Summary and Conclusions

A clearer picture of the manner in which climate change likely will affect agriculture and forestry has taken shape over the past few years. Some important generalizations are now possible. Levels of uncertainty indicated in the text above are not repeated in the list that follows, although we urge the reader to keep these in mind. We state these as major findings from the TAR under the headings of the State-Pressure-Response-Adaptation framework. They include the following:

State

• Constant or declining food prices are expected for at least the next 25 yr, although food security problems will persist in many developing countries as those countries deal with population increases, political crisis, poor resource endowments, and steady environmental degradation. Most economic model projections suggest that low relative food prices will extend beyond the next 25 yr, although our confidence in these projections erodes further out into the 21st century.

• According to United Nations estimates, approximately 23% of all forest and agricultural lands were classified as degraded over the period since World War II.

Pressure

• Although deforestation rates may have decreased since the early 1990s, degradation with a loss of forest productivity and biomass has occurred at large spatial scales as a result of fragmentation, non-sustainable practices and infrastructure development.

• At a worldwide scale, global change pressures (climate change, land-use practices and changes in atmospheric chemistry) are increasingly affecting the supply of goods and services from forests. At present, it appears that the impacts of direct human pressures on forest ecosystems are greater than those directly attributable to climate change, but how the balance of these pressures will develop over the coming century is still to be determined with certainty.

Response

• The most realistic experiments to date - free air experiments in an irrigated environment - indicate that C3 agricultural crops particularly respond favorably to the gradual rise of atmospheric CO2 concentrations over current levels (e.g., wheat yield increases by an average of 28%), although extrapolation of experimental results to real world production where several factors (e.g., nutrients, temperature, precipitation, and others) are likely to be limiting at one time or another remains problematic. Moreover, little is known of crop response to elevated CO2 in the tropics, as most of the research has been conducted in the mid-latitudes.

• Research suggests that for some crops, for example rice, CO2 benefits from a doubling of atmospheric CO2 concentrations over current concentrations may decline quickly as temperatures warm beyond optimum photosynthetic levels. However, crop plant growth may benefit relatively more from CO2 enrichment in drought conditions than in wet conditions.

• The unambiguous separation of the relative influences of elevated ambient CO2 levels, climate change responses, and direct human influences (such as present and historical land-use change) on trees at the global and regional scales is still problematic. In some regions such as the temperate and boreal forests, the legacy of past human activities (land-use change), direct human interventions (including nitrogen-bearing pollution), and climate change impacts, appear to be more significant than CO2 fertilization effects. There appears to be consensus that, whatever its magnitude, any CO2 fertilization effect will saturate (disappear) in the coming century.

• Modeling studies suggest that any warming above current temperatures will diminish crop yields in the tropics while up to 2-3 °C of warming in the mid-latitudes may be tolerated by crops, especially if accompanied by increasing precipitation. The preponderance of developing countries lies in or near the tropics; this finding does not bode well for food production in those countries.

• Where direct human pressures do not mask them, there is increasing evidence of the impacts of climate change on forests associated with changes in natural disturbance regimes, growing season length, and local climatic extremes.

• Recent advances in modeling of vegetation response suggest that transient effects associated with dynamically responding ecosystems to climate change will increasingly dominate over the next century and that during these changes the global forest resource is likely to be adversely affected.

Adaptation

• The ability of livestock producers to adapt their herds to the physiological stress of climate change appears encouraging due to a variety of techniques for dealing with climate stress, but this issue is not well constrained, in part because of the general lack of experimentation and simulations of livestock adaptation to climate change.

• Crop and livestock farmers who have sufficient access to capital and technologies should be able to adapt their farming systems to magnitudes of climate change common in the agricultural literature. Substantial changes in their mix of crops and livestock production may be necessary, however, as considerable costs could be involved in this process because of investments in learning and gaining experience with different crops or irrigation.

• Impacts of climate change on agriculture after adaptation are estimated to result in small percentage changes in overall global income. Nations with large resource endowments (i.e., developed countries) will fare better in adapting to climate change than those with poor resource endowments (i.e., developing countries and countries in transition, especially in the tropics and subtropics) which will fare worse. This, in turn, could worsen income disparities between developed and developing countries.

