Table Of ContentFOREST GROWTH RESPONSES TO
THE POLLUTION CLIMATE OF
THE 21st CENTURY
Forest Growth Responses to
the Pollution Climate of
the 21st Century
Edited by
LUCY J. SHEPPARD
and
J. NEIL CAPE
Institute of Terrestrial Ecology,
Edinburgh, Scotland,
United Kingdom
Reprinted from Water, Air, and Soil Pollution 116:
SPRINGER-SCIENCE+BUSINESS MEDIA. B.V.
A C.I.P. Catalogue record for this book is available from the Library of Congress.
ISBN 978-90-481-5328-2 ISBN 978-94-017-1578-2 (eBook)
DOI 10.1007/978-94-017-1578-2
Printed on acid-free paper
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© 1999 Springer Science+Business Media Dordrecht
Originally published by Kluwer Academic Publishers in 1999
Softcover reprint of the hardcover I st edition 1999
No part of the material protected by this copyright notice may be reproduced
or utilized in any form or by any means, electronic or mechanical,
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TABLE OF CONTENTS
Preface
Acknowledgements 3
D. FOWLER, J.N. CAPE, M. COYLE, C. FLECHARD, J. KUYLENSTIERNA, K. HICKS,
D. DERWENT, C. JOHNSON and D. STEVENSON , The Global Exposure of
Forests to Air Pollutants 5-32
H. SPIECKER 'Overview of Recent Growth Trends in European Forests 33-46
H. RENNENBERG and A. GESSLER' Consequences of N Deposition to Forest Ecosys
tems - Recent Results and Future Research Needs 47-64
B.A. EMMETT' The Impact of Nitrogen on Forest Soils and Feedbacks on Tree Growth 65-74
M.F. HOVMAND and J. BILLE-HANSSEN' Atmospheric Input to Danish Spruce Forests
and Effects on Soil Acidification and Forest Growth Based on 12 Years
Measurements 75-88
U. SKIBA, L.J. SHEPPARD, C.E.R PITCAIRN, S. VAN DIJK and M.J. ROSSALL , The
Effect of N Decomposition on Nitrous Oxide and Nitric Oxide Emissions from
Temperate Forest Soils 89-98
W. FLOCKIGER and S. BRAUN' Nitrogen and Its Effect on Growth, Nutrient Status and
Parasite Attacks in Beech and Norway Spruce 99-110
M. CARNOL, P. CUDLIN and P. INESON 'Impacts of (NH4)2S04 Deposition on Norway
Spruce (Picea Abies [L.] Karst) Roots 111-120
T. STASZEWSKI, S. GODZIK, P. KUBIESA and J. SZDZUJ , Fate of Nitrogen Compounds
Deposited to Spruce (Picea Abies Karst.) and Pine (Pinus Silvestris L.) Forests
Located in Different Air Pollution and Climatic Conditions 121-127
P. SCHLEPPI, I. BUCHER-WALLIN, R SIEGWOLF, M. SAURER, N. MULLER and J.B.
BUCHER' Simulation of Increased Nitrogen Deposition to a Montane Forest
Ecosystem: Partitioning of the Added 15N 129-134
J. WDLLECKE, B. MONZENBERGER and RF. HOTTL' Some Effects of N on Ectomyc
orrhizal Diversity of Scots Pine (Pinus Sylvestris L.) in Northeastern Germany 135-140
A. BYTNEROWICZ, S. GODZIK, M. POTH, I. ANDERSON, J. SZDZUJ, C. TOBIAS, S.
MACKO, P. KUBIESA, T. STASZEWSKI and M. FENN' Chemical Composition
of Air, Soil and Vegetation in Forests of the Silesian Beskid Mountains, Poland 141-150
S. McLAUGHLIN and K. PERCY' Forest Health in North America: Some Perspectives on
Actual and Potential Roles of Climate and Air Pollution 151-197
R MATYSSEK and J.L. INNES' Ozone - A Risk Factor for Trees and Forests in Europe? 199-226
