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In the Kranzberg forest near Freising (Germany) a novel “Free-Air Canopy O3 Exposure” system has been employed for analysing O3-induced responses from sub-cellular to ecosystem levels that are relevant for carbon balance and CO2 demand of 60-year-old beech trees. The below-ground ectomycorrhizal community was studied in two-fold ambient O3 concentrations (five cores per sampling) and in a control plot with an ambient O3 concentration (four cores per sampling). Five samplings were taken throughout two vegetation seasons (2003 and 2004). Types
of ectomycorrhiza were determined by their morphological, anatomical and molecular characteristics and quantified by counting.
The total number of mycorrhizal fine roots was higher at the fumigated plot as compared with the control site. The numbers
of ectomycorrhizal types at the fumigated and control plots were 28 and 26, respectively. Cenococcum geophilum was present in all soil cores at all sampling times with a significant increase in abundance under ozone-fumigated trees.
Other mycorrhizal types present at higher abundance at the fumigated than at the control plot were identified as Russula densiflora, R. fellea, R. illota, Tuber puberulum, Lactarius sp. 2 and Russula sp. 2. Some mycorrhizal types were present exclusively at the fumigated plot (Fagirhiza fusca, F. setifera, Lactarius acris, Piceirhiza nigra and Russula sp. 1). A possible ecological role for the abundant types of ectomycorrhiza and their putative application in bio-indication
is discussed. 相似文献
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Kraigher H Al Sayegh Petkovsek S Grebenc T Simoncic P 《Environmental monitoring and assessment》2007,128(1-3):31-45
Mycorrhiza is the main spatial and temporal linkage between different constituents in a forest ecosystem. The functional compatibility
and stress tolerance of ectomycorrhizal types is species specific, and therefore the information on the ectomycorrhizal community
structure can add to the understanding of processes in forest ecosystems and can also be applied as tools for bioindication
of pollution stress in forest soils. We have studied the effects of pollution (N and S) on trees and forest soils by: (1)
quantification of ECM types diversity as in situ indicators in forest stands, (2) determination and quantification of pollution-sensitive or -insensitive ECM types as passive
monitors, (3) root growth and development of ECM on nonmycorrhizal spruce seedlings, planted at the studied sites (active
monitors), and (4) ECM infection (a bioassay based on mycorrhizal inoculum potential) of seedlings in an experimental set-up
as ex situ testers. ECM species richness for Norway spruce trees (Picea abies) showed higher values in unpolluted sites than in polluted ones, while the differences were not significant for European
beech trees (Fagus sylvatica). As pollution-sensitive or -insensitive ECM species in spruce forests, we suggest Hydnum rufescens (sensitive) and Paxillus involutus (unsensitive). Mycorrhizal potential in Norway spruce seedlings as a bioassay for soil N and S pollution was effective, and
is suggested as an additional, standardized and widely comparable system in bioindication of soil pollution. 相似文献
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R. Matyssek G. Wieser H. Rennenberg K. Haberer A.J. Nunn P. Wipfler P. Nikolova H. Kraigher G. Bahnweg J. Dieler K. Herbinger M. Blumenröther T.E.E. Grams M. Leuchner K.-H. Häberle 《Environmental pollution (Barking, Essex : 1987)》2010,158(8):2527-2532
Ground-level ozone (O3) has gained awareness as an agent of climate change. In this respect, key results are comprehended from a unique 8-year free-air O3-fumigation experiment, conducted on adult beech (Fagus sylvatica) at Kranzberg Forest (Germany). A novel canopy O3 exposure methodology was employed that allowed whole-tree assessment in situ under twice-ambient O3 levels. Elevated O3 significantly weakened the C sink strength of the tree-soil system as evidenced by lowered photosynthesis and 44% reduction in whole-stem growth, but increased soil respiration. Associated effects in leaves and roots at the gene, cell and organ level varied from year to year, with drought being a crucial determinant of O3 responsiveness. Regarding adult individuals of a late-successional tree species, empirical proof is provided first time in relation to recent modelling predictions that enhanced ground-level O3 can substantially mitigate the C sequestration of forests in view of climate change. 相似文献
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