Global Change Sites Publications

CO₂ Enrichment Experiments Publications

Australian Savanna Free Air CO₂ Enrichment Facility (OzFACE)

Stokes CJ, Ash AJ, Tibbett M & Holtum JAM (2005) OzFACE: the Australian Savanna Free Air CO₂ Enrichment facility and its relevance to carbon cycling issues in a tropical savanna. Australian Journal of Botany. 53: 677-687.

Basel

Asshoff, R., Zotz, G., and Körner, Ch. 2006. Growth and phenology of mature temperate forest trees in elevated CO₂. Global Change Biology 12:848-861.

Cech, P.G., Pepin, S., and Körner, Ch. 2003. Elevated CO₂ reduces sap flux in mature deciduous forest trees. Oecologia 137:258-268.

Keel, S.G., Siegwolf, R.T.W., and Körner, C. 2006. Canopy CO₂ enrichment permits tracing the fate of recently assimilated carbon in a mature deciduous forest. New Phytologist 172:319-329.

Körner, Ch., Asshoff, R., Bignucolo, O., Hättenschwiler, S., Keel, S.G., Pelaez-Riedl, S., Pepin S, Siegwolf, R.T.W., and Zotz, G. 2005. Carbon flux and growth in mature deciduous forest trees exposed to elevated CO₂. Science 309:1360-1362.

Pepin, S. and Körner, Ch. 2002. Web-FACE: a new canopy free-air CO₂ enrichment system for tall trees in mature forests. Oecologia 133:1-9.

Steinmann, K., Siegwolf, R., Saurer, M., and Korner, C. 2004. Carbon fluxes to the soil in a mature temperate forest assessed by C-13 isotope tracing. Oecologia 141:489-501.

Zotz, G., Pepin, S., and Körner, Ch. 2005. No down-regulation of leaf photosynthesis in mature forest trees after three years of exposure to elevated CO₂. Plant Biology 7:369-374.

Braunschweig

Blagodatsky, S.A., Blagodatsky, E.V., Anderson, T.H., and Weigel, H.J. 2006. Kinetics of the respiratory response of the soil and rhizosphere microbial communities in a field experiment with an elevated concentration of atmospheric CO₂. Eurasian Soil Science 39:290–297.

Burkart, S., Manderscheid, R. and Weigel, H.J. 2002. Interactive effects of atmospheric CO₂-concentration and plant available soil water content and canopy evapotranspiration and conductance of spring wheat. In: Villalobos, F.J. and Testi, L. (eds) 7th ESA Congress : Cordoba, Spain, 15-18 July 2002 ; book of proceedings. Sevilla, Espana : Consejeria di Agricultura y Pesca. p. 67-68.

Giesemann, A. 2005. Changes in soil C isotopic composition in an agroecosystem under Free Air Carbon Dioxide Enrichment (FACE) treatment during a crop rotation period. Rapid Communications in Mass Spectrometry 19:1373-1380.

Manderscheid, R., Fruhauf, C. and Weigel, H.J. 2002. Effects of free-air CO₂ enrichment (FACE) and soil nitrogen fertilizer on radiation absorption, radiation use efficiency and yield of winter barley. In: Villalobos, F.J. and Testi, L (eds) Book of proceedings / 7th ESA Congress, 15-18 July, 2002. Cordoba, Spain. Sevilla, Espana : Consejeria di Agricultura y Pesca,. p. 207-208.

Soe, A., Giesemann, A., Anderson, T.H., Weigel, H.J. and Buchmann, N. 2004. Influence of elevated CO₂ on soil respiration and its partitioning into recently assimilated and older carbon sources. Plant and Soil 262: 85-94.

Sticht, C., Schrader, S., Giesemann, A., and Weigel, H.J. 2006. Effects of elevated CO₂ and N fertilization on abundance, diversity and C isotopic signature of collembolan communities in arable soil. Applied Soil Ecology 34:219-229.

