La fitotoxicitat de l'ozó a Catalunya. Bioindicació i ecofisiologia

摘要: Aquesta tesis es centra en descriure els nivells de la fitotoxicitat lO3 a Catalunya. En un primer bloc vam patrons temporals i espacials daquesta fitotoxicitat, segon estudiar quines son les causes que produeixen des duna perspectiva ecofisiologica. 1.Seguiment zones rurals Catalunya Es van variacions geografiques, estacionals anuals taxa dany plantes tabac (Nicotiana tabacum Bel-W3) seves relacions amb condicions meteorologiques. Tant concentracions dozo com danys foliars ser maxims al final primavera/principis destiu. Les mes altes del contaminant detectar costa, pero majors sensibilitats toxicitat estacions muntanya. dO3 presentaven bones correlacions el foliar. Malgrat aixo observats una amplia varianca resposta escala local, manera nomes 11 % era explicat per lO3. La tant seva capacitat bioindicadors depenia ambientals, principalment daquelles afecten comportament estomatic ara VPD. La integracio categoritzacio dels valors foliar obtinguts arreu territori anys seguiment va mostrar forta relacio (99 varianca) expressades dAOT20. Aixi, regional N. cv. Bel-W3 bon bioindicador dO3.Tenint compte resultats especie, proposem valor d AOT40 (concentracio acumulada sobre llindar 40 ppbv diurnes) 1.28 ppmv·h acumulat periodes quinzenals, partir qual podrien produir-se especies sensibles Catalunya. 2. Respostes ecofisiologiques lO3 De lexposicio Quercus ilex subsp. ilex, Ballota, Olea europaea sylvestris Ceratonia siliqua diferents controlades (OTC) varen observar efectes lecofisiologia daquestes especies. Durant any dexposicio leficiencia fotoquimica maxima, Fv/Fm, decreixer fumigades especialment estressants sistemes mediterranis (hivern estiu). canvi durant si increment d13C dos estudiades, mantenir C. siliqua. Totes estudiades presentar reduccions contingut clorofil·la dexposicio, aquest efecte no any. elevades produir canvis caracteristiques anatomiques morfologiques fulles dalgunes especies, LMA (massa unitat darea especifica) gruix mesofil. disminucions N d15N totes segurament provocat patro retranslocacio lligat acceleracio senescencia. Els mostren gradacio sensibilitat l O3 segons lespecie. dues subespecies Q. major ja que, ambientals N, d15N, clorofil·la, larea foliar, biomassa. Tot aixi, sota fumigacio disminucio 24%, seguida (12-17%) dO. (ns). These thesis is focused in the ozone phytotoxicity levels Catalonia. In first block we have make temporal and spatial description of Catalonia second studied what it below an ecophysiological perspective. 1. Ozone Catalonia The (O3) rural areas (N.E. Spain) biomonitoring capacity tobacco tabacum) cultivars were assessed by determining percentage leaf area injured plants this cultivar exposed from spring to autumn since 1995 1999. The study was conducted simultaneously on nine field sites where ground level concentrations meteorological parameters continuously monitored. Geographical, seasonal annual variations damage rate their links with conditions studied. increased at end beginning summer. Coastal generally presented higher than inland mountain sites. These most sensitive ones toxicity. correlated well injury. However, local scale did not fully account for all observed injury (only 11%). response therefore its depended also different environmental conditions, mainly those linked stomatal behaviour such as VPD. categorisation 10% intervals averaging throughout whole period region, strongly improved (99% variance accounted) relationship expressed AOT20 (accumulated over cut off 20 ppbv). Nicotiana thus very good biomonitor long term scale. Taking into phytotoxical cultivar, propose biweekly (with solar radiation threshold 50 W m-2) species. 2. Ecophysiologycal effects four Mediterranean taxa. Four tree taxa: ballota, siliqua, open top chambers (OTCs) during two years. Three treatments applied: charcoal-filtered air (CF), non-filtered (NF) plus (NF+). photochemical maximal efficiency, decreased NF+ year exposure, especially stressful seasons (winter summer). An increase _13C found three species exposure. This finding only maintained year. Decreases chlorophyll content detected fumigations species, but treatment induced changes anatomical characteristics, (leaf mass area) spongy parenchyma thickness, which some species. A reduction when OTCs, suggesting change retranslocation pattern acceleration senescence, indicated above mentioned biochemical changes. subspecies concentration, chlorophyll, area, biomass occurred ambient concentrations. responsive (24% reduction) treatment, followed O. (ns).