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1

A boreal-temperate transect in Europe: history of pine stands reconstructed from the radial growth of trees

100%
Parn H.
Polish Journal of Ecology
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2003
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tom 51
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nr 4
History of the Scots pine sites along the Finland-Poland boreal-temperate transect along 25°E longitude, ranging from 50°N-70°N latitude (see Fig. 1 in Breymeyer 2003) was reconstructed using tree-rings. The correlation between the tree-ring index chronologies for the sites was studied. The age of trees at particular sites varies in the range from 66 to 178 years. The youngest trees are growing at the sites FN3 and PL3, the eldest at FN1. At the sites FN1 and PL1, two groups of trees of different age were separated. Correlation analysis revealed significant correlation among the Baltic chronologies. High correlation coefficients were also found between the PL2 site chronology and all the Baltic state chronologies. No positive correlation was detected among the chronologies from the sites in Finland and in Poland.
2

Pine ecosystem response to warming along North-South climatic transect in Europe: presentation of research project

84%
Breymeyer A.
Polish Journal of Ecology
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2003
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tom 51
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nr 4
An attempt was made to evaluate the response of the ecosystem to changes of climate in ten pine forest stands. It was assumed that the ecosystem response to environmental change can be evaluated by examining differences in ecosystem structures and would be measured through the change in the rates of ecosystem processes. The changes of structures and rates are registered along the longest, N-S transect available on the European Continent above 50°N. This transect is within the belt crossing Northern Scandinavia (Norway and Finland up to 70°N), the Baltic States (Estonia, Latvia, Lithuania) and Eastern Poland (from 50°N). The transect covers 20 degrees of latitude and is more than 2000 km long. The difference in average annual temperature (long-term measurements) between the two extreme sites exceeds 9°C, and there is a regular southward increase of average site temperature. Precipitation does not show any regular pattern of change along the transect. Average site elevation is 86 m a.s.l., and the average forest age 110 years. All sites are dominated by an overstory of Scots pine, and in the Braun-Blanquet classification they all belong to Vaccinio-Piceetea class of forests, which are common in Europe. During four years of study (1997, 1998, 1999 and 2000) four expeditions to the transect were organized. The following studies were conducted on each site: the origin and structure as well as physical and chemical features of soils; tree stand age, height, basal area, biomass and carbon content; vertical and horizontal structure of ground vegetation, its diversity, biomass and carbon content; litter fall, its decomposition and accumulation; and radial growth of trees.
3

Rate of change of pine litter fall and decay in response to changing climate along N-S transect

84%
Breymeyer A.
Polish Journal of Ecology
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2003
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tom 51
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nr 4
The response of pine ecosystems to changing latitude and thermoclimate in Central/Northern Europe was investigated through the measurements of rates of two ecosystem processes: organic matter (litter) production and decomposition. Studies were carried out at nine sites of pine and mixed pine forests placed along the N-S transect of about 2000 km crossing Finland, Estonia, Latvia, Lithuania and Poland. Warmer climates were observed with movement to southern sites; the coefficient of determination (R2) between annual long-term temperature and latitude was at the level of 0.99. The rates of change of both processes were compared in terms of relative increment per 1°C of long-term temperature and per -1° of latitude, and expressed in %. Litter production responds stronger to the southward change of climate: the fall of litter is 18-19% greater per +1°C of average annual temperature and by 8% greater per each -1° of latitude, compared to the decomposition process, which was accelerated at the rate of 9-12% per 1°C and 4-5% per -1° of latitude. These results are summarized by the statement that in pine ecosystems the OM Production Sub-system is more sensitive to change of climate than the Sub-system of OM Decay, which is more conservative.
4

Changes in herb layer heterogeneity of Scots pine forests along the North-South transect

84%
Solon J.
Polish Journal of Ecology
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2003
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tom 51
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nr 4
The purposes of the present paper are: a) to show the synusial structure of the herb layer often sites, located in Norway, Finland, Estonia, Latvia, Lithuania and Poland along the transect stretching between 50°28′ and 70°09′ N, and b) to characterise the species-area curves for all the sites studied. The number of types of synusiae on the particular sites ranges from three to ten, though only one or two have the dominating character, that is, occupy at least 20% of surface. From the point of view of synusial differentiation three geographical groups of sites could be established: the most distinctly different are the northern sites. The second subset of sites, though featuring relatively weak internal mutual similarities, encompasses the sites located in the middle part of the transect. The third subset of sites, represents a more southern character. For each of the sites separately the dependence between the number of vascular species of the herb layer and the area of the site considered (the species-area relationship) is described by the formula y = axb. Correlation coefficients between the model and the actual number of species are very high, from 0.902 to 0.998.
5