Weigel, H.J. und Dammgen, U. 2003. Das Braunschweiger Kohlenstoff-Projekt: Atmosphaerisches Fluss-Monitoring und Free Air Carbon Dioxide Enrichment (FACE). In: Esser, G.; Holm-Mueller, K; Prentice, C. (Hrsg.), Bedeutung der Wechselwirkungen Biosphäre-Atmosphäre für die nachhaltige Nutzung der Biosphäre und den Klimaschutz, Bonn. p. 55-63Weigel, H.J. and Manderscheid, R. 2004. CO₂ enrichment effects on forage and grain nitrogen concentration of pasture and cereal plant species. Journal of Crop production 13:73-89.

Weigel, H.J. and Dammgen, U. 2000. The Braunschweig Carbon Project: atmospheric flux monitoring and Free Air Carbon Dioxide Enrichment (FACE). Journal of Applied Botany 74:55-60.

Weigel, H.J., Fruhauf, C., Burkart, S. and Dammgen, U. 2002. The Braunschweig Carbon Project: Free Air Carbon Dioxide Enrichment (FACE) and atmospheric flux monitoring in arable crop rotation systems. In: Villalobos FJ, Testi L (eds) Book of proceedings / 7th ESA Congress, 15-18 July, 2002. Cordoba, Spain. Sevilla, Espana : Consejeria di Agricultura y Pesca. p. 791-792.

Weigel, H.J., Manderscheid, R., Burkart, S., Pacholski, A., Waloszcyk, K., Fruhauf, C., and Heinemeyer, O. 2006. Responses of an arable crop rotation system to elevated CO₂. In: Nösberger, J., Long, S.P., Norby, R.J., Stitt, M., Hendrey, G.R., and Blum, H. (eds.), Managed Ecosystems and CO₂ - Case Studies, Processes, and Perspectives. Series: Ecological Studies 187, Springer Verlag. p. 121-137.

Weigel, H.J., Pacholski, A., Burkart, S., Helal, M., Heinemeyer, O., Kleikamp, B., Manderscheid, R., Fruhauf, C., Hendrey, G.R., Lewin, and Nagy, J. 2005. Carbon turnover in a crop rotation under Free Air CO₂ Enrichment (FACE). Pedosphere 15: 728-738.

Linden

Jäger, H.-J., Schmidt, S.W., Kammann, C., Grünhage, L., Müller, C., and Hanewald, K. 2003. The University of Giessen free-air carbon dioxide enrichment study: description of the experimental site and of a new enrichment system. Journal of Applied Botany 77:117-127.

Kammann, C., Grünhage, L., Grüters, U., Janze, S., and Jäger, H.-J. 2005. Response of aboveground grassland biomass and soil moisture to moderate long-term CO₂ enrichment. Basic and Applied Ecology 6:351-365.

Stillberg – Davos

Handa, I.T., Körner, Ch., and Hättenschwiler, S. 2005. A test of the tree-line carbon limitation hypothesis by in situ CO₂ enrichment and defoliation. Ecology 86:1288-1300.

Handa, I.T., Körner, C., and Hättenschwiler, S. 2006. Conifer stem growth at the altitudinal treeline in response to four years of CO₂ enrichment. Global Change Biology 12:2417-2430.

Hättenschwiler, S., Handa, I.T., Egli, L., Asshoff, R., Ammann, W., and Körner, C. 2002. Atmospheric CO₂ enrichment of alpine treeline conifers. New Phytologist 156:363-375.

CO₂ and Nitrogen Manipulation Publications

Duke Forest FACE Experiment: Forest-Atmosphere Carbon Transfer and Storage (FACTS-I)

Albani, M., Medvigy, D., Hurtt, G.C., and Moorcroft, P. 2006. The contributions of land-use change, CO₂ fertilization, and climate variability to the Eastern US carbon sink. Global Change Biology 12:2370-2390

Bernhardt, E., Barber, J., Pippen, J., Taneva, L., Andrews, J., and Schlesinger, W. 2006. Long-term effects of free air CO₂ enrichment (FACE) on soil respiration. Biogeochemistry 77(1):91-116.

