Šumarski list, Vol. 134 No. 5-6, 2010.
Izvorni znanstveni članak
Altimontane-Subalpine Spruce Forest with Laserpitium Krapfii (Laserpitio krapfii-Piceetum abietisass. nova)in Northern Velebit (Croatia)
Joso Vukelić
; Šumarski fakultet Sveučilišta u Zagrebu
Antun Alegro
; Prirodoslovno-matematički fakultet Sveučilišta u Zagrebu
Vedran Šegota
; Prirodoslovno-matematički fakultet Sveučilišta u Zagrebu
Sažetak
This research describes a new association of spruce with La serpitium krapfii(Laserpitio krapfii-Piceetum abietisass. nova). Occurring in the subalpine belt of northern Velebit, it reaches altitudes between 1,200 and 1,600 m. Here, the association is developed as a permanent stage under the strong influence of the microclimate of more humid, colder and shadier sites. Locally, it descends into sinkholes and lower slopes all the way to the beech-fir forest (Omphalodo-Fagetum). It is generally incorporated within the belt of pre-alpine beech forest with large white buttercup (Ranunculo platanifo liae-Fagetum). Some stands are highly productive, but in a large part of the range the community has a protective character.
The phytocoenosisLaserpitio krapfii-Piceetumhas macro-climatic featu res of the prealpine beech forest, in whose belt it is situated. However, its oc currence is predominantly determined by the microclimate modified primarily by the relief, altitude and other geomorphological factors (Cindrić 1973). The average annual temperature of the subalpine belt of northern Velebit is 3.5 °C, and the average annual precipitation is 1,898 mm (in the period 1961–1990, data from the State Hydro-Meteorological Institute). The parent material is made up of limestone breccias and limestone-dolomite blocks which often re surface. The soil is organogenic and organomineral calcomelanosol in mo saic with calcocambisol. In relation to calcomelanosols of other forest communities in the Zavižan area, calcomelanosols in this community are the richest in total nitrogen and humus content. Martinović (in Cestar et. al. 1977) found neutral reaction and base saturated adsorption complex in the humus-accumulative horizon and in the cambic horizon in calcomelanosols. He attributes his finding to the fragmented dolomitized limestones and brec cias which supply the soils with ample quantities of calcium. It is very impor tant to point this out, because in relation to other spruce associations, the studied Velebit community is significantly richer in species of the order Fage talia. The average soil pH determined in water for the depth layer of 0–5 cm amounts to 5.50.
Table 1 presents 12 phytocoenological relevés of the association Laserpitiokrapfii-Piccetumwith 140 species of higher plants and 25 moss species. Of this, 58 species of higher plants and 6 species of moss occur in more than 40 % of the relevés. Spruce is completely prevalent in the tree layer and is fre quently accompanied by beech (often deformed and of poor vitality) and mountain ash, while the bottom of the sinkholes and the lower positions are reserved for fir. The shrub layer, in addition to the species from the tree layer, contains another 16 species. The dominant species includeRubus idaeus,Vac cinium myrtillusand Rosa pendulina. Rubus saxatilisis dominant in more stony areas and Daphne mezereum in more temperate areas. The ground ve getation contains 119 species, of which 48 participate with the 3rddegree and more. Of 25 moss species, Dicranum scoparium, Polytrichum formosum, Cte nidium molluscum, Tortella tortuosa and Isothecium alopecuroides occur in over 40 % of the plots.
From the sociological standpoint, the dominant species are so-called “pi cetal” ones, characteristic of spruce forests in the larger part of Europe. Among them, Polystichum lonchitis, Luzula sylvatica, Veronica urticifolia, Valeriana tripteris, Adenostyles alpina, Hieracium murorum, Oxalis aceto sella,Homogyne sylvestris,Gentiana asclepiadeaand others have the highest participation. Together with mosses, there are 36 species in all. Other signifi cantly represented higher categories and lower units include as many as 39 species of the order FagetaliaPawl. 1928 (22 species with over 40 %). The al lianceAdenostylionBr.-Bl. 1925 and the order AdenostyletaliaG & J. Br.-Bl. 1931 are represented with 20 species, of which 9 with over 40 %. In terms of participation, species of the order Erico-PinetaliaHorvat 1959,Cirsium eri sithalesandCalamagrostis variaare very important. Other categories contain 69 plant and moss species, of which 13 occur in over 40 % of the relevés.
