Forest Growth Conditions Research Articles

Changes in expression of BetV1 allergen of silver birch pollen in urbanized area of Ukraine

The aim of the study was to determinate the level of expression of silver birch allergen Betv1 in pollen samples from different Ukraine areas by RT-qPCR SYBR Green assay. Protocol for quantifying the expression of Betv1 allergen was developed when testing of three housekeeping genes—cyclophylin, alpha-tubulin and transcription factor CBF1. Samples from urbanized area was analysed by real-time PCR when a sample from forest growth conditions was used as a calibrator. Real-time PCR based quantifying of Betv1 provides a useful method for rapid and sensitive analyses of this silver birch allergen. Our results show higher expression levels in samples from central parts of urbanized area as housing estates when compared to the samples from borders of the urbanized area.

Structure of Alnus fruticosa Rupr. s. l. and its relationships with other taxa of subgenus Alnobetula (Ehrhart) peterman

The reliability of morphological parameters of Alnus fruticosa s. l. on the territory of Asian Russia was studied. It has been revealed that the species has a complex internal structure stipulated by the climatic and forest-growing conditions in different parts of the range. The results of phenotypic variability and sequences of internal transcribed spacer ITS1 of nuclear ribosomal DNA of the taxa of the subgenus Alnobetula indicate the species rank of Alnus viridis and subspecies rank of A. fruticosa, A. sinuata, and A. crispa with the priority species name A. crispa. A. maximowiczii, A. glutipes, A. kamtschatica, and A. mandshurica are the result of intraspecific variability of the polymorphic species A. fruticosa.

Evaluation of the forest growth simulator SILVA on dominant trees in mature mixed Silver fir–Norway spruce stands in South-West Germany

Forest growth simulators go beyond a mere tabulation of empirical measurements by employing biometric models that functionally describe the dependence of forest growth of the initial forest structure, growth conditions and management regime. This makes them very flexible and allows predicting growth reactions for unknown and/or complex forest growth scenarios. When simulation outcomes are to be used in silvicultural strategic planning, the results are of direct and delicate importance, and the correct simulator performance must be ascertained. This is especially so when the considered forest situation differs from the forest data used to parameterise the model (e.g. different geographical region). In this article, the forest growth simulator SILVA (version 2.2) was validated for 55 long-term experimental plots of mature mixed Silver fir–Norway spruce stands in southwest Germany ( Picea abies, Abies alba). The evaluation was restricted to the upper canopy trees during the survey period 1989–2004. Following the general evaluation criteria for ecological models from [Vanclay, J.K., Skovsgaard, J.P., 1997. Evaluating forest growth models. Ecol. Mod. 98, 1–12], a specific methodology was developed to evaluate the simulated height and diameter growth on the basis of forest growth principles. The qualitative analysis proved the SILVA growth algorithms to be in accordance with physiologically based standard growth equations. The quantitative evaluation was limited by incomplete knowledge of the site conditions. To overcome this problem, the experimental plots were regarded as a “heterogeneous growth series” which allows analysing the growth behaviour in a more general way. It could be shown that for the given data set, the SILVA simulations produced an overestimation of height growth (median: +61% spruce, +12% fir), and an underestimation of diameter growth and competition sensitivity (median: −16% spruce, −70% fir). The errors partially compensated in the volume growth resulting in an overall over-/underestimation of +9% for spruce and −58% for fir (median). The unbalanced height and diameter growth cannot be compensated by a change in the site conditions because this affects both height and diameter growth either positive or negative. Hence, an adjustment of selected parameterisation values appears to offer the best solution to adapt SILVA to the considered forest situation. This approach of adaptive parameterisation is discussed against a more general background of deductive vs. inductive forest growth modelling.

Forest development on Kihnu Island and the role of the human factor in it

Kihnu saare metsade areng ja inimfaktori osa selles Of the total area of Kihnu Island (16.38 km2), 26% is under a 420-ha pine forest growing on sandy soils and dunes. The forest was estimated to cover about 130 ha (8%) in the early 19th century and 180 ha (11%) in 1949. In 1829-1935 the island's forest was managed predominantly by means of clear cuttings of 1.1 ha in size. Thereafter, it was treated as protection forest. In parallel with clear cutting, clear-cut areas and bare sandy zones were afforested where necessary. Altogether, 210 ha of forest plantations were established in 1829-1949. Intensive forest management and collateral use of forest (grazing on woodlands, gathering of forest litter) led to the impoverishment of the forest soils and stand diversity and deterioration of the forest growth conditions. In the last 75 years the island's forest has effectively enjoyed the status of protection forest, and its area has increased due to shrinking farming activity.