Billings, S. and Ziegler, S. 2005. Linking microbial activity and soil organic matter transformations in forest soils under elevated CO₂. Global Change Biology 11:203-212.

Ceulemans, R., De Angelis, P., Finzi, A., Karnosky, D., Kubiske, M., Lukac, M., Pregitzer, K., Scarascia-Mugnozza, G., Schlesinger, W., and Oren, R. 2005. Forest response to elevated CO₂ is conserved across a broad range of productivity. In: Proceedings of the National Academy of Sciences 102:18052-18056.

Crous, K. and Ellsworth, D. 2004. Canopy position affects photosynthetic adjustments to long-term elevated CO₂ concentration (FACE) in aging needles in a mature Pinus taeda forest. Tree Physiology 24:961-970.

Davey, P., Hunt, S., Hymus, G., DeLucia, E., Drake, B., Karnosky, D., and Long, S. 2004. Respiratory oxygen uptake is not decreased by an instantaneous elevation of [CO₂], but is increased by long-term growth in the field at elevated [CO₂]. Plant Physiology 134:520-527.

DeLucia, E.H., Moore, D.J., Hamilton, J.G., Thomas, R.B., Springer, C.J., and Corby, R.J. 2005. The Changing Role of Forests in the Global Carbon Cycle: Responding to Elevated Carbon Dioxide in the Atmosphere. In: Lal, R., Duxbury, J., Stewart, B.A., and Hansen, D.O. (eds.) Climate Change and Global Food Security. CRC Press, Marcel Dekker.

DeLucia, E., Moore, D., and Norby, R. 2005. Contrasting responses of forest ecosystems to rising atmospheric CO₂: Implications for the global C cycle. Global Biogeochemical Cycles 19(3): GB3006, doi:10.1029/2004GB002346.

Ellsworth, D., Reich, P., Naumburg, E., Koch, G., Kubiske, M., and Smith, S. 2004. Photosynthesis, carboxylation and leaf nitrogen responses of 16 species to elevated p CO₂ across four Free-Air CO₂ Enrichment experiments in forest, grassland and desert. Global Change Biology 10:2121-2138.

Finzi, A., DeLucia, E., and Schlesinger, W. 2004. Canopy N and P dynamics of a southeastern US pine forest under elevated CO₂. Biogeochemistry 69:363–378.

Finzi, A.C., Moore, D.J., DeLucia, E.H., Kim, H-S., Jackson, R.L., Lichter, J., McCarthy, H., Oren, R., Pippen, J.S., and Schlesinger, W.H. 2006. Progressive nitrogen limitation of ecosystem processes under elevated CO₂ in a warm-temperate forest. Ecology 87(1):15-25.

Finzi, A.C., Sinsabaugh, R.L., Long, T.M., and Osgood, M.P. 2006. Microbial community responses to atmospheric carbon dioxide enrichment in a warm-temperate forest. Ecosystems 9:215-226.

Gonzalez-Meler, M.A. and Taneva, L. 2005. Integrated effects of atmospheric CO₂ concentration on plant and ecosystem respiration. In: Lambers, H. and Ribas-Carbo, M. (eds.). Plant Respiration. Kluwer-Academic Publishers, Dordrecht. p. 211-259.

Gonzalez-Meler, M.A., Taneva, L., and Trueman, R.J. 2004. Plant Respiration and Elevated Atmospheric CO₂ Concentration: Cellular Responses and Global Significance Annals of Botany 94:647-656.

Hamilton, J., Zangerl, A., Berenbaum, M., Pippen, J., Aldea, M., and DeLucia, E. 2004. Insect herbivory in an intact forest understory under experimental CO₂ enrichment. Oecologia 138:566-573.

