Ruth Yanai's Research--completed projects

Completed Projects

Biotic control of calcium cycling

Mary Arthur, University of Kentucky; Joel Blum, University of Michigan; Melany Fisk, Appalachian State University; Steven Hamburg, Brown University; Elizabeth Hane, Rochester Institute of Technology; and Ruth Yanai, SUNY-ESF

We are looking at differences in Ca cycling with stand age, and determing the source of Ca mobilized from mineral soil in young stands. Hypothesis testing uses both an extensive approach, involving 13 previously studied stands, and intensive one using replicate stands of three ages at a single site. The Northern Hardwood Calcium Project is now part of the Multiple Element Limitation in Northern Hardwood Ecosystems (MELNHE) project

Read More:

Blum, J., A.A. Dasch, S.P. Hamburg, R.D.Yanai, and M.A. Arthur. 2008. Use of foliar Ca/Sr discrimination and 87Sr/86Sr ratios to determine soil Ca sources to sugar maple foliage in a northern hardwood forest. Biogeochemistry 87(3):287-296 PDF From SU/ESF: HTML

Yanai, R.D., J.D. Blum, S.P. Hamburg, M.A. Arthur, C.A. Nezat, T.G. Siccama. 2005. New insights into calcium depletion in northeastern forests. Journal of Forestry. 103: 14-20. PDF

Yanai, R.D., R.P. Phillips, M.A. Arthur, T.G. Siccama, and E. Hane. 2005. Spatial and temporal variation in calcium and aluminum in northern hardwood forest floors. Water, Air, and Soil Pollution. 160: 109-118. PDF

Hamburg, S,P., R.D. Yanai, M.A. Arthur, J.D. Blum and T.G. Siccama. 2003. Biotic control of calcium cycling in northern hardwood forests: acid rain and aging forests. Ecosystems 6: 399-404. PDF

Sources of Calcium in Northern Hardwood Forests: Implications for Repeated Harvests and Calcium Depletion

Ruth Yanai, SUNY-ESF; Joel Blum, University of Michigan; Steven Hamburg, Brown University; Mary Arthur, University of Kentucky

We collected and analyzed soil samples from a total of 24 sites in Maine, New Hampshire (all 14 located in the White Mountain National Forest), New York and Pennsylvania: The results of this work have been surprising.

First, we found that apatite is indeed an important source of Ca in soils in rocks derived from granitoid parent materials, but it is less important in sedimentary rocks. One paper, published in the Journal of Forestry in 2005, describes this finding, and another is in preparation by Carmen Nezat, which treats the subject in more detail.

The method for identifying apatite in soils is an important product of this research. Another manuscript has recently been submitted soon to Chemical Geology describing the sequential extraction procedure we developed, also led by Carmen Nezat.

We had intended to describe the relative importance of apatite as a calcium source in stands of different ages and species composition by comparing the composition of tree foliage to that of the major Ca sources, using trace metals and isotopes. This analysis is not as simple as we had hoped, because trees fractionate strontium and calcium, and tree species differ in the degree to which they do so. Amanda Dasch is preparing a manuscript describing this problem, and when it is completed, Joel Blum will be in a position to apply a modified approach to addressing our original question.

This project has been supported by grants from the USDA Forest Service Agenda 2020 Sustainable Forest Research program, National Science Foundation and the New York State Energy Research and Development Authority.

Read More:

Nezat, C.A., J.D. Blum, R.D. Yanai, S.P. Hamburg, and B.B. Park. 2008. Mineral sources of calcium and phosphorus in soils of the northeastern USA. Soil Science Society of America Journal 72(6): 1786–1794 PDF

Nezat, C.A., J.D. Blum, R.D. Yanai and S.P. Hamburg. 2007. A sequential extraction to selectively dissolve apatite for determination of soil nutrient pools with an application to Hubbard Brook Experimental Forest, New Hampshire, USA. Applied Geochemistry 22: 2406–2421 PDF

Yanai, R.D., J.D. Blum, S.P. Hamburg, M.A. Arthur, C.A. Nezat, T.G. Siccama. 2005. New insights into calcium depletion in northeastern forests. Journal of Forestry. 103: 14-20. PDF

NYSERDA: Assessing the sensitivity of New York Forests to cation depletion

Ruth Yanai, SUNY College of Environmental Science and Forestry and Joel Blum, University of Michigan

Information concerning the distribution of sources of calcium (Ca) and the ability of tree species to access calcium is essential for predicting the sensitivity of forests across New York State to Ca depletion resulting from acidic deposition. The data accumulated through this project will provide a more accurate assessment of the likelihood that New York State forests will be adversely affected by the depletion of calcium and other exchangeable cations. In particular, this project sought to:

Describe the distribution of Ca-bearing minerals in soil and soil parent material;

Assess the relative ability of important tree species to access Ca from various sources, including trace minerals; and

Assess how changes in soil Ca content resulting from nitrogen deposition would affect the storage of carbon in soil.

