<?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%">Gratani, L</style></author><author><style face="normal" font="default" size="100%">Bombelli, A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Leaf anatomy, inclination, and gas exchange relationships in evergreen sclerophyllous and drought semideciduous shrub species</style></title><secondary-title><style face="normal" font="default" size="100%">PHOTOSYNTHETICA</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">cistus incanus</style></keyword><keyword><style  face="normal" font="default" size="100%">leaf inclination</style></keyword><keyword><style  face="normal" font="default" size="100%">leaf life-span</style></keyword><keyword><style  face="normal" font="default" size="100%">leaf mass/area ratio</style></keyword><keyword><style  face="normal" font="default" size="100%">leaf thickness</style></keyword><keyword><style  face="normal" font="default" size="100%">net photosynthetic rate</style></keyword><keyword><style  face="normal" font="default" size="100%">phillyrea latifolia</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">transpiration rate</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1999</style></year></dates><publisher><style face="normal" font="default" size="100%">INST EXPERIMENTAL BOTANY, ACAD SCI CZECH REPUBLIC</style></publisher><pub-location><style face="normal" font="default" size="100%">NA KARLOVCE 1A, PRAGUE 6 CS-160 00, CZECH REPUBLIC</style></pub-location><volume><style face="normal" font="default" size="100%">37</style></volume><pages><style face="normal" font="default" size="100%">573-585</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">There are significant differences in leaf life-span among evergreen sclerophyllous species and drought semideciduous species growing in the Mediterranean maquis. Cistus incanus, which has a leaf life-span of four-eight months, was characterised by the highest net photosynthetic rates (PN). while Quercus ilex and Phillyrea latifolia, which maintain their leaves two-three and two-four years, respectively, had a lower PN- The longer leaf life-span of the two evergreen sclerophyllous species may be justified to cover the high production costs of leaf protective structures such as cuticle, hairs, and sclereids: cuticle and hairs screen radiation penetrating into the more sensitive tissues, and sclereids have a light-guiding function. Q. ilex and P. latifolia have the highest leaf mass/area ratio (LMA = 209 g m(-2)) and a mesophyll leaf density (2065 cells per mm(2) of leaf cross section area) about two times higher than C. incanus. In the typical evergreen sclerophyllous species the steepest leaf inclination (alpha = 56 degrees) reduces 42% of radiation absorption, resulting in a reduced physiological stress at leaf level, particularly in summer. C. incanus, because of its low leaf life-span, requires a lower leaf investment in leaf protective structures. It exhibits a drastic reduction of winter leaves just before summer drought, replacing them with smaller folded leaves. The lower leaf inclination (alpha = 44 degrees) and the lower LMA (119 g m(-2)) of C. incanus complement photosynthetic performance. Water use efficiency (WUE) showed the same trend in Q. ilex, P. latifolia, and C. incanus, decreasing 60% from spring to summer, due to the combined effects of decreased CO2 uptake and increased transpirational water loss.</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%">Tenhunen, J D</style></author><author><style face="normal" font="default" size="100%">Lange, O L</style></author><author><style face="normal" font="default" size="100%">Braun, M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Midday Stomatal Closure in Mediterranean Type Sclerophylls Under Simulated Habitat Conditions in an Environmental Chamber II. Effect of the Complex of Leaf Temperature and Air Humidity on Gas Exchange of Arbutus unedo and Quercus ilex</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">midday stomatal closure</style></keyword><keyword><style  face="normal" font="default" size="100%">net photosynthetic rate (voyant)</style></keyword><keyword><style  face="normal" font="default" size="100%">transpiration rate</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1981</style></year></dates><volume><style face="normal" font="default" size="100%">50</style></volume><pages><style face="normal" font="default" size="100%">5-11</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Shrubs of the Mediterranean sclerophyllous species Arbutus unedo and Quercus ilex were studied under simulated habitat conditions in an environmental chamber. Temperature, humidity, and light intensity were altered stepwise to simulate diurnal changes in conditions similar to those measured in an evergreen macchia in Sobreda, Portugal. Leaves were enclosed in cuvettes which reproduced the growth chamber climate and which allowed measurement of gas exchange. Increasing atmo- spheric stress in the form of higher temperature and lower humid- ity on successive days gradually results in midday depression of transpiration rate and net photosynthesis rate of leaves due to midday stomatal closure.</style></abstract></record></records></xml>