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U vegetacijskom razdoblju 2010. godine proveli smo detaljna istraživanja prašume Smrčeve doline na sjevernom Velebitu. Prašumski kompleks obuhvaća oko 488 ha, dio je Nacionalnoga parka »Sjeverni Velebit« i do sada nije znanstveno istraživan. Velik dio prašume zauzimaju sastojine obične smreke rasprostranjene u dvjema šumskim zajednicama: smrekova šuma s obrubljenim gladcem (Laserpitio krapfii-Piceetum abietis Vukelić i dr. 2010) i smrekova šuma s alpskom pljuskavicom (Hyperico grisebachii-Piceetum abietis /Bertović 1975/ Vukelić i dr. 2010).Na gornjim i srednjim padinama rasprostranjena je pretplaninska bukova šuma sa žabljakom (Ranunculo platanifoliae-Fagetum Marinček i dr. 1993). Sva tri vegetacijska tipa fitocenološki su istražena metodom ciriško-monpelješke fitocenološke škole, a snimci smrekovih sastojina prikazani su u analitičkoj tablici 1 s potrebnim općim podacima. Za kvantificiranje strukturnih parametara sastojina na pokusnim plohama svim su stablima iznad 1 cmprsnoga promjera izmjereni opseg (cm), visina (m) te je određen životni status prema metodologiji Masera i dr. (1979). Ustanovljena je količina i stupanj raspadanja mrtvoga dubećega i ležećega drveta i na temelju utvrđenih parametara i odgovarajućih kriterija zaključujemo da smrekove sastojine istraživanoga područja pripadaju kategoriji primarne prašume., Detailed research into the virgin forest of Smrčeve Doline, situated in Northern VelebitNational Park, was undertaken in the vegetation period of 2010 (Fig. 1). The virgin forest covers an area of 488 ha, of which spruce forests account for 300 ha, beech forests for 125 ha, while the rest is without any forest vegetation. The altitude ranges between 1,279 m and 1,607 m. The virgin forest mainly extends in the north-south direction. Over half of the spruce stands are distributed in sinkholes, as well as on northern and northwestern slopes ascending towards the tops. In the geomorphological sense, this is an exceptionally richly developed Dinaric karst relief, where the parent material is made of limestone breccias and limestone-dolomite blocks, which often resurface. The soil is organogenic and organomineral calcomelanosol in a mosaic with calcocambisol. The average annual temperature is 3.5 °C and the amount of the average annual precipitation is 1,898mm(meteorological stationVučjak, 1954mabove sea level, period 1961–1990, data of the DHMZ). Phytocoenological research based on the standard Central European method of the Zürich-Montpellier School has shown that stands of Norway spruce are distributed in two forest communities (Table 1): spruce forest with Laserpitium krapfii (Laserpitio krapfii-Piceetum abietisVukelić, Alegro et Šegota 2010) and spruce forest with Hypericum richerii grisebachii (Hyperico grisebachii-Piceetum abietis /Bertović 1975/ Vukelić, Alegro, Šegota et Šapić 2010). The floral composition with their differences justifies their classification into independent associations in relation to other sub-alpine phytocoenoses of the Dinaric region. Compared with them, spruce forests of the sub-alpine belt of northern Velebit are differentiated by the presence and the higher cover of species Campanula velebitica, Melampyrum velebiticum, Hypericum richeri grisebachii, Laserpitium krapfii, Valerianamontana, Euphorbia carniolica, Geranium sylvaticum,Adenostyl

