The global terrestrial carbon sink offsets one-third of the world’s fossil fuel emissions, but the strength of this sink is highly sensitive to large-scale extreme events. In 2012, the contiguous United States experienced exceptionally warm temperatures and the most severe drought since the Dust Bowl era of the 1930s, resulting …
Journal: Proceedings of the National Academy of Sciences, Volume 113 (21): 5880-5885 (2016). DOI: 10.1073/pnas.1519620113 Sites: US-Bar, US-Ced, US-Ho1, US-KFS, US-Kon, US-Me2, US-Me6, US-MMS, US-Mpj, US-NR1, US-PFa, US-Slt, US-SRC, US-SRM, US-Ton, US-UMB, US-Var, US-Vcm, US-Vcp, US-Whs, US-Wjs, US-Wkg
It is necessary to partition eddy covariance measurements of carbon dioxide exchange into its offsetting gross fluxes, canopy photosynthesis, and ecosystem respiration, to understand the biophysical controls on the net fluxes. And independent estimates of canopy photosynthesis (G) and ecosystem respiration (R) are needed to validate …
Journal: Agricultural and Forest Meteorology, Volume 207: 117-126 (2015). DOI: 10.1016/j.agrformet.2015.03.010 Sites: CA-Ca1, CA-Ca2, CA-Ca3, CA-Let, CA-Mer, CA-NS1, CA-NS3, CA-NS5, CA-NS6, CA-NS7, CA-Oas, CA-Obs, CA-Ojp, CA-Qcu, CA-Qfo, CA-SJ2, CA-SJ3, CA-TP4, CA-WP1, US-ARM, US-Aud, US-Bo1, US-Ho1, US-Ho2, US-IB2, US-KS2, US-MMS, US-MOz, US-NC2, US-NR1, US-SO2, US-SO3, US-SO4, US-SP2, US-SP3, US-SRM, US-Ton, US-Tw3, US-UMB, US-Var, US-WBW, US-Wkg, US-Wrc
Journal: Journal Of Geophysical Research: Biogeosciences, Volume 119 (7): 1458-1473 (2014). DOI: 10.1002/2014JG002623 Sites: CA-Ca1, CA-Gro, CA-Let, CA-Oas, CA-Ojp, CA-Qfo, US-ARM, US-Dk3, US-Ha1, US-Ho1, US-IB2, US-Me2, US-MMS, US-MOz, US-Ne1, US-Ne2, US-Ne3, US-NR1, US-PFa, US-Syv, US-Ton, US-UMB, US-Var, US-WCr
The binary nature of Northern California’s ecohydrology, in which water is either abundantly available or scarce, should be reflected in the root architecture of the native blue oak. Our objective was to quantify carbon storage and understand how the form of the root system facilitates ecosystem functioning despite the asynchrony …
Journal: Journal Of Geophysical Research: Biogeosciences, Volume 118 (1): 135-147 (2013). DOI: 10.1029/2012jg002160 Sites: US-Ton
Journal: Agricultural And Forest Meteorology, Volume 171-172: 31-45 (2013). DOI: 10.1016/j.agrformet.2012.11.023 Sites: CA-Ca1, CA-Ca2, CA-Ca3, CA-Gro, CA-Let, CA-Mer, CA-NS1, CA-Oas, CA-Obs, CA-Ojp, CA-Qfo, CA-SJ1, CA-SJ2, CA-SJ3, CA-TP4, CA-WP1, US-ARM, US-Dk3, US-Ha1, US-Ho1, US-IB1, US-Los, US-Me3, US-Me5, US-MMS, US-MOz, US-Ne1, US-Ne2, US-Ne3, US-NR1, US-Shd, US-SO2, US-Syv, US-Ton, US-UMB, US-Var, US-WCr
Most land surface and ecosystem models assume that a vegetated canopy can be abstracted as a turbid medium when such models compute mass, energy, and carbon exchange. However, those models fail to simulate radiation environments in heterogeneous landscapes. This study aims to couple a spatially explicit three-dimensional (3D) shortwave …
Journal: Agricultural And Forest Meteorology, Volume 152: 83-100 (2012). DOI: 10.1016/j.agrformet.2011.09.008 Sites: US-Ton
- Seasonal and inter-annual variability in ecosystem carbon dioxide (CO2) exchange is attributed to numerous climate drivers. However, climate effects on metabolism often override ecological functions. This study seeks insight into which biological and ecological processes influence temporal patterns of ecosystem …
Journal: Functional Ecology, Volume 25 (1): 258-270 (2011). DOI: 10.1111/j.1365-2435.2010.01779.x Sites: US-Ton
Savannas are spatially heterogeneous, open ecosystems, thus efforts to quantify canopy structure with methods developed for homogeneous, closed canopies are prone to failure. We examine the applicability of two direct (litterfall, allometry) and five indirect (LAI-2000, …
Journal: Agricultural And Forest Meteorology, Volume 150 (1): 63-76 (2010). DOI: 10.1016/j.agrformet.2009.08.007 Sites: US-Ton
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). DOI: 10.1007/s10533-009-9381-1 Sites: US-Ton
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). DOI: 10.1016/j.agrformet.2010.01.009 Sites: US-Ton