Professor Philip Wookey

| Publications in peer-reviewed international journals | Contributions to monographs |
|Other publications (not including conference abstracts or contract reports |

Publications in peer-reviewed international journals

• Hartley, I.P., Garnett, M.H., Sommerkorn, M., Hopkins, D.W., Fletcher, B.J., Sloan, V.L., Phoenix, G.K. and Wookey, P.A. (2012). A potential loss of carbon associated with greater plant growth in the European Arctic. Nature Climate Change.
  doi:10.1038/nclimate1575
• Kaarlejärvi, E., Baxter, R., Hofgaard, A., Hytteborn, H., Khitun, O., Molau, U., Sjögersten, S., Wookey, P.A. and Olofsson, J. (2012). Effects of Warming on Shrub Abundance and Chemistry Drive Ecosystem-Level Changes in a Forest–Tundra Ecotone. Ecosystems. doi:10.1007/s10021-012-9580-9
• Elmendorf, S.C., Henry, G.H.R., Hollister, R.D., Björk, R.G., Bjorkman, A.D., Callaghan, T.V., Collier, L.S., Cooper, E.J., Cornelissen, J.H.C., Day, T.A., Fosaa, A.M., Gould, W.A., Grétarsdóttir, J., Harte, J., Hermanutz, L., Hik, D.S., Hofgaard, A., Jarrad, F., Jónsdóttir, I.S., Keuper, F., Klanderud, K., Klein, J.A., Koh, S., Kudo, G., Lang, S.I., Loewen, V., May, J.L., Mercado, J., Michelsen, A., Molau, U., Myers-Smith, I.H., Oberbauer, S.F., Pieper, S., Post, E., Rixen, C., Robinson, C.H., Schmidt, N.M., Shaver, G.R., Stenström, A., Tolvanen, A., Totland, Ø., Troxler, T., Wahren, C.-H., Webber, P.J., Welker, J.M. and Wookey, P.A. (2012). Global assessment of experimental climate warming on tundra vegetation: heterogeneity over space and time. Ecology Letters, 15(2), 164–175.
  doi:10.1111/j.1461-0248.2011.01716.x
• Hartley, I.P., Hopkins, D.W., Sommerkorn, M. and Wookey, P.A. (2010). The response of organic matter mineralisation to nutrient and substrate additions in sub-arctic soils. Soil Biology & Biochemistry, 42(1), 92-100.
  doi:10.1016/j.soilbio.2009.10.004
• Post, E., Forchhammer, M.C., Bret-Harte, M.S., Callaghan, T.V., Christensen, T.R., Elberling, B., Fox, A.D., Gilg, O., Hik, D.S., Høye, T.T., Ims, R.A., Jeppesen, E., Klein, D.R., Madsen, J., McGuire, A.D., Rysgaard, S., Schindler, D.E., Stirling, I., Tamstorf, M.P., Tyler, N.J.C., van der Wal, R., Welker, J., Wookey, P.A., Schmidt, N.M. and Aastrup, P. (2009). Ecological Dynamics Across the Arctic Associated with Recent Climate Change. Science, 325(5946), 1355-1358.
  doi:10.1126/science.1173113
• Hartley, I.P., Hopkins, D.W., Garnett, M.H., Sommerkorn, M. and Wookey, P.A. (2009). No evidence for compensatory thermal adaptation of soil microbial respiration in the study of Bradford et al. (2008). Ecology Letters, 12(7), E12-E14.
  doi:10.1111/j.1461-0248.2009.01300.x
• Wookey, P.A., Aerts, R., Bardgett, R.D., Baptist, F., Bråthen, K.A., Cornelissen, J.H.C., Gough, L., Hartley, I.P., Hopkins, D.W., Lavorel, S. and Shaver, G.R. (2009). Ecosystem feedbacks and cascade processes: understanding their role in the responses of arctic and alpine ecosystems to environmental change. Global Change Biology, 15(5), 1153–1172.
  doi:10.1111/j.1365-2486.2008.01801.x
• Sjögersten, S. and Wookey, P.A. (2009). The impact of climate change on ecosystem carbon dynamics at the Scandinavian mountain birch forest - tundra heath ecotone. Ambio, 38(1), 2-10.
