<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pataki, D. E.</style></author><author><style face="normal" font="default" size="100%">Xu, T.</style></author><author><style face="normal" font="default" size="100%">Luo, Y. Q.</style></author><author><style face="normal" font="default" size="100%">Ehleringer, J. R.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Inferring biogenic and anthropogenic carbon dioxide sources across an urban to rural gradient</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">atmospheric co2</style></keyword><keyword><style  face="normal" font="default" size="100%">boreal forest ecosystems</style></keyword><keyword><style  face="normal" font="default" size="100%">carbon isotopes</style></keyword><keyword><style  face="normal" font="default" size="100%">co2</style></keyword><keyword><style  face="normal" font="default" size="100%">fossil</style></keyword><keyword><style  face="normal" font="default" size="100%">fuel emissions</style></keyword><keyword><style  face="normal" font="default" size="100%">isotope composition</style></keyword><keyword><style  face="normal" font="default" size="100%">leaf water</style></keyword><keyword><style  face="normal" font="default" size="100%">metropolitan-area</style></keyword><keyword><style  face="normal" font="default" size="100%">nonsteady state</style></keyword><keyword><style  face="normal" font="default" size="100%">oxygen isotopes</style></keyword><keyword><style  face="normal" font="default" size="100%">respiration</style></keyword><keyword><style  face="normal" font="default" size="100%">respired</style></keyword><keyword><style  face="normal" font="default" size="100%">stable-isotope</style></keyword><keyword><style  face="normal" font="default" size="100%">stomatal conductance</style></keyword><keyword><style  face="normal" font="default" size="100%">urban ecology</style></keyword><keyword><style  face="normal" font="default" size="100%">water-vapor</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">05/2007</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">pub/691</style></url></web-urls></urls><number><style face="normal" font="default" size="100%">2</style></number><volume><style face="normal" font="default" size="100%">152</style></volume><pages><style face="normal" font="default" size="100%">307-322</style></pages><isbn><style face="normal" font="default" size="100%">0029-8549</style></isbn><language><style face="normal" font="default" size="100%">English</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;We continuously monitored CO2 concentrations at three locations along an urban-to-rural gradient in the Salt Lake Valley, Utah from 2004 to 2006. The results showed a range of CO2 concentrations from daily averages exceeding 500 p.p.m. at the city center to much lower concentrations in a non-urbanized, rural region of the valley. The highest values were measured in the wintertime and under stable atmospheric conditions. At all three sites, we utilized weekly measurements of the C and O isotope composition of CO2 for a 1-year period to evaluate the CO2 sources underlying spatial and temporal variability in CO2 concentrations. The results of an inverse analysis of CO2 sources and the O isotope composition of ecosystem respiration (delta O-18(R)) showed large contributions (&amp;gt; 50%) of natural gas combustion to atmospheric CO2 in the wintertime, particularly at the city center, and large contributions (&amp;gt; 60%) of biogenic respiration to atmospheric CO2 during the growing season, particularly at the rural site. delta O-18(R) was most enriched at the rural site and more isotopically depleted at the urban sites due to the effects of irrigation on ecosystem water pools at the urban sites. The results also suggested differences in the role of leaf versus soil respiration between the two urban sites, with seasonal variation in the contribution of leaf respiration at a residential site and relatively constant contributions of leaf respiration at the city center. These results illustrate that spatial and temporal patterns of urban CO2 concentrations and isotopic composition can be used to infer patterns of energy use by urban residents as well as plant and soil processes in urban areas.