• Although local forest ecosystems will be highly affected, with potentially significant local economic impacts, it is believed that, at regional and global scales, the global supply of timber and non-wood goods and services will adapt through changes in the global market place. However, there will be regional shifts in market share associated with changes in forest productivity with climate change: in contrast to the findings of the SAR, recent studies suggest that the changes will favor producers in developing countries, possibly at the expense of temperate and boreal suppliers.

• Global agricultural vulnerability to climate change is assessed by the anticipated effects such change will have on food prices. Based on the accumulated evidence of modeling studies, a global temperature rise of greater than 2.5 °C is likely to reverse the trend of falling real food prices. This would greatly stress food security in many developing countries.

Notes

'Easterling and Apps were lead authors on Chapter 5 from which much of the material for this paper was drawn. We acknowledge the co-authors of Chapter 5, including J. Antle, S. Brown, H. Bugmann, L. Erda, R. Fleming, L. Hahn, E. Schulze, O. Sirotenko, B. Sohngen, J. Soussana, G. Takle, J. van Minnen and T. Williamson.

2 Specific information about features of these studies, including climate scenarios used, is reported in Gitay et al., 2001, Table 5.3.

3Continental drying can be expected even when warming is accompanied by increased precipitation due to the effects of higher evapotranspiration.

4 The reader is referred to Gitay et al., 2001, Table 5.3 for details of climate scenarios used in model simulations reported in this section.

References

Adams, R. M., Hurd, B. H., Lenhart, S., and Leary, N.: 1998, 'Effects of global climate change on agriculture: An interpretive review', Clim. Res. 11, 19-30.

Asian Development Bank: 1998, 'The Bank's Policy on Water,' Working Paper, Asian Development Bank, Manila, Philippines.

Alexandratos, N. (ed.): 1995, World Agriculture: Towards 2010. An FAO Study, John Wiley and Sons, Chichester, UK, 488 pp.

Antle, J. M., Capalbo, S. M., and Hewitt, J.: 1999, 'Testing hypotheses in integrated impact assessments: Climate variability and economic adaptation in Great Plains agriculture,' FY 1998/99 Annual Report, National Institute for Global Environmental Change. http://nesen.unl.edu/nigec/facts/projects/Antle98.html

Apps, M. J., Karjalainen, T., Stocks, and B. J., Shaw, C. (eds.): 2002, 'The role of boreal forests and forestry in the global carbon budget. Special Issue', Can. J. Forest. Res. 32, 757914.

Baradas, M. W.: 1999, 'Using PVC pipes to double the irrigated area in the Philippines,' in Proceedings, Philippine Society of Agricultural Engineers' National Convention, General Santas City, Philippines, April, 26-29, 1999.

Bhatti, J. S., Apps, M. J., and Jiang, H.: 2000, 'Advances in Soil Science,' in Lal, R., Kimble, M., Follett, R. F., and Stewart, B. A. (eds.) Assessment of Methods for Soil C Pools, Chapter 35: Examining the Carbon Stocks of Boreal Forest Ecosystems at Stand and Regional Scales, Lewis Publishers. pp. 513-532.

Binkley, C. S., Apps, M. J., Dixon, R. K., Kauppi, P., and Nilsson, L.-O.: 1997, 'Sequestering carbon in natural forests', Critical Reviews in Environmental Science and Technology 27, S23-45.

Bugmann, H. K. M.: 1997, 'Sensitivitiy of forests in the European Alps to future climatic change', Clim. Res. 8, 35-44.

Canadell, J. G., Steffen, W. L., and White, P. S. (eds.): 2002, 'IGBP/GCTE terrestrial transects: Dynamics of terrestrial ecosystems under environmental change(Special Issue)', J. Veg. Sci. 13, 297-448.

Carter, T. R. LaRovere E. L., et al.: 2001, 'Chapter 3: Developing and applying scenarios', in IPCC Working Group II Contribution to the Third Assessment Report on Mitigation of Climate Impacts, Adaptation and Vulnerability, pp 145-190.

Casperson, J. P., Pacala, S. W., Jenkins, J. C., Hurtt, G. C., Moorcraft, P. R., and Birdsey, R. A.: 2000, 'Contributions of land-use history to carbon accumulation in U.S. forests', Science 290, 1148-1151.