J.M. SKELLY, J.L. INNES, J.E. SAVAGE, K.R. SNYDER, D. VANDERHEYDEN, J. ZHANG
and M.J. SANZ' Observation and Confirmation of Foliar Ozone Symptoms of
Native Plant Species of Switzerland and Southern Spain 227-234
N.E. GRULKE and L. BALDUMAN / Deciduous Conifers: High N Deposition and 03
Exposure Effects on Growth and Biomass Allocation in Ponderosa Pine 235-248
M. TAUSZ, A. BYTNEROWICZ, W. WEIDNER, M.J. ARBAUGH, P. PADGETT and D.
G RI LLI Changes in Free-Radical Scavengers Describe the Susceptibility of Pinus
Ponderosa to Ozone in Southern Californian Forests 249-254
A. CHAPPELKA, G. SOMERS and J. RENFRO' Visible Ozone Injury on Forest Trees in
Great Smoky Mountains National Park, USA 255-260
A. CHAPPELKA, J. SKELLY, G. SOMERS, J. RENFRO and E. HILDEBRAND / Mature
Black Cherry Used as a Bioindicator of Ozone Injury 261-266
E. GRAVANO, M. FERRETTI, F. BUSSOTTI and P. GROSSONI' Foliar Symptoms and
Growth Reduction of Ailanthus altissima Desf. in an Area with High Ozone and
Acidic Deposition in Italy 267-272
R. INCLAN, A. RIBAS, J. PENUELAS and B.S. GIMENO / The Relative Sensitivity of
Different Mediterranean Plant Species to Ozone Exposure 273-277
RL. HEATH / Biochemical Processes in an Ecosystem: How Should They Be Measured? 279-298
M.S.J. BROADMEADOW, J. HEATH and T.J. RANDLE / Environmental Limitations to
03 Uptake - Some Key Results from Young Trees Growing at Elevated C02
Concentrations 299-310
D.F. KARNOSKY, B. MANKOVSKA, K. PERCY, A.E. DICKSON, G.K. PODILA, J. SOBER,
A. NOORMETS, G. HENDREY, M.D. COLEMAN, M. KUBISKE, K.S. PREGITZER
and J.G. ISEBRANDS / Effects of Tropospheric 03 on Trembling Aspen and
Interaction with C02: Results from an 03-Gradient and a Face Experiment 311-322
M.S. GONTHARDT-GOERG, S. MAURER, J. BOLLIGER, AJ. CLARK, W. LANDOLT and
J.B. BUCHER/ Responses of Young Trees (Five Species in a Chamber Exposure)
to Near-Ambient Ozone Concentrations 323-332
S. MANNINEN, D. LE THIEC, C. ROSE, G. NOURRISSON, F. RADNAI, J.P. GARREC and
S. HUTTUNEN / Pigment Concentrations and Ratios of Aleppo Pine Seedlings
Exposed to Ozone 333-338
A.M. COX and J.w. MALCOLM / Passive Ozone Monitoring for Forest Health Assessment 339-344
G. GEROSA, F. SPINAZZI and A BALLARIN DENTI / Tropospheric Ozone in Alpine
Forest Sites: Air Quality Monitoring and Statistical Data Analysis 345-350
M. FERRETTI, I. BONINI, F. BUSSOTTI, C. CELESTI, E. CENNI, A. CHIARUCCI,
A COZZI, V. DE DOMINICIS, P. GROSSONI and C. LEONZIO / Short-Term
Changes of Response Indicators of Ecosystem Status in Broadleaved Forests in
Tuscany (Central Italy) 351-356
S. BRAUN, B. RIHM, C. SCHINDLER and W. FLOCKIGER / Growth of Mature Beech in
Relation to Ozone and Nitrogen Deposition: An Epidemiological Approach 357-364
M.V. KOZLOV and P. NIEMELA / Difference in Needle Length - A New and Objective
Indicator of Pollution Impact on Scots Pine (Pinus sylvestris) 365-370
M. FERRETTI, F. BUSSOTTI, E. CENNI and A COZZI/Implementation of Quality Assur-
ance Procedures in the Italian Programs of Forest Condition Monitoring 371-376
F. BATIC, P. KALAN, H. KRAIGHER, H. SIRCELJ, P. SIMONCIC, N. VIDERGAR-GORJUP
and B. TURK / Bioindication of Different Stresses in Forest Decline Studies in
Slovenia 377-382
G. THELIN, U. ROSENGREN-BRINCK and 8. NIHLGARD / Can Graphical Vector Analy-
sis be Used to Identify Micro Nutrient Deficiency? 383-388
J. NEIRYNCK and P. ROSKAMS / Relationships Between Crown Condition of Beech
(Fagus sylvatica L.) and Throughfall Chemistry 389-394
W. PRUS-GLOWACKI, A WOJNICKA-POLTORAK, J. OLEKSYN and P.B. REICH /Indus-
trial Pollutants Tend to Increase Genetic Diversity: Evidence from Field-Grown
European Scots Pine Populations 395-402
J.L.J. HOUPIS, P.D. ANDERSON, J.C. PUSHNIK and D.J. ANSCHEL / Among-
Provenance Variability of Gas Exchange and Growth in Response to Long-Term
Elevated C02 Exposure 403-412
J.C. PUSHNIK, D. GARCIA-IBILCIETA, S. BAUER, P.D. ANDERSON, J. BELL and J.L.J.
