MAIN FOCUSES OF ENGLISH PAPERS OF ANNALS (PAAAE) DURING THE LAST TEN YEARS

The aim of the research is to analyze English language scientific articles that have been published in the scientific journal entitled Annals PAAAE from 2009 to 2018 by using tools of text mining and text analysis, measuring how the frequency of key terms has changed, and to conclude the probable change of research focus of authors based on it. The subjects of the research are 393 English language articles that have been issued in the volumes of Annals PAAAE (Polish title is Roczniki Naukowe SERiA) from 2009 to 2018 (from Vol. 11 to Vol. 20), which are ready to download in pdf format on the website of the publishing house. Text mining and text analysis were conducted using own self-adapted routines of samples written in the R language programme. At the hierarchic cluster analysis, the Ward D method was used, and the association of frequency of terms was measured using Pearson’s correlation. It was found that the weight of research concerning the context of the product-production-market has increased, but there was low usage of the term “competitiveness”. What was of key significance was that in the case of clustering articles by author nationality, the role of the origin of the author has decreased as a determinant factor, which could suggest the uniformity of terminology as well as similarity of research topics and the researcher’s interests, which can initialize cooperation and common research. The growth of the number of articles elaborated on by international teams is also a projection of this tendency.

Site patterns of natural regeneration following clear-cutting in northwestern Quebec

Pre- and post-harvest regeneration levels were compared for Abiesbalsamea (L.) Mill. –Betulapapyrifera Marsh. –Picea spp. forests in an area of the southern clay belt of northwestern Quebec. Results revealed abundant advance softwood regeneration (mean = 65 000 stems/ha), almost entirely of Abies prior to harvest. The survey following mechanical and manual whole-tree harvesting suggested a 92% reduction of softwood regeneration and a shift from softwood to a mixed or hardwood-shrub dominated regeneration. Ninety percent of softwood seedlings collected after harvest were pre-established. Destruction of advance regeneration was generally greater on fine-textured soils. Hierarchic cluster analysis of ecological types based on softwood, hardwood, and shrub tree regeneration data as variables, revealed nine groups that could serve as a basis for operational silvicultural decision making. In general, Salix spp. and Alnusrugosa (Du Roi) Spreng. are the major competitors on poorly drained sites; Betula sp., Acerspicatum Lam., and Prunuspensylvanica L.f. dominate on thin organic deposits and coarse deposits, whereas Populustremuloides Michx. and Acerspicatum dominate on fine-textured deposits. These findings suggest that a good understanding of physical site factors can provide useful information for harvesting and silvicultural planning.