Soil-dependent uptake of 137Cs by mushrooms: experimental study in the Chernobyl accident areas

The influence of agrochemical properties of forest soils and growth conditions on 137Cs aggregated transfer factors from soil to different species of forest mushrooms have been analysed. Statistically significant correlations between 137Cs soil to mushroom aggregated transfer factors and agrochemical soil properties have been revealed. The experimental data show that 137Cs aggregated transfer factors depend on the mushroom's trophic group, biological family, genus and species. They also strongly depend on forest soil properties and their values can be estimated with the use of multiple regression equations constructed from agrochemical soil parameters which most closely correlate with the 137Cs transfer parameters for particular mushroom groups.

Spatial patterns of past wood exploitation, natural wood supply and growth conditions: indications of natural tree species distribution by anthracological studies of charcoal-burning remains

In close-to-nature silviculture one strives to derive the advantages of the natural adaptations of tree species to different growth conditions. Evidence of the natural distribution of tree species is obtained through vegetation science (recent ground vegetation, primeval forest relicts), studies of old written sources, and pollen and macrofossil analyses. Here we have analysed macrofossil samples of charcoal kiln sites and the recent ecological conditions in the vicinity of these sites, as well as secondary written sources on forest and land-use history. From charcoal analysis of kiln sites we were looking for spatial patterns of past tree species exploitation, with special regard to regional and local differences in the forest growth conditions and the natural wood supply. Therefore, we selected remote forest areas characterised by a high density of kiln sites and significant differences in the ecological conditions. The sample sites ranged over a landscape profile of 40 km, covering many ecological site types. The anthracological results of 181 post-medieval kiln sites were evaluated, considering two spatial scales: the total 40-km profile and a fine-scale profile of 4 km. Considering the charcoal material analysed as a whole, all of the tree taxa to be expected based on the natural conditions were found. The frequencies of the exploited taxa also reflected a natural situation. Wood of the climax vegetation, Fagus, Abies and Picea, was mainly used and all other taxa were quantitatively unimportant. The results for the individual sites showed considerable differences in taxa composition, from which regular spatial patterns of the past tree species distribution were deduced. These regional and local patterns are explained by natural differences in the ecological conditions in the vicinity of the sample sites. At the same time, new indications of the natural tree species composition of our forests are inferred. A pronounced dependency of charcoal production on the local natural wood supply is discernible. No indications of tree species selection or forest degradation could be found.

Sources of weathering‐derived solutes in two granitic catchments with contrasting forest growth

AbstractChemical weathering is one of the controlling factors for landform evolution. Here, we present deductions about the location and rate of chemical weathering within catchments based on chemical observations of soil water, groundwater, springs, and streams in two granitic catchments with contrasting forest growth conditions (forested and non‐vegetated) and soil development. The two catchments are located in the Tanakami Mountains of central Japan, and share the same climate. In both catchments, SiO2 and Na+ are the dominant weathering‐derived solutes in the first‐order stream. Using hydrological evidence, the contribution to the SiO2 and Na+ fluxes from soil and bedrock were partitioned. Despite the difference in mean soil depth, net fluxes of SiO2 and Na+ from the soil profile do not differ much between the two catchments, suggesting low levels of easily weatherable minerals in the forest soil. Net SiO2 and Na+ fluxes from bedrock are about three times greater in the forested catchment than in the bare catchment, and these differences contribute largely to the difference in net fluxes from the catchments. Net fluxes of SiO2 and Na+ from the forested catchment are about twice those from the bare catchment. Part of this increase may be related to the greater proton production in forested catchment. Consequently, about 60 to 70% of the net SiO2 and Na+ fluxes from the non‐vegetated catchment, and 70 to 90% from the forested catchment, are derived from bedrock, suggesting that the contribution of bedrock to the export of these weathering products increased with forest growth and soil formation. Copyright © 2004 John Wiley & Sons, Ltd.

Simulation of multi-species tropical forest dynamics using a vertically and horizontally structured model

The mutual interaction of forest growth and light conditions causes vertical and horizontal differentiation in the natural forest mosaic. The associated physical processes should be represented in simulation models describing long-term forest dynamics. The FORMIX2 (tropical) forest simulator incorporates the multi-storey canopy layer structure of the natural tropical forest, the basic processes of gap succession dynamics and gap interaction by tree fall and seed dispersal, several functionally different species groups (emergents, main canopy trees, pioneers, woody treelets and forest-floor herbs) and the energy (carbon) balance of assimilation, dissimilation, and increment resulting from the differing light conditions for the various canopy layers in the gap-size areas of a forest mosaic. The vertically and horizontally structured FORMIX2 model produces time-dependent results (average per hectare data) for stem numbers, diameter distributions, basal areas, standing crop and yield, as well as dynamic views of the forest profile and of spatial forest development, as a function of logging method and intensity and silvicultural treatment. The model has been applied in an exploratory investigation to compute the long-term development of (a) virgin forest and (b) logged-over forest in Sabah, using prototypical data. The results obtained agree with empirical data.