Effects of air pollution from road transport on growth and physiology of six transplanted bryophyte species.

Motor vehicles emit a cocktail of pollutants; however, little is known about the effects of these pollutants on bryophytes located in roadside habitats. Six bryophyte species were transplanted to either a woodland or a moorland site adjacent to a motorway, and were monitored over sevenmonths from autumn through to spring. All species showed an increase in one or more of the following near the motorway: growth, membrane leakage, chlorophyll concentration, and nitrogen concentration. The strongest effects were observed in the first 50-100 m from the motorway: this was consistent with the nitrogen dioxide pollution profile, which decreased to background levels at a distance of 100-125 m. It is hypothesised that motor vehicle pollution was responsible for the effects observed, and that nitrogen oxides had a key influence. The observed effects may lead to changes in vegetation composition with significant implications for nature conservation and management of roadside sites.

[1]  M. L. Pignata,et al.  Comparative biomonitoring of atmospheric quality in five zones of Córdoba city (Argentina) employing the transplanted lichen Usnea sp. , 1998 .

[2]  J. Ruuskanen,et al.  Airborne pollutants along a roadside: assessment using snow analyses and moss bags. , 1997, Environmental pollution.

[3]  L. Pearson.  Air pollution damage to cell membranes in lichens i. development of a simple monitoring test , 1985 .

[4]  Mike Ashmore,et al.  Ecological impacts of air pollution from road transport on local vegetation , 2007 .

[5]  A. Farmer,et al.  Seasonal variations in acidic pollutant inputs and their effects on the chemistry of stemflow, bark and epiphyte tissues in three oak woodlands in N.W. Britain , 1991 .

[6]  J. Cape,et al.  Vegetation composition of roadside verges in Scotland: the effects of nitrogen deposition, disturbance and management. , 2005, Environmental pollution.

[7]  S. Bakken.  Effects of nitrogen supply and irradiance on growth and nitrogen status in the moss Dicranum majus from differently polluted areas , 1995 .

[8]  P. Martikainen,et al.  Ozone effects on Sphagnum mosses, carbon dioxide exchange and methane emission in boreal peatland microcosms. , 2002, The Science of the total environment.

[9]  G. Cragg,et al.  Mosses, Liverworts, and Hornworts Screened for Antitumor Agents , 1986, Economic Botany.

[10]  S. Caporn,et al.  Responses of four Sphagnum species to acute ozone fumigation , 1996 .

[11]  J. P. Grime,et al.  Methods in comparative plant ecology : a laboratory manual , 1993 .

[12]  D. Thompson,et al.  Regional and historical variation in the nitrogen content of Racomitrium lanuginosum in Britain in relation to atmospheric nitrogen deposition. , 1994, Environmental pollution.

[13]  J. W. Bates.  Bryology for the Twenty-first Century , 1998 .

[14]  M. Seaward,et al.  Correlation between the nitrogen concentration of two epiphytic lichens and the traffic density in an urban area. , 2003, Environmental pollution.

[15]  J. Oksanen,et al.  Membrane permeability response of lichen Bryoria fuscescens to wet deposited heavy metals and acid rain , 1999 .

[16]  D. Hawksworth.  The changing wildlife of Great Britain and Ireland , 2003 .

[17]  S. Bakken.  Regional variation in nitrogen, protein and chlorophyll concentration in Dicranum majus — a reciprocal transplantation experiment , 1995 .

[18]  A. Fischer,et al.  Changed vegetation composition in coniferous forests near to motorways in Southern Germany: the effects of traffic-born pollution. , 2006, Environmental pollution.

[19]  L. E. Anderson,et al.  The Biology of Mosses , 1982 .

[20]  P. Angold.  The impact of a road upon adjacent heathland vegetation : effects on plant species composition , 1997 .

[21]  A. Rutter,et al.  The salinity of motorway soils. II: Distance from the carriageway and other sources of local variation in salinity , 1986 .

[22]  John A. Lee,et al.  Effects of nitrogen oxides on nitrate assimilation in bryophytes , 1992 .

[23]  L. Gustafsson,et al.  Retention of trees at final harvest—evaluation of a conservation technique using epiphytic bryophyte and lichen transplants , 1999 .

[24]  I. H. Rorison,et al.  Chemical Analysis of Ecological Materials. , 1974 .

[25]  P. Kuiper,et al.  Elevated atmospheric CO2 and increased nitrogen deposition: effects on C and N metabolism and growth of the peat moss Sphagnum recurvum P. Beauv. var. mucronatum (Russ.) Warnst , 2000 .

[26]  T. Rambo,et al.  Using Transplants to Measure Accumulation Rates of Epiphytic Bryophytes In Forests of Western Oregon , 2001 .

[27]  S. Bell,et al.  Effects of rural roadside levels of nitrogen dioxide on Polytrichum formosum Hedw. , 1992, Environmental pollution.

[28]  J. Thompson,et al.  Outbreaks of insect herbivores on plants along motorways in the United Kingdom. , 1980 .

[29]  J. B. Kenworthy,et al.  Chemical Analysis of Ecological Materials. , 1976 .

[30]  O. Gilbert.  BRYOPHYTES AS INDICATORS OF AIR POLLUTION IN THE TYNE VALLEY , 1968 .

[31]  D. Wells,et al.  Traffic exposure increases natural 15N and heavy metal concentrations in mosses , 2000 .

[32]  C. Preston,et al.  Evidence for the effects of atmospheric pollution on bryophytes from national and local recording , 1992 .

[33]  H. Walton,et al.  The Air Quality Strategy for England, Scotland, Wales and Northern Ireland , 2007 .

[34]  D. N. Rao,et al.  Effects of Sulphur Dioxide on Lichen and Moss Transplants , 1973 .

[35]  C. Mueller,et al.  Lichen physiology and air pollution: II. Statistical analysis of the correlation between SO2 , NO2 , NO and O3 , and chlorophyll content, net photosynthesis, sulphate uptake and protein synthesis of Parmelia sulcata Taylor. , 1990, The New phytologist.

[36]  A. Wellburn.  The Spectral Determination of Chlorophylls a and b, as well as Total Carotenoids, Using Various Solvents with Spectrophotometers of Different Resolution* , 1994 .

[37]  D. Fowler,et al.  The relationship between nitrogen deposition, species composition and foliar nitrogen concentrations in woodland flora in the vicinity of livestock farms , 1998 .

[38]  R. Orliński.  Multipoint moss passive samplers assessment of urban airborne polycyclic aromatic hydrocarbons: concentrations profile and distribution along Warsaw main streets. , 2002, Chemosphere.

[39]  J. Cape,et al.  Growth and tissue nitrogen of epiphytic Atlantic bryophytes: effects of increased and decreased atmospheric N deposition , 2004 .