<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Infante, J M</style></author><author><style face="normal" font="default" size="100%">Rambal, S</style></author><author><style face="normal" font="default" size="100%">Joffre, R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Modelling transpiration in holm-oak savannah: scaling up from the leaf to the tree scale</style></title><secondary-title><style face="normal" font="default" size="100%">Agricultural and Forest Meteorology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">oak savannas</style></keyword><keyword><style  face="normal" font="default" size="100%">seasonal hysteresis</style></keyword><keyword><style  face="normal" font="default" size="100%">southern Spain</style></keyword><keyword><style  face="normal" font="default" size="100%">Transpiration</style></keyword><keyword><style  face="normal" font="default" size="100%">vapour pressure deficit</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1997</style></year></dates><volume><style face="normal" font="default" size="100%">1923</style></volume><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The transpiration of oak-savannas in southern Spain was modelled by scaling-up from the leaf to the tree during a drought period. Two chlaracteristics of this ecosystem were found to facilitate the modelling procedure. The first was a near-zero decoupling coefficient between the surface and the surrounding bulk air, which simplifies the transpiration formulation. The second was that the surface conductance (g) is mainly related to the vapour pressure deficit of the air (0,). Based on both of these characteristics, the modelling procedure provides a general model of transpiration over the time scale appropriate for a drought period, from days to months. The response of g to 0, was found to follow a negative exponential function, such that beyo’nd a minimum value, g becomes independent of 0,. This implies a feedback control on g by 0,. The consequences of tbis control for transpiration were found at different levels of plant water status. This explains the plants’ adaptation to long dry periods, even though there is also continuous water loss during these periods. Such an adaptation was corroborated by a seasonal hysteresis found in the relationship between transpiration and D, as a function of the plants’ water status</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Joffre, R</style></author><author><style face="normal" font="default" size="100%">Lacaze, B</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Estimating tree density in oak savanna-like lsquo;dehesa’ of southern Spain from SPOT data</style></title><secondary-title><style face="normal" font="default" size="100%">International Journal of Remote Sensing</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Dehesa</style></keyword><keyword><style  face="normal" font="default" size="100%">oak</style></keyword><keyword><style  face="normal" font="default" size="100%">savanna-like</style></keyword><keyword><style  face="normal" font="default" size="100%">SOPT data</style></keyword><keyword><style  face="normal" font="default" size="100%">southern Spain</style></keyword><keyword><style  face="normal" font="default" size="100%">tree density</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1993</style></year></dates><publisher><style face="normal" font="default" size="100%">Taylor &amp; Francis</style></publisher><volume><style face="normal" font="default" size="100%">14</style></volume><pages><style face="normal" font="default" size="100%">685-697</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Abstract The main objective of this study was to establish a method of estimating tree density in savanna-like vegetation systems using the highest spatial resolution available from satellite data (SPOT-1 panchromatic = 10 m resolution) based on the assumption that for sparse trees on a contrasting herbaceous background, spatial filters may provide a direct mapping of tree cover. The study was performed in the ?dehesas? oak-woodland of southern Spain. This particular landscape is characterized by the presence of scattered evergreen oak trees (Quercus ilex and Q. suber) whose density ranges from 0 to 80 even-aged mature trees per hectare which gives the appearance of a savanna-like vegetation. Tree density can be accurately estimated by SPOT-1 panchromatic data after numerical filtering. This method allows the mapping of tree density of the dehesas, a key parameter reflecting the functional vegetation-soil-climate equilibrium which exists for both woody and herbaceous strata.</style></abstract><notes><style face="normal" font="default" size="100%">doi: 10.1080/01431169308904368</style></notes><research-notes><style face="normal" font="default" size="100%">doi: 10.1080/01431169308904368</style></research-notes></record></records></xml>