Variations in daytime net carbon and water exchange in a montane shrubland ecosystem in southeast Spain

• DOI: 10.1007/s11099-007-0005-5
• Publication Date: 2007-01-17T02:14:48Z
• Authors: P. Serrano-Ortiz; A. S. Kowalski; F. Domingo; A. Rey; E. Pegoraro; L. Villagarcía; L. Alados-Arboledas
• Keywords: Shrubland; Ecosystem respiration; Photosynthetically active radiation

Carbon and water fluxes in a semiarid shrubland ecosystem located the southeast of Spain (province Almería) were measured continuously over one year using eddy covariance technique. We examined influence environmental variables on daytime (photosynthetically active photons, F P >10 µmol m-2 s-1) gas exchange tested ability an empirical eco-physiological model based to estimate carbon whole year. The showed strong seasonality. During two solstitial periods, summer with warm temperatures (>15 °C) sufficient soil moisture (>10 % vol.) winter mild (>5 high contents vol.), photosynthetic rate was higher than respiration mean CO2 ca. -1.75 -0.60 s-1, respectively. Daytime evapotranspiration averaged 2.20 0.24 mmol By contrast, early autumn dry (<10 also mid-winter near-freezing behaved as net source (mean release 0.60 0.20 respectively). Furthermore, comparison week June 2004 2005 suggests that timing-rather amount-of spring rainfall may be crucial determining growing season exchange. Due strongly limiting other P, applied here failed describe only function could not used most fill gaps data.