TY - JOUR A1 - Dobbertin, Matthias A1 - Eilmann, Britta A1 - Bleuler, Peter A1 - Giuggiola, Arnaud A1 - Graf Pannatier, Elisabeth A1 - Landolt, Werner A1 - Schleppi, Patrick A1 - Rigling, Andreas T1 - Effect of irrigation on needle morphology, shoot and stem growth in a drought-exposed Pinus sylvestris forest JF - Tree Physiology N2 - In Valais, Switzerland, Scots pines (Pinus sylvestris L.) are declining, mainly following drought. To assess the impact of drought on tree growth and survival, an irrigation experiment was initiated in 2003 in a mature pine forest, approximately doubling the annual precipitation. Tree crown transparency (lack of foliage) and leaf area index (LAI) were annually assessed. Seven irrigated and six control trees were felled in 2006, and needles, stem discs and branches were taken for growth analysis. Irrigation in 2004 and 2005, both with below-average precipitation, increased needle size, area and mass, stem growth and, with a 1-year delay, shoot length. This led to a relative decrease in tree crown transparency (−14%) and to an increase in stand LAI (+20%). Irrigation increased needle length by 70%, shoot length by 100% and ring width by 120%, regardless of crown transparency. Crown transparency correlated positively with mean needle size, shoot length and ring width and negatively with specific leaf area. Trees with high crown transparency (low growth, short needles) experienced similar increases in needle mass and growth with irrigation than trees with low transparency (high growth, long needles), indicating that seemingly declining trees were able to ‘recover’ when water supply became sufficient. A simple drought index before and during the irrigation explained most of the variation found in the parameters for both irrigated and control trees. Y1 - 2010 U6 - http://dx.doi.org/10.1093/treephys/tpp123 SN - 1758-4469 (Online) SN - 0829-318X (Print) VL - 30 IS - 3 SP - 346 EP - 360 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Egli, Simon A1 - Ayer, François A1 - Peter, Martina A1 - Eilmann, Britta A1 - Rigling, Andreas T1 - Is forest mushroom productivity driven by tree growth? Results from a thinning experiment JF - Annals of Forest Science N2 - • Most of the edible forest mushrooms are mycorrhizal and depend on carbohydrates produced by the associated trees. Fruiting patterns of these fungi are not yet fully understood since climatic factors alone do not completely explain mushroom occurrence. • The objective of this study was to retrospectively find out if changing tree growth following an increment thinning has influenced the diversity patterns and productivity of associated forest mushrooms in the fungus reserve La Chanéaz, Switzerland. • The results reveal a clear temporal relationship between the thinning, the growth reaction of trees and the reaction of the fungal community, especially for the ectomycorrhizal species. The tree-ring width of the formerly suppressed beech trees and the fruit body number increased after thinning, leading to a significantly positive correlation between fruit body numbers and tree-ring width. • Fruit body production was influenced by previous annual tree growth, the best accordance was found between fruit body production and the tree-ring width two years previously. • The results support the hypothesis that ectomycorrhizal fruit body production must be linked with the growth of the associated host trees. Moreover, the findings indicate the importance of including mycorrhizal fungi as important players when discussing a tree as a carbon source or sink. Y1 - 2010 U6 - http://dx.doi.org/10.1051/forest/2010011 SN - 1286-4560 (Print) SN - 1297-966X (Online) VL - 67 IS - 5 SP - 509 PB - Springer CY - Paris ER - TY - JOUR A1 - Eilmann, Britta A1 - Buchmann, Nina A1 - Siegwolf, Rolf A1 - Saurer, Matthias A1 - Cherubini, Paolo A1 - Rigling, Andreas T1 - Fast response of Scots pine to improved water availability reflected in tree-ring width and δ13C JF - Plant, Cell and Environment N2 - Drought-induced forest decline, like the Scots pine mortality in inner-Alpine valleys, will gain in importance as the frequency and severity of drought events are expected to increase. To understand how chronic drought affects tree growth and tree-ring δ13C values, we studied mature Scots pine in an irrigation experiment in an inner-Alpine valley. Tree growth and isotope analyses were carried out at the annual and seasonal scale. At the seasonal scale, maximum δ13C values were measured after the hottest and driest period of the year, and were associated with decreasing growth rates. Inter-annual δ13C values in early- and latewood showed a strong correlation with annual climatic conditions and an immediate decrease as a response to irrigation. This indicates a tight coupling between wood formation and the freshly produced assimilates for trees exposed to chronic drought. This rapid appearance of the isotopic signal is a strong indication for an immediate and direct transfer of newly synthesized assimilates for biomass production. The fast appearance and the distinct isotopic signal suggest a low availability of old stored carbohydrates. If this was a sign for C-storage depletion, an increasing mortality could be expected when stressors increase the need for carbohydrate for defence, repair or regeneration. Y1 - 2010 U6 - http://dx.doi.org/10.1111/j.1365-3040.2010.02153.x SN - 1365-3040 (Online) SN - 0140-7791 (Print) VL - 33 IS - 8 SP - 1351 EP - 1360 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Eilmann, Britta A1 - Dobbertin, Matthias A1 - Rigling, Andreas T1 - Growth response of Scots pine with different crown transparency status to drought release JF - Annals of Forest Science Y1 - 2013 U6 - http://dx.doi.org/10.1007/s13595-013-0310-z SN - 1286-4560 (Print) SN - 1297-966X (Online) VL - 70 IS - 7 SP - 685 EP - 693 PB - Springer CY - Cham ER - TY - JOUR A1 - Eilmann, Britta A1 - Rigling, Andreas ED - Abrams, Marc T1 - Tree-growth analyses to estimate tree species' drought