In summer 1992, isoprene emission was measured on intact leaves and branches of Quercus alba (L.) at two heights in a forest canopy. Isoprene emission capacity (measured at 30 °C… More
The unabated increase in global atmospheric CO2 is expected to induce physiological changes in plants, including reduced foliar nitrogen, which are likely to affect herbivore densities. This study employs a… More
We measured the stable isotope ratio of respired carbon dioxide at two spatial scales in a black spruce forest in northern Canada: CO2 released from the forest floor and CO2… More
Continuous measurements of whole canopy isoprene emissions over an entire growing season are reported from Harvard Forest (42°32′N, 72°11′W). Emissions were calculated from the ratio of observed CO2 flux and… More
Eddy covariance measurements were made in seven fields in the Midwest USA over 4 years (including the 2012 drought year) to estimate evapotranspiration (ET) of newly established rain-fed cellulosic and grain… More
Net photosynthesis was measured under field conditions in 23-year-old slash pine (Pinus elliottii Engelm. var. elliottii) trees to determine how it was affected by fertilization and climate. There was only… More
We used eddy covariance to measure the net exchange of CO2 between the atmosphere and a black spruce (Picea mariana) forest in Manitoba for 16,500 hours from March 16, 1994… More
Recent and long-term accumulation rates of carbon (C), using 210Pb- and 14C-dating, were examined in 23 ombrotrophic peatlands in eastern Canada, where average 1990–1996 atmospheric wet nitrogen (N) deposition ranged… More
Radon-222 (Rn-222) is used as a transport tracer of forest canopy–atmosphere CO2 exchange in an old-growth, tropical rain forest site near km 67 of the Tapajós National Forest, Pará, Brazil…. More
Agriculture is a resource-intensive enterprise. The manner in which food production systems utilize resources has a large influence on environmental quality. To evaluate prospects for conserving natural resources while meeting… More