  doi:10.1579/0044-7447-38.1.2
• Garnett, M.H., Hartley, I.P., Hopkins, D.W., Sommerkorn, M. and Wookey, P.A. (2009). A passive sampling method for radiocarbon analysis of soil respiration using molecular sieve. Soil Biology & Biochemistry, 41(7), 1450-1456.
  doi:10.1016/j.soilbio.2009.03.024
• Wookey, P.A. (2008). Experimental approaches to predicting the future of tundra plant communities. Plant Ecology and Diversity, 1(2), 299-307.
  doi:10.1080/17550870802338354
• Hartley, I.P., Hopkins, D.W., Garnett, M.H., Sommerkorn, M. and Wookey, P.A. (2008). Soil microbial respiration in arctic soil does not acclimate to temperature. Ecology Letters, 11(10), 1092-1100.
  doi:10.1111/j.1461-0248.2008.01223.x
• Sjögersten, S., Melander, E. and Wookey, P.A. (2007). Depth distribution of net methanotrophic activity at a mountain birch forest–tundra heath ecotone, northern Sweden. Arctic, Antarctic and Alpine Research, 39(3), 477-480.
  doi:10.1657/1523-0430(06-009)[SJOGERSTEN]2.0.CO;2
• Wookey, P.A. (2007). Climate change and biodiversity in the Arctic—Nordic perspectives. Polar Research, 26(2), 96-103.
  doi:10.1111/j.1751-8369.2007.00035.x
• Walker, M.D., Wahren, C.H., Hollister, R.D., Henry, G.H.R., Ahlquist, L.E., Alatalo, J.M., Bret-Harte, M.S., Calef, M.P., Callaghan, T.V., Carroll, A.B., Epstein, H.E., Jónsdóttir, I.S., Klein, J.A., Magnússon, B., Molau, U., Oberbauer, S.F., Rewa, S.P., Robinson, C.H., Shaver, G.R., Suding, K.N., Thompson, C.C., Tolvanen, A., Totland, Ø., Turner, P.L., Tweedie, C.E., Webber, P.J. and Wookey, P.A. (2006). Plant community responses to experimental warming across the tundra biome. Proceedings of the National Academy of Sciences (PNAS), 103(5), 1342-1346.
  doi:10.1073/pnas.0503198103
• Sjögersten, S. and Wookey, P.A. (2005). The role of soil organic matter quality and physical environment for nitrogen mineralization at the forest-tundra ecotone in Fennoscandia. Arctic, Antarctic, and Alpine Research, 37(1), 118-126.
  doi:10.1657/1523-0430(2005)037[0118:TROSOM]2.0.CO;2
• Sjögersten, S. and Wookey, P.A. (2004). Decomposition of mountain birch leaf litter at the forest-tundra ecotone in the Fennoscandian mountains in relation to climate and soil conditions. Plant and Soil, 262(1-2), 215-227.
  doi:10.1023/B:PLSO.0000037044.63113.fe
• Cooper, E.J. and Wookey, P.A. (2003). Floral Herbivory of Dryas octopetala by Svalbard Reindeer. Arctic, Antarctic, and Alpine Research 35(3), 369-376.
  doi:10.1657/1523-0430(2003)035[0369:FHODOB]2.0.CO;2
• Sjögersten, S., Turner, B.L., Mahieu, N., Condron, L.M. and Wookey, P.A. (2003). Soil organic matter biochemistry and potential susceptibility to climatic change across the forest-tundra ecotone in the Fennoscandian mountains. Global Change Biology, 9(5), 759-772.
  doi:10.1046/j.1365-2486.2003.00598.x
• Sjögersten, S. and Wookey, P.A. (2002). Climatic and resource quality controls on soil respiration across a forest-tundra ecotone in Swedish Lapland. Soil Biology & Biochemistry, 34(11), 1633-1646.
  doi:10.1016/S0038-0717(02)00147-5
• Sjögersten, S. and Wookey, P.A. (2002). Spatio-temporal variability and environmental controls of methane fluxes at the forest-tundra ecotone in the Fennoscandian mountains. Global Change Biology, 8(9), 885-894.
  doi:10.1046/j.1365-2486.2002.00522.x
• Aanes, R., Sæther, B.-E., Smith, F.M., Cooper, E.J., Wookey, P.A. and Øritsland, N.A. (2002). The Arctic Oscillation predicts effects of climate change in two trophic levels in a high-arctic ecosystem. Ecology Letters, 5(3), 445-453.
