No abstract

Oybak Dçnmez E. 2008. Pollen morphology in Turkish Crataegus (Rosaceae). Pollen morphology of 20 Turkish Crataegus L. taxa (Rosaceae) was studied using light and scanning electron microscopy to assess whether pollen traits are of taxonomic value in this species group. The most frequent aperture type was tricolporate, but nontricolporate pollen grains (trisyncolporate, tetracolporate and inaperturate) were also present in many taxa, and pollen grains of varying aperture types were even found on the same plant. There was considerable variation within and between plants in pollen size (polar axis and equatorial axis ranging from 15 to 65 mm) and in aperture size, but no consistent differences between the taxa examined. Exine patterns varied from a striate-perforate type (the most common one) to rugulate, perforate and microreticulate types. Again, most taxa represented by several specimens in this study had variable patterns. These results imply that pollen traits cannot be used to distinguish Turkish Crataegus taxa or to draw conclusions about their taxonomic affinities.

The sediment of Lake Çubuk in NW Anatolia, which is situated very close to the climate boundary between the dry Central Anatolia and the wet Marmara region, is regarded as a suitable climate archive to test inward and outward movements of this boundary in accordance with past climate variations. Herein, we study the stratigraphic record of the last 2800 years of this landslide-dammed lake at 1030 m elevation, using multi-proxy tools (sedimentology, major and trace element geochemistry, stable isotopes, pollen, diatoms and ostracods) and compare the results with other contemporaneous Anatolian climatic records. Our findings indicate that Lake Çubuk recorded seven distinct climatic periods in the last 2800 years that have been previously revealed elsewhere in Anatolia. The most arid period occurred at the end of the Near-East Aridification Phase at approximately 200 BC when the δ 18 O shifted to very negative values, and the planktonic diatom ratio considerably decreased. The Dark Ages and the late Byzantine periods between AD 670 and 1070 are characterized by more positive δ 18 O values, increasingly higher lake levels and the most extensive arboreal cover of the entire record. The 'Little Ice Age' appeared suddenly, within 40 years, at AD 1350 and is reflected in all of the proxies, including a positive shift in δ 18 O, a sharp decrease in pollen of shrub and herb to the benefit of pine trees and a rapid increase in benthic diatom abundance indicating a lake level shallowing. In many parts of the record, a close match between the stable isotopes and the pollen assemblage zones in the last 2800 years demonstrates that climate rather than human activity was the primary driver of vegetation cover in this mid-altitude mountain of NW Anatolia.

No abstract

The analysis of eight samples of carbonised plant material from the Patnos area (Aǧri), an important site of the Urartian period in eastern Turkey is presented. Bread/macaroni wheat (Triticum aestivum L./T. durum Desf.) and domesticated emmer wheat (Triticum dicoccum Schübl.) are the main crop plants. Hulled barley (Hordeum L.) is less abundantly represented. Pulse seeds, bitter vetch (Vicia ervilia (L.) Willd.), lentil (Lens culinaris Medik.) and Latyhrus L.-type were found in smaller numbers. A few wild seeds were also recorded.

The pollen morphology of numerous collections of taxa in the monocotyledonous families Amaryllidaceae, Ixioliriaceae and Iridaceae (order Asparagales) native to Turkey are presented in this study. Nineteen taxa from five genera of Amaryllidaceae, two taxa from Ixioliriaceae, and ten taxa from three genera of Iridaceae were examined with light and scanning electron microscopy. The pollen morphology is described in detail. In addition, pollen morphological data for Iris L., Crocus L. and Romulea Maratti taken from our previously published accounts are also included in the current report to provide an overall synthesis of the pollen characteristics of the three families in Turkey. The accumulated pollen data are described and discussed, and possible evolutionary trends for the pollen characters are considered.

No abstract

No abstract