Herrick, J., Maherali, H., and Thomas, R. 2004. Reduced stomatal conductance in sweetgum(Liquidambar styraciflua) sustained over long-term CO₂ enrichment. New Phytologist 162:387-396.

Hofmockel, K.S. and Schlesinger, W.H. 2007. Carbon dioxide effects on heterotrophic dinitrogen fixation in a temperate pine forest. Soil Science Society of America Journal 71(1):140-144.

Hyvönen, R., Ågren, G.I., Linder, S., Persson, T., Cotrufo, M.F., Ekblad, A., Freeman, M., Grelle, A., Janssens, I.A., Jarvis, P.G., Kellomäki, S., Lindroth, A., Loustau, D., Lundmark, T., Norby, R.J., Oren, R., Pilegaard, K., Ryan, M.G., Sigurdsson, B.D., Strömgren, M., van Oijen, M., and Wallin. G. 2007. The likely impact of elevated [CO₂], nitrogen deposition, increased temperature and management on carbon sequestration in temperate and boreal forest ecosystems: a literature review. New Phytologist 173:463-480.

Johnson, D.W. 2006. Progressive N limitation in forests: review and implications for long-term responses to elevated CO₂. Ecology 87(1):64-75.

King, J., Hanson, P., Bernhardt, E., DeAngelis, P., Norby, R., and Pregitzer, K. 2004. A multiyear synthesis of soil respiration responses to elevated atmospheric CO₂ from four forest FACE experiments Global Change Biology 10:1027-1042.

Knepp, R., Hamilton, J., Mohan, J., Zangerl, A., Berenbaum, M., and DeLucia, E. 2005. Elevated CO₂ reduces leaf damage by insect herbivores in a forest community. New Phytologist 167:207-218.

LaDeau, S.L. and Clark, J.S. 2006. Elevated CO₂ and tree fecundity: the role of tree size, interannual variability and population heterogeneity. Global Change Biology 12(5):822-833.

LaDeau, S.L. and Clark, J.S. 2006. Pollen production in Pinus taeda growing in elevated CO₂. Functional Ecology 20:541-547.

Lichter, J., Barron, S., Finzi, A., Irving, K., Roberts, M., Stemmler, E., and Schlesinger, W. 2005. Soil carbon sequestration and turnover in a pine forest after six years of atmospheric CO₂ enrichment. Ecology 86(7):1835-1847.

Luo, Y., Hui, D., and Zhang, D. 2006. Elevated CO₂ stimulates net accumulations of carbon and nitrogen in land ecosystems: a meta-analysis. Ecology 87(1):53-63.

Luo, Y., Su, B., Currie, W., Dukes, J., Finzi, A., Hartwig, U., Hungate, B., McMurtrie, R., Oren, R., Parton, W., Pataki, D., Shaw, M., Zak, D., and Field, C. 2004. Progressive nitrogen limitation of ecosystem responses to rising atmospheric carbon dioxide. BioScience 54(8):731-739.

McCarthy, H.R., Oren, R., Finzi, A.C., and Johnsen, K.H. 2006. Canopy leaf area constrains [CO₂]-induced enhancement of productivity and partitioning among aboveground carbon pools. In: Proceedings of the National Academy of Sciences of the USA. 103:19356-19361.

McCarthy, H.R., Oren, R., Kim, H-S., Johnsen, K.H., Maier, C., Pritchard, S.G., and Davis, M.A. 2006. Interaction of ice storms and management practices on current carbon sequestration in forests with potential mitigation under future CO₂ atmosphere. Journal of Geophysical Research 111: D15103, doi:10.1029/2005JD006428.

McElrone, A.J., Reid, C.D., Hoye, K.A., Hart, E., and Jackson, R.B. 2005. Elevated CO₂ reduces disease incidence and severity of a red maple fungal pathogen via changes in host physiology and leaf chemistry. Global Change Biology 11:1828-1836.

