Most satellites provide, at best, a single daily snapshot of vegetation and, at worst, these snapshots may be separated by periods of many days when the ground was obscured by cloud cover. Since vegetation carbon exchange can be very dynamic on diurnal and day-to-day timescales, the limited temporal resolution of satellite data is …
Journal: Agricultural And Forest Meteorology, Volume 131 (1-2): 1-12 (2005). DOI: 10.1016/j.agrformet.2005.04.006 Sites: CA-Let, US-Blo, US-Ho1, US-MMS, US-NR1, US-Ton, US-Var
A better understanding of forest subcanopy flows is needed to evaluate their role in the horizontal movement of scalars, particularly in complex terrain. This paper describes detailed measurements of the canopy structure and its variability in both the horizontal …
Journal: Journal Of Applied Meteorology, Volume 44 (8): 1161-1179 (2005). DOI: 10.1175/jam2265.1 Sites: US-Ha1
We characterized vertical variation in the seasonal release of stored soil moisture in old-growth ponderosa pine (OG-PP, xeric), and young and old-growth Douglas-fir (Y-DF, OG-DF, mesic) forests to evaluate changes in water availability for root uptake. Soil water potential (ψ) and volumetric water content (θ) …
Journal: Agricultural And Forest Meteorology, Volume 130 (1-2): 39-58 (2005). DOI: 10.1016/j.agrformet.2005.01.004 Sites: US-Me4
Continuous measurements of carbon flux from 1997 to 2002 by eddy-covariance were used to evaluate the carbon budget for a maize (Zea mays L.) and soybean (Glycine max (L.) Merr.) rotation agricultural ecosystem that has been in no-till cultivation for over …
Journal: Agricultural And Forest Meteorology, Volume 130 (1-2): 59-69 (2005). DOI: 10.1016/j.agrformet.2005.01.005 Sites: US-Bo1, US-Bo2
Soil CO2 efflux is a major component of net ecosystem productivity (NEP) of forest systems. Combining data from multiple researchers for larger-scale modeling and assessment will only be valid if their methodologies provide directly comparable …
Journal: Biogeochemistry, Volume 73 (1): 283-301 (2005). DOI: 10.1007/s10533-004-4022-1 Sites: US-Dk2, US-Dk3
To better understand the biotic and abiotic factors that control soil CO2 efflux, we compared seasonal and diurnal variations in simultaneously measured forest-floor CO2effluxes and soil CO2 concentration profiles in a 54-year-old Douglas fir forest on the east coast of Vancouver Island. …
Journal: Agricultural And Forest Meteorology, Volume 130 (3-4): 176-192 (2005). DOI: 10.1016/j.agrformet.2005.03.005 Sites: CA-Ca1
- Quantitative assessment of carbon (C) storage by forests requires an understanding of climatic controls over respiratory C loss. Ecosystem respiration can be estimated biometrically as the sum (RΣ) of soil (Rs), leaf (Rl) and wood (Rw) …
Journal: New Phytologist, Volume 167 (2): 437-456 (2005). DOI: 10.1111/j.1469-8137.2005.01438.x Sites: US-UMB
Chamber measurements of total ecosystem respiration (TER) in a native Canadian grassland ecosystem were made during two study years with different precipitation. The growing season (April–September) precipitation during 2001 was less than one-half of the 30-year mean (1971–2000), while 2002 received almost double the normal growing …
Journal: Agricultural And Forest Meteorology, Volume 130 (3-4): 237-253 (2005). DOI: 10.1016/j.agrformet.2005.04.002 Sites: CA-Let
To assess the relative influence of edaphoclimatic gradients and stand replacing disturbance on the soil respiration of Oregon forests, we measured annual soil respiration at 36 independent forest plots arranged as three replicates of four age classes in …
Journal: Biogeochemistry, Volume 73 (1): 109-125 (2005). DOI: 10.1007/s10533-004-5165-9 Sites: US-Me2, US-Me3, US-Me4, US-Me5
Yield maps reflect systematic and random sources of yield variation as well as numerous errors caused by the harvest and mapping procedures used. A general framework for processing of multi-year yield map data was developed. Steps included (1) raw data screening, …
Journal: Precision Agriculture, Volume 6 (2): 193-212 (2005). DOI: 10.1007/s11119-005-1035-2 Sites: US-Ne1, US-Ne2, US-Ne3