百年来海州湾沉积物中黑碳分布特征及环境意义OA北大核心CSTPCD

Black carbon in sediments has reflected changes in local biomass-burning characteristics for over a century.In this work,the progress of biomass burning in Haizhou Bay during the past 100 years was analyzed via independent measurement of sediment black carbon,char,and soot in sediment core samples using the thermal-optical reflectance(TOR)method.Furthermore,correlation analysis,principal component analysis,and the characteristic ratio approach were employed to discover the transformation of the region's energy structure over the past century and examine histori-cal variations and potential sources of black carbon contents.The data demonstrated a remarkable vertical change in the mass fration of sediment black carbon,char,and soot over the past 100 years,revealing range variations of 0.507-1.281,0.395-1.080,and 0.112-0.389 mg·g-1,respectively.The highest concentrations of black carbon(0.873-1.029 mg·g-1)were recorded in the mid-late 1980s,whereas the lowest mass fration(0.675-0.751 mg·g-1)were reported in the 1920s and the middle of the 20th century.The peak black carbon flux in developed areas emerged earlier,reflecting the signifi-cant correlation between black carbon deposition,regional industrialization level,and human activities;for instance,the contents in China's eastern marginal sea area are 10 times higher than those in the Qinghai-Xizang Plateau and Swedish lakes.The results of the source analysis using the char/soot characteristic ratio method revealed that black carbon sources from fossil fuel combustion represented 48.8%of the total,which was 4.2 times more than sources from biomass burning.Moreover,the results of the correlation analysis,principal component analysis,and char/soot ratio indicated the follow-ing.The main source of black carbon was biomass combustion before 1950,and the percentages of coal combustion,industrial sources,and transportation sources increased after 1950.The population of the region and the value of its gross industrial output,energy consumption,and other factors influenced these findings,and human activities predominated.The findings of this study serve as a guide for effective comprehension of the local black carbon pollution issues and the development of imminent ecological and environmental management strategies in the Haizhou Bay region.