Cochrane, M. A., Alencar, A., Schulze, E. D., Souza, C. M., Nepstad, D. C., Lefebvre, P., and Davidson, E. A.: 1999, 'Positive feedbacks in the fire dynamics of closed canopy tropical frests', Science 284, 1832-1835.

Colombo, S. J.: 1998, 'Climatic warming and its effect on bud burst and risk of frost damage to white spruce in Canada', Forestry Chronicle 74, 567-577.

Darwin, R. F., Tsigas, M., Lewandrowski, J., and Raneses, A.: 1995, 'World agriculture and climate change: Economic adaptations', Agricultural Economic Report Number 703, U.S. Department of Agriculture, Economic Research Service, Washington D.C., 86 pp.

Darwin, R.: 1999, 'A farmer's view of the Ricardian approach to measuring agricultural effects of climatic change', Clim. Change 41, 371-411.

Doering, O. C., Habeck, M., Lowenberg-DeBoer, J., Randolph, J. C., Johnston, J. J., Littlefield, B. Z., Mazzocco, M. A., and Pfeifer, R.: 1997, 'Mitigation strategies and unforseen consequences: A systematic assessment of the adaptation of upper midwest agriculture to future climate change', World Resour. Rev. 9, 447-459.

FAO: 1997, State of the world's forests, 1997. United Nations Food and Agriculture Organization, Rome, Italy.

FAO: 2000, Commodity Market Review 1999-2000. Commodities and Trade Division, Food and Agriculture Organization of the United Nations Rome.

Fleming, R. A. and Tatchell, G. M.: 1995, 'Shifts in the flight periods of British aphids: A response to climate warming?' in Harrington, R. and Stork N. E. (eds.) Insects in a Changing Environment, Academic Press, San Diego, CA, U.S.A., pp. 505-508.

Gitay, H., Brown, S., Easterling, W. E., Jallow, B., Antle, J., Apps, M. J., Beamish, R., Chapin, T., Cramer, W., Franji, J., Laine, J., Erda, L., Magnuson, J. J., Noble, I., Price, C., Prowse, T. D., Sirotenko, O., Root, T., Schulze, E.-D., Sohngen, B., and Soussana, J.-F.: 2001. 'Chapter 5: Ecosystems and Their Services,' in IPCC Working Group II Contribution to the Third Assessment Report on Mitigation of Climate Impacts', Adaptation and Vulnerability 235-342.

Hahn, G. L.: 1995, 'Environmental influences on feed intake and performance, health and well-being of livestock'. Japanese J. Livestock Manag. 30, 113-127.

Hahn, G. L. and Mader, T. L.: 1997, Heat waves in relation to thermoregulation, feeding behavior, and mortality of feedlot cattle. Proc., 5th International Livestock Environment Symposium, Minneapolis, MN, 563-571.

Hogg, E. H. and Schwarz, A. G.: 1997, 'Regerenation of planted conifers across climatic moisture gradients on the Canadian prairies: Implications for distribution and climate change', J. Biogeograph. 24, 527-534.

Horie, T., Baker, J. T., Nakagawa, H., and Matsui, T.: 2000, 'Crop ecosystem responses to climatic change: rice', in Reddy, K. R. and H. F. Hodges (eds) Climate Change and Global Crop Productivity,. CAB International, Wallingford, UK, pp. 81-106.

Hulme, M., Barrow, E. M., Arnell, N. W., Harrisson, P. A., Johns, T. C., and Downing, T. E.: 1999, 'Relative impacts of human-induced climate change and natural climate variability,' Nature 397, 688-691.

Houghton, R. A.: 1990, 'Carbon', in Turner, B. L., Clark, R. W. Kates, J. F. Richards, J. T. Matthews, and W. B. Meyer (eds.), The Earth as Transformed by Human Action, Cambridge University Press, pp 393-408.

Johnson, D. G.: 1999, 'Food security and world trade prospects', Am. J. Agric. Econ.80, 941-947.

Joyce, L. A., Mills, J. R., Heath, L. S., McGuire, A. D., Haynes, R. W. and Birdsey, R. A.: 1995, 'Forest sector impacts from changes in forest productivity under climate change', J. Biogeograph.

Kaschishke, E. S., Christensen, N. L., and Stocks, B. J.: 1995, 'Fire, global warming and the carbon balance of boreal forests', Ecol. Appl. 5, 437-451.