Mohan, J., Clark, J., and Schlesinger, W. 2004. Genetic variation in germination, growth, and survivorship of red maple in response to subambient through elevated atmospheric CO₂. Global Change Biology 10:233-247.

Mohan, J.E., Ziska, L.H., Thomas, R.B., Sicher, R.C., George, K., Clark, J.S., and Schlesinger, W.H. 2006. Biomass and toxicity responses of poison ivy (Toxicodendron radicans) to elevated atmospheric CO₂. In: Proceedings of the National Academy of Sciences of the USA. 103(24):9086-9089.

Neher, D.A., Weicht, T.R., Moorhead, D.L., and Sinsabaugh,. R.L. 2004. Elevated CO₂ alters functional attributes of nematode communities in forest soils. Functional Ecology 18:584-591.

Norby, R., DeLucia, E., Gielen, B., Calfapietra, C., Giardina, C., King, J., Ledford, J., McCarthy, H., Moore, D., Nowak, R.S., Ellsworth, D.S., and Smith, S.D. 2004. Functional responses of plants to elevated atmospheric CO₂ - Do photosynthetic and productivity data from FACE experiments support early predictions? Tansley Review. New Phytologist 162:253-280.

Palmroth, S., Oren, R., McCarthy, H.R., Johnsen, K.H., Finzi, A.C., Butnor, J.R., and Ryan, M.G. 2006. Aboveground sink strength in forests controls the allocation of carbon below ground and its [CO₂]-induced enhancement. In: Proceedings of the National Academy of Sciences of the USA. 103:19362-19367.

Parrent, J.L., Morris, W.F., and Vilgalys, R. 2006. CO₂-enrichment and nutrient availability alter ectomycorrhizal fungal communities. Ecology 87(9):2278-2287.

Schlesinger, W.H., Bernhardt, E.S., DeLucia, E.H., Ellsworth, D.H., Finzi, A.C., Hendrey, G.R., Hofmockel, K.S., Lichter, J., Matamala, R., Moore, D., Oren, R., Pippen, J.S., and Thomas, R.B. 2006. The Duke Forest FACE experiment: CO₂ enrichment of a loblolly pine forest. In: Osberger, J., Long, S.P., Norby, R.J., Stitt, M., Hendrey, G.R., and Blum H (eds.) Managed Ecosystems and CO₂ Case Studies, Processes, and Perspectives. Ecological Studies 187:197-212.

Springer, C., DeLucia, E., and Thomas, R. 2005. Relationships between net photosynthesis and foliar nitrogen concentrations in a loblolly pine forest ecosystem grown in elevated atmospheric carbon dioxide. Tree Physiology 25(4):385-394.

Springer, C.J. and Thomas, R.B. 2007. Photosynthetic responses of forest understory tree species to long-term exposure to elevated carbon dioxide concentration at the Duke Forest FACE experiment. Tree Physiology 27(1):25-32.

Suwa, M., Katul, G., Oren, R., Andrews, J., Pippen, J., Mace, A., and Schlesinger, W. 2004. Impact of Elevated Atmospheric CO₂ on Forest Floor Respiration in a Temperate Pine Forest. Global Biogeochemical Cycles 18(2): GB2013, doi:10.1029/2003GB002182.

Taneva, L., Pippen, J.S., Schlesinger, W.H., and Gonzalez-Meler, M.A. 2006. The turnover of carbon pools contributing to soil CO₂ and soil respiration in a temperate forest exposed to elevated CO₂ concentration. Global Change Biology 12:983-994.

Nitrogen Addition Site Information

Aber Forest, Wales, UK (NITREX)

Emmett, B.A., Brittain, S.A., Hughes, S., Gorres, J., Kennedy, V., Norris, D., Rafarel, R., Reynolds, B., and Stevens, P.A. 1995. Nitrogen additions (NaNO₃ and NH₄NO₃) at Aber forest, Wales: I. Response of throughfall and soil water chemistry. Forest Ecology and Management 71:45-59.