Vodna erozija tla jedan je od najrazornijih procesa degradacije zemljišta. U gospodarenju šumskim zemljištemmoguća opasnost od erozije uvelike se povećava s povećanjem aridnosti klime.Vodnoj eroziji osobito pogoduju slabo vodopropusni supstrati i tlo koje iz njih nastaje, kao što je fliš. Flišna erodirana zemljišta dosta su rasprostranjena u Istri, gdje smo i proveli ovo istraživanje. Na poligonu za istraživanje erozije Abrami (kod Buzeta) na 6 pokusnih ploha istražili smo svojstva tla i tijekom 3 godine (2005., 2006. i 2007.) mjerili količinu oborine i produkciju erozijskoga nanosa. Na dvjema plohama prije 50 godina provedena je biološko-tehnička sanacija erozije, na jednoj su provedene biološke mjere, dvije su bile kontrolne (jedna na blagom nagibu i s autohtonom degradiranom šumskom vegetacijom, a druga, jako erodirana, na strmom nagibu). Jedna ploha na blagom nagibu uspostavljena je 2004. godine – iskrčena je sva drvenasta vegetacija. Godišnja je količina oborine bila između 908mmu 2005. godini, preko 979mmu 2006. godini do 1 167mmu 2007. Više od polovice erozijske produkcije odvija se u 3. kvartalu godine. Istraživanja su pokazala da se biološkotehnič kom sanacijom povećava vodopropusnost tla i sadržaj organske tvari u tlu, to više što je strmije zemljište. Pokazalo se da je na zemljištu saniranom biološko-tehničkim mjerama vrlo niska erozijska produkcija, bez obzira na raspored i intenzitet oborine, a sama biološka sanacija, bez tehničkih mjera, rezultira značajno slabijim utjecajem na suzbijanje erozije., Soil erosion is one of the most devastating soil degradation processes. In temperate climate regions, soil erosion rarely assumes excessive proportions. In the management of forest soil, the potential erosion threat drastically increases with an increase in climate aridity. Water erosion is particularly favored by parent materials of low water permeability and by soils derived from such materials. In theMediterranean and sub-Mediterranean area of Croatia, these are primarily flysch, marl and Werfen schists. These materials show good physical weathering properties, thus providing a rich source of erosion material.As a rule, the soil formed from such parentmaterial is of silty-clayey to clayey texture, and has a relatively low infiltration capacity. The soil unprotected by vegetation (burned sites) manifests particularly devastating forms of water-induced erosion. In the past 50 years, flysch terrains of Istria have been subjected to a series of technical, biological and biological- technical treatments aimed at preventing water erosion and recovering the eroded soils. An experimental (research) site was set up in Abrami near Buzet for the purpose of monitoring erosion processes and rehabilitation effects of different biological-technical and biological methods of eroded area recovery. The effects of the treatments on soil properties in the research site are in the form of progressive pedogenetic processes. Asynergy of the effects of recovery methods and different natural conditions (relief, vegetation) in the experimental site is particularly well reflected in erosion indicators, such as the production of erosion sediment (erosion production), and to a lesser extent, the surface flow index. For this reason, research in this work focuses primarily on soil properties and erosion production dynamics. From the geological-lithological aspect, the research site of Abrami is made up of Eocene flysch composed of alternate layers of light grey marl and dark lime sandstone, i.

