Development of the initial phase after wind throw in the virgin forest remnant Ravna gora

Zaradi vetroloma je leta 1983 v pragozdnem ostanku Ravna gora na Gorjancih na bukovem rastišču (Cardamini savensi-Fagetum) nastala 5,17 ha velika vrzel. Dejstvo, da je izsledkov o pomlajevanju po velikopovršinskih motnjah v pragozdovih malo, nas je vodilo k temu, da smo leta 2000 analizirali stanje indinamiko pomlajevanja vrzeli. Na treh različnih delih vrzeli smo postavili 15 raziskovalnih ploskev z dimenzijami 15 x 15 metrov, znotraj katerih smo analizirali zmes, razrast dreves, sestojno stanje po IUFRO klasifikaciji, pomladek in grobe lesne ostanke. Posebej nas je zanimalo razmerje med bukvijo (Fagus sylvatica L.) in gorskim javorjem (Acer pseudoplatanus L.). Slednjega je največ na sredini vrzeli. Pod sestojem, ki je zapolnil vrzel, je razvit pomladek bukve in javorja, ki je najgostejši na spodnjem (severnem) delu vrzeli. V pomladku prevladuje bukev. Ugotovili smo, da so bile razmere, ki so se izoblikovale po vetrolomu, bistveno drugačne od tipičnega goloseka. Predstavili smo tudi uporabne izsledke za gospodarjenje v gozdovih na podobnihrastiščih.Special attention is given to the gap, which was created in the virgin forest remnant Ravna gora in 1983 by wind throw. The gap in the optimal phase of almost pure beech and on beech site (Cardamini savensi-Fagetum) was 5.17 ha large. In 2000, owing to a lack of investigations in such conditions, we started to research the development patterns of natural regeneration within the gap. 15 sample plots (15 x 15 m) in three different positions within the gap were established. We analysed tree species mixture, architecture, stand structure according to IUFRO classification, advanced regeneration density andcoarse woody debris.The reserach concentrated in particular on the variability of beech (Fagus sylvatica L.) and sycamore (Acer pseudoplatanus L.) mixture in regard to theposition within the gap. It was found out that sycamore was more abundant than beech in the center of the gap. The advanced regeneration density of beech was much higher than sycamore\u27s, and both species were more abundant in the northern part of the gap. The results suggest that the ecological conditions after the wind throw were different when compared to a clear-cut area of similar size. Useful results for managed forests on similar sites are also presented

Occurrence of invasive alien plant species in the floodplain forests along the Mura River in Slovenia

Background and purpose: The objectives of our study were to identify invasive alien plant species (IAS) in the main Natura 2000 forest habitat types (FHT) along the Mura River in Slovenia, and to estimate their abundance and cover. The aim of our study was to find out a) What kinds of IAS appear in the research forests? b) What is their frequency and cover percentage? c) Are individual IAS more attached to some FHT than others? d) What is the correlation between the cover of IAS and the tree layer cover?Materials and methods: We analysed the fidelity of invasive plant species to individual FHT. The studied FHTs along the Mura River were following: 91E0* (Alluvial forests with Alnus glutinosa and Fraxinus excelsior), 91F0 (Riparian mixed forests of Quercus robur, Ulmus laevis and Ulmus minor, Fraxinus excelsior or Fraxinus angustifolia, along the great rivers) and 91L0 (Illyrian oak-hornbeam forests). Two forest areas of about 600 ha were studied in total.Results: 16 IAS were recorded in studied FHTs. Some species, like Robinia pseudacacia, Impatiens glandulifera, I. parviflora, Fallopia japonica (incl. F. x bohemica), Erigeron annuus, Ambrosia artemisiifolia, Amorpha fruticosa, Conyza canadensis and Juncus tenuis occur only in one or two FHTs, while some species can be found in all studied FHTs (like Solidago sp.). We have found that the most threatened forests are those with prevailing Salix alba, Alnus glutinosa, Fraxinus angustifolia and Ulmus laevis, tree species, which grow closest to the river and on the wettest sites.Conclusions: The increasing presence of IAS in the study areas seriously affect natural regeneration, stability, and continuity of floodplain FHTs. Therefore, some measures and guidelines for managing of these forests are suggested in this study.</p

Floodplain forest communities along the Mura River (NE Slovenia)