Emmett, B., Kjønaas, O.J., Gundersen, P., Koopmans, C., Tietema, A., and Sleep, D. 1998. Natural abundance of 15N in forests across a nitrogen deposition gradient, Forest Ecology and Management 101:9-18.

Emmett, B., Reynolds, B., Silgram, M., Sparks, T.H., and Woods, C.. 1998. The consequences of chronic nitrogen additions on N cycling and soilwater chemistry in a Sitka spruce stand, North Wales. Forest Ecology and Management 101:165-175.

 
 
Adirondack Manipulation and Modeling Project Sites, New York, USA

Mitchell, M.J. 2001. Linkages of nitrate losses in watersheds to hydrological processes. Hydrological Processes 15:3305-3307.

Mitchell, M.J. 2001. Researching the effects of air pollution on forest, water ecosystems. Spruce Moose (Adirondack Ecological Center, SUNY-ESF, Newcomb, NY 12852) Fall/Winter 2001:2-3.

Mitchell, M.J., Driscoll, C.T., Owen, J., Schaefer, D., Michener, R., and Raynal, D.J. 2001. Nitrogen biogeochemistry of three hardwood forest ecosystems in the Adirondack Mountains. Biogeochemistry 56: 93-133.

Mitchell, M.J., Driscoll, C.T., Porter, J.H., Raynal, D.J., Schaefer, D., and White, E.H. 1994. The Adirondack Manipulation and Modeling Project (AMMP): design and preliminary results. Forest Ecology and Management 68:87-100.

 
Alptal, Switzerland (NITREX)

Hagedorn, F., Bucher, J.B., and Schleppi, P. 2001. Contrasting dynamics of dissolved inorganic and organic nitrogen in soil and surface waters of forested catchments with Gleysols. Geoderma 100:173-192.

Mohn, J., Schürmann, A., Hagedorn, F., Schleppi, P., and Bachofen, R. 2000. Increased rates of denitrification in nitrogen-treated forest soils. Forest Ecology and Management 137:113-119.

Schleppi, P., Bucher-Wallin, I., Siegwolf, R., Saurer, M., Muller, N., and Bucher J.B. 1999. Simulation of increased nitrogen deposition to a montane forest ecosystem: partitioning of the added 15N. Water, Air, and Soil Pollution 116:129-134.

Tietema, A., Boxman, A.W., Bredemeier, M., Emmett, B.A., Moldan, F., Gundersen, P., Schleppi, P., and Wright, R.F. 1998. Nitrogen saturation experiments (NITREX) in coniferous forest ecosystems in Europe: a summary of results. Environmental Pollution 102(S1):433-437.

Tietema, A., Wright, R.F., Blanck, K., Boxman, A.W., Bredemeier, M., Emmett, B.A., Gundersen, P., Hultberg, H., Kjønaas, O.J., Moldan, F., Roelofs, J.G.M., Schleppi, P., Stuanes, A.O., and Van Breemen, N., 1995. NITREX: the timing of response of coniferous forest ecosystems to experimentally-changed nitrogen deposition. Water, Air, and Soil Pollution 85:1623-1628.

Dinghushan

Fang, Yun-Ting, Yoh, M., Mo, Jiang-Ming, Gundersen, P., and Zhou, Guo-Yi. Response of nitrogen leaching to simulated nitrogen deposition in a disturbed and a mature forest in Southern China. Pedosphere (in press).

Fang, Y.T., Zhu, W.X., Mo, J.M., Zhou, G.Y., and Gundersen, P. .2006. .Dynamics of soil inorganic nitrogen and their responses to nitrogen additions in three subtropical forests, south China. Journal of Environmental Science-China 18:752-759.