U radu su predstavljena pedološka istraživanja u tri smrekove zajednice na sjevernom Velebitu i u Štirovači: Aremonio-Piceetum Horvat 1938, Laserpitio krapfii-Piceetum Vukelić i dr. 2010, Calamagrostio variae-Piceetum Bertović 1975 nom. illeg. U tim su zajednicama uzeti kompozitni uzorci tla (13 kompozitnih uzoraka sastavljenih od po 9 pojedinačnih uzoraka) u površinskom sloju tla do 5 cm dubine i po pedološkim profilima (11 profila). Reakcija tla jedina je pokazala statistički značajne razlike za površinski sloj tla, i to za zajednice Aremonio-Piceetum i Laserpitio krapfii-Piceetum. Najniža pH-vrijednost u zajednici Aremonio-Piceetum uvjetovana je kiselim matičnim supstratom, zaravnjenim reljefom koji dodatno u uvjetima perhumidne klime pogoduje podzolizaciji, dok specifične mikroklimatske prilike, mrazište i visoka zračna vlaga utječu na intenzivnije nakupljanje sirovoga humusa. U odnosu na pH-reakciju najmanju kiselost pokazuje asocijacija Laserpitio krapfii-Piceetum, čime su potvrđena fitocenološka istraživanja (Vukelić i dr. 2010) prema kojima ta zajednica u odnosu na ostale ima najveći broj vrsta reda Fagetalia (Pawlovski i dr. 1928) koje su dominantne u okolnim, uglavnom neutrofilnim bukovim i bukovo-jelovim šumama. Sve tri istraživane zajednice Aremonio-Piceetum, Laserpitio krapfii-Piceetum i Calamagrostio variae-Piceetum u površinskom sloju tla do 5 cm pokazale su veliku onečišćenost olovom, a zajednice Laserpitio krapfii-Piceetum i Calamagrostio variae-Piceetum i veliku onečišćenost cinkom i kadmijem., The largest and the most coherent complexes of natural spruce stands in Croatia are currently distributed in the altimontane and subalpine vegetation belt of Velebit over an area of 3165 ha and altitudes ranging from 1100 to almost 1600 m. Past phytocoenological research into spruce forests in northern Velebit distinguishes three different associations: frost valleys of Štirovača and Apatišanska Duliba support the altimontane spruce forest with bastard agrimony (Aremonio-Piceetum Horvat 1938), shallower sink holes and slopes descending from the surrounding tops contain the altimontane-subalpine spruce forest with Laserpitium krapfii (Laserpitio krapfii-Piceetum Vukelić et al. 2010), while rocky tops, hips, karrens and ridges feature the subalpine spruce forest with small-reed (Calamagrostio variae-Piceetum Bertović 1975). These associations are distributed as azonal, microclimatically and edaphically conditioned associations, of which spruce forest with bastard agrimony occurs in the belt of Dinaric beech-fir forest (Omphalodo-Fagetum) while the two others grow in a higher belt of subalpine beech forest with buttercup (Ranunculo platanifoliae-Fagetum). Their mutual differences result from ecological factors which are decisive for their occurrence and distribution. Of these, the edaphic relationships which we explored in this work draw particular interest. Composite samples were taken from the top layer up to 5 cm deep (13 composite samples composed of 9 individual samples each), pedological profiles were opened (11 profiles), and soil samples were taken by pedogenetic horizons within pedological research in three spruce communities: altimontane spruce forest with bastard agrimony (Aremonio-Piceetum), altimontane-subalpine spruce forest with Laserpitium krapfii (Laserpitio krapfii-Piceetum), and subalpine spruce forest with small-reed (Calamagrostio-Piceetum) in the area of northern Velebit and Štirovača. Composite samples, taken from the top soil layer up to 5 cm de

The purpose of this study is to research the effects of different concentrations of mineral and biodegradable oils for chainsaws on seedling growth of pedunculate oak (Quercus robur L.) during two-year vegetation period. The paper also examines the influence of the above mentioned oils and their concentrations on the development of the seedling root system at the end of the second vegetation. Tests were carried out in forest nurseries on seven 1 m2 plots. Three plots were treated, after the planting of the pedunculate oak acorns, with biodegradable oil in the concentrations of 0.1 L/m2, 0.2 L/m2, and 0.5 L/m2. The other three plots were treated with mineral oil of the same concentrations. The control plot received only seed sowing. The analysis of the root system of the two-year-old seedlings of pedunculate oak was carried out with WinRHIZO ProLA 2400 software. The SAS and Statistica 7 program packages were used for the statistic data processing and for determination of statistically significant differences among variables. Results showed that the lower oil concentration the larger root lengths. The lowest heights of the two-year-old pedunculate oak seedlings were measured from the test plots treated with mineral oil and the highest on those from the plots treated with bio-oil, although the heights of seedlings from the control plots were very close to heights of those treated with bio-oil.