Physical Sciences and Mathematics Commons^™

Soil Denitrification Fluxes From Three Northeastern North American Forests Across A Range Of Nitrogen Deposition, Jennifer Morse, Jorge Durán, Fred Beall, Eric Enanga, Irena Creed, Ivan Fernandez, Peter Groffman

Ivan J. Fernandez

In northern forests, large amounts of missing N that dominate N balances at scales ranging from small watersheds to large regional drainage basins may be related to N-gas production by soil microbes. We measured denitrification rates in forest soils in northeastern North America along a N deposition gradient to determine whether N-gas fluxes were a significant fate for atmospheric N inputs and whether denitrification rates were correlated with N availability, soil O2 status, or forest type. We quantified N2 and N2O fluxes in the laboratory with an intact-core method and monitored soil O2, temperature and moisture in three forests differing …

Maine's Climate Future: An Initial Assessment, George Jacobson, Ivan Fernandez, Paul Mayewski, Catherine Schmitt

Ivan J. Fernandez

Earth’s atmosphere is experiencing unprecedented changes that are modifying global climate. Discussions continue around the world, the nation, and in Maine on how to reduce and eventually eliminate emissions of carbon dioxide (CO2), other greenhouse gases, and other pollutants to the atmosphere, land, and oceans. These efforts are vitally important and urgent. However, even if a coordinated response succeeds in eliminating excess greenhouse gas emissions by the end of the century, something that appears highly unlikely today, climate change will continue, because the elevated levels of CO2 can persist in the atmosphere for thousands of years to come.

In late …

Tb134: A Laboratory Study To Assess Methods For Predicting Ph Change Of Ash Amended Forest Soils, Yvonne Unger, Ivan Fernandez

Ivan J. Fernandez

The objective of this study was to compare several commonly used lime requirement tests and soil capacity factors for their ability to predict pH change following wood-ash amendment. The ability to predict pH change is important because it is one of the criteria used to prescribe rates of ash amendment to forest soils.

Tb164: Precipitation Chemistry At The Greenville, Maine, Nadp/Ntn Station, Ivan Fernandez, Llew Wortman

Ivan J. Fernandez

This report details results from the Greenville, Maine, NADP/NTN site supported by the Maine Agricultural and Forest Experiment Station. The site is located in Piscataquis County at 69°39'52" longitude and 45°29'23" latitude at approximately 322 m elevation. The site consists of a single Aerochem Metrics® Automatic Sensing Wet/Dry Precipitation Collector that provides samples for chemical analysis and a Belfort® Recording Rain Gage and Event Recorder for accurate determinations of precipitation volume. Samples are collected every Tuesday morning 52 weeks a year.