Guoliang ,Xu, Jiang-ming, Mo, Shenglei, Fu, Xing, Ke , Per, Gundersen, Guoyi, Zhou, and Jinghua Xue. The response of soil fauna to simulated nitrogen deposition-a nursery experiment in subtropical China. Journal of Environmental Sciences (in press).

Guoliang, Xu, Mo, Jiang-Ming, and Zhou, Guo-Yi. 2006. Preliminary response of soil fauna to simulated N deposition in three typical subtropical forests. Pedosphere, 16(5): 596-601.

Jiangming, Mo, Wei, Zhag, Weixing, Zhu, Yunting, Fang, Dejun, Li, and Ping, Zhao. Response of soil respiration to simulated N deposition in a disturbed and a rehabilitated tropical forest in southern China. Plant and Soil (in press).

Lu, Xian-Kai, Mo, Jiang-Ming, Per, Gundersern, Zhu, Wei-Xing, Zhou, Guo-Yi, Li, De-Jun, and Zhang, Xu. Effects of simulated N deposition on soil exchangeable cations in three forest land-use types in Subtropical China. Pedosphere (in press).

Mo, J.M., Brown, S., Xue, J.H., Fang, Y.T., and Li, Z.A. 2006. Response of litter decomposition to simulated N deposition in disturbed, rehabilitated and mature forests in subtropical China. Plant and Soil 282:135-151.

Mo, J.M., Brown, S., Xue, J.H., Fang, Y.T., Li, Z.A., Li, D.J., and Dong, S.F. 2007. Response of nutrient dynamics of decomposing pine (Pinus massoniana) needles to simulated N deposition in a disturbed and a rehabilitated forest in tropical China. Ecological Research (in press). DOI 10.1007/s11284-006-0317-0.

Fernow

Adams, M. B. and Angradi, T. R. 1996. Decomposition and nutrient dynamics of hardwood leaf litter in the Fernow whole-watershed acidification experiment. Forest Ecology and Management 83:61-69.

Adams, Mary Beth, Angradi, Ted R., and Kochenderfer, James N. 1997. Stream water and soil solution responses to 5 years of nitrogen and sulfur additions at the Fernow Experimental Forest, West Virginia. Forest Ecology and Management 95:79-91.

Adams, Mary Beth, DeWalle, David R., and Hom, John L., eds. 2006. The Fernow Watershed Acidification Study. Springer. 279 p.

Adams, M.B., Edwards, P.J., Wood, F., and Kochenderfer, J.N. 1993. Artificial watershed acidification on the Fernow Experimental Forest, USA. Journal of Hydrology 150:505-519.

Adams, M.B., Kochenderfer, J.N., Angradi, T.R., and Edwards, P.J. 1995. Nutrient budgets of two watersheds on the Fernow Experimental Forest. In: Gottschalk, Kurt W. and Fosbroke, Sandra L.C. (eds.). Proceedings, 10th Central Hardwood Forest Conference. 1995 March 5-8; Morgantown, WV. U.S. Department of Agriculture, Forest Service, Northeastern Forest Experiment Station. General Technical Report NE-197:119-130.

DeWalle, David R., Tepp, Jeffrey S., Pickens, Callie J., Edwards, Pamela J., and Sharpe, William E. 1995. Tree-ring chemistry response in black cherry to ammonium sulfate fertilization at two West Virginia sites. In: Gottschalk, Kurt W. and Fosbroke, Sandra L.C. (eds._. Proceedings, 10th Central Hardwood Forest Conference. 1995 March 5-8; Morgantown, WV. U.S. Department of Agriculture, Forest Service, Northeastern Forest Experiment Station. General Technical Report NE-197:179-187

Edwards, Pamela J. and Williard, Karl W.J. 2006. Declines in soil-water nitrate in nitrogen-saturated watersheds. Canadian Journal of Forest Research 36:1931-1942.