Kimball, B. A., Mauney, F. S., Nakayama, F. S., and Idso, S. B.: 1993, 'Effects of elevated CO2 and climate variables on plants', J. Soil Water Conserv. 48, 9-14.

Klinedinst, P. L., Wilhite, D. A., Hahn, G. L., and Hubbard, K. G.: 1993, 'The potential effects of climate change on summer season dairy cattle milk production and reproduction', Clim. Change

Korner, Ch.: 1995, 'Towards a better experimental basis for upscaling plant responses to elevated CO2 and climate warming', Plant Cell and Environ. 18, 1101-1110.

Kurz, W. A. and Apps, M. J.: 1999, 'A 70-year retrospective analysis of carbon fluxes in the Canadian forest sector', Ecol. Appl. 9(2), 526-547.

Kurz, W. A., Apps, M. J., Stocks, B. J., and Volney, W. J. A.: 1995, 'Global Climatic Change: Disturbance Regimes and Biospheric Feedbacks of Temperate and Boreal Forests', in Woodwell G. M. and Mackenzie, F. T. (eds.) Biotic Feedbacks in the Global Climatic System: Will the warming feed the warming? Chapter 6, Oxford University Press. pp. 119-133.

Lewandrowski, J. and Schimmelpfennig, D.: 1999, 'Economic implications of climate change for U.S. agriculture: Assessing recent evidence,' Land Econ. 75, 39-57.

Luo, Y., White, L. W., Canadell, J. G., DeLucia, E. H., Ellsworth, D. S., Finzi, A., Lichter, J., and Schlesinger, W. H.: 2002, 'Sustainability of terrestrial carbon sequestration: A case study in duke forest with inversion approach', Global Biogeochem. Cycles (in press).

Matthews, R. B., Kropff, M. J., and Bachelet, D.: 1997, 'Simulating the impact of climate change on rice production in Asia and evaluating options for adaptation', Agric. Syst. 54, 399-425.

Mauney, J. R., Kimball, B. A., Pinter, P. J., Lamortne, R. L., Lewin, K. F., Nagy, J., and Hendrey,

G. R.: 1994, 'Growth and yield of cotton in response to a free-air carbon dioxide enrichment enrichment (FACE) environment', Agric. ForestMeteorol. 70, 49-67.

McGuire, A. D., Wirth, C., Apps, M., Beringer, J., Clein, J., Epstein, H., Kicklighter, D. W., Bhatti, J., Chapin III, F. S., de Groot, B., Efremov, D., Eugster, W., Fukuda, W., Gower, T., Hinzman, L., Huntley, B., Jia, G. J., Kasischke, E., Melillo, J., Romanovsky, V., Shvidenko, A., Vaganov, E., and Walker, D.: 2001, 'Environmental variation, vegetation distribution, carbon dynamics, and water/energy exchange in high latitudes,' J. Veg. Sci. 13, 301-314.

McCarthy et al. (eds.): 'Climate Change 2001-Impacts, Adaptations and Mitigation of Climate Change: Scientific-Technical Analyses' Contribution of Working Group II to the Third Assessment Report of the Intergovernmental Panel on Climate Change, United Nations Environment Programme, World Meteorological Organization, Cambridge University Press.

Mearns, L. O., Giorgi, F., McDaniel, L., and Shields, C.: 1995, 'Analysis of climate variability and diurnal temperature in a nested regional climate model: Comparison with observations and doubled CO2 results', Clim. Dyn. 11, 193-209.

Myneni, R. B., Keeling, C. D., Tucker, C. J., Asrar, G., and Nemani, R. R.: 1997, 'Increased plant growth in the northern high latitudes from 1981-1991', Nature 386, 698-702.

Nepstad, D. C., Verissimo, A., Alancar, A., Nobre, C., Lima, E., Lefebve, P. A., Schlesinger, P., Potter, C., Moutinho, P., Mendoza, E., Cochrane, M., and Brooke, V.: 1999, 'Large-scale impoverishment of Amazonian forests by logging and fire', Nature 348, 505-508.

Neilson, R. P., Prentice, I. C., Smith, B., Kittle, T., and Viner, D.: 1998, 'Simulated changes in vegetation distribution under global warming,' in: Watson, R. T., Zinyowera M. C., and Moss, R.