HOUPIS / Biochemical Responses and Altered Genetic Expression Patterns in
Ponderosa Pine (Pinus ponderosa Doug ex P. Laws) Grown under Elevated C02 413-422
A WONISCH, M. TAUSZ, M. MOLLER, W. WEIDNER, L.J. DE KOK and D. GRILL /
Treatment of Young Spruce Shoots with S02 and H2S: Effects on Fine Root
Chromosomes in Relation to Changes in the Thiol Content and Redox State 423-428
D.C. GORDON and K.E. PERCY / Effect of UV-B Dose on Biosynthesis of Epicuticular
Waxes in Blue Spruce (Picea Pungens Engelmann.) Primary Needles: Prelimi-
nary Investigation 429-436
A. AUGUSTAITIS / A New Imitative Model to Predict the Impact of Air Pollutants on Scots
Pine Health and Radial Increment 437-442
K. PERCY, J. BUCHER, J. CAPE, M. FERRETTI, A. HEATH, H.E. JONES, D. KARNOSKY,
A. MATYSSEK, G. MULLER-STARCK, E. PAOLETTI, U. ROSENGREN-BRINCK,
L. SHEPPARD, J. SKELLY and G. WEETMAN / State of Science and Knowledge
Gaps with Respect to Air Pollution Impacts on Forests: Reports from Concurrent
IUFRO 7.04.00 Working Party Sessions 443-448
PREFACE
This Special Issue of Water, Air and Soil Pollution offers contributions from the
18th IUFRO workshop on Air Pollution Stress, Forest Responses to the Pollution
Climate of the 21st Century held in Edinburgh, Scotland, from September 21 to
23,1998.
The meeting was held under the auspices of IUFRO, Research Group 7.04.00
chaired by Dr Kevin Percy of Canada. A new session structure was adopted to
stimulate activity within the six working parties and a brief resume of these is
presented at the front of this volume. The two, one-day plenary sessions were
devoted to the two important air pollution issues, nitrogen deposition and ozone.
Invited papers were augmented by a large and excellent contribution of poster
papers. The final day comprised parallel Working Party Sessions with pre
arranged speakers to stimulate discussions. One hundred and thirty one scientists
attended, representing 20 countries and 7 IUFRO regions: Northern Europe,
Central Europe, Eastern Europe, Mediterranean, North America, Asia and the
Western Pacific.
Lucy Sheppard
David Fowler
Water, Air, and Soil Pollution 116: 1, 1999.
© 1999 Kluwer Academic Publishers.
ACKNOWLEDGEMENTS
The Edinburgh IUFRO meeting was organised by a few dedicated people and the
goodwill of the IUFRO air pollution specialists. We should like to thank
members of the Institute of Terrestrial Ecology, especially Kate Potter and Lucy
Douglas, who between them undertook the compilation of the proceedings, all
the administrative arrangements and the seemingly endless reformatting of
papers. Prior to and since the meeting Davis Innes and Lisa Murphy have
provided unstinting support, performing any task asked of them. Tom Murray
produced the flier and members of the pollution group - Ian Leith, Alan
Crossley, Carole Pitcairn, Ute Skiba, Frank Harvey, Alastair Dunster and our
station director Melvin Cannell - gave up their Sunday afternoon to show nearly
70 visitors round the acid mist field fumigation experiment at Deepsyke and the
open top chamber facility at Bush. The weather was outstanding - it was
Edinburgh's hottest day in 1998! The UK forestry commission assisted with the
organisation of the meeting and the UK government, represented by Lord Sewell,
Minister of Forestry and Agriculture for Scotland, hosted an excellent reception
for the meeting, in Edinburgh Castle. Visitors were treated to a private viewing
of the Scottish Crown Jewels.
Over 60 manuscripts were submitted and reviewed, and the 41, which appear
here, survived a rigorous reviewing and rewriting period. We are very grateful to
the authors who responded politely to the requests for redrafts of their papers. We
are also very grateful to all our reviewers listed at the end of these proceedings
and their institutions, who gave of their time and effort.
