PM2.5 aerosols were collected in forests along north latitude in boreal-temperate, temperate, subtropical and tropical climatic zones in eastern China, i.e., Changbai Mountain Nature Reserve （CB）, Dongping National ...PM2.5 aerosols were collected in forests along north latitude in boreal-temperate, temperate, subtropical and tropical climatic zones in eastern China, i.e., Changbai Mountain Nature Reserve （CB）, Dongping National Forest Park in Chongming Island （CM）, Dinghu Mountain Nature Reserve （DH）, Jianfengling Nature Reserve in Hainan Island （HN）. The mass concentrations of PM2.5, organic carbon （OC）, elemental carbon （EC）, water soluble organic carbon （WSOC） as well as concentrations of ten inorganic ions （F？, Cl？, NO3？, SO42？, C2O42？, NH4＋, Na＋, K＋, Ca2＋, Mg2＋） were determined. Aerosol chemical mass closures were achieved. The 24-hr average concentrations of PM2.5 were 38.8, 89.2, 30.4, 18 μg/m3 at CB, CM, DH and HN, respectively. Organic matter and EC accounted for 21%–33% and 1.3%–2.3% of PM2.5 mass, respectively. The sum of three dominant secondary ions （SO42-, NO3-, NH4＋） accounted for 44%, 50%, 45% and 16% of local PM2.5 mass at CB, CM, DH and HN, respectively. WSOC comprised 35%–65% of OC. The sources of PM2.5 include especially important regional anthropogenic pollutions at Chinese forest areas.展开更多
Carbon of humus acids(HSAC) and dissolved organic carbon(DOC) are the most active forms of soil organic carbon(SOC) and play an important role in global carbon recycling. We investigated the concentrations of HSAC,wat...Carbon of humus acids(HSAC) and dissolved organic carbon(DOC) are the most active forms of soil organic carbon(SOC) and play an important role in global carbon recycling. We investigated the concentrations of HSAC,water-soluble organic carbon(WSOC),hot water-extractable organic carbon(HWOC) and SOC in soils under different vegetation types of four copper mine tailings sites with differing vegetation succession time periods in Tongling,China. The concentrations of HSAC,WSOC,HWOC and SOC increased with vegetation succession. WSOC concentration increased with the accumulation of SOC in the tailings,and a linearly positive correlation existed between the concentrations of HSAC and SOC in the tailings. However,the percentages of HSAC and DOC in the SOC decreased during vegetation succession. The rate of SOC accumulation was higher when the succession time was longer than 20 years,whereas the speeds of soil organic matter(SOM) decomposition and humification were slow,and the concentrations of HSAC and DOC increased slowly in the tailings. The percentage of carbon of humic acid(HAC) in HSAC increased with vegetation succession,and the values of humification index(HI),HAC/carbon of fulvic acid,also increased with the accumulation of HSAC and SOC in soils of the tailings sites. However,the HI value in the each of the tailings was less than 0.50. The humification rate of SOM was lower than the accumulation rate of SOM,and the level of soil fertility was still very low in the tailings even after 40 years of natural restoration.展开更多
基金supported by the National Natrual Science Foundation of China (No. 20677036, 20877051)the Shanghai Leading Academic Disciplines (No. S30109)+1 种基金the Scientific Research Foundation for Returned Overseas Chinese Scholars, State Education Ministrysupported by the Graduate Innovative Fund from Shanghai University
文摘PM2.5 aerosols were collected in forests along north latitude in boreal-temperate, temperate, subtropical and tropical climatic zones in eastern China, i.e., Changbai Mountain Nature Reserve （CB）, Dongping National Forest Park in Chongming Island （CM）, Dinghu Mountain Nature Reserve （DH）, Jianfengling Nature Reserve in Hainan Island （HN）. The mass concentrations of PM2.5, organic carbon （OC）, elemental carbon （EC）, water soluble organic carbon （WSOC） as well as concentrations of ten inorganic ions （F？, Cl？, NO3？, SO42？, C2O42？, NH4＋, Na＋, K＋, Ca2＋, Mg2＋） were determined. Aerosol chemical mass closures were achieved. The 24-hr average concentrations of PM2.5 were 38.8, 89.2, 30.4, 18 μg/m3 at CB, CM, DH and HN, respectively. Organic matter and EC accounted for 21%–33% and 1.3%–2.3% of PM2.5 mass, respectively. The sum of three dominant secondary ions （SO42-, NO3-, NH4＋） accounted for 44%, 50%, 45% and 16% of local PM2.5 mass at CB, CM, DH and HN, respectively. WSOC comprised 35%–65% of OC. The sources of PM2.5 include especially important regional anthropogenic pollutions at Chinese forest areas.
基金Supported by the National High Technology Research and Development Program(863 Program)of China(No.2006AA06Z359)the National Environmental Protection Public Welfare Science and Technology Research Program of China(No.201009041)the Special Foundation for Young Scientists of Anhui Province,China(No.2010SQRL150)
文摘Carbon of humus acids(HSAC) and dissolved organic carbon(DOC) are the most active forms of soil organic carbon(SOC) and play an important role in global carbon recycling. We investigated the concentrations of HSAC,water-soluble organic carbon(WSOC),hot water-extractable organic carbon(HWOC) and SOC in soils under different vegetation types of four copper mine tailings sites with differing vegetation succession time periods in Tongling,China. The concentrations of HSAC,WSOC,HWOC and SOC increased with vegetation succession. WSOC concentration increased with the accumulation of SOC in the tailings,and a linearly positive correlation existed between the concentrations of HSAC and SOC in the tailings. However,the percentages of HSAC and DOC in the SOC decreased during vegetation succession. The rate of SOC accumulation was higher when the succession time was longer than 20 years,whereas the speeds of soil organic matter(SOM) decomposition and humification were slow,and the concentrations of HSAC and DOC increased slowly in the tailings. The percentage of carbon of humic acid(HAC) in HSAC increased with vegetation succession,and the values of humification index(HI),HAC/carbon of fulvic acid,also increased with the accumulation of HSAC and SOC in soils of the tailings sites. However,the HI value in the each of the tailings was less than 0.50. The humification rate of SOM was lower than the accumulation rate of SOM,and the level of soil fertility was still very low in the tailings even after 40 years of natural restoration.
