Decline of Potentillo albae-Quercetum Libb. 1933 phytocoenoses in Poland

The historical process of the decline of the thermophilous oak forest was studied at 11 selected localities within the whole area of the association in Poland. The comparative analysis of phytosociological data from the periods of 1929–1981 and 1987–1991 has shown the total decline of Potentillo albae-Quercetum at nine localities as well as symptoms of regression at two localities. It has been stated that in Eastern Pomerania and in Greater Poland in the places of Potentillo albae-Quercetum phytocoenoses the communities of Galio-Carpinetum and Calamagrostio-Quercetum have appeared. In the central, north-east, south-east and southern part of the country, the thermophilous oak forest has changed into Tilio-Carpinetum phytocoenoses. The results of the study indicate that the recession of Potentillo albae-Quercetum is taking place in the whole area of the association in Poland. The size of the area is changing, the number of localities is decreasing. The consequence of the thermophilous oak forest decline is the unification and impoverishment of woodland vegetation and flora. These localities of the association which exist up to date are refuges for many interesting helio- and thermophilous species. Their presence to a great extent determines the genetic pool and diversity of Polish flora.Abbreviations Acc accompanying - FB Festuco-Brometea - Fg Fagetalia sylvaticae - MA Molinio-Arrhenatheretea - QF Querco-Fagetea - Qp Quercetalia pubescentis - SN Sedo-Scleranthetea and Nardo-Callunetea - TG Trifolio-Geranietea sanguinei - VP Vaccinio-Piceetea     

Holocene forest development in the central Scandes Mountains, Sweden

Pollen analyses of sediment cores from two small lakes within the boreal forest in the central Scandes Mountains help to elucidate the Holocene forest dynamics of the region. Analyses of pore/pollen grain diameter ratios of Alnus grains indicate the early Holocene presence of Alnus glutinosa in the study area. The results are discussed in conjunction with available pollen records to evaluate the importance of thermophilous trees during the early Holocene and to deduce the regional spread of Picea abies. Corylus avellana, Alnus glutinosa and Ulmus glabra were probably common constituents of the early Holocene forest. Tilia cordata may have occurred there as a rare tree. Pollen stratigraphies from the region do not indicate the occurrence of Quercus robur. The regional spread of Picea abies can be separated into two phases: a mid-Holocene establishment or first expansion of small outpost populations and a late-Holocene population expansion. The mid-Holocene shift in vegetation composition may have been caused by changes in the westerly airflow.     

棒孢拟青霉和丽玛利亚霉鲜红变种——中国2个丝状真菌新记录种

从采自我国山西、辽宁及广西的土样中分离获得了棒孢拟青霉(Paecilomyces clavisporus Hammill)和丽玛利亚霉鲜红变种[Mariannaea elegans(Corda)Samson var.punicea Samson]2个丝状真菌新记录种,并详细描述了这2种菌的形态学特征。     

An investigation of the biodiversity of thermophilic and thermotolerant fungal species in composts using culture-based and molecular techniques

In this study, the biodiversity of thermophilous fungi in two different commercial composts was investigated using culture-based methods, denaturing gradient gel electrophoresis (DGGE) and tag-encoded pyrosequencing. 454 pyrosequencing of the internal transcribed spacer (ITS) region recovered a total of 175 OTUs between the two composts. The Ascomycota was the dominant phylum in both composts (90 % of all sequences recovered) with the thermophilic-rich orders Sordariales and Eurotiales being the most numerous. Molecular studies demonstrated the frequent presence of several thermophilic (Scytalidium thermophilum, Myriococcum thermophilum) and thermotolerant (Pseudallescheria boydii, Corynascus verrucosus and Coprinopsis sp.) fungi in the composts, despite the absence of these species from the culture-based analysis. Conversely, Aspergillus fumigatus and Mycocladus corymbifer, which were the dominant species in cultivation analyses, had very low representation in molecular studies. The results show that the previous picture of the dominant thermophilous fungi in compost communities derived from culture-based analysis has been biased, and that composting environments represent a potentially rich resource of novel fungi.