Open AccessThis article is
- freely available
Black Carbon’s Properties and Role in the Environment: A Comprehensive Review
Environmental Systems Program, Sierra Nevada Research Institute, University of California-Merced, 5200 N. Lake Road, Merced, CA 95343, USA
Northern Institute of Applied Carbon Science, Climate, Fire, & Carbon Cycle Science Research, Northern Research Station, USDA Forest Service, 410 MacInnes Drive, Houghton, MI 49931, USA
* Author to whom correspondence should be addressed.
Received: 13 November 2009; Accepted: 7 January 2010 / Published: 15 January 2010
Abstract: Produced from incomplete combustion of biomass and fossil fuel in the absence of oxygen, black carbon (BC) is the collective term for a range of carbonaceous substances encompassing partly charred plant residues to highly graphitized soot. Depending on its form, condition of origin and storage (from the atmosphere to the geosphere), and surrounding environmental conditions, BC can influence the environment at local, regional and global scales in different ways. In this paper, we review and synthesize recent findings and discussions on the nature of these different forms of BC and their impacts, particularly in relation to pollution and climate change. We start by describing the different types of BCs and their mechanisms of formation. To elucidate their pollutant sorption properties, we present some models involving polycyclic aromatic hydrocarbons and organic carbon. Subsequently, we discuss the stability of BC in the environment, summarizing the results of studies that showed a lack of chemical degradation of BC in soil and those that exposed BC to severe oxidative reactions to degrade it. After a brief overview of BC extraction and measurement methods and BC use for source attribution studies, we reflect upon its significance in the environment, first by going over a theory that it could represent parts of what is called the ‘missing sink’ of carbon in global carbon cycle models. Elaborating upon the relationship of BC with polycyclic hydrocarbons, we show its significance for the sorption and transport of pollutants. A description of pulmonary-respiratory health effects of soot BC inhalation is followed by a discussion on its impact on climate and climate change. We explain how soot BC acts as a global warming agent through light (and heat) absorption and how it reduces the snow’s albedo and promotes its uncharacteristic thawing. On a more positive note, we conclude this review by illustrating recent observations and simulations of how pyrolytic processes can stabilize plant carbon stocks in the form of biochar BC that can sequester carbon and can help mitigate climate change, in addition to improving soil fertility.
Keywords: soil carbon sequestration; carbon budget; atmospheric pollution; polycyclic aromatic hydrocarbons; climate; biochar
Citations to this Article
Cite This Article
MDPI and ACS Style
Shrestha, G.; Traina, S.J.; Swanston, C.W. Black Carbon’s Properties and Role in the Environment: A Comprehensive Review. Sustainability 2010, 2, 294-320.
Shrestha G, Traina SJ, Swanston CW. Black Carbon’s Properties and Role in the Environment: A Comprehensive Review. Sustainability. 2010; 2(1):294-320.
Shrestha, Gyami; Traina, Samuel J.; Swanston, Christopher W. 2010. "Black Carbon’s Properties and Role in the Environment: A Comprehensive Review." Sustainability 2, no. 1: 294-320.