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Student essay: Energy and New England history

Posted by Arjendu on June 4, 2016

Sally Donovan

Soil, Ecology, and History: 19th Century Energy Production in New England

Charcoal production played an important role in shaping settlement and industry in 19th century New England. As new fertile land was discovered out west, the agricultural industry migrated out of New England, leaving many agricultural settlements desperate for new industry. During this time, wood charcoal production replaced agriculture as the new industry of New England. The driving force behind this industry was iron. Wood charcoal was used in coal blast furnaces to produce iron, an important resource in the Civil War as well as westward expansion and industrialization. From a historical perspective, one can see how the demand for energy played an important role in shaping the post-agricultural development of 19th century New England. Furthermore, remnants of this industry are still prevalent today. In 2015 LiDAR analysis located 20,500 relic charcoal hearths in Litchfield County (Johnson et al., 2015). Litchfield Country, a region in the Northwest corner of Connecticut, measures196 km2. Considering this, it is likely there are thousands of undocumented relic hearths scattering the landscape of New England. Given the abundance of hearths, researchers are beginning to look into the environmental impacts of these hearths. While production sites were abandoned over 100 years ago, new studies are finding charcoal hearths continue to impact the region’s soil geochemistry and forest ecology today.

To produce charcoal, local timber was harvested and gathered in hearth sites. These hearths, which measured approximately 150 m2 in size, were filled with 25 to 50 cords (90-180 m3) of wood, covered in soil, and fired at temperatures reaching 450 degrees Celsius (Young et al. 1996). Then, over the course of 14 days, the wood was slowly carbonized to charcoal. During carbonization, the wood was dried and heated until it began to spontaneously break down. This produced charcoal and water vapor, methanol, acetic acid, and other complex chemicals, which are released as gas in the form of hydrogen, carbon monoxide, and carbon dioxide. These outputs, in combination with prolonged periods of heat, created a cycle of repetitive disturbances that damaged the local soil environment. Of these disturbances, previous studies (Hart et al. 2008; Gomez-Luna et al. 2009; Tryon 1948) found high amounts of charcoal inputs had an especially significant impact on the local soil environment, resulting in considerable long-term alterations to soil chemistry and morphology. For example, in a study analyzing relic charcoal hearths in the Pennsylvania, Young et al. (2006) reported significant differences in soil calcium concentrations, pH, and percent carbon between hearth and adjacent soils. Furthermore, in a study assessing hearths in southwestern Ethiopia, Nigussie and Kissi (2011) found charcoal residues left on hearth sites increased cation exchange capacity and exchangeable bases as well as elevated levels of total nitrogen and available phosphorus. In Ghana, Oguntunde and Fosu (2004) reported organic carbon and total nitrogen decreased on hearth soils.

The story of charcoal production in New England is one that is not usually told from the perspective of energy. However, the demand for energy was the driving force behind a long line of other developments. As a result of charcoal production, the region’s economy and industry flourished, the population increased, and the end product, iron, played a crucial role in the Civil War and westward expansion. Furthermore, the demand for energy played an important role in shaping New England’s forest ecology, an additional topic not traditionally linked to energy. Similar to many energy extraction methods today, charcoal production supplied a temporary boost the region’s economic and industrial development, however this process has left a lasting legacy effect on the production site environment.

Gomez-Luna, B. E., Rivera-Mosqueda, M. C., Dendooven, L., Vazquez-Marrufo, G., and Olade-Portugal, V., 2009, Charcoal production at kiln sites affects C and N dynamics and associated soil microorganisms in Quercus spp. temperate forests of central Mexico: Applied Soil Ecology, v. 41, no. 1, p. 50-58.
Hart, J. L., Van De Gevel, S. L., Mann, D. F., and Clatterbuck, W. K., 2008, Legacy of charcoaling in a Western Highland Rim forest in Tennessee: American Midland Naturalist, v. 159, no. 1, p. 238-250.
Johnson, K., Ouimet, W. and Raslan, Z., 2015, Geospatial and Lidar­based analysis of 18th to early 20th century timber harvesting and charcoal production in Southern New England. Geological Society of America Northeastern Section Meeting. Breton Woods, NH.
Nigussie, A., and Kissi, E., 2011. Effect of charcoal production on soil properties in southwestern Ethiopia: Middle-East Journal of Scientific Research, v. 9, no. 6, p. 807-813.
Oguntunde, P. G., Fosu, M., Ajayi, A. E., and van de Giesen, N., 2004, Effects of charcoal production on maize yield, chemical properties and texture of soil: Biology and Fertility of Soils, v. 39, no. 4, p. 295-299.
Tryon, E. H., 1948, Effect of charcoal on certain physical, chemical, and biological properties of forest soils: Ecological Monographs, v. 18, no. 1, p. 81-115.
Young, M. J., Johnson, J. E., and Abrams, M. D., 1996, Vegetative and edaphic characteristics on relic charcoal hearths in the Appalachian mountains: Vegetatio, v. 125, no. 1, p. 43-50.


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