Read More:

Park, B.B., R.D. Yanai, M.A. Vadeboncoeur, and S.P. Hamburg. 2007. Estimating root biomass in rocky soils using pits, cores and allometric equations. Soil Sci. Soc. Am. J. 71:206-213. PDF

Yanai, R.D., B.B. Park, and S.P. Hamburg. 2006. The vertical and horizontal distribution of roots in northern hardwoods of varying age. Can. J. For. Res. 36(2): 450-459. PDF

A project update and draft summary report are available. As per agreement with NYSERDA, data from this study are available for subsequent study. Please request access to virtual study archives by email to forestecology@esf.edu.

Nutrient Uptake and Content

F.R. Fatemi and R.D. Yanai

M.S. Lucash, R.D. Yanai and J.D. Joslin

Plant nutrient uptake is difficult to estimate at the ecosystem scale. Several indirect methods are used to quantify stand-level nutrient uptake such as nutrient budgets and simulation models. In nutrient budgets, nutrient uptake is generally estimated by using fluxes such as litter fall, biomass accumulation, and root turnover. Simulation models, on the other hand, predict uptake utilizing measurements such as root length, soil solution concentrations, and uptake capacity.

Many studies of uptake capacity in trees have been conducted using seedlings, despite the fact that seedling uptake may differ dramatically from that of mature trees. Other studies in forest ecosystems have used excised roots to estimate uptake, even though carbohydrate and water supply is halted at the time of excision. In this study we plan to measure uptake capacity of intact roots at several sites across the US in order to improve model estimates of ecosystem uptake. Results from the simulation models will also be compared with nutrient budgets.

Nitrogen immobilization by woodchip application in a northern hardwood forest.

René Germain, SUNY College of Environmental Science and Forestry

Leaf litter immobilizes N, reducing stream export, briefly, in the fall. We have conducted a 1-year study of the potential for wood chips to immobilize N following forest harvest, to reduce the peak nitrate delivery to streams. This work is in the context of the New York City Watersheds in the Catskill Mountains of New York. To date, Forestry BMPs (Best Management Practices) have addressed sedimentation of streams, but not stream chemistry. This work could result in the development of a new BMP.

Read More: Homyak, P.M., R.D. Yanai, D.A. Burns, R.D. Briggs, and R.H. Germain. 2008. Nitrogen immobilization by wood chip application: protecting water quality in a northern hardwood forest. Forest Ecology and Management 255: 2589-2601. PDF

Nutrient Uptake Modeling

We use a steady-state model of nutrient uptake (Nye and Tinker 1977, Yanai 1994), because it allows parameters such as root length, root diameter, root length density (root length per unit soil volume), average soil solution concentration, buffer capacity, and the effective diffusion coefficient to vary over time. In natural ecosystems, root length increases and decreases seasonally, and nutrient concentrations in solution reflect processes such as mineralization, immobilization, and weathering in addition to nutrient uptake. We supply the model with values of root length, rooting density, soil solution and solid phase concentrations, transpiration rates, and soil moisture content at whatever time resolution data and depth resolution are available for each of our 6 sites (link to map of sites).

A multi-dimensional sensitivity analysis shows that the most important parameters in simulating nutrient uptake are the root length, soil solution concentration, and uptake kinetics (Williams and Yanai 1996). Uncertainty analysis will be conducted for each site by running the model repeatedly using the observed distribution of parameter values (Gardner et al. 1983). We will also test the value of time-varying input by simulating uptake using annual average values and comparing them to simulations at finer resolution.

To download the model:
http://www.esf.edu/for/yanai/models/nut

Modeling Soil Solution Chemistry: YASE

YASE is a model that simulates the chemical composition of soil solutions as determined by chemical equilibria, organic matter transformations, and mineral weathering. Different properties can be assigned to different soil layers in the model. Uptake of solutes from the soil by plants, addition of organic matter, movement of soil solution between soil layers, and influx of solution from above or below the soil can be provided as inputs to YASE, either by the TREGRO model or by the user. YASE can be run alone at any time step; when called by TREGRO it is called on a daily time step.

Chemical equilibria in YASE are based on the Chemical Equilibria in Soils and Solutions model, CHESS (Santore 1991). CHESS uses a matrix representation of solution chemistry (Morel, 1983). Equilibrium problems of any composition and complexity (or simplicity) can be simulated using this model, because the chemical components and the rules for combining them into species are supplied by the user.

Decomposition in YASE follows the algorithm of GEM (Rastetter et al., 1991): transformations among extractives, cellulose, lignin, and humus are affected by temperature, soil moisture, N availability, and a ligno-cellulose index. Weathering in YASE is defined by the user using mineral compositions, weathering rates, and reaction orders with respect to pH and the amount of mineral present. Cation exchange is treated as an equilibrium between adsorbed and dissolved species interrelated by selectivity coefficients.

YASE was developed to be compatible with TREGRO. To be used in combination with TREGRO, YASE must be parameterized to include the nutrients of possible importance to the plant. A HyperCard interface aids in the parameterization and running of the model, whether alone or in combination with TREGRO.

Nutrient Uptake using SUM Columns

M.S. Lucash, R.D. Yanai, J.D. Joslin and J.M. Scholberg

Most estimates of nutrient uptake are obtained using excised roots or roots recently excavated from soil. Using this sand-culture method, we are able to obtain estimates of nitrate and ammonium uptake of seedlings. We installed these SUM (soil uptake monitoring) columns in the field and plan to test this method using mature sugar maple and eastern hemlock in spring, 2004.

Root Growth and Developement

Sorting roots