Scots pine [Pinus sylvestris] ecosystem response to climate on a temperate to boreal forest transect: project description

84%
Reed D., Breymeyer A., Degorski M., Noble R.
Polish Journal of Ecology
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2003
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tom 51
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nr 4
This brief paper describes the history and conceptual framework underlying the research presented in the remaining papers in this volume. This project began in 1996 as an international effort to examine Scots pine (Pinus sylvestris) ecosystem structure and function in one of the few accessible areas on earth where similar forested ecosystems exist over a 20° range in latitude. Widely predicted climate warming leads to serious concerns about how ecosystems may respond to stresses created by climate change. In order to recognize evidence of warming and to predict likely future responses, it is necessary to understand how ecosystems that are distributed along climatic gradients accommodate wide climatic differences. Few tree species are distributed as widely as Scots pine, which ranges over much of Europe. This species is ideal for investigations that address questions regarding climate change effects on forest ecosystem structure and processes. Its distribution over comparable sites extending from temperate to boreal zones (over more than 20° of latitude from northern Finland to southern Poland) permits characterization of this ecosystem over a relatively wide climatic range (covering a mean annual temperature difference of 9°C). This transect: 1) provides information concerning numerous ecological processes over this wide range of conditions; 2) serves as a template for the development, testing, and evaluation of specific ecological indicators related to climate change; and 3) allows evaluation, comparison, and projection of ecological properties and processes among similar ecosystems with varying climate.
6

Epiphytic lichens diversity and chemistry on Scots pine forests along the transect from Northern Finland to Southern Poland

67%
Martin L., Martin J.
Polish Journal of Ecology
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2003
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tom 51
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nr 4
Along the north-south transect crossing much of the distribution of the Pinus sylvestris forests in Europe, 22 epiphytic macrolichen species were identified. Three of them, Hypogymnia physodes, Imshaugia aleurites and Parmeliopsis ambigua had wide distribution. Analysis of chemical element contents in H. physodes and corresponding pine bark samples demonstrated relatively high correlation. Elements such as copper, nickel, cadmium, sodium and phosphorus had higher concentrations at the Kevo (FN1) site and lead, iron and sulphur content was higher at Polish forest sites in southern part of the transect.
7

Woody biomass and annual production across a latitudinal gradient in Northern Scots pine [Pinus sylvestris] forests

67%
Nagel L. M., Vucetich J. A., Reed D. D., Mroz G. D., Parn H.
Polish Journal of Ecology
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2003
|
tom 51
|
nr 4
To better understand how forest growth might be affected by climate, we observed patterns of forest growth (in terms of basal area, diameter, canopy height, and total biomass) in Scots pine forest ecosystems at nine stands along a northern latitudinal gradient (50°N-70°N) crossing Poland, Lithuania, Latvia, Estonia, and Finland. This gradient is characterized by a northward decline in average annual temperature (Δ = c. 9°C) and precipitation (Δ = c. 300mm). Basal area, average diameter, canopy height, and total biomass appear correlated with average annual temperature (P-values range from <0.002 to 0.096), but were not correlated with average annual precipitation. None of the measures of absolute growth or percent growth rates (averaged over four measurement periods) were correlated with temperature or precipitation. A framework for evaluating recent increases in biomass pools in northern systems is given, but data here are of insufficient power to confirm or refute hypotheses of recent increase in production of northern forests.
8

Processes of litter fall and decomposition: boreal-temperate transect studies of pine ecosystems

