scholarly journals Changes in the Species Composition of Elms (Ulmus spp.) in Poland

Forests ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 1008
Author(s):  
Anna Napierała-Filipiak ◽  
Maciej Filipiak ◽  
Piotr Łakomy

In nearly 600 randomly selected forest stands including elms (Ulmus spp.), we conducted field research to identify them to species level and to find trees showing symptoms of Dutch elm disease (DED). The presented data show that all the 3 native elms (U. glabra, U. laevis, and U. minor) still exist in the whole ranges of their distribution in Poland reported earlier, but their role as forest-forming species has changed. In comparison to published data, the contribution of U. minor has markedly decreased, while an increased contribution was observed in the case of U. laevis, a species which in the past was predominantly located out of woodland and was rarely cultivated. In mountains, where the most frequent is U. glabra, the contribution of elms to forest stands is currently clearly lower than in the lowlands and uplands of Poland. The observed changes most probably result from Dutch elm disease. It cannot be excluded that the changes are at least partly linked with natural correction of forest stand composition modified earlier by human activity (silviculture). In all parts of Poland, trees with symptoms of Dutch elm disease are found, but large-scale decline (of a majority of elm trees) is observed only in about 1.5% of the directly investigated localities.

2010 ◽  
Vol 56 (No. 11) ◽  
pp. 518-530
Author(s):  
S. Vacek ◽  
Z. Vacek ◽  
L. Bílek ◽  
I. Nosková ◽  
O. Schwarz

The research is focused on structure and development of forest stands from 5th to 8th forest vegetation zone in the Krkonoše Mts. The forest stand diversity according to tree species composition and representation, horizontal and vertical structure was evaluated by using following indices: Clark-Evans aggregation index (Clark, Evans 1954), standardised Arten-profil index (Pretsch 2005) and index of complex diversity after Jaehne, Dohrenbusch (1997). Growth model SIBYLA (Fabrika, Ďurský 2005) was used for visualizations and growth predictions of forest stands on particular plots. Based on research results, management recommendations were evaluated.


2015 ◽  
Vol 11 (2) ◽  
pp. 123-138
Author(s):  
Peter Kučera

Abstract According to Kulczyński (1928), a natural Picea abies forest occurs in the mountain range of the Pieniny Mts on the slopes of the mountain Vysoke skalky. Later, various data on the altitudinal range of this stand (and thus on the locality itself) were published: (1) 890 (900) - 950 m, (2) 1000 - 1050 m or (3) around 1000 m. The aim of the field research was to verify published data on the occurrence of a woodland of Upper Mountain Norway spruce (association Polysticho-Piceetum) in the territory of Vysoke skalky. A field study in the area has revealed that most of published data on the occurrence of the Kulczyński’s Picea woodland are incorrect, as its real upper altitudinal limit reaches ± 940 m. The main result is the confirmation of the real existence of a Vaccinium myrtillus-Homogyne alpina-Picea abies phytocoenosis in the territory of Vysoke skalky. However, tree species other than Picea abies (e.g. Fagus sylvatica, Abies alba, Acer pseudoplatanus) could persist in the special habitat of Kulczyński’s ‘Picea woodland’. The natural vegetation of this place was formed by mixed forest stand.


2002 ◽  
Vol 59 (3) ◽  
pp. 451-457 ◽  
Author(s):  
P. F. STEVENS

The state of systematics, for convenience here divided into taxonomy (the delimitation, description and inventory of species) and phylogeny reconstruction, is evaluated. Molecular systematics may seem overemphasized, but the resulting gains made in our understanding of relationships in a relatively short time are very considerable. Although morphological data currently play only a limited role in detecting large-scale phylogenetic pattern, the analysis by Wortley et al. of the role morphology has played in the past is not easily interpreted. At species level, it is unclear what effect molecular techniques will have on our understanding of species limits, but it is likely to be considerable. Although taxonomy is both essential and underfunded, there seems little point in asking for more money until we can justify the limits of the species we describe more clearly and until we have cleared up the impediments that so much slow the practice of taxonomy. Business cannot remain as usual if any of the grand inventory projects we have started are to be finished within a reasonable time, or even to be of much use when they are.


2017 ◽  
Vol 6 (1) ◽  
pp. 79-112 ◽  
Author(s):  
Walter Chambati

This essay examines the changing nature of farm wage labour in the context of the extensive redistributive land reform since 2000. Using field research from two districts in Zimbabwe with contrasting agro-ecology and socio-economic patterns, it shows that agrarian wage labour is not the preserve of large-scale capitalist farms (LSCFs), which it is usually associated with. The new agrarian structure dominated by the peasantry not only employs an expanded base of unpaid family labourers, but also employs ‘informal’ wage labour whose character and conditions of employment are qualitatively different from the full and part-time labour of the past. Yet, there is continuation of the super-exploitation of agrarian wage labourers that is reflected by the payment of poor wages and differing degrees of the institution of the residential labour tenancy in both the old and new farm compounds. Landlessness and/or land shortage continues to be a key characteristic of farm wage labourers as in the past suggesting the persistence of the labour reserve dynamic.