H.(eds) The Regional Impacts of Climate Change: AnAsessment ofVuilnerability, Special Report of IPCC Working Group II, Cambridge University Press, Cambridge, UK and New York, NY, ISA, pp. 441-446.

Norby, R. J., Wullschleger, S. D., Gunderson, C. A., Johnson, D. W., and Ceulemans, R.: 1999, 'Tree response to rising CO2 in field experiments: Implications for the future forest', Plant Cell Environ. 22, 683-714.

Ogren, E., Nilsson, T., and Sunblad, L. G.: 1997, 'Relationship between respiratory depletion of sugars and loss of cold hardiness in coniferous seedlings over-wintering at raiser temperatures: Indications of different sensitivities of spruce and pine', Plant Cell Environ. 20(2), 247-253.

Oldeman, R. L., Hakkeling, T. A., and Sombroek, W. G.: 1991, World Map of the Status of Human-Induced Soil Degradation, 2nd edn. International Soil Reference and Information Centree, Wageningen, Netherlands.

Overpeck, J. T., Rind, D., and Goldberg, R.: 1990, 'Climate-induced changes in forest disturbance and vegetation,' Nature 343, 51-53.

Parry, M., Fischer, C., Livermore, M., Rosenzweig, C., and Iglesias, A.: 1999, 'Climate change and world food security: A new assessment', Global Environ. Change 9, S51-S67.

Paustian, K., Elliott, E. T., and Hahn, L.: 1999, Agroecosystem Boundaries and C Dynamics with Global Change in the Central United States, FY 1998/1999 Progress Report, National Institute for Global Environmental Change. http://nigec.ucdavis.edu.

Pingali, P.: 1994, 'Technological prospects for reversing the declining trend in Asia's rice productivity', in Anderson, J. R. (ed.) Agricultural Technology: Policy Issues for the International Community, Wallingford, UK: CAB International in association with the World Bank, pp. 384401.

Pittock, A. B.: 1999, 'Climate change: Question of significance,' Nature 397, 657-658.

Pinstrup-Andersen, P. and Pandya-Lorch, R.: 1998. 'Food security and sustainable use of natural resources: A 2020 vision', Ecol. Economics 26, 1-10.

Pinter, P. J. Jr., Kimball, B. A., Garcia, R. L., Wall, G. W., Hunsaker, D. J., and LaMorte, R. L.: 1996, 'Free-air CO2 enrichment: Responses of cotton and wheat crops,' in Koch, G. W. and Mooney H. A. (eds.) Carbon Dioxide and Terrestrial Ecosystems, Academic Press, San Diego, CA, U.S.A., pp. 215-249.

Prentice, et al.: 2001, Chapter X in IPCC TAR WG1 report.

Prentice, I. C., Farquhar, G. D., Fasham, M. J. R., Goulden, M. L., Heimann, M., Jaramillo, V. J., Kheshgi, H. S., Le Quere, C., Scholes, R. J., and Wallace, D. W. R.: 2001, Chapter VI: The Carbon Cycle and Atmospheric Carbon Dioxide, in IPCC Working Group I Contribution to the Third Assessment Report on The Scientific Basis, Houghton, J. T. et al. (eds.), Cambridge University Press, UK, pp. 183-237.

Price, D. T., Halliwell, D. H., Apps, M. J. and Peng, C. H.: 1999a, 'Adapting a patch model to simulate the sensitivity of Central-Canadian boreal ecosystems to climate variability', Journal of Biogeography 26, 1101-1113.

Price, D. T., Peng, C. H., Apps, M. J., and Halliwell, D. H.: 1999b, 'Simulating effects of climate change on boreal ecosystem and carbon pools in central Canada', J. Biogeograph. 26, 12371248.

Reilly, J., et al.: 1996, 'Agriculture in a changing climate: Impacts and adaptations', in Houghton, J. T., Meiro Filho, L. G., Callander, B. A., Harris, N., Kattenberg, A., and Maskell, K. (eds.).Climate Change 1995: The Science of Climate Change. Contribution of Working Group I to theSecond Assessment of the Intergovermental Panel on Climate Change Cambridge University Press, Cambridge, pp. 584.

Repo, T., Hanninen, H., and Kellomaki, S.: 1996, 'The effects of long-term elevation of air temperatures and CO2 on the forest hardiness of Scots Pine', Plant Cell Environ. 19(2), 209-216.

