Study On C, N, S And Heavy Metal Pb, Cd, As Accumulation In Urban Forest Community In Pearl River Delta

The environmental benefits were studied through contrastively monitoring biomass dynamic, C, N, S and Pb, Cd, As concentration and reserves in organs in urban forest community, which followed principle in ecosystem ecology, pollution ecology, botanic ecology and environmental biology.(1) There were large aerial arbor biomass in Longjing, Shunde experimental community and Changjiang, Zhongshan contrast community. The total biomass of arbor was 40.44 t·hm^-2 and the ratio of trunk to branch, leaf was 13: 8: 4 in the contrast community. The total biomass of arbor in experimental community was 1.1 times of the contrast community and the ratio of trunk to branch, leaf was 12: 5: 3. Meanwhile, the regression equations were built between biomass(W) of different organs and the D2H in two communities.(2) The results showed that there were many differences about six elements concentration in different organs in two communities. The average C concentrations in leaf, branch and trunk in experimental community were lower than in contrast community. The N concentrations in leaf, branch in experimental communities were higher than in contrast community, but lower in trunk. Concentration of heavy metal Pb in leaf and branch in experimental community was higher than in contrast community, but it was the same in trunk. Concentrations of S and heavy mental Cd, As in organs were higher in experimental community than in contrast community.(3) The results of elements distribution in organs were different. Compared with contrast community, distributions of elements in three organs varied markedly except Pb in experimental community. In contrast community, N, S concentrations in leaf were higher than in branch and trunk evidently, and so did heavy mental element Pb concentration in experimental community. Meanwhile, variations between experimental and contrast communities about the correlation of six elements were evidence.(4) The correlations between concentration of N, S and Pb, Cd in organs and in soil were studied, and so did about N, S concentration between organs and the...