The front cover of the hardbound book was produced by Zoe Fowler and Mhairi
Coyle.
Mariette de Jong and Astrid Zandee of the staff of Kluwer Academic Publishers
have been particularly helpful, responding rapidly to all requests for guidance.
Our respective home institution, the Institute of Terrestrial Ecology, has
supported us throughout this initiative. The meeting was entirely self-financing.
Lucy Sheppard
Neil Cape
David Fowler
Water, Air, and Soil Pollution 116: 3, 1999.
© 1999 Kluwer Academic Publishers.
THE GLOBAL EXPOSURE OF FORESTS TO AIR POLLUTANTS
DAVID FOWLER!, J. NEIL CAPE\ MHAIRI COYLE!, CHRIS FLECHARD\
JOHAN KUYLENSTIERNA2, KEVIN HICKS2, DICK DERWENT3, COLIN JOHNSON3 AND DAVID
STEVENSON3
llnstitute of Terrestrial Ecology, Edinburgh Research Station, Bush estate, Penicuik,
Midlothian EH26 OQB. TE Edinburgh, UK; 2S tockholm Environment Institute,
University of York, UK; 3Meteorological Office, London Road, Bracknell, Berks. RG12
2SYUK
(Received 9 April 1999; accepted 23 April 1999)
Abstract: The tall, aerodynamically rough surfaces of forests provide for the efficient exchange of heat and
momentum between terrestrial surfaces and the atmosphere. The same properties of forests also provide for
large potential rates of deposition of pollutant gases, aerosols and cloud droplets. For some reactive pollutant
gases, including S02, HN03 and NH3. rates of deposition may be large and substantially larger than onto
shorter vegetation and is the cause of the so called ''filtering effect" of forest canopies. Pollutant inputs to
moorland and forest have been compared using measured ambient concentrations from an unpolluted site in
southern Scotland and a more polluted site in south eastern Germany. The inputs of S and N to forest at the
Scottish site exceed moorland by 16% and 31% respectively with inputs of 7.3 kg S ha'! yand 10.6 kg N ha'!
y'!. At the continental site inputs to the forest were 43% and 48% larger than over moorland for S and N
deposition with totals of 53.6 kg S ha'! y"! and 69.5 kg N ha'! y'! respectively.
The inputs of acidity to global forests show that in 1985 most of the areas receiving> 1 kg H+ ha'! y"1 as S
are in the temperate latitudes, with 8% of total global forest exceeding this threshold. By 2050, 17% of global
forest will be receiving> 1 kg H-I ha·1 as S and most of the increase is in tropical and sub-tropical countries.
Forests throughout the world are also exposed to elevated concentrations of ozone. Taking 60 ppb 03 as a
concentration likely to be phytotoxic to sensitive forest species, a global model has been used to simulate the
global exposure of forests to potentially phytotoxic 03 concentrations for the years 1860, 1950, 1970, 1990
and 2100. The model shows no exposure to concentratiol)s in excess of 60 ppb in 1860, and of the 6% of
global forest exposed to concentrations> 60 ppb in 1950,75% were in temperate latitudes and 25% in the
tropics. By 1990 24% of global forest is exposed to 03 concentrates> 60 ppb, and this increases to almost
50% of global forest by 2100. While the uncertainty in the future pollution climate of global forest is
considerable, the likely impact of 03 and acid deposition is even more difficult to assess because of
interactions between these pollutants and substantial changes in ambient CO2 concentration, N deposition and
climate over the same period, but the effects are unlikely to be beneficial overall.
Keywords: acid deposition, ozone, forests, nitrogen deposition, pollution climate.
1. Introdnction
The major regional pollutants associated with acidic deposition (oxidised sulphur and
nitrogen compounds and reduced nitrogen, and the photochemical oxidant (03)
represent a threat to a wide range of ecosystems including agricultural crops, wetlands
and heathland vegetation. However, much of the interest in pollutant effects during the
last three decades has been focussed on forests. Examples include the role of air
pollutants in the decline in health of Ponderosa Pine in Southern California (Miller et
Water, Air, and Soil Pollution 116: 5-32, 1999.
© 1999 Kluwer Academic Publishers.