Robinson, D. C. E., Kurz, W. A., and Pinkham, C.: 1999, Estimating the carbon losses for deforestation in Canada. ESSA Technologies Lt., National Climate Change Secretariat, Ottawa, ON, Canada, available at http://www.nccp.ca/html/index.htm

Rosegrant, M. W., Agcaoili-Sombilla, M., and Perez, N. D.: 1995, Global Food Projections to 2020: Implications for Investment, 2020 Vision for Food, Agriculture, and the Environment. Discussion Paper no. 5, International Food Policy Research Institute, Washington, D.C.

Rosegrant, M. W. and Ringler, C.: 1997, 'World food markets into the 21st century: Environmental and resource constraints and policies', Australian J. Agric.Resour. Econ. 41, 401-428.

Rosenzweig, C. and Iglesias, A.: 1998, 'The use of crop models for international climate change impact assessment', in Tsuji, G. Y., Hoogrnboom, G., and Thorton, P. K. (eds.) Understanding Options for Agriculture production Kulwer Academic Publishers, pp. 267-292.

Rosenzweig, C., Iglesias, A., Yang, X., Epstein, P., and Chivian, E.: 2000, Climate Change and U. S. Agriculture: The Impacts of Warming and Extreme Weather Events on Productivity, Plant Diseases, and Pests, Center for Health and the Global Environment, Harvard Medical School, Boston, 46 pp.

Samarakoon, A. B. and Gifford, R. M.: 1995, 'Soil water content under plants at high CO2 concentration and interactions with the direct CO2 effects: A Species comparison', J. Biogeograph. 22, 193-202.

Shaver, G. R., Canadell, J., Chapin III, F. S., Gurevitch, J., Harte, J., Henry, G., Ineson, P., Jonasson, S., Melillo, J., Pitelka, L., and Rustad, L.: 2000, 'Global warming and terrestrial ecosystems: A conceptual framework for analysis', Bio. Sci. 50, 871-882.

Schiff, M. and Valdez, A.: 1996, 'Agricultural incentives and growth in developing countries: A crosscountry perspective', in Antle, J. M. and Sumner, D. A. (eds.) The Economics of Agriculture, Vol. 2: Papers in Honor ofD. Gale Johnson Chicago, University of Chicago Press, pp. 386-399.

Schimel, D. S., House, J. I., Hibbard, K. A., Bousquet, P., Ciais, P., Peylin, P., Braswell, B. H., Apps, M. J., Baker, D., Bondeau, A., Canadell, J., Churkina, G., Cramer, W., Denning, A. S., Field, C. B., Friedlingstein, P., Goodale, C., Heimann, M., Houghton, R. A., Melillo, J. M., Moore III, B., Murdiyarso, D., Noble, I., Pacala, S. W., Prentice, I. C., Raupach, M. R., Rayner, P. J., Scholes, R. J., Steffen, W. L., and Wirth, C.: 2001, 'Recent patterns and mechanisms of carbon exchange by terrestrial ecosystems', Nature 414, 169-172.

Schneider, S. H., Easterling, W. E., and Mearns, L. O.: 2000, 'Adaptation: Sensitivity to natural variability, agent assumptions and dynamic climate changes', Clim. Change 45, 203-221.

Schvidenko, A.: 2000, 'Golbal significance of disturbances in boreal forests', in Connard, S. G. (ed). Disturbances in Boreal Forest Ecosystems: Human Impacts and Natural Resources, USDA-Forest Service North Central Research Station. St. Paul, U.S.A., General Technical Report NC-209, 17-29.

Sedjo, R. A.: 1999, 'The potential of high-yield plantation forestry for meeting timber needs', New Forests 17(1-3), 339-359.

Semenov M. A. and Porter J. R.: 1995, 'Climatic variability and the modelling of crop yields', Agricultural and Forest Meterology 73, 265-283.

Semenov, M. A., Wolf, J., Evans, L. G., Eckersten, H. and Eglesias, A.: 1996, 'Comparison of wheat simulation models under climate change. II. Application of climate change scenarios', Climate Research 7, 271-281.

Sellers, P. J., et al.: 1997, 'BOREAS in 1997: Experiment overview, scientific resuotsa nd future directions', J. Geophys. Res. 103(D24), 731-728, 769.