tolerance JF - Tree Physiology N2 - Climate change is challenging forestry management and practices. Among other things, tree species with the ability to cope with more extreme climate conditions have to be identified. However, while environmental factors may severely limit tree growth or even cause tree death, assessing a tree species' potential for surviving future aggravated environmental conditions is rather demanding. The aim of this study was to find a tree-ring-based method suitable for identifying very drought-tolerant species, particularly potential substitute species for Scots pine (Pinus sylvestris L.) in Valais. In this inner-Alpine valley, Scots pine used to be the dominating species for dry forests, but today it suffers from high drought-induced mortality. We investigate the growth response of two native tree species, Scots pine and European larch (Larix decidua Mill.), and two non-native species, black pine (Pinus nigra Arnold) and Douglas fir (Pseudotsuga menziesii Mirb. var. menziesii), to drought. This involved analysing how the radial increment of these species responded to increasing water shortage (abandonment of irrigation) and to increasingly frequent drought years. Black pine and Douglas fir are able to cope with drought better than Scots pine and larch, as they show relatively high radial growth even after irrigation has been stopped and a plastic growth response to drought years. European larch does not seem to be able to cope with these dry conditions as it lacks the ability to recover from drought years. The analysis of trees' short-term response to extreme climate events seems to be the most promising and suitable method for detecting how tolerant a tree species is towards drought. However, combining all the methods used in this study provides a complete picture of how water shortage could limit species. Y1 - 2012 U6 - http://dx.doi.org/10.1093/treephys/tps004 SN - 0829-318X (Print) SN - 1758-4469 (Online) VL - 32 IS - 2 SP - 178 EP - 187 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Eilmann, Britta A1 - Weber, Pascale A1 - Rigling, Andreas A1 - Eckstein, Dieter T1 - Growth reactions of Pinus sylvestris L. and Quercus pubescens Willd. to drought years at a xeric site in Valais, Switzerland JF - Dendrochronologia Y1 - 2006 U6 - http://dx.doi.org/doi:10.1016/j.dendro.2005.10.002 SN - 1612-0051 (Online) SN - 1125-7865 (Print) VL - 23 IS - 3 SP - 121 EP - 132 ER - TY - JOUR A1 - Eilmann, Britta A1 - Zweifel, Roman A1 - Buchmann, Nina A1 - Fonti, Patrick A1 - Rigling, Andreas T1 - Drought-induced adaptation of the xylem in Scots pine and pubescent oak JF - Tree Physiology Y1 - 2009 U6 - http://dx.doi.org/10.1093/treephys/tpp035 SN - 0829-318X (Print) SN - 1758-4469 (Online) VL - 29 IS - 8 SP - 1011 EP - 1020 PB - Heron CY - Victoria, BC ER - TY - JOUR A1 - Eilmann, Britta A1 - Zweifel, Roman A1 - Buchmann, Nina A1 - Graf Pannatier, Elisabeth A1 - Rigling, Andreas T1 - Drought alters timing, quantity, and quality of wood formation in Scots pine JF - Journal of Experimental Botany Y1 - 2011 U6 - http://dx.doi.org/10.1093/jxb/erq443 SN - 1460-2431 (Online) SN - 0022-0957 (Print) VL - 62 IS - 8 SP - 2763 EP - 2771 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Feichtinger, Linda M. A1 - Eilmann, Britta A1 - Buchmann, Nina A1 - Rigling, Andreas T1 - Growth adjustments of conifers to drought and to century-long irrigation JF - Forest Ecology and Management N2 - Our knowledge on tree responses to drought is mainly based on short-term manipulation experiments which do not capture any possible long-term adjustments in this response. Therefore, historical water channels in inner-Alpine dry valleys were used as century-long irrigation experiments to investigate adjustments in tree growth to contrasting water supply. This involved quantifying the tree-ring growth of irrigated and non-irrigated (control) Scots pine (Pinus sylvestris L.) in Valais (Switzerland), as well as European larch (Larix decidua Mill.) and black pine (Pinus nigra Arnold) in Vinschgau (Italy). Furthermore, the adjustments in radial growth of Scots pine and European larch to an abrupt stop in irrigation were analyzed. Irrigation promoted the radial growth of all tree species investigated compared to the control: (1) directly through increased soil water availability, and (2) indirectly through increased soil nutrients and humus contents in the irrigated plots. Irrigation led to a full elimination of growth responses to climate for European larch and black pine, but not for Scots pine, which might become more sensitive to drought with increasing tree size in Valais. For the control trees, the response of the latewood increment to water availability in July/August has decreased in recent decades for all species, but increased in May for Scots pine only. The sudden irrigation stop caused a drop in radial growth to a lower level for Scots pine or similar level for larch compared to the control for up to ten years. However, both tree species were then able to adjust to the new conditions and subsequently grew with similar (Scots pine) or even higher growth rates (larch) than the control. To estimate the impact of climate change on future forest development, the duration of manipulation experiments should be on longer time scales in order to capture adjustment processes and feedback mechanisms of forest ecosystems. Y1 - 2014 U6 - http://dx.doi.org/10.1016/j.foreco.2014.08.008 SN - 1872-7042 (Online) SN - 0378-1127 (Print) VL - 2014 IS - 334 SP - 96 EP - 105 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Feichtinger, Linda M. A1 - Eilmann, Britta A1 - Buchmann, Nina A1 - Rigling, Andreas T1 - Trait-specific responses of Scots pine to irrigation on a short vs long time scale JF - Tree Physiology Y1 - 2015 U6 - http://dx.doi.org/10.1093/treephys/tpu114 SN - 1758-4469 (Online) SN - 0829-318X (Print) N1 - Ab 12 Monaten nach Veröffentlichung kostenfrei zugänglich. VL - 35 IS - 00 SP - 1 EP - 12 PB - Heron CY - Victoria, BC ER -