67%
Breymeyer A.
Polish Journal of Ecology
|
2003
|
tom 51
|
nr 4
The processes of litter production and decomposition were studied in pine and mixed pine forests (10 sites) distributed along the N-S transect in Europe. The transect stretched from 70°N in Northern Finland and Norway to 50°N in Southern Poland. Mean annual temperatures change regularly along the transect from -1.9 to +7.4°C, while precipitation does not show any distinct pattern. Annual production and decomposition of litter are stimulated by warming. The primary factors governing the rates of both processes are related to thermic regime, most frequently to the long-term temperatures registered in the meteorological stations in the vicinity of sites. Correlation between decomposition rate and temperature (R2) range from 0.75 to 0.93, between decomposition rate and latitude from 0.72 to 0.80, and between decomposition rate and precipitation from 0.52 to 0.63 (in the last case only correlations with long-term precipitation are significant). Correlation coefficients R2 between litterfall and temperature range from 0.53 to 0.80, between litterfall-latitude from 0.72 to 0.80, and between litterfall-precipitation from 0.52 to 0.63 (significant only for long-term precipitation). With increasing temperature decomposition rates increase from about 0.09 g.g⁻¹.y⁻¹ (needles 0.13 g.g⁻¹.y ⁻¹, wood 0.06 g.g⁻¹.y⁻¹) in the North to about 0.32 g.g⁻¹.y⁻¹ (needles 0.41 g.g⁻¹.y ⁻¹, wood 0.18 g.g⁻¹.y⁻¹) in the South. Litterfall increases from 103.19 g.m⁻².y⁻¹ (in this needles 56.73 g.m⁻².y⁻¹, wood 45.59 g.m ⁻².y⁻¹) in the North, to about 419.36 g.m ⁻².y⁻¹ (needles 203.95 g.m⁻².y⁻¹, wood 203.56 g.m⁻².y⁻¹) in the South. OM annual accumulation increases southward, ranging from about 100 (North) to about 370 (South) grams per m2. Accumulation is strongly connected with air temperatures on the sites (correlation coefficients (R2) at around 0.9).
9

Morpholithological genesis and soil properties of the pine forest ecosystems in relation to the North-South transect in Europe

67%
Degorski M.
Polish Journal of Ecology
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2003
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tom 51
|
nr 4
The influence of the geographically differentiated pedogenic factors on the properties of the podzolic soils of the pine forest ecosystems located along a meridional transect stretching between northern Finland (69°44′ N) to southern Poland (50°28′ N) was studied. The geographical trends in soil properties and the diagnostic soil features were determined. The results of many years of research on the spatial differentiation of the properties of podzolic soils confirmed the relations between the geographical differentiation of the pedogenic factors, the spatial variability of the structures of the soil cover, and the spatial variability of soil properties. In addition, an essential role of the soil in the functioning of boreal pine forest ecosystems was demonstrated. The following results can be drawn on the basis of the results obtained: 1) the spatial differentiation of the soil cover analysed is associated with the age of the original sedimentation, the texture properties of the substrate from which the pedons developed, the hygro-thermal properties of climate, and the structure of the vegetation cover; 2) along with the increase of the age of the soils towards south and the decrease of the humid character of climate the increase of the following parameters was noted: content of quartz and of the resistant minerals, the value of grain abrasion index (Wo), the value of the nonhomogenous index (Nm), the deficit of moisture, the thickness of the soil's solum, the ratio Ch:Cf, the degree of humification, the absolute content of the hydrogen ions, the contents of the bivalent cations in the sorption complex of the soils. The decrease was also noted of: the content of the non-resistant minerals, the value of the average grain diameter indicator (AGD), the thickness of the organic horizon (O), the storage of the organic carbon in the entire pedon, the content of the ammonia salts in the mineralised nitrogen, the saturation of the sorption complex of the soils with hydrogen cations, the total content of phosphorus and of the phosphorus accessible for plants, the value of the Schwertmann's indicator, and the value of the illuviation indicator after Mokma; 3) the highest ecological efficiency, as measured with the enzymatic activity, is displayed by the soils of the central part of the area considered.
10

The rate of changes in the radial growth of pine trees along the latitudinal transect between 50-70 degrees N

67%
Parn H.
Polish Journal of Ecology
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2003
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tom 51
|
nr 4
The rate of change of pine radial growth was evaluated for 9 sites of forest located on the latitudinal transect. The average widths of tree rings of Scots pine trees at the ages 20 to 60 years were selected from long-term (70-170 years) measurements collected on the transect sites. The tendency to increasing radial growth noted southward, was associated with increasing growing season temperature and decreasing latitude. The rate of change of radial growth expressed in % per 1°C of average annual temperature and -1°N of latitude equals 2.40% (per 1°C) and 1.22% (per -1° latitude).
11

Carbon pools and storage along a temperate to boreal transect in Northern Scots pine [Pinus sylvestris] forests

67%
Reed D., Nagel L.
Polish Journal of Ecology
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2003
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tom 51
|
nr 4
A significant portion of global terrestrial carbon is stored in forested ecosystems, particularly in systems north of 50°N latitude. Carbon fluxes to and from these systems have the potential to greatly influence global terrestrial C storage, and provide feedback loops in the global carbon cycle. This study examines total ecosystem C storage, and its allocation among ecosystem components, in nine study sites located in Scots pine (Pinus sylvestris) forests located from 50°N (southern Poland) to 70°N (northern Finland). Results indicate a remarkable similarity in total ecosystem C, despite great differences in physical appearance of the overstory. In the long-run, these results do not indicate a great deal of change in total C storage in these systems. The two component C pools that differ the most are the overstory biomass and the organic soil horizons; this raises the concern that these sites could be short-term sources of atmospheric C due to more rapid decomposition in the face of changing climate, but the overstory biomass could be a longer-term, possibly offsetting sink of atmospheric C.
12