  doi:10.1046/j.1461-0248.2002.00340.x
• Gough, L., Wookey, P.A. and Shaver, G.R. (2002). Responses of dry heath arctic tundra to long-term nutrient and light manipulation. Arctic, Antarctic, and Alpine Research, 34(2), 211-218.
  doi:10.2307/1552473
• Wookey, P.A., Bol, R.A., Caseldine, C.J. and Harkness, D.D. (2002). Surface age, ecosystem development, and C isotope signatures of respired CO₂ in an alpine environment, north Iceland. Arctic, Antarctic, and Alpine Research, 34(1), 76-87.
  doi:10.2307/1552511
• Pentha, S.M., Tyler, N.J.C., Wookey, P.A. and Mathiesen, S.D. (2001). Experimental warming of reindeer forage plants in situ increases their growth. 11th Nordic Conference on Reindeer Research, Kaamanen, 2001. Rangifer Report, 5, 71 (abstract).
  http://www.rangifer.no/norge/rr05_full.pdf
• Cooper, E.J. and Wookey, P.A. (2001). Field measurements of the growth rates of forage lichens, and the implications of grazing by Svalbard reindeer. Symbiosis, 31, 173-186.
• Cooper, E.J., Smith, F.M. and Wookey, P.A. (2001). Increased rainfall ameliorates the negative effect of trampling on the growth of High Arctic forage lichens. Symbiosis, 31, 153-171.
• Bradford, M.A., Ineson, P., Wookey, P.A. and Lappin-Scott, H.M. (2001). The effects of acid nitrogen and acid sulphur deposition on CH₄ oxidation in a forest soil: a laboratory study. Soil Biology and Biochemistry, 33(12-13), 1695-1702.
  doi:10.1016/S0038-0717(01)00091-8
• Bradford, M.A., Ineson, P., Wookey, P.A. and Lappin-Scott, H.M. (2001). The role of CH₄ oxidation, production and transport in forest soil CH₄ flux. Soil Biology & Biochemistry, 33(12-13), 1625-1631.
  doi:10.1016/S0038-0717(01)00078-5
• Bradford, M.A., Wookey, P.A., Ineson, P. and Lappin-Scott, H.M. (2001). Controlling factors and effects of chronic nitrogen and sulphur deposition on methane oxidation in temperate forest soil. Soil Biology and Biochemistry, 33(1), 93-102.
  doi:10.1016/S0038-0717(00)00118-8
• Bradford, M.A., Ineson, P., Wookey, P.A. and Lappin-Scott, H.M. (2000). Soil CH₄ oxidation: Response to forest clearcutting and thinning. Soil Biology & Biochemistry, 32(7), 1035-1038.
  doi:10.1016/S0038-0717(00)00007-9
• Arft, A.M., Walker, M.D., Gurevitch, J., Alatalo, J.M., Bret-Harte, M.S., Dale, M., Diemer, M., Gugerli, F., Henry, G.H.R., Jones, M.H., Hollister, R.D., Jónsdóttir, I.S., Laine, K., Lévesque, R., Marion, G.M., Molau, U., Mølgaard, P., Nordenhäll, U., Raszhivin, V., Robinson, C.H., Starr, G., Stenström, A., Stenström, M., Totland, Ø., Turner, P.L., Walker, L.J., Webber, P.J., Welker, J.M. and Wookey, P.A. (1999). Responses of tundra plants to experimental warming: Meta-analysis of the International Tundra Experiment. Ecological Monographs, 69(4), 491–511.
  doi:10.1890/0012-9615(1999)069[0491:ROTPTE]2.0.CO;2
• Hodkinson, I.D. and Wookey, P.A. (1999). Functional ecology of soil organisms in tundra ecosystems: towards the future. Applied Soil Ecology, 11(1-2), 111-126.
  doi:10.1016/S0929-1393(98)00142-5
• Robinson, C.H., Wookey, P.A., Lee, J.A., Callaghan, T.V. and Press, M.C. (1998). Plant community responses to simulated environmental change at a high arctic polar semi-desert. Ecology, 79(3), 856-866.
  doi:10.1890/0012-9658(1998)079[0856:PCRTSE]2.0.CO;2
• Welker, J.M., Molau, U., Parsons, A.N., Robinson, C.H. and Wookey, P.A. (1997). Responses of Dryas octopetala to ITEX environmental manipulations: a synthesis with circumpolar comparisons. Global Change Biology, 3(S1), 61-73.
  doi:10.1111/j.1365-2486.1997.gcb143.x
• Wookey, P.A. and Robinson, C.H. (1997). Responsiveness and resilience of high arctic ecosystems to environmental change. Opera Botanica, 132, 215-232.
