<?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%">Zavala, MIGUEL a</style></author><author><style face="normal" font="default" size="100%">Espelta, Josep M</style></author><author><style face="normal" font="default" size="100%">Caspersen, John</style></author><author><style face="normal" font="default" size="100%">Retana, Javier</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Interspecific differences in sapling performance with respect to light and aridity gradients in Mediterranean pine–oak forests: implications for species coexistence</style></title><secondary-title><style face="normal" font="default" size="100%">Canadian Journal of Forest Research</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">growth (voyant)</style></keyword><keyword><style  face="normal" font="default" size="100%">light</style></keyword><keyword><style  face="normal" font="default" size="100%">Pinus halepensis</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">sapling mortality</style></keyword><keyword><style  face="normal" font="default" size="100%">Water availability</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2011</style></year></dates><publisher><style face="normal" font="default" size="100%">NRC Research Press</style></publisher><volume><style face="normal" font="default" size="100%">41</style></volume><pages><style face="normal" font="default" size="100%">1432-1444</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The relative abundance of two codominant Mediterranean tree species, shade-tolerant Quercus ilex L. and shade-intolerant Pinus halepensis Mill., is inversely correlated along aridity gradients, but this pattern is not explained by seedling responses to water or light availability, suggesting that subsequent life history stages may explain forest composition. To test this hypothesis, we calibrated statistical models of sapling growth and height–diameter allometry as functions of light availability and climatic variation as well as models of sapling mortality as a function of growth history. Contrary to the expectation of a sun–shade growth trade-off, P. halepensis grew faster than Q. ilex saplings at both low and high light levels. Low precipitation and aridity suppressed sapling growth rates, but no evidence of a shade–drought growth trade-off was found either. Pinus halepensis sapling mortality was strongly growth dependent, exhibiting high mortality rates at low growth, but the mortality of Q. ilex saplings was not. Height–diameter allometric variation was higher in low- than in high-light environments and was more pronounced with respect to changes in light than climatic water. Our results suggest that interspecific differences in sapling mortality and plasticity, rather than growth, may control species distributions at the mesic end of the aridity gradient.</style></abstract><notes><style face="normal" font="default" size="100%">doi: 10.1139/x11-050</style></notes><research-notes><style face="normal" font="default" size="100%">doi: 10.1139/x11-050</style></research-notes></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%">Jiménez, Maria Dolores</style></author><author><style face="normal" font="default" size="100%">Pardos, Marta</style></author><author><style face="normal" font="default" size="100%">Puértolas, Jaime</style></author><author><style face="normal" font="default" size="100%">Kleczkowski, Leszek A</style></author><author><style face="normal" font="default" size="100%">Pardos, Jose Alberto</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Deep shade alters the acclimation response to moderate water stress in Quercus suber L.</style></title><secondary-title><style face="normal" font="default" size="100%">Forestry</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">cork oak seedlings</style></keyword><keyword><style  face="normal" font="default" size="100%">deep shade</style></keyword><keyword><style  face="normal" font="default" size="100%">Drought</style></keyword><keyword><style  face="normal" font="default" size="100%">growth (voyant)</style></keyword><keyword><style  face="normal" font="default" size="100%">light environment</style></keyword><keyword><style  face="normal" font="default" size="100%">Water availability</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2009</style></year></dates><volume><style face="normal" font="default" size="100%">82</style></volume><pages><style face="normal" font="default" size="100%">285-298</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The interactive effects of shade and drought on different morphological and physiological traits were addressed on Quercus suber L. seedlings. In our experiment, limited light treatment (1 per cent) represented the main factor constraining cork oak seedlings growth. Maximal photochemical efficiency (Fv/Fm) with light ≥15 per cent exhibited a midday fall, but under deep shade (1 per cent), Fv/Fm remained constant (&lt;0.8 values) throughout the day. The quantum efficiency of photosystem II (PSII) was lower under moderate drought only in deeply shaded plants. The drought also interacted with light through the increase of the soluble sugar content at 100 per cent light, but not under shade. Under deep shade, soluble sugar content tended to be even lower under moderate drought conditions. The chlorophyll content was not the highest under deep shade as could be expected, while the efficiency of PSII was the lowest under deep shade. We concluded that cork oak can acclimate to moderate shade (15 per cent light), but deep shade impairs some of the physiological responses to cope with low light conditions under moderate drought stress. Plants growing under deep shade were very sensitive to moderate water stress in terms of loss of carbon fixation capacity.</style></abstract><notes><style face="normal" font="default" size="100%">10.1093/forestry/cpp008 </style></notes><research-notes><style face="normal" font="default" size="100%">10.1093/forestry/cpp008 </style></research-notes></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%">Gómez-Aparicio, L.</style></author><author><style face="normal" font="default" size="100%">PÉREZ-RAMOS, I. M.</style></author><author><style face="normal" font="default" size="100%">Mendoza, I.</style></author><author><style face="normal" font="default" size="100%">Matías, L.</style></author><author><style face="normal" font="default" size="100%">Quero, J. L.</style></author><author><style face="normal" font="default" size="100%">Castro, J.</style></author><author><style face="normal" font="default" size="100%">Zamora, R.</style></author><author><style face="normal" font="default" size="100%">MARAÑON, T.