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Concentration of 4 heavy metals (Cu, Pb, Zn, Cd) and petroleum hydrocarbon in the surface sediments collected from Chenglingji, Dongting Lake, were quantitatively analyzed. Distribution characteristics and possible sources of the heavy metals and petroleum hydrocarbon were discussed. Methods of single-factor index and geoaccumulation index were adopted to evaluate the potential ecological risks of heavy metal. The results showed that Cd was seriously polluted and in a strong ecological risk level; Cu, Pb and Zn pollution was mild in Chenglingji Port, Dongting Lake. Petroleum hydrocarbon content of nearshore sediment was low exclude of area near Chenglingji Port, which significantly exceeded the standard value. And the content of petroleum hydrocarbon decreased with the distance far away from the harbor.

Galaxolide (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-γ-2- benzopyran, HHCB) is recognized as a novel contaminant in water and has potential adverse impacts on aquatic organisms. The toxic effect of HHCB on Phanerochaete chrysosporium was investigated by exposure of the fungus in nitrogen-limited culture medium to various concentrations of HHCB. DNA damage of P. chrysosporium by HHCB was detected. Comparing with that in the control, the percent polymorphism under different concentrations of HHCB increased, from 21.4% to 42.9%. In addition, the result of UPGMA (un-weighted pair group method of arithmetic means) dendrogram showed that the Simple Matching Coefficient (SM) was decreased with an increase in the concentrations of HHCB. Thus, as an environmental pollutant, HHCB has the toxic effect on P. chrysosporium at molecular level.

The effect of boat-generated waves on mangrove forests could be reflected by width change of tidal inlets by using satellite image in this study. Our results showed that the distributions of mangrove zone on the side of tidal inlets were degenerated by boat-generated waves from 2009 to 2011 in Dongzhai Harbor Mangrove Natural Reserve. The main reason of this change was strong erosion of tidal flat caused by the waves generated by high speed and frequencies boats for tourists. To protect the mangrove forests of the tidal inlets, the drive speed and pass frequencies of the boats in waterway should be restricted and decreased.

To investigate the effect of elevated CO2 and O3 on the accumulation of flavonoids in Ginkgo Biloba leaves, four-year-old trees were exposed in open-top chambers with ambient and twice ambient CO2 and O3 concentrations singly and in combination in 2006. The results show that elevated CO2 reduce the concentrations of keampferol aglycon (-10%), isorhamnetin aglycon (-15%). Elevated O3 reduce the concentrations of the isorhamnetin aglycon (-7%), but increase the concentration of quercetin aglycon (+6%). Under elevated CO2 and O3 in combination, O3-derived effects on flavonoids concentrations are changed by elevated CO2, which are similar to that under the elevated CO2 alone. In conclusion, the concentrations of flavonoids are influenced by the changes in leaf dry mass induced by elevated CO2 and elevated O3. Furthermore, some flavonoids may not respond as antioxidant under ozone stress in ginkgo leaves.