• Callaghan, T.V., Jonasson, S., Nichols, H., Heywood, R.B. and Wookey, P.A. (1995). Arctic terrestrial ecosystems and environmental change. Philosophical Transactions of the Royal Society of London, Series A, 352(1699), 259-276.
  doi:10.1098/rsta.1995.0069
• Wookey, P.A., Robinson, C.H., Parsons, A.N., Welker, J.M., Press, M.C., Callaghan, T.V. and Lee, J.A. (1995). Environmental constraints on the growth, photosynthesis and reproductive development of Dryas octopetala at a high arctic polar semi-desert, Svalbard. Oecologia, 102(4), 478-489.
  doi:10.1007/BF00341360
• Robinson, C.H., Wookey, P.A., Parsons, A.N., Potter, J.A., Callaghan, T.V., Lee, J.A., Press, M.C. and Welker, J.M. (1995). Responses of plant litter decomposition and nitrogen mineralisation to simulated environmental change at a high arctic polar semi-desert and a sub-arctic dwarf shrub heath. Oikos, 74(3), 503-512.
  doi:10.2307/3545996
• Fisher, P.J., Graf, F., Petrini, L.E., Sutton, B.C. and Wookey, P.A. (1995). Fungal endophytes of Dryas octopetala from a high arctic polar semidesert and from the Swiss Alps. Mycologia, 87(3), 319-323.
  doi:10.2307/3760828
• Parsons, A.N., Press, M.C., Wookey, P.A., Welker, J.M., Robinson, C.H., Callaghan, T.V. and Lee, J.A. (1995). Growth responses of Calamagrostis lapponica to simulated environmental change in the sub-Arctic. Oikos, 72(1), 61-66.
  http://www.jstor.org/stable/3546038
• Wookey, P.A., Welker, J.M., Parsons, A.N., Press, M.C., Callaghan, T.V. and Lee, J.A. (1994). Differential growth, allocation and photosynthetic responses of Polygonum viviparum to simulated environmental change at a high arctic polar semi-desert. Oikos, 70(1), 131-139.
  doi:10.2307/3545708
• Parsons, A.N., Welker, J.M., Wookey, P.A., Press, M.C., Callaghan, T.V. and Lee, J.A. (1994). Growth responses of four sub-Arctic dwarf shrubs to simulated environmental change. Journal of Ecology, 82(2), 307-318.
  doi:10.2307/2261298
• Wookey, P.A., Parsons, A.N., Welker, J.M., Potter, J.A., Callaghan, T.V., Lee, J.A. and Press, M.C. (1993). Comparative responses of phenology and reproductive development to simulated environmental change in sub arctic and high arctic plants. Oikos, 67(3), 490-502.
  doi:10.2307/3545361
• Welker, J.M., Wookey, P.A., Parsons, A.N., Callaghan, T.V., Press, M.C. and Lee, J.A. (1993). Leaf carbon isotope discrimination and vegetative responses of Dryas octopetala to temperature and water manipulations in a High Arctic polar semi-desert, Svalbard. Oecologia 95:463-469.
  doi:10.2307/3545361
• Wookey, P.A., Atkinson, C.J., Mansfield, T.A. and Wilkinson, J.R. (1991). Control of plant water deficits using the “Snow and Tingey system”, and their influence on the water relations and growth of sunflower. Journal of Experimental Botany, 42(5), 589-595.
  doi:10.1093/jxb/42.5.589
• Wookey, P.A., Ineson, P. and Mansfield, T.A. (1991). Effects of atmospheric sulphur dioxide on microbial activity in decomposing Scots pine needle litter and mixed deciduous leaf litter. Agriculture, Ecosystems and Environment, 33(3), 263-280.
  doi:10.1016/0167-8809(91)90006-J
• Wookey, P.A. and Ineson, P. (1991). Combined use of open-air and indoor fumigation systems to study effects of SO₂ on leaching processes in Scots pine litter. Environmental Pollution 74(4), 325-343.