Gilliam, Frank S., Lyttle, Nikki L., Thomas, Ashley, and Adams, Mary Beth. 2005. Soil variability along a nitrogen mineralization and nitrification gradient in a nitrogen-saturated hardwood forest. Soil Science Society of America Journal 69:247-256.

May, Jeffrey D., Burdette, Sarah Beth, Gilliam, Frank S., and Adams, Mary Beth. 2005. Interspecific divergence in foliar nutrient dynamics and stem growth in a temperate forest in response to chronic nitrogen inputs. Canadian Journal of Forest Research 35:1023-1030.

Peterjohn, William T., Foster, Cassie J., Christ, Martin J., Adams, Mary B. 1999. Patterns of nitrogen availability within a forested watershed exhibiting symptoms of nitrogen saturation. Forest Ecology and Management 119(1999):247-257.

Williard, Karl W. J., DeWalle, David R., and Edwards, Pamela J. 2005. Influence of bedrock geology and tree species composition on stream nitrate concentrations in mid-Appalachian forested watersheds. Water, Air, and Soil Pollution 160:55-76.

Harvard Forest

Aber, J., McDowell, W., Nadelhoffer, K., Magill, A., Bernston, G., Kamakea, M., McNulty, S., Currie, W., Rustad, L., and Fernandez, I. 1998. Nitrogen saturation in temperate forest ecosystems: Hypotheses revisited. Bioscience 48: 921-934.

Aber, J.D., Magill, A., and Boone, R. 1993. Plant and soil responses to chronic nitrogen additions at the Harvard forest, Massachusetts. Ecol. Appl. 3: 156-166.

Aber, J., Ollinger, S., and Driscoll, C. 1997. Modeling nitrogen saturation in forest ecosystems in response to land use and atmospheric deposition. Ecological Modelling 101: 61-78.

Currie, W., Aber, J., and Driscoll, C. Leaching of nutrient cations from the forest floor: effects of nitrogen saturation in two long-term manipulations. Can. J. For. Res. 29:609-620.

Magill, A.H., Aber, J.D., Berntson, G.M., McDowell, W.H., Nadelhoffer, K.J., Melillo, J.M., and Steudler, P. 2000. Long-term nitrogen additions and nitrogen saturation in two temperate forests. Ecosystems 3: 238-253.

Magill, A.H. and Aber, J.D. 1998. Long-term effects of experimental nitrogen additions on foliar litter decay and humus formation in forest ecosystems. Plant and Soil 203: 301-311.

Magill, A.H., Aber, J.D., Hendricks, J.J., Bowden, R.D., Melillo, J.M., and Steudler, P.A. 1997. Biogeochemical response of forest ecosystems to simulated chronic nitrogen deposition. Ecological Appl. 7: 402-415.

Huntington Forest

Christopher, S.F., Mitchell, M.J., McHale, M.R., Boyer, E.W., Burns, D.A., and Kendall, C.. 2007. Factors controlling nitrogen release from two forested catchments with contrasting hydrochemical responses. Hydrological Processes (in press).

Driscoll, C.T., Driscoll, K.M., Mitchell, M.J., Raynal, D.J., and Roy, K. 2006. Effects of atmospheric deposition of strong acids and mercury on forest and aquatic ecosystems in the Adirondack region of New York State. In: Porter, W.P., Whaley, R.S., and Erickson, J.D. (eds.). Light from an Adirondack Prism: The Great Experiment in Conservation Syracuse University Press, Syracuse, NY (in press).

Ito, M., Mitchell, M.J., Driscoll, C.T., Newton, R.M., Johnson, C.E., and Roy, K.M. 2007. Controls on nitrogen solutes in two lake-watersheds in the Adirondack region of New York. Hydrological Processes 21:1249-1264.

Ito, M., Mitchell, M.J., Driscoll, C.T., and Roy, K.M. 2005a. Nitrogen input-output budgets for lake-watersheds in the Adirondack region of New York. Biogeochemistry 72:283-314.

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