Sap Flow 2015:

Does N or P also affect water use in the MELNHE

plots? Brigid Farrell Isaac Jo

Jessie Smith Nick Hodom

Shoestring/MELNHE ProjectSUNY-ESF

Background• Both N and P may co-limit primary

production (Rastetter et al., 2013)• Simultaneous additions of N and P

yielded synergistic improvements in primary production (Elser et al., 2007)• Growth responses of separate additions

of N and P are indistinguishable (Elser et al., 2007)• Ca additions increase forest

evapotranspiration (Green et al., 2013)

Objectives

• Analyze effects of nutrient additions (N, P, N&P, and Ca) by comparing sap flow between treatment plots• Test N&P colimitation within

the context of resource optimization theory

Methods

• Ca, N, P, N&P, and control plots in 2 different aged stands over 10 day period• Granier method to estimate sap

flow • Baseliner software used to

transform data

Preliminary Results

Preliminary Results

Citations• Elser, J. J., Bracken, M. E., Cleland, E. E., Gruner, D. S., Harpole,

W. S., Hillebrand, H., Smith, J. E. (2007). Global analysis of nitrogen and phosphorus limitation of primary producers in freshwater, marine and terrestrial ecosystems. Ecology Letters, 10, 1135-1142.• Green, M. B., Bailey, A. S, Bailey, S. W., Battles, J. J., Campbell, J.

L., Driscoll, C. T., . . . Schaberg, P. G. (2013). Decreased water flowing from a forest amended with calcium silicate. Proceedings of the National Academy of Sciences, 110(15), 5999-6003.• Rastetter, E.B., Yanai, R. D., Thomas, R. Q., Vadeboncoeur, M. A.,

Fahey, T. J., Fisk, M. C.. Hamburg, S. P. (2013). Recovery from disturbance requires resynchronization of ecosystem nutrient cycles. Ecological Applications, 23(3), 621-642.

Acknowledgments

• Sophie Harrison• Mariann Johnston• Michele Pruyn• Matt Vadeboncoeur• Ruth Yanai• Jerome Barner• Shoestring Crew