Halogenation processes linked to red wood ant nests (Formica spp.) and tectonics

• Published in: Journal of atmospheric chemistry Vol. 74; no. 2; pp. 261 - 281
• Main Authors: Berberich, Gabriele M., Sattler, Tobias, Klimetzek, Dietrich, Benk, Simon A., Berberich, Martin B., Polag, Daniela, Schöler, Heinz Friedrich, Atlas, Elliot
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.06.2017; Springer; Springer Nature B.V
• Subjects: Alkanes; Area; Atmospheric Protection/Air Quality Control/Air Pollution; Atmospheric Sciences; Bioindicators; Biological indicators; Carbon dioxide; Chloroform; Degassing; Earth; Earth and Environmental Science; Earth Sciences; Earth tides; Earthquakes; Fault lines; Fault zones; Forest soils; Gas sampling; Gases; Geochemical cycle; Geochemical cycles; Geological faults; Halocarbons; Halogenation; Hot spots (geology); Indicator organisms; Indicator species; Limonene; Nests; New records; Nocturnal variations; Organic soils; Organohalogen compounds; Procedures; Seismic activity; Seismology; Soil; Soil chemistry; Soil gas; Soil gases; Soil investigations; Tectonics; Tides; Tracer gas; Tracers; Tracers (Biology); Trihalomethanes; Wood; CHCl; Seismically active area; H; Organohalogens; Soil gas; Red wood ants; O; Fault zone tracer gas
• ISSN: 0167-7764; 1573-0662
• DOI: 10.1007/s10874-016-9358-0

We investigated and evaluated the occurrence of fault zone tracer gases (CO 2 , He, Rn), volatile organohalogens (CH 3 Cl, CHCl 3 , CHBr 3 ), alkanes and limonene in soil and nest gases of red wood ants (RWA) in comparison to ambient air, in a seismically active area. In this new approach, we compared RWA-free areas to RWA-areas by combining different investigation and analytical methods. In soil gas, the fault zone tracer gas Rn was surprisingly highly correlated to limonene, suggesting a combination of biotic production of limonene and abiotic degassing of Rn in a seismically active area; moderate correlations were found with trihalomethanes and other halocarbons. In RWA nests a variety of elevated concentrations of haloforms were found, while remaining below the atmospheric background values in RWA-free areas. The evidence of CHCl 3 in RWA nests is the first record. Its average concentrations in nests of F. rufa and F. polyctena were up to 3 fold higher than atmospheric background and up to 28–70 fold higher compared to e.g. volcanic emissions being considered as one of its main geogenic sources. Thus, RWA nests could possibly be an additional source for CHCl 3 liberation. Consequently, apart from RWA being bioindicators for seismically active degassing faults, they might also be used as bioindicators for CHCl 3 formation in forest soils. Although we cannot yet differentiate between a geogenic/abiotic and a biotic formation. RWA nests will have to be reconsidered for halocarbon formation in future quantifications of geochemical cycles at global scale, since they impact organic soil chemistry through biotic and/or abiotic pathways. Therefore, further larger-scale research in different tectonic settings but also in well-known CHCl 3 “hot spot” study areas such as the Klosterhede area (Denmark) should focus directly on gas sampling from confirmed active fault systems. Nests of other ant species should be addressed to compare seasonal, diurnal and nocturnal variations of degassing procedures in relation to earth tides, different geologic settings, and tectonic events such as earthquakes and on quantifying the fluxes to the atmosphere.