ENVIRONMENTAL MICROBIOLOGY Relationship of Atmospheric Pollution Characterized by Gas (NO 2 ) and Particles (PM10) to Microbial Communities Living in Bryophytes at Three Differently Polluted Sites (Rural, Urban, and Industrial) Caroline Meyer & Daniel Gilbert & André Gaudry & Marielle Franchi & Hung Nguyen-Viet & Juliette Fabure & Nadine Bernard Received: 10 August 2009 / Accepted: 12 August 2009 # Springer Science + Business Media, LLC 2009 Abstract Atmospheric pollution has become a major problem for modern societies owing to its fatal effects on both human health and ecosystems. We studied the relationships of nitrogen dioxide atmospheric pollution and metal trace elements contained in atmospheric particles which were accumulated in bryophytes to microbial communities of bryophytes at three differently polluted sites in France (rural, urban, and industrial) over an 8- month period. The analysis of bryophytes showed an accumulation of Cr and Fe at the rural site; Cr, Fe, Zn, Cu, Al, and Pb at the urban site; and Fe, Cr, Pb, Al, Sr, Cu, and Zn at the industrial site. During this study, the structure of the microbial communities which is characterized by biomasses of microbial groups evolved differently accord- ing to the site. Microalgae, bacteria, rotifers, and testate amoebae biomasses were significantly higher in the rural site. Cyanobacteria biomass was significantly higher at the industrial site. Fungal and ciliate biomasses were signifi- cantly higher at the urban and industrial sites for the winter period and higher at the rural site for the spring period. The redundancy analysis showed that the physico-chemical variables ([NO 2 ], relative humidity, temperature, and site) and the trace elements which were accumulated in bryophytes ([Cu], [Sr], [Pb]) explained 69.3% of the variance in the microbial community data. Moreover, our results suggest that microbial communities are potential biomonitors of atmospheric pollution. Further research is needed to understand the causal relationship underlined by the observed patterns. Introduction In the last few years, atmospheric pollution has become a serious problem of society because of its drastic effects on both human health and ecosystems [7, 17, 30, 43]. Atmospheric environment is a mixture of gases and particles of mineral or organic origin. The types of atmospheric pollutants and the pollution levels depend on many factors, such as emission sources, physical condi- tions, and meteorological parameters. The concentrations of the principal atmospheric gas pollutants have been increas- ing due to the increase of anthropogenic sources like traffic and industry [4, 30]. For instance, nitrogen dioxide (NO 2 ) is C. Meyer (*) : N. Bernard Department of Chrono-Environment, UMR 6249, University of Franche-Comte, Place Leclerc, 25030 Besançon, France e-mail: caroline.meyer@univ-fcomte.fr D. Gilbert : M. Franchi Department of Chrono-Environment, UMR 6249, University of Franche-Comte, 4 place Tharradin, B.P. 71427, 25 211 Montbéliard Cedex, France A. Gaudry Groupe d’Analyses Elémentaires, Laboratoire Pierre Süe (cnrs/cea), CEA Saclay, 91191 Gif-sur-Yvette, France H. Nguyen-Viet Department of Public Health and Epidemiology, Swiss Tropical Institute, Socinstrasse 57, P.O Box, 4002 Basel, Switzerland J. Fabure Département de Botanique et de Cryptogamie, Faculté des Sciences Pharmaceutiques et Biologiques de Lille, B.P. 83, 59006 Lille Cedex, France Microb Ecol DOI 10.1007/s00248-009-9580-2