&lt;/p&gt;</style></abstract><work-type><style face="normal" font="default" size="100%">Article</style></work-type><accession-num><style face="normal" font="default" size="100%">ISI:000246276200013</style></accession-num><notes><style face="normal" font="default" size="100%">&lt;p&gt;ISI Document Delivery No.: 165AMTimes Cited: 12Cited Reference Count: 52Cited References:      *NOAA CMDL, 2005, GLOB CO2 COOP ATM DA     BARBOUR MM, 2005, FUNCT PLANT BIOL, V32, P1107, DOI 10.1071/FP05118     BOWLING DR, 2002, OECOLOGIA, V131, P113     BOWLING DR, 2003, GLOBAL BIOGEOCHEM CY, V17     BUSH SE, 2007, IN PRESS APPL GEOCHE     CERNUSAK LA, 2002, PLANT CELL ENVIRON, V25, P898     CERNUSAK LA, 2004, PLANT PHYSIOL, V136, P3350, DOI 10.1104/pp.104.040758     CERNUSAK LA, 2005, TREE PHYSIOL, V25, P129     CLARKTHORNE ST, 2003, APPL GEOCHEM, V18, P75     CRAIG H, 1965, STABLE ISOTOPES OCEA, P9     DAY TA, 2002, AGR FOREST METEOROL, V110, P229     EWERS BE, 2000, TREE PHYSIOL, V20, P579     FARQUHAR GD, 1993, NATURE, V363, P439     FARQUHAR GD, 1993, STABLE ISOTOPES PLAN, P47     FARQUHAR GD, 2003, PLANT CELL ENVIRON, V26, P1579     FARQUHAR GD, 2005, FUNCT PLANT BIOL, V32, P293, DOI 10.1071/FP04232     FLANAGAN LB, 1991, PLANT PHYSIOL, V96, P588     FLANAGAN LB, 1996, GLOBAL BIOGEOCHEM CY, V10, P629     FLANAGAN LB, 1997, GLOBAL BIOGEOCHEM CY, V11, P83     FLORKOWSKI T, 1998, ISOTOPE TECHNIQUES S, P37     GEHRE M, 2004, RAPID COMMUN MASS SP, V18, P2650, DOI 10.1002/rcm.1672     GELFAND AE, 1990, J AM STAT ASSOC, V85, P398     GELMAN A, 1992, STAT SCI, V7, P457     GEMAN S, 1984, IEEE T PATTERN ANAL, V6, P721     GILL J, 2002, BAYESIAN METHODS SOC     GILLON J, 2001, SCIENCE, V291, P2584     HARWOOD KG, 1999, OECOLOGIA, V119, P109     HASTINGS WK, 1970, BIOMETRIKA, V57, P97     IDSO CD, 1998, PHYS GEOGR, V19, P95     IDSO CD, 2001, ATMOS ENVIRON, V35, P995     KEELING CD, 1958, GEOCHIM COSMOCHIM AC, V13, P322     KEELING CD, 1961, GEOCHIM COSMOCHIM AC, V24, P277     KOERNER B, 2002, ENVIRON POLLUT S1, V116, S45     LAI C, 2006, J GEOPHYS RES, V111     LAI CT, 2006, PLANT CELL ENVIRON, V29, P77     LEONARD T, 1999, BAYESIAN METHODS ANA     MAJOUBE M, 1971, J CHIM PHYS PCB, V58, P1423     MILLER JB, 1999, GLOBAL BIOGEOCHEM CY, V13, P761     MORTAZAVI B, 2002, GLOBAL BIOGEOCHEM CY, V16     PATAKI DE, 2003, GLOBAL BIOGEOCHEM CY, V17, ARTN 1022     PATAKI DE, 2003, J GEOPHYS RES-ATMOS, V108, ARTN 4735     PATAKI DE, 2005, J GEOPHYS RES, V110     PATAKI DE, 2005, STABLE ISOTOPES BIOS, P199     PATAKI DE, 2006, GEOPHYS RES LETT, V33, ARTN L03813     PATAKI DE, 2006, GLOBAL CHANGE BIOL, V12, P1     RILEY WJ, 2003, GLOBAL CHANGE BIOL, V9, P1567, DOI     10.1046/j.1529-8817.2003.00680.x     SCHAUER AJ, 2003, AGR FOREST METEOROL, V118, P113, DOI     10.1016/S0168-1923(03)00065-0     SCHAUER AJ, 2005, RAPID COMMUN MASS SP, V19, P359, DOI 10.1002/rcm.1792     STERNBERG LD, 1998, TELLUS B, V50, P366     TARANTOLA A, 2005, INVERSE PROBLEM THEO     WEST AG, 2006, RAPID COMMUN MASS SP, V20, P1317, DOI 10.1002/rcm.2456     XU T, 2006, GLOBAL BIOGEOCHEM CY, V20Pataki, D. E. Xu, T. Luo, Y. Q. Ehleringer, J. R.SpringerNew york&lt;/p&gt;</style></notes><auth-address><style face="normal" font="default" size="100%">&lt;p&gt;Univ Calif Irvine, Dept Earth Syst Sci, Irvine, CA 92697 USA. Univ Calif Irvine, Dept Ecol &amp;amp; Evolutionary Biol, Irvine, CA 92697 USA. Univ Oklahoma, Dept Bot &amp;amp; Microbiol, Norman, OK 73019 USA. Univ Utah, Dept Biol, Salt Lake City, UT 84112 USA.Pataki, DE, Univ Calif Irvine, Dept Earth Syst Sci, Irvine, CA 92697 USA.dpataki@uci.edu&lt;/p&gt;</style></auth-address></record></records></xml>