Ground vegetation carbon and its relation to climate and species richness

67%
Solon J., Roo-Zielinska E.
Polish Journal of Ecology
|
2003
|
tom 51
|
nr 4
Ten pine forest sites located along the transect between 50°28′ and 70°09′ N were studied. The purposes of the present paper are: 1) to determine the volume of the organic carbon pool in selected layers of the analysed forest ecosystems (shrubs, herb layer, mosses and lichens, litter, and the humus horizon of the soil); and 2) to elaborate the correlation-based prediction models relating the organic carbon pools in these layers with the selected variables characterising the climate and the species richness of the pine forests. The results indicate a clear horizontal heterogeneity of the ground layer in the pine forests considered. This is reflected, in particular, through the differentiation of the carbon pool in particular places within the ecosystem. There is a distinct geographical variability in the carbon pool among the sites in particular layers, with the average annual and January temperatures having the largest influence on this variability. However, in different cases there are different combinations of the factors describing these relations in the best way. The relations between the carbon pool and the species richness of the sites along the transect show that either the minimal carbon pool occurs at sites of an average species richness, or there is no relation between these variables. The analysis implies that there are two points of the transect at which various characteristics of the system undergo an abrupt shift. The first of them is equivalent to the passage of the annual +1°C isotherm, while the second at approximately 5-6°C. There is the possibility that these regularities occur within the entire range of the pine forests.
13

Scots pine forests of the Vaccinio-Piceetea class in Europe: forest sites studied

67%
Solon J.
Polish Journal of Ecology
|
2003
|
tom 51
|
nr 4
The paper presents: a) the general differentiation of the pine forests of Europe, and b) the floristic differentiation of the ten study sites, located along the transect stretching between 50°28′ and 70°09′ N, as well as c) the relations between the geographical location and the climatic characteristics on the one hand, and the selected features of the richness and species diversity of the herb layer on the other. One can observe a dependence (p < 0.05) between the temperature and latitude on the one hand, and the number of species from some groups on the other. For the vascular plants, the indicators of linear correlation amount to, respectively, 0.64 and -0.63 (the number of the vascular species of the herb layer increases with the warming of climate and the movement towards the South), and for the numbers of lichen species: -0.81 and 0.78 (the dependencies have the opposite directions to the previous ones). The variability of the relative shares of the particular species groups is correlated with geographical location and climatic variables. Three basic patterns of spatial variability can in this context be identified. The first of these is represented by the share of the lignified chamaephytes (dwarfshrubs). In accordance with this pattern, the minimum shares are observed at the latitudes of Lithuania, Latvia, and Estonia. The second pattern of variability is represented by the shares of hemicryptophytes. In accordance with this pattern the maximum shares are observed between 53° and 56° N. The third pattern of variability is represented, in particular, by the share of the evergreen species which is proportional to the latitude.
14

Ecological groups of vascular plant species in the herb layer of the pine forests of Northern and Central Europe

59%
Roo-Zielinska E.
Polish Journal of Ecology
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2003
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tom 51
|
nr 4
The species of vascular plants of the herb layer, were studied on ten forest sites representing pine forests of the alliance Dicrano-Pinion. These sites are located along the N-S transect in Northern and Central Europe, between 50°28′ and 70°09′ N - in Norway (NO1), Finland (FN1, FN2, FN3), Estonia (ES1), Latvia (LT1), Lithuania (LI1), and Poland (PL1, PL2, PL3). The relation was determined between the geographical location of these forests and the proportion in total species number and cover of the plants in the herb layer with known ecological, habitat and climatic requirements for light (L) and temperature (T) and soil requirements for moisture (F), acidity (R), and content of nitrogen (N). The indication method was applied using the species scale of Ellenberg et al. (1991), indicating the climatic and habitat requirements of the plant species on the basis of the values of the L, T, F, R and N in the macroclimatic gradient. The species which behave in a similar manner with respect to the habitat factors mentioned were clustered into the indicator species groups. The distinct directional changes of the share of these groups along the North-South transect were observed: 1) gradual appearance of the species characteristic for the moderately warm areas; 2) decrease of the share of the hygrophilous and acidophilous species.
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