb fluorine 3 07852 t·a^-1, equal to hydro fluoric acid 3 240.45 t·a^-1, among them, Lysidice rhodostegia, Aporosa chinensis and Chinese banyan are good at absorbing fluorine, while Citrus is the worst; the open forest along urban has the biggest capacity of absorbing fluorine（22.551 kg·hm^-2a^-1）, and the economic forest the worst(1.974 kg·hm^-2a^-1); The urban forest in Guangzhou can be classified into 7 types, their average percentage of dust catching capacity is between 23.5% and 53.5% in fine and overcast days, the total average percentage is 39.93%，and the total amount is 6.076×10⁴ t·a^-1; the filtering SO₂and hydrofluoric acid, and catching dust functional value of the urban forest in Guangzhou City is 113 796.54×10⁴ yuan·a^-1.

Key words: urban forest, purification function, economic value, Guangzhou