Japan Geoscience Union Meeting 2016

Presentation information

Oral

Symbol M (Multidisciplinary and Interdisciplinary) » M-IS Intersection

[M-IS06] Biogeochemistry

Sun. May 22, 2016 1:45 PM - 3:15 PM A03 (APA HOTEL&RESORT TOKYO BAY MAKUHARI)

Convener:*Muneoki Yoh(Tokyo University of Agriculture and Technology), Hideaki Shibata(Field Science Center fot Northern Biosphere, Hokkaido University), Naohiko Ohkouchi(Japan Agency for Marine-Earth Science and Technology), Youhei Yamashita(Faculty of Environmental Earth Science, Hokkaido University), Chair:Yoshiyuki Inagaki(Forestry and Forest Products Research Institute), Kazumichi Fujii(Forestry and Forest Products Research Institute), Rota Wagai(National Institute for Agro-Environmental Sciences, Carbon & Nutrient Cycling Division), Kazuya Nishina(National Institute for Enviromental Studies)

1:45 PM - 2:00 PM

[MIS06-13] Damages of the world trees caused by sulfuric acid of the air pollutant

*Teiko Omori1 (1.The Faculty of Science Toho University)

Keywords:air pollutant, sulfuric acid, charcoal

Air pollutants discharge sulfur oxides in proportion to the emissions of carbon dioxide resulting from combustion of fossil fuels. Sulfur oxides become sulfuric acid and are accumulated in the air unless they fall on the ground with the rain or snow. Sulfate ion was found in the ice core of 1785 in Greenland1), and the fossil fuel has been burning for 230 years. Sulfuric acid in the air sticks to the trees that stand in the areas where the polar vortex in the Southern Hemisphere and the westerlies in the Northern Hemisphere pass through, and then it is dropped to the ground with the rain. Sulfuric acid transforms the metal component of the soil (Al, Fe) to a soluble compound of sulfate, and the metal ions dissolved in rainwater are absorbed by the trees. Following the principle that coexisting substances become the compound with the strongest bonding power, the metal ions take the phosphoric acid from the phosphate compound in the trees and become an insoluble metal phosphate compound. Trees become the same phenomenon as the shortage of phosphoric acid and decline. Declined trees lose the resistance over damage by blight and harmful insects.
Beech and eucalyptus in Fuego Island in Argentina, at the southern tip of South Island of New Zealand, in Perth in Australia near the polar vortex in the Southern Hemisphere are completely destroyed. The westerlies in the Northern Hemisphere pass Japan and withered conifer and broad leaf trees, then travel beyond the Pacific Ocean and withered conifer trees in the southwest of British Columbia, Canada2). Westerlies that pass through the United States absorb additional sulfuric acid from the thermal power plant near the Great Lakes and withered conifer trees in the Adirondack district in the state of New York and go across the Atlantic Ocean and withered trees in Europe.
When charcoal is sprayed, the acid soil is neutralized with potassium compounds contained in charcoal and metal ions become hydroxides which can no longer be absorbed by trees and the phosphoric acid is protected. Potassium is an essential element of trees and it helps the growing of trees and the weakened trees recover. From this fact, we can prove that the damage of trees is due to the acidification of the soil with sulfuric acid of air pollutants3).
When pines weaken, the amount of pine resin decreases and tannin loses an insect repellent ability when it is combined with metal ions. As a result, it becomes easier for insects to get into trees and increase explosively.3)
References
1) Watanabe O., Motoyama H., Ushio S., and Morimoto S. (2003) Separate volume of Heredity,
No.17. 58-68.
2) “Climate Change” (2009) p.137 K.K.Kyodo News.
3) Omori T. and Iwasaki M. (2010) Wood Carbonization Research, 7, 3-11.