Untersuchungen zur Auswirkung von Mahonia aquifolium auf die natürliche Verjüngung in Hangwäldern des Unteren Saaletals

Im Rahmen dieser Arbeit wird die Ausbreitung von M. aquifolium auf die natürliche Gehölzverjüngung in Hangwäldern untersucht. Hierzu werden vier Flächen ohne und vier Flächen mit Mahonien-Beständen unter Betrachtung verschiedener Parameter miteinander verglichen. Es findet neben der Vegetationsaufnahme die Kartierung der Gehölzverjüngung auf jeweils vier Probeplots innerhalb dieser Flächen statt. Im Zuge der Auswertung findet eine Analyse der Mittelwerte und Standartabweichungen in Bezug auf die Parameter Artenzahlen, Deckungsgrade sowie Individuenzahlen der Verjüngung und Deckung von M. aquifolium statt. Die Ergebnisanalyse führt zu der Feststellung , dass basierend auf den erhobenen Daten keine eindeutige Aussage bezüglich der Auswirkung von M. aquifolium auf die Gehölzverjüngung getroffen werden kann. Dies ist auf die ausgeprägte Varianz der Kennwerte innerhalb der Varianten bzw. die Flächeninhomogenität zurückzuführen. Es kann im Allgemeinen lediglich eine negative Auswirkung vermutet, diese jedoch wegen der erwähnten Ungleichverteilung der Daten nicht statistisch belegt werden. Vor diesem Hintergrund könnte möglicherweise eine Ausweitung der Untersuchung durch das Hinzuziehen weiterer Probeplots bzw. Untersuchungsflächen zielführend sein.

Neogene floras and palaeoclimatic estimates from various sites of South-West China

Neogene climates and vegetation history of western Yunnan are reconstructed on the basis of known fossil plants using the Coexistence Approach (CA) and Leaf Margin Analysis (LMA). Four Neogene leaf floras from Tengchong, Jianchuan and Eryuan in southwestern China are analyzed by the CA, and the paleoclimatic data of one Miocene carpoflora from Longling and three Pliocene palynofloras from Longling, Yangyi and Eryuan are used for comparison. The Miocene vegetation of the whole of West Yunnan is subtropical evergreen broad-leaved forest, and a similar mean annual precipitation is inferred for Tengchong, Longling and Jianchuan. However, by the Late Pliocene a large difference in vegetation occurred between the two slopes of Gaoligong Mountain, western Yunnan. The region of Tengchong retained a subtropical evergreen broad-leaved forest vegetation, whereas in Yangyi and Eryuan a vertical vegetation zonation had developed, which consists, in ascending order, of humid evergreen broad-leaved, needle and broad-leaved mixed evergreen, and coniferous forests. Distinctively, the Late Pliocene vegetational patterns of West Yunnan were already very similar to those of the present, and the Pliocene mean annual precipitation in Tengchong was markedly higher than that of Yangyi and Eryuan. Considering that the overall vegetation of West Yunnan and the precipitation at Yangyi and Eryuan have undergone no distinct change since the Late Pliocene, we conclude that the Hengduan Mountains on the northern boundary of West Yunnan must have arisen after the Miocene and approached their highest elevation before the Late Pliocene. Furthermore, the fact of the eastern portion of the Tibetan Plateau underwent a slight uplift after the Late Pliocene is also supported.

The late Miocene macroflora of the La Cerdaña Basin, Eastern Pirenees, Spain. Towards a Synthesis

The fossil plant-bearing beds of the Tortonian (late Miocene) intramontane basin of La Cerdanya (Eastern Pyrenees, Catalonia, Spain) have been investigated for more than a century, and 165 species from 12 outcrops have been described in previous publications. The sediments with rich plant fossil assemblages, which correspond to lacustrine diatomitic deposits, contain large numbers of plant remains, mainly leaf compressions and impressions. These assemblages are well preserved, a consequence of the rapid accumulation of plant remains in the sediments of the basin's ancient lake, and the often close proximity of its shores to wetland and upland vegetation. This paper provides a comprehensive taxonomic and nomenclatural review of the historic and new collections of late Miocene macroflora for the La Cerdanya Basin. Examination of the newer materials allowed emendments to be made to the diagnoses ofAbies saportana, Acer pyrenakum,Alnus occidentalis, Quercus hispanka and Tilia vidali provided by REROLLE for the basin at the end of the 19th century. In addition, 24 species of vascular plants are identified for the basin for the first time, including one horsetail, three conifers, 19 arboreal or bushy dicotyledonous angiosperms, and one monocotyledonous angiosperm. Indeed, this is the first time that Cedrela helkonia (UNGER) KNOBLOCH, Decodon sp„ Hedera cf multinervis KOLAKOVSKII, Mahonia cf pseudosimplex KVACEK & WALTHER, Smilax cf. aspera L. vm.fossilis and Ulmus cf. plurinervia UNGER have been recorded anywhere in the Iberian Peninsula. The La Cerdanya Basin plant assemblages of the late Miocene mainly consisted of conifers and deciduous broadleaved taxa of Arctotertiary origin; evergreen Palaeotropical elements were less well represented. This flora is similar to those recorded at coeval sites in northern Greece, northern Italy and central and eastern France. Within the Iberian Peninsula, the late Miocene macroflora reported for the nearby Seu d'Urgell Basin is the most similar.