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Povzetek: 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) Which IAS appear in the research forests? b) What is their frequency and cover percentage? c) Whether individual IAS prosper better in 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 the 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. With the intention to calculate number and cover of IAS some statistical analysis was made. In addition, correlations between the abundances of the most present IAS and cover of upper tree layer were carried out. Results: In total, 15 IAS were recorded in studied FHTs. Some species, like Robinia pseudoacacia, 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 (e.g. Solidago sp.). We found out that the most threatened forests are those with prevailing Salix alba, Alnus glutinosa, Fraxinus angustifolia and Ulmus laevis tree species. Those are the forests of FHT 91E0 which have less dense tree canopies, grow closest to the river and on the wettest sites. We found a statistically significant higher number and cover of IAS in the FHT 91E0 and the lowest number and cover in FHT 91L0. Conclusions: Alluvial forests with Alnus glutinosa and Fraxinus excelsior (FHT 91E0) along the Mura River are most prone to invasion of IAS. The increasing presence of IAS in the study areas seriously affects natural regeneration, stability, and continuity of floodplain forests in all other FHTs in the study area. At the same time the amount of IAS in these forests also depends on management measures and their intensities which accelerate light availability. Some measures and guidelines for managing of these forests with the purpose of reducing IAS impacts are suggested in this study.
Ključne besede: non-native plants, riparian vegetation, habitat types, conservation management, forest management
Objavljeno v DiRROS: 16.04.2018; Ogledov: 2866; Prenosov: 1514
Celotno besedilo (1,03 MB)
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Povzetek: In most mammalian species, body mass is one of the key factors affecting an individual's fitness. It is therefore important to know the causes of its variability. The present paper analyses the influences of habitat structure and other environmental factors on body mass in red deer. The research is based on data sets concerning 3,920 culled red deer from the entire Slovenia, which are geo-referenced within a kilometer spatial accuracy, and on 28 spatially explicit raster layers of population density, habitat structure variables (e.g. topography, land use, forest structure, roads) and other environmental variables (e.g. air temperature, precipitation, supplementary feeding). After controlling for sex and age of the individual and its date of culling, body weight significantly differs between population areas, most likely as a result of genotype differences and genotype impact on the phenotype, and is also negatively dependent upon population density and the percentage of conifers and positively dependent upon annual mean air temperature and forest/meadow edge density. The stated environmental factors probably influence the achieved energy balance and, therefore, the body mass of red deer by conditioning the quantity and quality of food and energy expenditure of deer.
Ključne besede: red deer, body weight, habitat, evironmental factors, population density, forest edge, conifer, temperature, Slovenia
Objavljeno v DiRROS: 12.07.2017; Ogledov: 4477; Prenosov: 1999
Celotno besedilo (713,95 KB)

Povzetek: Leta 1998 je v ponovljenem vseslovenskem popisu aktivnosti rastišč divjega petelina (Tetrao urogallus L.) sodelovalo 473 lovcev in gozdarjev v 1.234 opazovanjih. Od skupno evidentiranih 559 rastišč je aktivnih le še 273 (49 %). Od 495 rastišč (88,6 %) v alpskem prostoru je bilo aktivnih 51 %, od ostalih 64 rastišč v dinarskem prostoru je aktivnih 33 %. Aktivne populacije so prisotne na 74 % površine evidentiranega območja razširjenosti. 80,3 % območja razširjenosti je ohranjenega v alpskem (22 ptic/km2) in 19,7 % v dinarskem prostoru (0,07 ptic/km2) na 4.839 km2 ali 22 % površine Slovenije. Delež aktivnih rastišč v gozdovih na površinah po 200 m višinskih pasovih narašča linearno, od samo še 16 % aktivnih rastišč nad 601 do 800 m nadmorske višine do 70 % nad 1.401 do 1.600 m. Pod 1.000 m je le 11,2 % vseh aktivnih rastišč. Optimum populacijske gostote je nad 1.201 do 1.600 m na 66 % vseh aktivnih rastišč z 0,59 ptic in 0,18 aktivnega rastišča/km2. Po letu 1986 je število aktivnih rastišč upadlo za 199 (42 %), od tega za 41 % v alpskem in 53% v dinarskem prostoru. Število opuščenih rastišč narašča linearno s padanjem po 200 metrskih višinskih pasovih, od 22,9 % nad 1.401 do 1.600 m do 78,9 % nad 601 do 800 m. Najbolj ogrožena so robna območja razširjenosti v predalpskem ter v dinarskem prostoru, najbolj ohranjena so v gorskih gozdovih smreke in bukve.
Ključne besede: divji petelin, Tetrao urogallus (L.), areal razširjenosti, habitat, gozd, gozdnata krajina, spreminjanje gozda
Objavljeno v DiRROS: 12.07.2017; Ogledov: 4626; Prenosov: 1880
Celotno besedilo (3,01 MB)

Ključne besede: divji petelin, Tetrao urogallus (L.), rastišče, habitat, primernost habitatov, alpski gozd, dinarski gozd, gospodarjenje z gozdom, zaraščanje, ohranjanje habitatov, poročilo
Objavljeno v DiRROS: 12.07.2017; Ogledov: 2834; Prenosov: 423

Ključne besede: divji petelin, ekologija živali, rastišče, habitat, Slovenija
Objavljeno v DiRROS: 12.07.2017; Ogledov: 3206; Prenosov: 854
Celotno besedilo (2,72 MB)