Dissolved black carbon (DBC) is the water-soluble fraction of the black carbon continuum, being the key flux that connects two major black carbon pools:the soils and the ocean sediments. DBC is also an important component of the dissolved organic matter pool. It has rich aromatic clusters and oxygen-containing functional groups including carboxyl, hydroxyl, and carbonyl groups. DBC plays an important role in the sorption and environmental transformation of pollutants. Thus, research on the biogeochemical behavior of DBC is key to the understanding of the global carbon cycle as well as the environmental fate and impact of pollutants. The present paper reviews the previous studies on the environmental processes of DBC. The discussion covers the qualitative and quantitative analytical methods of DBC, its spatiotemporal distribution, its structural characteristics and environmental transformation, as well as its impacts on the sorption, redox transformation and photo transformation of pollutants in the environments. Then the new research directions addressing current knowledge gaps are proposed.
Contents
1 Introduction
2 Analytical methods and the spatiotemporal distribution of DBC
2.1 Qualitative and quantitative analytical methods for DBC
2.2 Spatiotemporal distribution of DBC
3 Structural characteristics and environmental transformation of DBC
3.1 Structural characteristics of DBC
3.2 Environmental transformation of DBC
4 Impacts of DBC on the environmental behavior of pollutants
4.1 Impacts of DBC on the sorption behavior of pollutants
4.2 Impacts of DBC on the redox reactions of pollutants
4.3 Impacts of DBC on the photoconversion reactions of pollutants
5 Conclusion