Summer drought is a feature of the semi-arid region of central Oregon, USA, where vegetation naturally develops into ponderosa pine (Pinus ponderosa var. Laws) forest. Forest management consists of clearcut harvest and natural regeneration. Soil microbial activity …
Journal: Forest Ecology And Management, Volume 191 (1-3): 201-213 (2004). DOI: 10.1016/j.foreco.2003.12.005 Sites: US-Me2
Continuous automatic chamber and eddy covariance (EC) measurements were made at an old aspen forest (SOA) located at southern boreal treeline in Saskatchewan, Canada to examine the temporal variability in soil (Rs), tree bole (Rb), and ecosystem respiration (RE) during 2001. …
Journal: Agricultural And Forest Meteorology, Volume 125 (3-4): 207-223 (2004). DOI: 10.1016/j.agrformet.2004.04.006 Sites: CA-Oas
We used estimates of autotrophic respiration (RA), net primary productivity (NPP) and soil CO2 evolution (Sff), to develop component carbon budgets for 12-year-old loblolly pine plantations during the fifth year of a fertilization and irrigation experiment. Annual carbon use in RA …
Journal: Global Change Biology, Volume 10 (8): 1335-1350 (2004). DOI: 10.1111/j.1529-8817.2003.00809.x Sites: US-Dk3
Ecosystem ozone uptake can occur through stomatal and surface deposition and through gas phase chemical reactions. In a California pine forest, thinning dramatically enhanced both monoterpene emission and ozone uptake. These simultaneous enhancements provide strong evidence that ozone reactions with unmeasured biogenically emitted …
Journal: Geophysical Research Letters, Volume 31 (22): n/a-n/a (2004). DOI: 10.1029/2004gl021259 Sites: US-Blo
Understanding how tropical forest carbon balance will respond to global change requires knowledge of individual heterotrophic and autotrophic respiratory sources, together with factors that control respiratory …
Journal: Ecological Applications, Volume 14 (sp4): 72-88 (2004). DOI: 10.1890/01-6012 Sites: BR-Ma2, BR-Sa1, BR-Sa3
A new maize (Zea mays L.) simulation model, Hybrid-Maize, was developed by combining the strengths of two modeling approaches: the growth and development functions in maize-specific models represented by CERES-Maize, and the mechanistic formulation of photosynthesis and respiration in generic crop models such as INTERCOM …
Journal: Field Crops Research, Volume 87 (2-3): 131-154 (2004). DOI: 10.1016/j.fcr.2003.10.003 Sites: US-Ne1, US-Ne2, US-Ne3
Net ecosystem CO2 exchange (NEE) was measured in maize-based agroecosystems in eastern Nebraska, USA, during the growing season in 2001. The objective of this study was to quantify and contrast NEE in irrigated and rainfed maize (Zea maize L.) fields. …
Journal: Agricultural And Forest Meteorology, Volume 124 (1-2): 1-13 (2004). DOI: 10.1016/j.agrformet.2004.01.011 Sites: US-Ne1, US-Ne2, US-Ne3
Missing data is a ubiquitous problem in evaluating long-term experimental measurements, such as those associated with the FluxNet project, due to the equipment failures, system maintenance, power-failure, and lightning strikes among other things. To estimate annual values …
Journal: Agricultural And Forest Meteorology, Volume 121 (1-2): 93-111 (2004). DOI: 10.1016/s0168-1923(03)00158-8 Sites: US-Dk3, US-NR1, US-WBW
Turbulent fluxes of carbon, water vapor, and temperature were continuously measured above an upland forest in north central Wisconsin during 1999 and 2000 using the eddy covariance method. Maple (Acer saccharum), basswood (Tilia americana), and green ash (Fraxinus pennsylvanica) species found in this forest …
Journal: Agricultural And Forest Meteorology, Volume 126 (3-4): 271-295 (2004). DOI: 10.1016/j.agrformet.2004.06.008 Sites: US-Los, US-PFa, US-WCr
Models used to estimate net ecosystem productivity (NEP) during climate change should first be shown to simulate the effects on NEP of interannual variability in current climates. Energy and CO2 fluxes simulated by the ecosystem model ecosys were compared …
Journal: Agricultural And Forest Meteorology, Volume 126 (1-2): 99-116 (2004). DOI: 10.1016/j.agrformet.2004.06.005 Sites: CA-Let