DIGITALNA ARHIVA ŠUMARSKOG LISTA
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ŠUMARSKI LIST 13/2005 str. 237 <-- 237 --> PDF |
P. Jaloviar: FINE ROOT DISTRIBUTION IN A PURE NORWAY SPRUCE POLE-STAGE STAND Šumarski list SUPLEMENT (2005), 229-237 the emergence of next forest generation (Jaloviar Norway spruce {Picea abies L. Karst.) is a typical 1999). The most of these factors can´t be affected direpresentative of the tree species with the flat root sysrectly, but e.g. the crown volume and microclimatic tem. The growth dynamics of its fine roots is autonoconditions in the stand are decisive impacted by silvi-mous, i.e. their growth stops in the summertime also in cultural interventions as well. the case of appropriate moisture conditions. The densi The influence of the initial spacing on the crown dety of spruce fine roots in the soil is very extensive. The velopment and the growth of Norway spruce is indispuincrement potential of its fine roots belongs to the lotable (Schmidt-Vogt 1991, Korpel ´ & Saniga west between our common tree species. The appearan1995). Assuming that the balance between the above-ce of physiological active fine roots is concentrated in ground and underground part of the tree is kept by the the soil horizon A. healthy individuals (Schinozaki etal. 1964), we can expect the spacing has an important influence on the fine root development and distribution in the soil as well. STUDY AREA AND METHODS The IUFRO spruce plant spacing experiment was plot D, spacing 2H2 m, stem density 2,500 ha"´ established on locality Vrch Dobroč in 1981-1982, the plot E, spacing 3H0.67 m, stem density 5,000 ha"1 plots with investigated spacings were established 1982 plot F, spacing 2.5H0.8 m, stem density 5,000 ha"1 and at present they are 21 years old. The plots are located in the elevation from 890 to 910 m, the slope ranges plot G, spacing 2.0H1.0 m, stem density 5,000 ha"´ from 8 to 15 % and it has west aspect. The area of each The samples for estimation of fine root biomass were plot is 0.4 ha. taken according to systematic sampling. In each spacing The soil on the plots is sandy loam cambisol that a line was marked, where in the distance of 50 cm the developed on crystalline rock. Average annual precipisoil cores up to the depth 40 cm were taken. On the plot tation is 900 mm. B 8 probes were established, on each other plot 7 pro bes. The samples were handled according to the metho The area of present spacing experiment was agri dology mentioned e.g. in the work of M u r a c h (1984). cultural land initially and therefore the homogeneity of the soil environment provides an unique possibility for The samples (soil cores) were taken by a hollow aucomparative studies. The low variability of the soil enger with the inner diameter 80 mm and the length of the vironment is an important advantage, because it don´t hollow part 200 mm. conceal the differencies of the root system developThe state (vitality) of the most fine roots can be ment due to e.g. various silvicultural interventions, identified from the macroscopic marks, in the questiospacing etc. Detailed description of the research area nable cases a binocular glass with the magnification can be found inKorpel´&Saniga (1994). 15x or 30x was used. This paper analyses following 7 spacings: After the drying of roots at 70EC the weight of both categories (vital and dead) was quantified. The acqui plot A, spacing 5H0.8 m, stem density 2,500 ha"´ plot red values were converted into the weight in kg on the B, spacing 4.0H1.0 m, stem density 2,500 ha"1 area of 1 ha or into the values of fine root density in mg plot C, spacing 3.OH 1.3 m, stem density 2,500 ha"´ of 100 ml of soil. RESULTS AND DISCUSSION The comparison of particular spacings according to fine root biomass The production of the fine root biomass varies acThe nccromass weights are not so high as the biocording to the spacing as expected. Mostly vital fine mass weights and therefore they don´t impact the absoroots were found on the plot E with the spacing lute differencies in the total weights of both fine root 3.OH 1.3 m (8,817 kg.ha"´). This value is quite high, escategories either. pecially in the comparison with the data published for In the review of vital fine root biomass compiled by the mature stands. After the comparison with the stands Casper & Jackson (1997) the values range from 200 of other tree species in the same growth phase, acquito 5,000 g/m , i.e. after conversion from 2,000 kg/ha to red data can´t be consider extreme. At least vital fine 50,000 kg/ha. However, the authors have considered onroots were found on the plot F with the spacing 2.5 H ly mature forest stands. Korotaev (1997), who inves 0.8 m (3,945 kg.ha"´). tigated the fine root biomass in two 80 years old stands |