<?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%">Correia, O A</style></author><author><style face="normal" font="default" size="100%">Oliveira, G</style></author><author><style face="normal" font="default" size="100%">Martins-Loução, M a</style></author><author><style face="normal" font="default" size="100%">Catarino, F M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effects of bark-stripping on the water relations of Quercus suber L</style></title><secondary-title><style face="normal" font="default" size="100%">Scientia gerundensis</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">bark-stripping</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus suber</style></keyword><keyword><style  face="normal" font="default" size="100%">Transpiration</style></keyword><keyword><style  face="normal" font="default" size="100%">water relations</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1992</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1992///</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">18</style></volume><pages><style face="normal" font="default" size="100%">195 - 204</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Quercus suber is the primary source of industrial cork and can produce cork every 9-10 years. The main objective of this work was to investigate the influence of bark stripping on the stomatal activity and water relations of cork-oak. For this purpose, diurnal changes on transpiration, stomatal conductance and water potencial were measured before and after bark stripping during July and August 1989 and 1990. The stripping on the trees had been done at various intensities. The water loss by the stripped surface was also measured. These results show that severe bark-stripping may lead to a decrease in stomatal conductance and considerable water losses. The stripping stress is not clearly dependent on the stripping coefficients, but rather on the water lost by the trunk which varies from tree to tree probably according to the phloemic tissues composition.</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%">Oliveira, G</style></author><author><style face="normal" font="default" size="100%">Correia, O A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Water relations of crok-oak (Quercus suber L.) under natural conditions</style></title><secondary-title><style face="normal" font="default" size="100%">Plant Ecology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Mediterranean climate</style></keyword><keyword><style  face="normal" font="default" size="100%">montado</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus suber</style></keyword><keyword><style  face="normal" font="default" size="100%">soil-to-leaf hydraulic conductivity</style></keyword><keyword><style  face="normal" font="default" size="100%">Stomatal conductance</style></keyword><keyword><style  face="normal" font="default" size="100%">Transpiration</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1992</style></year></dates><volume><style face="normal" font="default" size="100%">99-100</style></volume><pages><style face="normal" font="default" size="100%">199-208</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Daily and annual courses of leaf transpiration, stomatal conductance and shoot water potential of four Quercus suber individuals were compared in a semi-natural stand in southwest Portugal, from spring 1989 to early summer 1990. The trees investigated showed annual patterns typical of evergreen sclerophyllous species but varied in their range of stomatal operation. This appeared to be related to differences in hydraulic conductiv- ity in the root-to-leaf pathway. Maximum stomatal conductance and transpiration rates occurred from March to June. Water stress was found to be moderate and winter cold stress due to low air and soil temperatures appeared to have an influence on plant water balance through their effects on flow resistances. Abbreviations.&quot; g ..... stomatal conductance; g ....... maximum stomatal conductance, PAR, photosyntheti- cally active radiation; RH, relative humidity of the air; T, leaf transpiration; Ta, air temperature; TL, leaf temperature; T ........ maximum leaf transpiration; AW, air-to-leaf vapor pressure difference; W, shoot water potential; tIJPD, predawn shoot water potential; ttJMIN, minimum shoot water potential.</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%">Oliveira, G</style></author><author><style face="normal" font="default" size="100%">Correia, O A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Water relations of crok-oak (Quercus suber L.) under natural conditions</style></title><secondary-title><style face="normal" font="default" size="100%">Plant Ecology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Mediterranean climate</style></keyword><keyword><style  face="normal" font="default" size="100%">montado</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus suber</style></keyword><keyword><style  face="normal" font="default" size="100%">soil-to-leaf hydraulic conductivity</style></keyword><keyword><style  face="normal" font="default" size="100%">Stomatal conductance</style></keyword><keyword><style  face="normal" font="default" size="100%">Transpiration</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1992</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1992///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.springerlink.com/index/v1675t7354l52260.pdf</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">99-100</style></volume><pages><style face="normal" font="default" size="100%">199 - 208</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Daily and annual courses of leaf transpiration, stomatal conductance and shoot water potential of four Quercus suber individuals were compared in a semi-natural stand in southwest Portugal, from spring 1989 to early summer 1990. The trees investigated showed annual patterns typical of evergreen sclerophyllous species but varied in their range of stomatal operation. This appeared to be related to differences in hydraulic conductiv- ity in the root-to-leaf pathway. Maximum stomatal conductance and transpiration rates occurred from March to June. Water stress was found to be moderate and winter cold stress due to low air and soil temperatures appeared to have an influence on plant water balance through their effects on flow resistances. Abbreviations.