6 D. FOWLERET AL.
al., 1963), the dieback of high elevation forests in the Appalachian mountains of
Eastern North America (Eager and Adams, 1992) and the 'new type' offorest decline in
Germany and other areas of central Europe (Schultze and Freer-Smith, 1991). More
recently, observations of increased rates of growth of European forests have focussed on
the role of elevated CO2 concentrations and the deposition of fixed nitrogen (Cannell et
al.1997; Spiecker et al., 1996; Thornley et al., 1991), both oxidised (NOx) and reduced
(NH
x)·
Why should forests become such a clear focus of interest in these pollution
problems? Is it simply a consequence of their abundance as land cover or size relative to
other vegetation in the non-agricultural landscape and their importance for amenity, or,
are there factors, which predispose forests to the influence, positive or negative of air
pollutants?
In this paper, the properties of forests as sinks for the major gaseous and particulate
pollutants are described and contrasted with shorter vegetation. In this way one of the
major characteristics of forests, their aerodynamic interaction with the atmosphere, is
highlighted as an important contributor to their sensitivity to the presence of reactive air
pollutants. The current and projected trends in emissions of acidifying pollutant and the
presence of photochemical oxidants are then used to quantify the spatial and temporal
trends in pollutant exposure globally.
2. Forests and the Atmosphere
The exchange of mass, sensible heat and momentum between vegetation and the
atmosphere is effected by turbulent transfer, molecular processes only becoming
«<
important very close 1mm) to terrestrial surfaces. The turbulence generated within
the surface layers of the atmosphere occurs as a consequence of frictional drag at the
earth's surface and forests, among all natural land cover classes, generate the greatest
frictional drag at the surface. Forests are therefore aerodynamically rough surfaces with
rates of turbulent exchange between the atmosphere and forests larger by an order of
magnitude or more than those over grassland.
The rates of exchange of mass, energy and momentum between forests and the
atmosphere are discussed in detail by Jarvis et at. (1975) and Thom (1975). The extent
to which the larger rates of turbulent transfer above forests lead to larger inputs of
pollutants to forests than other vegetation is determined by physical and chemical
processes at the foliar surfaces, and within the viscous boundary layer close to foliage.
Thus the physical and chemical properties of the pollutants interact strongly with the
properties of forests to determine rates of exchange.
3. The Pollutants
The pollutants occur as gases, S02, NO, N02, RN03, NH3, 03, as aerosol particles
mainly in the size range
0.1 to 1.0 ~m (diameter) sol-, N03-, NH/, W
0.1 to 0.5 ~m (diameter) heavy metals (e.g. Pb, Cd, Zn, Cu)
1.0 to 3.0 ~m (diameter) base cations Ca2+, Mg2+
THE GLOBAL EXPOSURE OF FORESTS TO AIR POLLUTANTS 7
and as cloud droplets in the range 3 11m to 20 11m in diameter, containing the major ions
(SOl, N03-NH/, W, cr, Na+, Ca2+, Mg2+).
Generalising the properties of forests necessarily conceals the variability between
forests of different species composition and climates. The alternative, of describing the
aerodynamic properties of a range of tree species and canopy structures, is outside the
scope of this paper. Furthermore, the extent of published literature to provide the basis
for such an exercise is limited to relatively few species.
TABLE I
Potential effects of forests on deposition fluxes
Moorland Forest % Increase
ForestIMoor
Canopy height h(m) 0.15 10
Zero plane displacement d(m) 0.1 7
Roughness length z,,(m) 0.01 1.0
Friction velocity u. (m S-I) 0.32 0.82 156%
Momentum flux t (N m-z) 131 840 541%
Maximum deposition velocity V max SOZ (mm S·I) 18.6 35.1 89%
forS02
Maximum deposition velocity V max NOz (mm S-I) 20.0 43.5 118%
forNOz
Maximum deposition velocity Vmax NH3 (mm S-I) 21.4 55.5 160%
forNH3
In describing and contrasting the micrometeorology of temperate and tropical forests
Shuttleworth (1989) showed broad similarities in the rates of exchange of water and
energy of boreal conifer forest and tropical rainforests. The forests have had to adapt to
common problems of limited water supply and very large potential rates of water loss
despite the very different architecture of the forest canopies and the climatologies of
these regions. The same processes which create the potential for large rates of exchange
of momentum, water and sensible heat also influence the deposition of pollutants.
4. Potential deposition rates of pollutants on forests
The extent to which these generalisations apply to the deposition of pollutants on forests
varies with the physical and chemical forms of the pollutant. It is therefore necessary
