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Elsevier Calatayud, V.; García Breijo, FJ.; Cervero, J.; Reig Armiñana, J.; Mª JOSÉ SANZ SÁNCHEZ (2011). Physiological,anatomical and biomass partitioning responses to ozone in the Mediterranean endemic plant Lamottea dianae. Ecotoxicology and Environmental Safety. 74(5):a b s t r a c t Ozone effects on the perennial forb Lamottea dianae were studied in an open-top chamber experiment.Ozone was found to induce reductions in CO 2 assimilation and water use efficiency in the leaves of this species. These reductions were mainly related to a decline in the in vivo CO 2 fixation capacity of Rubisco (V c,max ), rather than to stomatal limitations or photoinhibitory damage (F v :F m ). In addition to chloroplast degeneration, other observed effects were callose accumulation, formation of pectinaceous wart-like cell wall exudates and phloem alterations. Moreover, ozone exposure significantly reduced root dry biomass. The possible relevance of these adverse effects for Mediterranean forbs is commented. These results show that endemic plants can be very sensitive to ozone, suggesting that risks associated with this pollutant should be taken into account for conservation purposes.

The creation of a quality DTM is essential for representing and analyzing the Earth in a digital form. The continuous improvements in the acquisition and the potential of airborne LiDAR data is increasing the range of applications of this technique to the study of the Earth surface. The aim of this study was to determine the optimal parameters for calculating a DTM by using an iterative algorithm to select minimum elevations from LiDAR data in a steep mountain area with shrub vegetation. The parameters were: input data type, analysis window size, and height thresholds. The effects of slope, point density, and vegetation on DTM accuracy were also analyzed. The results showed that the lowest root mean square error (RMSE) was obtained with an analysis window size of 10 m, 5 m, and 2.5 m, rasterized data as input data, and height thresholds equal to or greater than 1.5 m. These parameters showed a RMSE of 0.19 m. When terrain slope varied from 0-10% to 50-60%, the RMSE increased by 0.11 m. The RMSE decreased by 0.06 m when point density was increased from 4 to 8 points/m2, and increased by 0.05 m in dense vegetation areas.

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