&quot; g ..... stomatal conductance; g ....... maximum stomatal conductance, PAR, photosyntheti- cally active radiation; RH, relative humidity of the air; T, leaf transpiration; Ta, air temperature; TL, leaf temperature; T ........ maximum leaf transpiration; AW, air-to-leaf vapor pressure difference; W, shoot water potential; tIJPD, predawn shoot water potential; ttJMIN, minimum shoot water potential.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>3</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Correia, O A</style></author><author><style face="normal" font="default" size="100%">Oliveira, G</style></author><author><style face="normal" font="default" size="100%">Martins-Loução, M a</style></author><author><style face="normal" font="default" size="100%">Catarino, F M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Aspectos fisiológicos do descortiçamento em Querqus suber</style></title><secondary-title><style face="normal" font="default" size="100%">I Congresso Ibérico de Ciências Hortícolas, 18 a 21 de Junho de 1990 em Lisboa</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Descortiçamento</style></keyword><keyword><style  face="normal" font="default" size="100%">Fisiologia vegetal</style></keyword><keyword><style  face="normal" font="default" size="100%">Sobreiro (Quercus Suber L.)</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1990</style></year></dates><pages><style face="normal" font="default" size="100%">469-475</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Quercus suber is the primary source of industrial cork, and can produce cork every 9-10 years. The main objective of the present work was to investigate the influence of the bark stripping of the cork-oak on the stomacal activity and water relations. For this purpose, diurnal variations on transpiration, stomacal conductance and water potencial were studied before and after bark stripping during July and August 1989. The stripping on the trees had been done at various levels. The water loss by the stripping surface was also measured. These preliminary results show that the stress caused by stripping on these trees is different according to the stripping area. The transpiration is immediatly reduced after stripping, under the conditions of these investigations and high stripping coeficients. Sendo o sobreiro uma espécie que proporciona sucessivas tiradas de cortiça, um dos aspectos que importa salientar é o dos exagerados descortiçamentos, que poderão ser um factor de decréscimo de produtividade. Neste trabalho foi estudada a reacção de plantas submetidas a diferentes coeficientes de descortiçamento no que respeita aos parâmetros fisiológicos relacionados com o balanço hídrico e economia de água. Foram efectuados estudos ecofisiológicos em árvores descortiçadas nos meses de Julho 89/Agosto 89, tendo sido estudada a variação diurna da transpiração, condutância estomática e condutividade hidráulica. Foi igualmente determinada a perda de água, por evaporação, através do tronco até à formação de nova periderme. São apresentados resultados preliminares que põem em evidência o stress que o descortiçamento provoca nestas plantas e que é tanto mais grave quanto maior for o coeficiente de descortiçamento aplicado.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>47</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Correia, O A</style></author><author><style face="normal" font="default" size="100%">Oliveira, G</style></author><author><style face="normal" font="default" size="100%">Martins-Loução, M a</style></author><author><style face="normal" font="default" size="100%">Catarino, F M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Aspectos fisiológicos do descortiçamento em Querqus suber</style></title><secondary-title><style face="normal" font="default" size="100%">I Congresso Ibérico de Ciências Hortícolas, 18 a 21 de Junho de 1990 em Lisboa</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Descortiçamento</style></keyword><keyword><style  face="normal" font="default" size="100%">Fisiologia vegetal</style></keyword><keyword><style  face="normal" font="default" size="100%">Sobreiro (Quercus Suber L.)</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1990</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1990</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">469 - 475</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Quercus suber is the primary source of industrial cork, and can produce cork every 9-10 years. The main objective of the present work was to investigate the influence of the bark stripping of the cork-oak on the stomacal activity and water relations. For this purpose, diurnal variations on transpiration, stomacal conductance and water potencial were studied before and after bark stripping during July and August 1989. The stripping on the trees had been done at various levels. The water loss by the stripping surface was also measured. These preliminary results show that the stress caused by stripping on these trees is different according to the stripping area. The transpiration is immediatly reduced after stripping, under the conditions of these investigations and high stripping coeficients. Sendo o sobreiro uma espécie que proporciona sucessivas tiradas de cortiça, um dos aspectos que importa salientar é o dos exagerados descortiçamentos, que poderão ser um factor de decréscimo de produtividade. Neste trabalho foi estudada a reacção de plantas submetidas a diferentes coeficientes de descortiçamento no que respeita aos parâmetros fisiológicos relacionados com o balanço hídrico e economia de água. Foram efectuados estudos ecofisiológicos em árvores descortiçadas nos meses de Julho 89/Agosto 89, tendo sido estudada a variação diurna da transpiração, condutância estomática e condutividade hidráulica. Foi igualmente determinada a perda de água, por evaporação, através do tronco até à formação de nova periderme. São apresentados resultados preliminares que põem em evidência o stress que o descortiçamento provoca nestas plantas e que é tanto mais grave quanto maior for o coeficiente de descortiçamento aplicado.</style></abstract></record></records></xml>