Ecological gradients along river banks of the Mura River influence forest species composition. On the basis of 58 relevés of floodplain forests along the Mura River, the classification of vegetation plots was performed with the Pc-Ord program. The diagnostic species combination for three clusters revealed after classification was calculated by fidelity measure (phi-coefficient) and presented in an analytic table. Average Ellenberg inidicator values, stream distances and relative elevations of the relevés were passively projected onto PCA to show ecological relationships among them. Correlations of plant functional type and stream distance gradients were calculated with regression analysis. For the main edifiers response curves to the stream distance gradients weremade. The classification of the Mura floodplain forests has revealed three ecologically interpretable vegetation types: Salicetum albae (most humid and nutrient-rich sites), Fraxino-Ulmetum allietosum ursini (ecologically intermediate sites), F.-U. quercetosum robori (the driest and the least nutrient-rich sites). Zonation of vegetation is connected to distance from the closest stream which influences species distribution through ecological gradients of moisture and nutrient. The proportion of therophytes is significantly negatively correlated with the distance from the closest stream and the proportion of neophytes is significantly negatively correlated with distance from the main stream

Prediction of the appearance of tree of heaven in forest communities in western Slovenia

Background and Purpose: Tree of heaven (Ailanthus altissima) is one of the most invasive tree species in Slovenia. Since its invasion into forests is expected, we must raise public awareness and prepare guidelines for forest management in the presence of invasive species. The aim of the research was to predict the potential distribution of tree of heaven, to detect the most endangered forest communities and to discover what characteristics of forest stands make them susceptible.Materials and methods: From databases, literature sources and field observations, we collected all localities in which tree of heaven appears. We assigned these localities geological, geomorphological, soil and climatic data. We then built an ecological model and prepared a map of potential distribution. Based on the modelled future distribution of tree of heaven, we randomly selected and sampled 50 plots in the area in which invasion is expected and beyond this area. We analyzed their morphological and ecological strategies, ecological condition, origin and social behavior spectrum.Results: We found that it has the largest invasive potential in western Slovenia. The model showed that the most susceptible forest communities appear in warm areas with pronounced climatic seasonality. Many differences occur in floristics and plant traits of forest communities in extreme positions, in terms of susceptibility to invasion, but in transitional areas, these differences are not so obvious, only a higher pH of soil and absence of species characteristic of acidophilus communities are an indicator of vulnerability.Conclusion: Susceptibility to invasion by tree of heaven is mainly influenced by macro-climatic conditions; in the transitional zone, communities thriving on shallow, carbonate bedrock are more vulnerable. </p

Nomenclatural remarks to the classifcation of plant communites along post-fire succession

This paper contains the original diagnoses of new syntaxa and typifcations ofexisting names of syntaxa from paper “Classification of plant communities alongpost-fire succession in Pinus brutia stands in southern Antalya (Turkey)” thatwas published in Turkish Journal of Botany. As journal has only on-line versionaccording to ICPN descriptions are not valid. We described syntaxa: Eryngiofalcati-Securigerion securidacae all. nova, Ajugo chiae-Lactucetum serriolae ass.nova, Phlomido grandiflorae-Cistetum salvifolii ass. nova, and Arbuto andrachnes-Quercetum cocciferae ass. nova and selected nomenclatural type for Querco-Phillyreetum mediae Barbero &amp; Quézel 1976

Notes on phytosociology of Juniperus excelsa in Macedonia (southern Balkan Peninsula)

Juniperus excelsa is an East Mediterranean species found also in marginal, sub-mediterranean regions of the southern part of the Balkan Peninsula. It prefers shallow soils in the warmest habitats of the zone of thermophilous deciduous forests. In the past the rank of alliance and the name of Juniperion excelsae-foetidissimae have been suggested for the vegetation dominated by Juniperus excelsa in the Balkan Peninsula. In this paper we present the valid description of the alliance in accordance with the International Code of Phytosociological Nomenclature. The validation of the Juniperion excelsae-foetidissimae required description of a new association - the Querco trojanae-Juniperetum excelsae. The Juniperion excelsae-foetidissimae is classified within the order of Quercetalia pubescentis Klika 1933 (the Quercetea pubescentis Doing-Kraft ex Scamoni et Passarge 1959)