ABSTRACT:We documented the current typological and phytosociological characterisation of the ground vegetation as an essential component of biodiversity in 154 Czech forest monitoring plots and to describe its changes during the past 15 years in regard to the deposition and concentration of nitrogen in the soil. Plots were classified as vegetation units in accordance with the UNECE and FAO nomenclature and on the basis of their potential natural vegetation and compared in terms of the occurrence and coverage of the indicative selected nitrophilous species. In all the soil horizons tested statistically significant differences in the C/N ratio were observed between areas with and without the presence of certain selected nitrophilous species (Geranium robertianum, Impatiens parviflora, Sambucus nigra, Urtica dioica). In the areas with the presence of the Geranium robertianum and Urtica dioica species, statistically significantly higher concentrations of nitrogen were recorded in some soil horizons than in those areas with the absence of these species. The findings concerning the influence of nitrogen on nitrophilous herbaceous indicators were compared with the European results obtained in the framework of the ICP Forests international programme and with those of other foreign studies.
Summary The impact of ash dieback caused by Hymenoscyphus fraxineus on 17 provenances of Fraxinus excelsior and one provenance of Fraxinus angustifolia was studied in an extensive field trial established in the Czech Republic prior to the H. fraxineus invasion in 1999. A difference in the level of resistance to ash dieback between the species was found: F. angustifolia was significantly less affected by the disease than F. excelsior. Moreover, particular provenances of F. excelsior showed important differences in the level of resistance to H. fraxineus. A relationship between the impact of ash dieback and altitude was also discovered – the provenances from altitudes above 600 m a.s.l. were less affected by the pathogen than were the provenances from lower areas. No difference in the impact of the disease among provenances of F. excelsior from different ecotopes (ravine, calcareous ravine and alluvial) was found. Substantial among‐tree variability in resistance to H. fraxineus was observed throughout the trial – promising genotypes (with crown defoliation up to 5%) were identified in all 18 tested provenances. In regard to this finding, it appears that the main source of resistance to the pathogen is probably at the individual genotype level in the trial. A secondary but massive attack by Hylesinus fraxini was identified in the trees that had been greatly damaged by ash dieback, and the beetle caused their health to deteriorate significantly. A significant negative effect of the presence of collar necroses caused by H. fraxineus and browse damage was also identified.
ABSTRACT:The preservation and reproduction of gene resources of rare and endemic rowan species were the main aims of this study. Rowan species represent important woody trees from the aspect of forest biodiversity.
This paper deals with the measurement and evaluation of pedunculate and sessile oaks on five provenance trial plots located in the forest regions Západočeská pahorkatina, Jihočeská pánev, Hornomoravský úval, Dolnomoravský úval, Bílé Karpaty and Vizovické vrchy at the age of 20 years. Height and diameter growth were measured and analysed and the quality of tree stems was recorded. Sampled seeds originated from certified stands for seed production located in the Hercynian and Carpathian regions of the Czech Republic. Differences between the two species result from their ecological requirements. A comparison of the two species indicates that pedunculate oak at young age grows better than sessile oak in its typical site conditions. Sessile oak grows relatively worse on the plots situated in floodplain site conditions because it does not tolerate the high levels of groundwater. But the differences were not statistically significant. Significant differences in growth parameters were confirmed within each species among plots and provenances. Large differences in stem shape quality were also recorded already in the early growth phase. In some provenances straight stems were present in up to 56% of the individuals, however, in others straight stems did not appear at all. The total results showed that some pedunculate and sessile oak provenances are more adaptable to site conditions and they suffer lower losses while achieving very good growth.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.