2014 ◽  
Vol 75 (1) ◽  
pp. 13-23 ◽  
Author(s):  
Andrzej Jaworski ◽  
Maciej Pach

Abstract The aim of this research was to find out what changes occurred between 1999-2009 in Oszast reserve in the volume, species composition and diameter at breast height (dbh) distribution of the forest stand, and the number and height of regeneration. The objective was to determine what would be condition of these managed lower montane multispecies forest stands (Swiss irregular shelterwood method or selection cuttings) and what role spruce would play in them if they have not been replaced by spruce monocultures. The research was conducted on three permanent circular sample plots (s.p.), each had size of 1/3 ha. Over 10 years, standing volume of the forest stand increased on s.p. 1 (from around 562 m3/ha to 649 m3/ha) and s.p. 3. (from 653 m3/ha to 660 m3/ha), while decreased on s.p. 2. (from 421 m3/ha to 378 m3/ha). The species composition, defined on the basis of volume share (averaged for the three s.p. jointly), did not undergo consistent changes. However, the relative dominance of beech over spruce was determined based on tree numbers. The average spruce mortality (averaged from three s.p.) did not exceed 10% and was slightly higher than that of beech (6%), and lower than fir mortality (15%). Nevertheless, spruce did not show any symptoms of dieback. The reasons behind its mortality were fallen trees and windbreaks. In regeneration, on the whole, beech or sycamore predominated, and the proportion of spruce and fir was small. In the future spruce and fir may even decrease further by competitive ability of dynamically regenerating beech. Abandonment of forest management to promote greater diversity of species, may favour the formation of beech monocultures, or forest stands dominated by beech, everywhere that beech is already present or will be introduced. The maintenance of stable, multispecies forest stands, with co-dominant fir, beech and spruce of native origin, requires natural or artificial regeneration of spruce and fir, manipulated to restore fir up to about 30%, and reduce spruce down to about 40%. This would be possible through the use of the Swiss irregular shelterwood method and selection system, and by continuous tending of regeneration


2020 ◽  
Vol 4 (4) ◽  
pp. 365-381
Author(s):  
Ny Anjara Fifi Ravelomanantsoa ◽  
Sarah Guth ◽  
Angelo Andrianiaina ◽  
Santino Andry ◽  
Anecia Gentles ◽  
...  

Seven zoonoses — human infections of animal origin — have emerged from the Coronaviridae family in the past century, including three viruses responsible for significant human mortality (SARS-CoV, MERS-CoV, and SARS-CoV-2) in the past twenty years alone. These three viruses, in addition to two older CoV zoonoses (HCoV-229E and HCoV-NL63) are believed to be originally derived from wild bat reservoir species. We review the molecular biology of the bat-derived Alpha- and Betacoronavirus genera, highlighting features that contribute to their potential for cross-species emergence, including the use of well-conserved mammalian host cell machinery for cell entry and a unique capacity for adaptation to novel host environments after host switching. The adaptive capacity of coronaviruses largely results from their large genomes, which reduce the risk of deleterious mutational errors and facilitate range-expanding recombination events by offering heightened redundancy in essential genetic material. Large CoV genomes are made possible by the unique proofreading capacity encoded for their RNA-dependent polymerase. We find that bat-borne SARS-related coronaviruses in the subgenus Sarbecovirus, the source clade for SARS-CoV and SARS-CoV-2, present a particularly poignant pandemic threat, due to the extraordinary viral genetic diversity represented among several sympatric species of their horseshoe bat hosts. To date, Sarbecovirus surveillance has been almost entirely restricted to China. More vigorous field research efforts tracking the circulation of Sarbecoviruses specifically and Betacoronaviruses more generally is needed across a broader global range if we are to avoid future repeats of the COVID-19 pandemic.


