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T he paper deals with the succession of basidiomycete macrofungi on abandoned farmland. T T he research was carried out in the unique complex of old fields of different age located on the southwest edge of the Białowieża old-growth forest (NE Poland). T T hese lands undergo spontaneous secondary succession leading to formation of a continental fresh pine forest. Regular observations of basidiomata in 16 permanent plots (11 plots of 1000 m2, 5 plots of 400 m2) representing initial, optimal and terminal stage of vegetation development from psammophilous grassland to a pine forest with 100-year-old tree stand were conducted for three years. Soil and vegetation analyses were also carried out as well as quantitative examination of ectomycorrhizae in root samples. T he series yielded 300 species of macromycetes (including 6 collective taxa) found in permanent plots plus 18 species outside the plots. T T he species composition, spatial distribution of sporocarps, and quantitative structure of fungal communities changed along the successional gradient. Increasing diversity of fungi resulted from persistence of species typical of open areas and species associated with younger trees, as well as accumulation of species associated with older trees and more developed stands. Some species typical of younger phases were replaced with species arriving later in the chronosequence. Species usually occurred long before and after attaining maximum abundance and frequency. Species associated with certain periods of vegetation development could be distinguished, as well as species accompanying the phytocoenoses regardless of their developmental stage. Patterns in structural changes of the fungal community, e.g., in number of species, abundance, frequency and production of carpophores, could also be recognised. T T hey were different in ectomycorrhizal and in saprotrophic fungi. T T he occurrence of the former was influenced mainly by the presence of symbiotic trees and their age, stand structure and soil properties, while occurrence of the latter was affected by microclimatic factors and by diversity of accessible substrates. Changes in fungal communities were consistent with vegetation changes, but were also specific to this group of organisms.
We studied the chronosequence of six Scots pine (Pinus sylvestris L.) plantations (6-, 9-, 11-, 15-, 17-, and 20-years-old) to examine the changes in leaf area index (LAI) over stand age. The study site was located on a mine spoil heap (outer dumping ground) in the Belchatow lignite open-cast mining district (central Poland). The main goal of the study was to analyze LAI changes over stand age in a chronosequence of young Scots pine stands and to test the relationship between LAI estimates derived from a LAI-2000 Plant Canopy Analyzer and site-specific allometric equations. In addition, we tried to determine whether LAI estimated by a LAI-2000 PCA can be used to accurately estimate forest biomass. We hypothesized that LAI-2000 PCA underestimates LAI of the stands, and that stand age (and linked stand parameters) may influence the range of the hypothetical underestimation due to changes in biomass allocation. Our study revealed that LAI was highly dependent upon stand age and tree density (p<0.0001) regardless of the way how LAI was determined. Moreover, we found that LAI estimated by LAI-2000 PCA significantly correlates with stand biomass per area; the highest coefficients of determination were found for total aboveground biomass, aboveground woody biomass, and stem biomass. This means that data obtained by LAI-2000 PCA are good predictors of stand biomass in the young stages of stand development. In contrast to our prior assumption, the results showed that LAI-2000 PCA overestimates leaf area index. The relative differences between the values obtained with LAI-2000 and those calculated on the basis of the site-specific allometric equations increase with age. This may reflect changes in crown architecture over age caused by enlarging tree dimensions and over - crowding of trees leading to deterioration of light conditions inside the canopy.
The purpose of this study was to examine how stand age affects fine root biomass and morphology in different stages of first generation Scots pine forest development in post-agricultural fields. Stands of different ages (6-, 10-, 16-, 28-, and 47-yr-old) were studied at the same time to provide data on biometrical fine root features, i.e. biomass, length, surface area, volume, number of tips, root tip density, specific root tip density, specific root area, specific root length and fine root tissue density. Soil cores from the upper 20 cm of soil were used for the study. The results of the study show that fine root characteristics did significantly differ among stands of different age. Fine root biomass ranged from 0.9 Mg ha–1 (6-yr-old stand) to 2.3 Mg ha–1 (47-yr-old stand), whereas coarse root biomass ranged from 0.2 Mg ha–1 to 3.2 Mg ha–1, respectively. Fine root biomass in the older stands (10–47-yr-old) remains constant and is ca. 4 times higher than in the youngest stand (6-yrs-old). This shows that the fine root biomass of Scots pine in the upper soil horizons reached a constant biomass at a younger stand age than found in previously published papers, although at the same stage of stand development, i.e. canopy closure. Fine root length, surface area and volume expressed on per stand area basis were significantly different among stands; the highest values were found in the 10-yr-old stand, during the time of canopy closure. This means that stand age (i.e. age of trees in pure even-aged monocultures) is not a major factor influencing the fine root dynamics, instead stage of development and other stand and habitat characteristics may play an important role. Moreover, we found significant linear relationships among stand age and fine root length, surface area and number of fine root tips expressed on a per tree basis. Our study showed that stand age affects both fine root biomass and morphology in Scots pine forests when growing on post-agricultural fields. The differences revealed in our study indicate high plasticity of Scots pine fine roots in response to stand changes over age.
