Das Projekt "Einfluss von Trockenstress auf die Photosyntheseaktivitaet verschiedener Oekotypen der Buche (Fagus sylvatica)" wird vom Umweltbundesamt gefördert und von Universität Karlsruhe, Fakultät für Bio- und Geowissenschaften, Botanisches Institut und Botanischer Garten, Lehrstuhl 2 Pflanzenphysiologie und Pflanzenbiochemie durchgeführt. Ziel des Vorhabens ist es, an Buchen im Conventwald, die Trockenstress ausgesetzt werden, die Photosynthesekapazitaet und deren Stoerung im Zuge der Vegetationsperiode zu erfassen. Dies erfolgt parallel zu anderen Arbeitsgruppen, die den N-Stoffwechsel der Buche und den N-Haushalt sowie die mikrobielle N-Umsetzung im Boden untersuchen. Hierbei werden Photosynthese-relevante, physiologische Parameter vergleichend erfasst, um ein moeglichst vollstaendiges Bild ueber die Stressempfindlichkeit verschiedener Oekotypen der Buche zu erhalten. Botanik II, Karlsruhe wird speziell Nettophotosynthese, Atmung, Transpiration, stomataere Leitfaehigkeit, 'water use efficiency' (WUE), bestimmen. Soweit erforderlich, werden die Chlorophyllfluoreszenzparameter (Fv/Fm, Fv/Fo), und insbesondere die Gehalte an Chlorophyllen bei Sonnen- und Schattenblaettern untersucht. Damit sollen die fuer die Pflanze lebenswichtigen Funktionen der Photosynthese, Atmung und Wasserabgabe bestimmt werden. Neben natuerlicher Variation (Tages- und Jahresgaenge) soll die Stressanpassung der Buchen definiert werden, um Empfehlungen fuer den Anbau bestimmter Buchenoekotypen unter den sich aendernden Umweltbedingungen zu erarbeiten.
Das Projekt "Genetic diversity, ecotype differentiation and population biology of an endangered primeval-forest lichen, Lobardia pulmonaria in a suture zone in the Ural Mountains" wird vom Umweltbundesamt gefördert und von Eidgenössische Forschungsanstalt für Wald, Schnee und Landschaft durchgeführt. Lichen conservation biology is often faced with widely distributed, but strongly fragmented taxa. If in a global Red List assessment such a taxon is treated as one single unit, one large and stable population may result in a low conservation status of the global population, despite the fact that most populations face a strong decline. In case the global population of a taxon is subdivided into evolutionary significant units (ESU), an individual Red List status might be assigned to each ESU. However, the complex life cycles and long generation times make it very difficult to identify ESU for lichens if ecological differentiation is the crucial criterion for their distinction. As an alternative approach to delimit ESU, genetic differentiation of regional populations has been suggested. Recent developments of molecular markers demonstrated considerable levels of regional genetic differentiation among populations within species and during our first Scopes project we found high levels of genetic differentiation within L. pulmonaria between biogeographic regions in Russia. We identified a broad suture zone of two different evolutionary lineages in the Ural Mountains. The western lineage, as identified by ITS sequences is widely distributed in Africa and Western, Northern and Central Europe. The eastern lineage was found so far in Russia East of the Urals and in North America. Concerning the differentiation within the two ITS types it is likely that these genetically differentiated populations of L. pulmonaria developed independently over considerable evolutionary periods rather than became demographically autonomous through recent isolation, e.g. during anthropogenic deforestation. In this project we will sample additional populations along this suture zone, as well as east and west of it to study possible gene flow between the two distinct evolutionary lineages. In order to test if the genetic differentiation found in regional populations parallel ecological adaptation, we had established a provenance clone test during our first Scopes project. We expect that during the coming three years the growth of the transplants will have reached an optimal level, which will then allow to test if survival and growth rate, diaspore production and degree of parasite attack differ between the provenances from the Carpathians, the Ural Mountains, The Komi Republic and Sakhalin. A differentiation between the studied L. pulmonaria population into regional ecotypes would have a significant impact on the conservation status of this species, because its global population could be subdivided into regional ESU.