Metahumaniora ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 54
Author(s):  
Erlina Zulkifli Mahmud ◽  
Taufik Ampera ◽  
Yuyu Yohana Risagarniwa ◽  
Inu Isnaeni Sidiq

Kedudukan dan fungsi bahasa sebagai alat komunikasi manusia mencakup seluruh bidang kehidupan termasuk ilmu pengetahuan antara lain terkait sejarah peradaban manusia; bagaimana manusia mempertahankan hidupnya, bagaimana manusia memperlakukan alam, bagaimana alam menyediakan segala kebutuhan manusia. Apa yang dilakukan manusia saat ini, saat lampau, dan apa yang dilakukan manusia jauh di masa prasejarah, bagaimana kondisi alam di masa-masa tersebut, apa perubahan dan perkembangannya, dapat didokumentasikan melalui bahasa, divisualisasikan kembali, lalu dipajang sebagai salah satu upaya konversai dan preservasi dalam satu institusi yang disebut museum. Penelitian ini membahas kedudukan dan fungsi bahasa dalam permuseuman. Bagaimana kedudukan dan fungsi bahasa dalam permuseuman baik dalam informasi yang disampaikan oleh pemandu wisata museumnya maupun yang terpajang menyertai benda-benda dan gambar-gambar merupakan tujuan dari penelitian ini. Metode penelitian yang digunakan adalah gabungan antara metode lapangan dan metode literatur. Hasil penelitian menunjukkan bahwa secara umum kedudukan bahasa Indonesia berada pada urutan pertama setelah Bahasa Inggris dan keberadaan kedua bahasa dalam permuseuman ini melibatkan dua fungsi utama bahasa, yakni fungsi komunikatif dan fungsi informatif.The existence and function of language  as a medium of communication covers all fields of human life including knowledge, one of them is the history of human civilization; how humans survived, how human utilized nature for their lives, and how nature provides all the necessities for humans. What humans have been doing now, what they have done in the past and far before that in the pre-history time, how the conditions of the nature at those times were and what changes as well as progresses occurred are documented using language, then re-visualized,  displayed as one of conservation and preservation acts in an institution called museum. This research discusess the existence and function of language in museums. How important the existence of a language in museums and what language functions used in museums both in informations given by the museum guides and on the displays accompanying objects and pictures are the aims of this research. The methods used are the combination between field research and library research. The results show that generally the existence of Indonesian language plays more important role than English and both languages have two main functions; communicative function and informative function.     


2011 ◽  
Vol 72 (4) ◽  
pp. 339-356 ◽  
Author(s):  
Andrzej Jaworski ◽  
Dorota Jakubowska

Dynamika zmian budowy, struktury i składu gatunkowego drzewostanów o charakterze pierwotnym na wybranych powierzchniach w Pienińskim Parku Narodowym


2020 ◽  
Author(s):  
Lungwani Muungo

The purpose of this review is to evaluate progress inmolecular epidemiology over the past 24 years in canceretiology and prevention to draw lessons for futureresearch incorporating the new generation of biomarkers.Molecular epidemiology was introduced inthe study of cancer in the early 1980s, with theexpectation that it would help overcome some majorlimitations of epidemiology and facilitate cancerprevention. The expectation was that biomarkerswould improve exposure assessment, document earlychanges preceding disease, and identify subgroupsin the population with greater susceptibility to cancer,thereby increasing the ability of epidemiologic studiesto identify causes and elucidate mechanisms incarcinogenesis. The first generation of biomarkers hasindeed contributed to our understanding of riskandsusceptibility related largely to genotoxic carcinogens.Consequently, interventions and policy changes havebeen mounted to reduce riskfrom several importantenvironmental carcinogens. Several new and promisingbiomarkers are now becoming available for epidemiologicstudies, thanks to the development of highthroughputtechnologies and theoretical advances inbiology. These include toxicogenomics, alterations ingene methylation and gene expression, proteomics, andmetabonomics, which allow large-scale studies, includingdiscovery-oriented as well as hypothesis-testinginvestigations. However, most of these newer biomarkershave not been adequately validated, and theirrole in the causal paradigm is not clear. There is a needfor their systematic validation using principles andcriteria established over the past several decades inmolecular cancer epidemiology.


2004 ◽  
Vol 2 (1) ◽  
pp. 49-63 ◽  
Author(s):  
Carlos Magnavita ◽  
Norbert Schleifer

In the last decades, geophysical methods such as magnetic survey have become a common technique for prospecting archaeological sites. At sub-Saharan archaeological sites, however, magnetic survey and correlated techniques never came into broad use and there are no signs for an immediate change of this situation. This paper examines the magnetic survey undertaken on the Nigerian site of Zilum, a settlement of the Gajiganna Culture (ca 1800-400 BC) located in the Chad Basin and dated to ca 600-400 BC. By means of the present case study, we demonstrate the significance of this particular type of investigation in yielding complementary data for understanding the character of prehistoric settlements. In conclusion, we point out that geophysical methods should play a more important role in modern archaeological field research, as they furnish a class of documentation not achievable by traditional survey and excavation methods, thus creating new perspectives for interpreting the past of African societies.


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