  doi:10.1016/0269-7491(91)90079-C
• Wookey, P.A. and Ineson, P. (1991). Chemical changes in decomposing forest litter in response to atmospheric sulphur dioxide. Journal of Soil Science, 42(4), 615-628.
  doi:10.1111/j.1365-2389.1991.tb00108.x
• Atkinson, C.J., Wookey, P.A. and Mansfield, T.A. (1991). Atmospheric pollution and the sensitivity of stomata on barley leaves to abscisic acid and carbon dioxide. New Phytologist, 117(4), 535- 541.
  doi:10.1111/j.1469-8137.1991.tb00958.x

Contributions to monographs

• Wookey, P.A. (2002). Tundra. In: Mooney, H.A. and Canadell, J. (eds). Encyclopedia of Global Environmental Change, Volume 2: The Earth system - biological and ecological dimensions of global environmental change. Wiley, London. 593-602. ISBN 0-471-97796-9
• Robinson, C.H. and Wookey, P.A. (1997). Microbial ecology, decomposition and nutrient cycling. In: Woodin, S.J. and Marquiss, M. (eds) The Ecology of Arctic Environments. Special Publication Number 13, The British Ecological Society, Blackwell Science, Oxford. 41-68.
• Wookey, P.A. and Robinson, C.H. (1997). Interpreting environmental manipulation experiments in arctic ecosystems: are ‘disturbance’ responses properly accounted for? In: Crawford, R.M.M. (ed). Disturbance and Recovery in Arctic Lands: an Ecological Perspective. 115-134. Kluwer Academic Publishers, Dordrecht, Netherlands.
• Mansfield, T.A., Pearson, M., Atkinson, C.J. and Wookey, P.A. (1993). Ozone, sulphur dioxide and nitrogen oxides: some effects on the water relations of herbaceous plants and trees. In: Jackson, M.B. and CR Black, C.R. (eds). Interacting Stresses on Plants in a Changing Climate. 77-88. Springer-Verlag, Berlin.
• Wolfenden, J., Wookey, P.A., Lucas, P.W. and Mansfield, T.A. (1992). Action of pollutants individually and in combination. In: Barker, J.R. and Tingey, D.T. (eds). Air Pollution Effects on Biodiversity. 72-92. Van Nostrand Reinhold, New York.
• Ineson, P. and Wookey, P.A. (1988). Effects of sulphur dioxide on forest litter decomposition and nutrient release. In: Mathy, P. (ed). Air Pollution and Ecosystems. 254-260. D Reidel Publishers, Dordrecht, Netherlands.

Other publications (not including conference abstracts or contract reports)

• Usher, M. and Wookey, P.A. (2009). Arctic Conservation: An opportunity lost or an opportunity not to be missed? The Circle [published by the WWF International Arctic Programme] 2:6-8.
• Wookey, P.A. and Hartley I (2006). Upland biodiversity, ecosystem processes and services: how strongly coupled are they? The Future of Biodiversity in the Uplands, 8 December, 2006, Battleby Centre, near Perth, Scotland. Conference Proceedings, 5 pp.
  http://www.cms.uhi.ac.uk/conferences/upland_biodiversity_Dec2006/Wookey_extendedabstract.pdf
• Committee on Designing an Arctic Observing Network, National Research Council (2006). Toward an Integrated Arctic Observing Network. ISBN: 0-309-65961-2. 200 pp.
• Sutton, M.A., Chapman, S., Christensen, T., Emmett, B., Erisman, J.W., Fowler, D., Hoosbeek, M.R., Jones, M., Milford, C., Nemitz, E., Pilegaard, K., Riedo, M., Schjoerring, J.K. and Wookey, P.A. (2000). TERICA Working Group 6: Trace gas fluxes and ecosystem functioning. In: Sutton, M.A., Moreno, J.M., van der Putten, W.H. and Struwe, S. (eds). Terrestrial Ecosystem Research in Europe: successes, challenges and policy. 65-74. European Commission, Brussels. ISBN 92-828-9570-X.
