Researchers in the Multiple Element Limitation in Northern Hardwood Ecosystems (MELNHE) project are studying N and P acquisition and limitation through a series of nutrient manipulations in northern hardwood forests. This project is supported by the National Science Foundation, and builds upon the Northern Hardwood Forest Calcium Cycling Project, which established our sites at Bartlett. The project has also been called the Shoestring Project, during the period of unfunded effort between major research grants.
Although temperate forests are generally thought of as N-limited, resource optimization theory predicts that ecosystem productivity should be co-limited by multiple nutrients. These ideas are represented in the Multi-Element Limitation (MEL) model (Rastetter et al. 2012). To test the patterns of resource limitation predicted by MEL, we are conducting nutrient manipulations in three study sites in the White Mountain National Forest in New Hampshire: Bartlett Experimental Forest, Hubbard Brook Experimental Forest, and Jeffers Brook.
At Bartlett, we have three replicate stands of three ages, young (clearcut 1985-1990), mid-aged (clearcut 1975-1978), and mature (clearcut 1883-1890). At Hubbard Brook and Jeffers Brook, we have stands that correspond to the mid-aged and mature stands at Bartlett, for 4 more stands. Each of the 13 stands has four 1/4 ha (50 m x 50 m) treatment plots, treated annually each spring beginning in 2011, with N (30 kg N/ha/yr as NH4NO3), P (10 kg P/ha/yr as NaH2PO4), N+P, or nothing (an untreated control). Five stands also have a Ca treatment plot (1150 kg Ca/ha in the form of CaSiO3).
We are monitoring stem diameter, leaf litter production and nutrient flux, foliar chemistry and nutrient resorption, canopy reflectance, sap flow, root biomass and production, mycorrhizal associations, soil respiration, soil N and P availability, N mineralization, soil phosphatase activity, soil carbon and nitrogen, and bird activity. See highlights below for our results to date!
The MELNHE project is currently funded by USDA National Institute of Food and Agriculture (2019-67019-29464) and NSF Long-Term Ecological Research (DEB-1637685).
NSF previously supported Biotic control of calcium supply: Distinguishing sources to regrowing forests (DEB-0235650), Nutrient co-limitation in young and mature northern hardwood forests (MELNHE) (DEB-0949324 to ESF and collaborative grants to MBL, Miami University, Cornell University, and University of Michigan), and Long-Term Ecological Research grants to the Hubbard Brook Ecosystem Study (DEB-1114804 and DEB-0423259).
MELNHE is led by 3 principal investigators...
- Ruth Yanai , SUNY College of Environmental Science and Forestry, Syracuse, NY
- Melany Fisk , Miami University of Ohio, Oxford, OH
- Tim Fahey, Cornell University, Ithaca, NY
with a host of additional collaborators, including graduate students, technicians, undergraduate students, high school teachers and visiting scientists.
- Hubbard Brook Ecosystem 58th Annual Cooperators' Meeting, July 7-8, 2021
- Are we there yet? 10 years into the N by P manipulation study.Ruth Yanai
- Mycorrhizae and Increasing N Limitation in Northern Hardwood Forests Noah Blumenthal
- Herbaceous and Vivacious: How do ground layer plants respond to N by P fertilization? Scott Dai
- Community-level leaf traits with forest succession and nutrient addition. Jenna Zukswert
- The Effect of Mesh Size on Litter Decomposition Rates in Northern Hardwood Forests. Brianne Innusa
- Composition affecting Decompositin: A reciprical transplant litter decomposition study. Emelia Sargent
- Sampling the mycorrhizal community with pine seedlings. Cathy Fahey
- Revealing Their True Collars: Are soil respiration measurements influenced by collar aging? Isaac Roter
- Isn't 150 years old? Woody debris in the Anthropocene. Joe Nash
- Resampling beech bark disease severity over time in a chronosequence. Erin Cornell
- Beech Baby Boom: Beech sprout interference with sugar maple regeneration. April Zee
Watch Alex Young's presentation, Temperate forest structural metrics respond to N & P addition.
Posters presented at the ESA's (Virtual) Annual Meeting, August 3-6, 2020
Gonzales, K.E., D.S. Hong, and R.D. Yanai. Foliar N and P concentrations of six northern hardwood species in three age classes in a factorial N and P addition experiment in the White Mountains of New Hampshire
Mann, T.A., S. Goswami, R.D. Yanai, and K. Bazany. Nitrogen and phosphorus affect the density of sugar maple and American beech germinants
Yanai, R.D., K.E. Gonzales, D.S. Hong, M.C. Fisk, and T.J. Fahey. Does foliar N:P predict nutrient limitation in six northern hardwood species?
Young, A.R., A.K. Schweiger, M.C. Fisk, and R.D. Yanai. Detecting foliar nutrient status of northern hardwoods from the sky
Hubbard Brook Ecosystem Study 57th Annual Cooperators' Meeting (July 7-9, 2020) Presentations
- Research Opportunites
Gretchen Dillon, Dan Hong and Alex Rice's theses:
- Dillon, Gretchen A. Nutritional effect on causal organisms of beech bark disease in an aftermath forest. PDF
- Hong, Daniel S. Effects of nitrogen and phosphorus addition on foliar nutrient concentrations of six northern hardwood species. PDF
- Rice, Alexandrea M. Tree variability limits the detection of nutrient treatment effects on sap flow in a northern hardwood forest. PDF
- It has been a busy 2 weeks, three graduates in one semester! Watch their capstone presentations.
- Dan Hong. Effects of nitrogen and phosphorus addition on foliar nutrient concentrationsof six northern hardwood species. December 17, 2019
- Alex Rice. From trees to trails: A research series. December 16, 2019
- Gretchen Dillion. Nutritional effects on casual organisms of beech bark disease in an aftermath forest. December 2, 2019.
Alex Rice presents a poster at the American Society of Agronomy-Crop Science Society of America-Soil Science Society of America International Annual Meeting, November 10-13, 2019, San Antonio, TX
- Rice, A.M., M.A. Vadeboncoeur, and R.D. Yanai. Relating soil nutrients to ecosystem fluxes. Poster
- NEW Leaf ID Guide PDF
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