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Article
Plasticity in hydraulic architecture of Scots pine across Eurasia
Widespread tree species must show physiological and structural plasticity to deal with contrasting water balance conditions. To investigate these plasticity mechanisms, a meta-analysis of Pinus sylvestris L. sap ...
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Chapter
Atmospheric and Structural Controls on Carbon and Water Relations in Mixed-Forest Stands of Beech and Oak
The natural vegetation of central Europe is dominated by European beech (Fagus sylvatica) increasingly mixed with pedunculate oak (Quercus robur) in dry lowlands and sessile oak (Quercus petraea) in lower montane...
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Chapter
Biogeochemistry of Two Forested Catchments in a Changing Environment: A Synthesis
The environmental conditions that influence the functioning of our catchments have changed substantially in the last two decades. These changes comprise chemical and physical properties of the atmosphere and t...
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Chapter
Impacts of Canopy Internal Gradients on Carbon and Water Exchange of Beech and Oak Trees
Identifying the relevance of forest structure for stand photosynthesis and transpiration is one of the remaining challenges in plant physiological ecology. While leaves and their stomata are the causal agents ...
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Chapter
Deciduous Forests: Carbon and Water Fluxes, Balances and Ecophysiological Determinants
Among the five EUROFLUX broad-leaved sites, four are beech stands and one is a poplar plantation. These sites are spread over a wide range of climatic conditions: mid-oceanic (France), continental (Germany) an...
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Article
The relationship between tree height and leaf area: sapwood area ratio
The leaf area to sapwood area ratio (A l:A s) of trees has been hypothesized to decrease as trees become older and taller. Theory suggests that A l:A s must decrease to maintain leaf-specific hydraulic sufficien...
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Article
Evaporation and transpiration from forests in Central Europe – relevance of patch-level studies for spatial scaling
Spatial scaling from patch to the landscape level requires knowledge on the effects of vegetation structure on maximum surface conductances and evaporation rates. The following paper summarizes results on atm...
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Article
Comparisons of xylem sap flow and water vapour flux at the stand level and derivation of canopy conductance for Scots pine
Simultaneous measurements of xylem sap flow and water vapour flux over a Scots pine (Pinus sylvestris) forest (Hartheim, Germany), were carried out during the Hartheim Experiment (HartX), an intensive observation...
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Article
Estimates of water vapor flux and canopy conductance of Scots pine at the tree level utilizing different xylem sap flow methods
During the Hartheim Experiment (HartX) 1992 conducted in the upper Rhine Valley, Germany, three different methods were used to measure sap flow in Scots pine trees via heating of water transported in the xylem...
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Article
The HartX-synthesis: An experimental approach to water and carbon exchange of a Scots pine plantation
In May 1992 during the interdisciplinary measurement campaign HartX (Hartheim eXperiment), several independent estimates of stand water vapor flux were compared at a 12-m high Scots pine (Pinus silvestris) planta...
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Article
Model-based estimates of water loss from “patches” of the understory mosaic of the Hartheim Scots pine plantation
During the Hartheim Experiment (HartX) 1992 conducted in the Upper Rhine Valley, Germany, we estimated water vapor flux from the understory and the forest floor by several methods. At the vegetation “patch” le...
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Article
An analysis of needle yellowing in healthy and chlorotic Norway spruce(Picea abies) in a forest decline area of the Fichtelgebirge(N.E. Bavaria)
In a forest decline area (Fichtelgebirge, N.E. Bavaria, FRG), annual time courses of chloroplast pigments in both healthy and chlorotic Norway spruce were studied. The seasonal time courses of green and appare...
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Article
Photosynthetic capacity, chloroplast pigments, and mineral content of the previous year's spruce needles with and without the new flush: analysis of the forest-decline phenomenon of needle bleaching
Spruce (Picea abies) damage in the Fichtelgebirge (FRG) occurs as needle bleaching and a depression of CO2 assimilation. Such injury may primarily result from the direct, above-ground effects of air pollution or ...