Forschungskolloquium PG: ERASMUS+ Visiting Researchers from Iran and Nepal – Mi. 03.06.2026

Physisch-geographisches Kolloquium (PG):

Trees in Iranian Vegetation Regions based on different climate situation (an overview)

Prof. Dr. Kambiz Pourtahmasi (Faculty of Natural Resource, University of Tehran, Iran)

Moderation: Prof. Dr. Achim Bräuning

Iran is located in Middle East and is among Low Forest Cover (forest less than 10 percent of total area) countries. However, it has very diverse climate zones. The temperature during the winter can be in some areas below 0°C and on same time in other areas much above 0°C. The precipitation is varying from 10-50 mm per year up to 1000-1800 mm. Based on this varying climate situation there are five vegetation regions with different trees. The presentation gives an overview about the main biogeographical zones in Iran and their ecological characteristics. The ecological zones include the Hyrcanian or Caspian zone, Irano-Turani zone, Arasbaran zone, Zagros zone, and the Persian Gulf-Omani zone. The most important trees in the Hyrcanian zone are Oak, Beech, Maple, Elm, Buxus, Parrotia, Alnus, Zelkova. In Irano-Turani zone, Juniper, Amygdalus, Pistacia, Haloxylon, Tamarix are the most important ones. In Arasbaran zone, the trees are very similar to the other zones. but with more shrub species and very rich flora. Zagros zone is mainly covered by different Oak species, Pistacia and Amygdalus. In the Persian Gulf-Omani zone, Avicennia, Acacia and Capparis are important floral elements.

Climate change and dendrochronological study in Nepal Himalaya (an overview)

Asst. Prof. Dr. Narayan Prasad Gaire (Patan Multiple Campus, Tribhuvan University Nepal)

Moderation: Prof. Dr. Achim Bräuning

Nepal Himalaya is experiencing rapid climate change with impacts on bio-physical and socio-ecological systems. There is an increase in extremes in both temperature and precipitation along with records of intense and frequent drought events. The impacts of climate change on biological communities are reflected via changes in the phenology, growth and distribution range of the species. Tree-rings, as natural archives, are widely used in diverse environmental change studies. Dendrochronological studies in Nepal started from 1980s and they have covered low to high elevation region of the country.  So far dendrochronological suitability of the more than 30 tree species has been checked and tree-ring chronologies up to 1100 yrs have been developed. Studies found that those trees from high elevation region are more sensitive, responsive to climatic variable and suitable for multi aspect tree-ring research compared to tropical low elevation region. Long term growth analysis of trees found both increasing and decreasing growth trend over time varying with site conditions and species. Treeline dynamics studies have indicated stand densification to treeline shifting in the Nepal Himalaya in response to climate and other environmental changes. Tree growth-climate relationship analysis revealed some broad pattern to site-specific responses. In broad pattern, spring season climate is major growth limiting factor for the growth of the most of the species and sites. Similarly, trees growing in the western part of the Nepal Himalaya are more sensitive to moisture while trees of high elevation region are more influenced by temperature. Growth-climate response is temporally stable to changing. Tree-ring based climate reconstructions have also revealed long-term climate change along with and increase in extreme events. Still gaps exist on some aspects of applications of tree-ring studies in Nepal Himalaya in future like wood anatomy and stable isotopes.

Wann: Mittwoch, 03.06.2026 von 12:30 bis 14:00 Uhr
Wo: Präsenz, Seminarraum 00.210 Tennenlohe, Wetterkreuz 15, 91058 Erlangen.

Vortragsübersicht für das Institutskolloquium im Sommersemester 2026.

******