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In boreal and temperate forests fungi play a particularly important role, since most trees form a symbiotic relationship with many species of ectomycorrhizal (ECM) fungi, providing them with assimilates in exchange for minerals. Mycorrhiza is considered one of the most significant factors affecting functioning of forest ecosystems, and in particular the processes of carbon cycling and storage. ECM fungi are involved both directly through carbon accumulation in the mycelial system, and indirectly through their influence on tree biomass production and organic matter decomposition. The amount of carbon transferred to ECM fungi usually varies from 10 to 25 or even 50% of the host's net photosynthesis, thus they are a group of organisms that significantly affect carbon flow into the soil. Most of that carbon is built into the mycelial system and its structures (fungal parts of ECM roots, extramatrical hyphae and rhizomorphs, sporocarps, etc.). Carbon allocation to the underground part of trees, and thus to ECM roots, changes with stand age and stand development phase. The biomass of active ECM roots and mycelium usually reaches its maximum in young stands, in the canopy closure phase; frequently, this is also true for the standing biomass of fruit bodies. A large share of ECM sporocarps in the forest carbon budget and high levels of ECM vegetative mycelium respiration are considered to be among the main pathways for the release of CO2 from forest soil, indicating a significant role of ECM fungi in fast carbon flow via forest ecosystems. On the other hand, dead ECM fine roots and extramatrical mycelia are a very rich and important pool of sequestered carbon in the soil.
The morphology of fine roots ( 2 mm diameter) as well as fine and coarse root biomass was investigated in a chronosequence consisting of 6-, 9-, 11-, 15-, 17- and 20-year-old Scots pine (Pinus sylvestris) stands growing on a reclaimed lignite mine spoil heap. Core method of destructive root sampling was used to establish whether root morphology and biomass varied with stand age in the upper 20 cm of soil. Fine root biomass ranged from 0.78 to 3.11 Mg ha-1, coarse root biomass ranged from 0.82 to 2.74 Mg ha-1, whereas root necromass ranged from 1.03 Mg ha-1 to 2.87 Mg ha-1 in the chronosequence studied. Fine root diameter as well as length, projected area, and surface area expressed per unit area increased significantly with stand age. Moreover, our study revealed that when stand age increases, specific fine root biomass increases, whereas specific root length and area decreases. The results support our hypothesis that stand age has an effect on standing fine root biomass and morphology.
It is not clear to what extent trees growing on anthropogenic sites change their growth and biomass allocation to different organs. We assessed the aboveground biomass in a chronosequence of six Scots pine monocultures (between 6 and 20 years old) to examine how precisely the site-specific or control allometric equations may reflect the value of biomass accumulation and allocation in stands growing in harsh site conditions on the overlayer spoil heap made as a result of opencast brown coal mining. The site is characterized by poor edaphic and water conditions and nutrient deficiency. The control equations were developed from Scots pine stands growing on post-agricultural lands in the close vicinity of the spoil heap. We found that equation type significantly influenced results of predicted biomass accumulation for all biomass components studied (although results were only marginally significant for total aboveground biomass, P=0.08). Total aboveground biomass in younger stands (6–9 years old) estimated using site-specific equations was >40% higher and for older stands (17–20 years old) from 7 to 27% lower than estimated using equations developed for the control sites. Our study revealed that under harsh environmental conditions in spoil heaps, biomass of young Scots pine stands significantly differ from values calculated based on control equations developed for more fertile soils with better water conditions in the same region. The control biomass equations may not be suitable to estimate biomass accumulation in stands growing on infertile habitats with poor water conditions, if the control equations are developed for nearby stands but growing under better site conditions.
This paper presents the second part of the results of the first short-term inventory of fungi species occurring in the Biebrza National Park and is focused on a survey of macrofungi. The total number of macrofungi found during the survey in late August 2012 was 289 taxa: 17 ascomycetes and 272 basidiomycetes, inhabiting diverse ecological niches. The identified fungi belonged to ectomycorrhizal symbionts and saprobionts decomposing wood, plant litter and animal remnants. The identity of 25 mycorrhizal fungi species has been confirmed using molecular techniques. Five species are newly reported for Poland (Amanita olivaceogrisea, Lepiota lepida, Stropharia alcis, Xerocomus fennicus, X. cisalpinus) and 225 taxa (79 %) were not known in the Biebrza National Park. Fifty nine species are endangered in Poland, of which nine species are protected by law. Data on species richness and the taxonomic diversity of the identified fungi are briefly commented in terms of their significance for nature conservation and future research.
The paper gives a survey of biodiversity of planted grand fir (Abies grandis) stands in Rogów Arboretum on the background of environmental data compared to those of its natural distribution. Some information concerns studies on grand fir plantations in Europe and their influence on chosen components of the ecosystem. During the study, 63 taxa of vascular plants, mosses and liverworts, 46 taxa of fungi and 110 of invertebrates were found.
The paper gives a survey of biodiversity of noble fir (Abies procera) stands in Rogów Arboretum on the background of environmental data. Noble fir is native to the mountains of north-western United States. During the study in the Rogów Arboretum we have found 53 taxa of vascular plants and mosses, 51 taxa of macrofungi and 112 of invertebrates in Abies procera stands. The documented biodiversity of planted Abies procera stands has been commented with respective data from natural habitats.
The paper gives a survey of biodiversity of Greek fir (Abies cephalonica) stands in Rogów Arboretum on the background of environmental data. Greek fir is native to the southern and central Greece to the areas of the Mediterranean-montane climate. The data concerning differentiation and species composition of natural stands are not complete as well as those on Greek fir plantations in Europe. The study conducted in Rogów Arboretum has shown the presence of 62 taxa of vascular plants and mosses, 58 taxa of macrofungi and 132 of invertebrates.
The Balkan pine (Pinus peuce) is a Balkan Peninsula endemic tree species, growing in high mountains of Bulgaria, Macedonia, Serbia, Montenegro, Kosovo, Albania, and Greece and forming pure and mixed stands in subalpine forests. The paper gives a survey of biodiversity of Balkan pine stands in the Rogów Arboretum in reference to environmental data. In the plots examined, 29 taxa of vascular plants, 29 taxa of macrofungi and 127 taxa of invertebrates were recorded. The revealed diversity is discussed with regard to the data from Pinus peuce natural habitats.
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