Dale Johnson and Timothy Ball, Desert Research Institute, and Roger Walker, University of Nevada
Prepared by: Bob Cushman, CDIAC

NDP-061A (1998)

This data package presents measured values of plant diameter and height, biomass of plant components, and nutrient (carbon, nitrogen, phosphorus, sulfur, potassium, calcium, magnesium, boron, copper, iron, manganese, and zinc) concentrations from a study of the effects of carbon dioxide and nitrogen fertilization on ponderosa pine conducted in open-top chambers in Placerville, California, from 1991 through 1996, funded by DOE and other agencies. This data set contains values from 1991 through 1993.

These data may be used to study the effect that elevated levels of atmospheric carbon dioxide in combination with various levels of nitrogen fertilization have on the growth and nutrient content of ponderosa pine, an important timber species of western North America. Johnson et al. used the data documented in this numeric data package to evaluate two hypotheses: (1) that elevated CO₂ would increase growth and yield of biomass per unit uptake of N even if N is limiting, and (2) that elevated CO₂ would increase biomass yield per unit uptake of other, nonlimiting nutrients only by growth dilution.

This database can help quantify the response of vegetation to rising atmospheric concentrations of carbon dioxide caused by fossil-fuel combustion and land-use change. WDC-A database

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kng 01/99