The speciesLaserpitiumkrapfii and Campanula velebitica are characteri stic of the association,Knautia drymeia,Petasites albus,Mycelis muralisand Mercurialis perennisfrom the Fagetaliaorder are differentiating species, whe reas Hypericum richerisubsp.grisebachii,Valeriana montana,Geranium syl vaticumandTrollius europaeushave prominent diagnostic importance. The association belongs to the suballianceVaccinio-PiceenionOberdorfer 1957, although the participation of elements of the suballiance Abieti-PiceenionBr.-Bl. in Br.-Bl. et al. 1939 is somewhat higher. However, the synecology of the subalpine belt, the complete dominance of spruce and the secondary role of fir, as well as the presence of species of the subalpine belt, firmly indicate the suballianceVaccinio-Piceenion. The abundance of differentiating species of subalpine in relation to montane spruce forests include Valeriana montana, Rubus saxatilis, Cirsium erisithales, Viola biflora, Polystichum lonchitis, Trollius europaeus, and slightly lessSaxifraga rotundifolia.
According to the Code of Phytocoenological Nomenclature (Weber et al. 2000), relevé No. 5 in the fifth column of Table 1 is the nomenclatural type.
Table II analyzes the relationship of the association towards related spruce subalpine associations in Croatia and in adjacent areas, ranging from the pre-alpine region to the central Dinaric range. Column 1 contains an important zonal association of the pre-alpine and alpine phytogeographic area of Slove nia and south Austria (Adenostylo glabrae-PiceetumM. Wraber ex Zukrigl 1973 corr. Zupančič 1999), while column 2 presents the community from the subalpine belt of the Dinaric phytogeographic area of Slovenia on carbonate parent material (Lonicero caeruleae-PiceetumZupančič (1976)1999). Co lumns 3 and 4 present Horvat’s association ”Picetum subalpinum croaticum”, mainly from western Croatia. Column 5 shows 6 relevés of the association “Calamagrostio variae-Piceetum” (nom. invalid) from northern Velebit (Ber tović, 1975), and column 6 presents 12 new relevés of the association Laserpi tio krapfii-Piceetum. Columns 7–9 feature subalpine spruce forests of Bosnia and Herzegovina, two of which /column 7,Sorbo-PiceetumFukarek 1964, column 8 Piceetum(illyricum)subalpinumHorvat 1950listeretosumethomo gynetosumFukarek 1969/ were taken from Zupančič’s analysis (1990). Co lumn 9 provides seven relevés from Vlašić (Lakušić et al. 1982).
The floral composition of spruce forests in Velebit, in relation to other Di naric spruce communities, is characterized by lesser participation and cover of Alpine-boreal species (Lonicera nigra,Lycopodium annotinum,Huperziaselago, Listera cordata, Calamagrostis arundinacea, Rhytiadelphus loreus) and higher participation and cover of the species from the Fagetalia order and lower units. This is attributed to several reasons, such as the biogeograp hic position of Velebit and the resulting ecological factors, the lithological-pe dological properties of the substrate and the influence of a strong beech belt which surrounds smaller complexes (and fragments) of coniferous forests. West Croatian and particularly Slovenian spruce forests are under a strong Alpine influence, while Bosnian-Herzegovinian spruce forests have retreated deep into the continental part. It is therefore logical that the association La serpitio krapfii-Piceetummanifests a more “fagetal” character and that its composition contains species of beech forests that are either absent from other spruce associations or are much less represented. Compared to the subalpine spruce forest “Calamagrostio-Piceetum” described earlier, the new associa tion occurs at lower positions and covers more humid, colder, shadier, much less stony and soil-rich sites. Locally, it descends into sinkholes and lower slo pes to the altitude of 1,100 m. Fir is still considerably present, but the other mentioned association is above the upper fir boundary.
Typologically, the association Laserpitio krapfii-Piceetumcan provisiona lly be divided into three types of stands. Stands with a standard composition are found on upper and centrally positioned, shady, moderately fresh slopes with an average floral composition. They frequently contain equal amounts of species from the order Fagetalia. The second type occurs on drier, more illu minated, more exposed localities that also include meadow edges (most fre quently Nardetum strictae), while the third type of stands is developed in narrow and restricted sinkholes and on the slopes leading to them. Species of the order Adenostyletaliadominate on colluvial soils with more moisture and longer presence of snow. Cicerbita alpina,Ranunculus platanifolius,Stellarianemorum,Poa hybridaand some others are particularly prominent. In some earlier research into spruce forests of northern Velebit (Vukelić and Tomljano vić 1990), this stand type was identified as an independent associationAdeno stylo alliariae-PiceetumHartman 1994.
Ključne riječi
Hrčak ID:
57001
URI
Datum izdavanja:
30.6.2010.
Posjeta: 2.380 *