• Huntley, B., Baxter, R., Bradshaw, R.H.W., Cramer, W., Dean, A.M., Eronen, M., Evans, S.P., Hofgaard, A., Hulme, P.E., Hytteborn, H., Molau, U., Oksanen, L., Olofsson, J., Sælthun, N.-R., Seppä, H., Sjögersten, S., Thomas, C.J., Venevski, S. and Wookey, P.A. (2000). DART: Dynamic response of the forest-tundra ecotone to environmental change. In: Sutton, M.A., Moreno, J.M., van der Putten, W.H. and Struwe, S. (eds). Terrestrial Ecosystem Research in Europe: successes, challenges and policy. 162-165. European Commission, Brussels ISBN 92-828-9570-X.
• Ekschmitt K, Baxter R, Campbell CD, Ceulemans R, Günther KP, Heal OW, Hector A, Henning F, Kjöller A, Matouch S, Molau U, Nagy PI, Otte A, Pausas JG, Pflug A, Schröter D, Sillence G, Steiner NC, Struwe S, Wolters V and Wookey, PA (2000). TERICA Working Group 1: Ecosystem functioning and management under multiple stresses and extreme events. In: Sutton, M.A., Moreno, J.M., van der Putten, W.H. and Struwe, S. (eds). Terrestrial Ecosystem Research in Europe: successes, challenges and policy. 28-34. European Commission, Brussels. ISBN 92-828-9570-X.
• Baxter R, Evans SP, Emmett B, Harmens H, Huntley B, Kjöller A, Milne R, Mulder J, O’Donnell A, Schulze E-D, Struwe S, Sutton MA Tipping EW and Wookey, PA (2000). TERICA Working Group 5: European carbon budgets / Linking carbon and nitrogen cycles.In: Sutton, M.A., Moreno, J.M., van der Putten, W.H. and Struwe, S. (eds). Terrestrial Ecosystem Research in Europe: successes, challenges and policy. 54-64. European Commission, Brussels. ISBN 92-828-9570-X.
• Wookey, PA (1999). Opening Address. In: Hollister RD (ed) Plant Response to Climate Change: Integration of ITEX Discoveries. Proceedings from the 9th ITEX Meeting January 5-9, 1999. Arctic Ecology Laboratory Report 1, Michigan State University. East Lansing, MI. 9-16.
• Molau U and Wookey, PA (1999). Comparative Experiments and Observations. In: M Turunen, J Hukkinen, OW Heal, NR Sælthun & JI Holten (eds) A Terrestrial Transect for Scandinavia/Northern Europe: Proceedings of the International Scantran Conference. European Commission Ecosystems Research Report No. 31.
• Lawton JH, Moreno JM and Struwe S (eds) with contributions from several others including Wookey, PA (1998). Ecosystems Research and the European Union Environment Policy Needs. Report of the Terrestrial Ecosystems Research Initiative (TERI) Concerted Action Workshop, Toledo, Spain, 28 April to 1 May 1998.
• Heal OW, Broll G, Hooper DU, McConnell J, Webb NR and Wookey, PA (1998). Impacts of global change on tundra soil biology. In: Heal OW, Callaghan TV, Cornelissen JHC, Körner C & Lee SE (eds) Global Change in Europe’s Cold Regions - Ecosystems Research Report 27, pp. 65-134. European Commission, Luxembourg. ISBN 92-828-3346-1.
• Wookey, PA (1997). The ‘intra-tundra’ ecotone (discontinuous vs continuous vegetation cover). Appendix 4 in: Heal OW, Sælthun NR, Holten JI & McConnell J (eds) Ecotones, Biome Dynamics and the Cryosphere: An Outline Plan for the Establishment of an IGBP High Latitude Transect in the Scandinavian / Northern European Region. 43-49. The Research Council of Norway, Oslo.
• Wookey, PA (1997). Review of: F Di Castri and T Younés (eds) (1996) Biodiversity, Science and Development. CAB International, Wallingford. Journal of Ecology, 85:547-548.
• Callaghan TV, Cox NI, Wookey PA & Welker JM (1992). A new NERC Programme of research on ecology in the Arctic. In: Institute of Terrestrial Ecology 1991-1992 Report. 32-33. Natural Environment Research Council.
• Wookey, PA (1990). Review of: JJ MacKenzie and MT El-Ashry (eds) (1989) Air Pollution’s Toll on Forests and Crops. World Resources Institute Series, Yale University Press, New Haven. Journal of Ecology, 78:1154-1155.