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Oak seedling survival and growth along resource gradients in Mediterranean forests: implications for regeneration in current and future environmental scenarios</style></title><secondary-title><style face="normal" font="default" size="100%">Oikos</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">abiotic factors</style></keyword><keyword><style  face="normal" font="default" size="100%">growth (voyant)</style></keyword><keyword><style  face="normal" font="default" size="100%">light</style></keyword><keyword><style  face="normal" font="default" size="100%">Mediterranean forests</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus</style></keyword><keyword><style  face="normal" font="default" size="100%">Regeneration</style></keyword><keyword><style  face="normal" font="default" size="100%">seedling survival</style></keyword><keyword><style  face="normal" font="default" size="100%">soil conditions</style></keyword><keyword><style  face="normal" font="default" size="100%">summer drought</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2008</style></year></dates><volume><style face="normal" font="default" size="100%">117</style></volume><pages><style face="normal" font="default" size="100%">1683-1699</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Understanding seedling performance across resource gradients is crucial for defining the regeneration niche of plant species under current environmental conditions and for predicting potential changes under a global change scenario. A 2-year field experiment was conducted to determine how seedling survival and growth of two evergreen and two deciduous Quercus species vary along gradients of light and soil properties in two Mediterranean forests with contrasting soils and climatic conditions. Half the seedlings were subjected to an irrigation treatment during the first year to quantify the effects on performance of an alteration in the summer drought intensity. Linear and non-linear models were parameterized and compared to identify major resources controlling seedling performance. We found both site-specific and general patterns of regeneration. Strong site-specificity was found in the identity of the best predictors of seedling survival: survival decreased linearly with increasing light (i.e. increasing desiccation risk) in the drier site, whereas it decreased logistically with increasing spring soil water content (i.e. increasing waterlogging risk) in the wetter site. We found strong empirical support for multiple resource limitation at the drier site, the response to light being modulated by the availability of soil resources (water and P). Evidence for regeneration niche partitioning among Quercus species was only found at the wetter site. However, at both sites Quercus species shared the same response to summer drought alleviation through water addition: increased first-year survival but not final survival (i.e. after two years). This suggests that extremely dry summers (i.e. the second summer in the experiment) can cancel out the positive effects of previous wetter summers. Therefore, an increase in the intensity and frequency of summer drought with climate change might cause a double negative impact on Quercus regeneration, due to a general reduction in survival probability and the annulment of the positive effects of (infrequent) ‘wet’ years. Overall, results presented in this study are a major step towards the development of a mechanistic model of Mediterranean forest dynamics that incorporates the idiosyncrasies and generalities of tree regeneration in these systems, and that allow simulation and prediction of the ecological consequences of resource level alterations due to global change.</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%">Metcalf, Woodbridge</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The cork oak tree in California</style></title><secondary-title><style face="normal" font="default" size="100%">Economic Botany</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">acorns</style></keyword><keyword><style  face="normal" font="default" size="100%">California</style></keyword><keyword><style  face="normal" font="default" size="100%">Cork</style></keyword><keyword><style  face="normal" font="default" size="100%">cork oak trees</style></keyword><keyword><style  face="normal" font="default" size="100%">diameter</style></keyword><keyword><style  face="normal" font="default" size="100%">growth (voyant)</style></keyword><keyword><style  face="normal" font="default" size="100%">stripping</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1947</style></year></dates><volume><style face="normal" font="default" size="100%">1</style></volume><pages><style face="normal" font="default" size="100%">26-46</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cork oaks have been planted in Cali- fornia since about 1855, and there are some outstandingly fine specimen trees growing from San Diego to Eureka at elevations below 2,700 feet. There are about 5,000 trees more than ten years old in the state. Cork oak acorns produced in Cali- fornia average 70 per pound, have a high germinative capacity which can be main- tained for twelve months or more by moist cold storage at 38° F., and during most years it should be possible to obtain from five to ten tons of cork oak acorns from California trees. During the past six years about 200,- 000 seedling trees of cork oak have been grown and distributed to land owners under the cooperative cork oak project. Where carefully planted, protected from animal damage and given adequate irri- gation, shade and care, many of these plantations have shown excellent sur- vival and growth. Because of the kind interest and co- operation on the part of owners of cork oak trees, it has been possible to carry on experimental stripping of about 500 cork oaks during the past six years. The stripping season has been found to be from about July 1 to early in October. Most vigorous and full-crowned trees can be stripped easily with the special tools developed and with virtually no damage to the inner bark. It is not advisable to strip trees which are thin crowned or suffering from drought, insects or dis- ease. Removal of cork from ornamental cork oaks changes their appearance but does not seriously check their growth or lessen their ornamental character. The 15 tons of cork has been quite thoroughly tested and found to be well suited for the making of composition cork articles, insulation blocks and other been rapid and satisfactory with trees, usually regaining the diameter before stripping in five years. Indications are that the reproduction cork is of excellent quality. Trees 25 to 30 years of age when stripped have put on a growth of 100 pounds of reproduction cork in five years. The most serious insect enemy of the cork oak in California is the gall wasp which kills many twigs, particularly on trees in dry locations. There is no known control for this pest. If the cooperative distribution of trees can be continued until there are one mil- lion cork oaks growing in California, they will when 30 years old contain an emergency supply of 50,000 tons of cork. This amount may be increased and the quality improved by successive stripping of the trees after they become 20 years of age.</style></abstract></record></records></xml>