Publications

Publications Found: 49
On The Correct Estimation Of Effective Leaf Area Index: Does It Reveal Information On Clumping Effects?
Ryu, Y., Nilson, T., Kobayashi, H., Sonnentag, O., Law, B. E., Baldocchi, D. D.

Effective leaf area index is routinely quantified with optical instruments that measure gap fraction through the probability of beam penetration of sunlight through the vegetation. However, there have been few efforts to obtain theoretically consistent effective leaf area …


Journal: Agricultural And Forest Meteorology, Volume 150 (3): 463-472 (2010), ISBN . DOI: 10.1016/j.agrformet.2010.01.009 Sites: US-Ton

Plant-Soil Interactions And Acclimation To Temperature Of Microbial-Mediated Soil Respiration May Affect Predictions Of Soil CO2 Efflux
Curiel Yuste, J., Ma, S., Baldocchi, D. D.

It is well known that microbial-mediated soil respiration, the major source of CO2 from terrestrial ecosystems, is sensitive to temperature. Here, we hypothesize that some mechanisms, such as acclimation of microbial respiration to temperature and/or regulation by plant fresh C inputs of the temperature sensitivity of …


Journal: Biogeochemistry, Volume 98 (1-3): 127-138 (2010), ISBN . DOI: 10.1007/s10533-009-9381-1 Sites: US-Ton

Observations And Stochastic Modeling Of Soil Moisture Control On Evapotranspiration In A Californian Oak Savanna
Chen, X., Rubin, Y., Ma, S., Baldocchi, D.

The study of water exchange between soil, plants, and the atmosphere in response to seasonal or periodic droughts is critical to modeling the hydrologic cycle and biogeochemical processes in water-controlled ecosystems. An essential step in such studies is to characterize changes in evaporation and transpiration under water stress. …


Journal: Water Resources Research, Volume 44 (8): n/a-n/a (2008), ISBN . DOI: 10.1029/2007wr006646 Sites: US-Ton

Modeling Radiation And Photosynthesis Of A Heterogeneous Savanna Woodland Landscape With A Hierarchy Of Model Complexities
Chen, Q., Baldocchi, D., Gong, P., Dawson, T.

Simple but realistic modeling of radiation transfer within heterogeneous canopy has been a challenging research question for decades and is critical for predicting ecological processes such as photosynthesis. The Markov model proposed by [Nilson, T., 1971. A theoretical analysis of the frequency of gaps in plant stands. Agric. Meteorol. …


Journal: Agricultural And Forest Meteorology, Volume 148 (6-7): 1005-1020 (2008), ISBN . DOI: 10.1016/j.agrformet.2008.01.020 Sites: US-Ton

Inter-Annual Variability In Carbon Dioxide Exchange Of An Oak/Grass Savanna And Open Grassland In California
Ma, S., Baldocchi, D. D., Xu, L., Hehn, T.

To understand the dynamics of ecosystem carbon cycling, CO2 fluxes were measured over and under an oak–grass savanna and over a proximate grassland in California. The measurements were made from 2000 to 2006 using the eddy covariance technique. Annual net carbon exchange (NEE) ranged from −155 to −56 gC m−2 year−1


Journal: Agricultural And Forest Meteorology, Volume 147 (3-4): 157-171 (2007), ISBN . DOI: 10.1016/j.agrformet.2007.07.008 Sites: US-Ton, US-Var

What The Towers Don'T See At Night: Nocturnal Sap Flow In Trees And Shrubs At Two Ameriflux Sites In California
Fisher, J. B., Baldocchi, D. D., Misson, L., Dawson, T. E., Goldstein, A. H.

At the leaf scale, it is a long-held assumption that stomata close at night in the absence of light, causing transpiration to decrease to zero. Energy balance models and evapotranspiration equations often rely on net radiation as an upper bound, and some models reduce evapotranspiration to zero at night when there is no solar radiation. …


Journal: Tree Physiology, Volume 27 (4): 597-610 (2007), ISBN . DOI: 10.1093/treephys/27.4.597 Sites: US-Ton

Filtering Airborne Laser Scanning Data With Morphological Methods
Chen, Q., Gong, P., Baldocchi, D., Xie, G.

Filtering methods based on morphological operations have been developed in some previous studies. The biggest challenge for these methods is how to keep the terrain features unchanged while using large window sizes for the morphological opening. Zhang et al. (2003) tried to achieve this goal, but their method required the assumption …


Journal: Photogrammetric Engineering & Remote Sensing, Volume 73 (2): 175-185 (2007), ISBN . DOI: 10.14358/pers.73.2.175 Sites: US-Ton

Estimating Basal Area And Stem Volume For Individual Trees From Lidar Data
Chen, Q., Gong, P., Baldocchi, D., Tian, Y. Q.

This study proposes a new metric called canopy geometric volume G, which is derived from small-footprint lidar data, for estimating individual-tree basal area and stem volume. Based on the plant allometry relationship, we found that basal area B is exponentially related to G (B = β1G3/4, where β1


Journal: Photogrammetric Engineering & Remote Sensing, Volume 73 (12): 1355-1365 (2007), ISBN . DOI: 10.14358/pers.73.12.1355 Sites: US-Ton

What Limits Evaporation From Mediterranean Oak Woodlands – The Supply Of Moisture In The Soil, Physiological Control By Plants Or The Demand By The Atmosphere?
Baldocchi, D. D., Xu, L.

The prediction of evaporation from Mediterranean woodland ecosystems is complicated by an array of climate, soil and plant factors. To provide a mechanistic and process-oriented understanding, we evaluate theoretical and experimental information on water loss of Mediterranean oaks at three scales, the leaf, tree and woodland. …


Journal: Advances In Water Resources, Volume 30 (10): 2113-2122 (2007), ISBN . DOI: 10.1016/j.advwatres.2006.06.013 Sites: US-Ton

Upscaling Fluxes From Tower To Landscape: Overlaying Flux Footprints On High-Resolution (IKONOS) Images Of Vegetation Cover
Kim, J., Guo, Q., Baldocchi, D., Leclerc, M., Xu, L., Schmid, H.

In this paper, we describe the process of assessing tower footprint climatology, spatial variability of site vegetation density based on satellite image analysis, and sensor location bias in scaling up to 1 km × 1 km patch. Three flat sites with different vegetation …


Journal: Agricultural And Forest Meteorology, Volume 136 (3-4): 132-146 (2006), ISBN . DOI: 10.1016/j.agrformet.2004.11.015 Sites: US-SP1, US-Ton, US-Var