Sohngen, B. and Mendelsohn, R.: 1998, 'Valuing the market impact of large scale ecological change: The effect of climate change on U.S. timber', Am. Econ. Rev. 88(4), 689-710.

Sohngen, B., Mendelsohn, R., and Sedjo, R.: 2000, Measuring climate change impacts with a global timber model, Working Paper, Department of Agricultural, Environmental and Development Economics, Ohio State University, Columbus Ohio, U.S.A..

Solomon, A. M., Ravindranath, N. H., Stewart, R. B., Weber, M., Nilsson, S., Duinker, P. N., Fearn-side, P. M., Hall, P. J., Ismail, R., Joyce, L. A., Kojima, S., Makundi, W. R., Pollard, D. F. W., Shvidenko, A., Skinner, W., Stocks, B. J., Sukumar, R., and Deying, X.: 1996, 'Wood production under changing climate and land use,' in Watson, R. T., Zinyowera, M. C., and Moss, R. H.(eds.) Climate Change 1995: Impacts, Adaptions, and Mitigation of Climate Change: Scientific-Technical Analyses. Contribution of Working Group II to the Second Assessment Report for the Intergovernmental Panel on Climate Change, Cambridge University Press, Cambridge, United Kingdom and New York, NY, U.S.A., 487-510.

Solomon, A. M. and Leemans, R.: 1997, 'Boreal forest carbon stocks and wood supply: Past, present and future responses to changing climate, agriculture and species availability', Agric. Forest Meteorol. 84, 137-151.

Strzepek, K. M., Major, C. D., Rosenzweig, C., Iglesias, A., Yates, D., Holt, A., and Hillel, D.: 1999, 'New methods of modeling water availability for agriculture under climate change: The U. S. corn belt', J. Am. Water Resour. Assoc. 35(6), 1639-1655.

Tian, H., J. Melillo, Kicklighter, D. W., McGuire, D. A., Helfrich, J. V. K., Moore III, B., and Vorosomarty, C. J.: 1998, 'Effect of interannual climate variability on carbon storage in Amazonian ecosystems', Nature 396, 664-667.

Tweeten, L.: 1998, 'Dodging a Malthusian Bullet in the 21st Century,' Agribusiness 14, 15-32.

VEMAP Members: 1995, 'Vegetation/ecosystem modeling and analysis project: Comparing biogeography and biogeochemistry models in a continental scale study of terrestrial ecosystem responses to climate change and CO2 doubling', Global Biogeochem. Cycles 9, 407-437.

Watson R. T., Noble, I. R., Bolin, B., Ravindranath, N. H., Verardo, D. J., and Dokken, D. J. (eds): 2000, Land Use, Land-Use Change and Forestry. Special Report of the IPCC, Cambridge University Press, Cambridge, U.S., 377 pp.

Watson R. T., Zinyowera, M. C., Moss, R. H., and Dokken, D. J. (eds): 1998, 'The Regional Impacts of Climate Change: An Asessment of Vulnerability,' A Special Report of the IPCC Working Group II, Cambridge University Press, Cambridge, U.S., 517 pp.

Williams D. W. and Liebhold, A. M.: 1997, 'Latitudinal shifts in spruce budworm (Lepidoptera Tor-ticidae) outbreaks and sprice-fir forest distributions with climate change', Acta Phytopathologica et Entomologica Hungarica 32, 2G5-215.

Winnett, S. M.: 1998, 'Potential effects of climate change on U.S. forests: A review', Clim. Res. 11, 39-49.

Winters, P., Murgai, R., de Janvry, A., Sadoulet, E., and Frisvold, G.: 1999, 'Climate change and agriculture: Effects on developing countries,' in Frisvold G. and Kuhn, B. (eds.) Global Environmental Change and Agriculture, Edward Elgar Publishers, Cheltenham, England.

World Bank: 1993, Water Resources Management, A World Bank Policy Study, Washington, D. C., U.S.A., 14G pp.

Yu, Z., Apps, M. J., and Bhatti, J. S.: 2GG2, 'Implications of floristic and environmental variation for carbon cycle dynamics in boreal forest ecosystems along a transect in central Canada,' J. Veg. Sci. 13, 328-341.

(Received 15 December 2GG3; in revised form 22 April 2GG4)

0 0

Post a comment