[en] Human-driven peatland drainage has occurred in Europe for centuries, causing habitat degradation and leading to the emission of greenhouse gases. As such, in the last decades, there has been an increase in policies aiming at restoring these habitats through rewetting. Alder (Alnus glutinosa L.) is a widespread species in temperate forest peatlands with a seemingly high waterlogging tolerance. Yet, little is known about its specific response in growth and wood traits relevant for tree functioning when dealing with changing water table levels. In this study, we investigated the effects of rewetting and extreme flooding on alder growth and wood traits in a peatland forest in northern Germany. We took increment cores from several trees at a drained and a rewetted stand and analyzed changes in ring width, wood density, and xylem anatomical traits related to the hydraulic functioning, growth, and mechanical support for the period 1994–2018. This period included both the rewetting action and an extreme flooding event. We additionally used climate-growth and climate-density correlations to identify the stand-specific responses to climatic conditions. Our results showed that alder growth declined after an extreme flooding in the rewetted stand, whereas the opposite occurred in the drained stand. These changes were accompanied by changes in wood traits related to growth (i.e., number of vessels), but not in wood density and hydraulic-related traits. We found poor climate-growth and climate-density correlations, indicating that water table fluctuations have a stronger effect than climate on alder growth. Our results show detrimental effects on the growth of sudden water table changes leading to permanent waterlogging, but little implications for its wood density and hydraulic architecture. Rewetting actions should thus account for the loss of carbon allocation into wood and ensure suitable conditions for alder growth in temperate peatland forests
Abràmoff M. Magalhães P. Ram S. (2004). Image processing with IMAGEJ. Biophoton. Int. 11 36–42.
Babst F. Bouriaud O. Papale D. Gielen B. Janssens I. A. Nikinmaa E. et al. (2014). Above-ground woody carbon sequestration measured from tree rings is coherent with net ecosystem productivity at five eddy-covariance sites. New Phytol. 201 1289–1303. 10.1111/nph.12589 24206564
Ballesteros J. A. Stoffel M. Bollschweiler M. Bodoque J. M. Diez-Herrero A. (2010). Flash-flood impacts cause changes in wood anatomy of Alnus glutinosa, Fraxinus angustifolia and Quercus pyrenaica. Tree Physiol. 30 773–781. 10.1093/treephys/tpq031 20462937
Barthelmes A. (2009). Vegetation Dynamics and Carbon Sequestration of Holocene Alder (Alnus glutinosa) Carrs in NE Germany. Ph.D. dissertation. Greifswald: University of Greifswald.
Batzli J. M. Dawson J. O. (1997). Physiological and morphological responses of red alder and sitka alder to flooding. Physiol. Plant 99 653–663. 10.1111/j.1399-3054.1997.tb05369.x
Bergès L. Dupouey J.-L. Franc A. (2000). Long-term changes in wood density and radial growth of Quercus petraea Liebl. in northern France since the middle of the nineteenth century. Trees 14 398–408. 10.1007/s004680000055
Björklund J. Fonti M. V. Fonti P. den Bulcke J. V. von Arx G. (2021). Cell wall dimensions reign supreme: cell wall composition is irrelevant for the temperature signal of latewood density/blue intensity in Scots pine. Dendrochronologia 65:125785. 10.1016/j.dendro.2020.125785
Björklund J. Seftigen K. Schweingruber F. Fonti P. von Arx G. Bryukhanova M. V. et al. (2017). Cell size and wall dimensions drive distinct variability of earlywood and latewood density in Northern Hemisphere conifers. New Phytol. 216 728–740. 10.1111/nph.14639 28636081
Björklund J. von Arx G. Nievergelt D. Wilson R. Van den Bulcke J. Günther B. et al. (2019). Scientific merits and analytical challenges of tree-ring densitometry. Rev. Geophys. 57 1224–1264. 10.1029/2019RG000642
Bönsel A. (2006). Schnelle und individuenreiche Besiedlung eines revitalisierten Waldmoores durch Leucorrhinia pectoralis (Odonata: Libellulidae). Libellula 25 151–157.
Bouriaud O. Bréda N. Le Moguédec G. Nepveu G. (2004). Modelling variability of wood density in beech as affected by ring age, radial growth and climate. Trees 18 264–276. 10.1007/s00468-003-0303-x
Bouriaud O. Leban J.-M. Bert D. Deleuze C. (2005). Intra-annual variations in climate influence growth and wood density of Norway spruce. Tree Physiol. 25 651–660. 10.1093/treephys/25.6.651 15805085
Bunn A. G. (2008). A dendrochronology program library in R (dplR). Dendrochronologia 26 115–124.
Claessens H. Oosterbaan A. Savill P. Rondeux J. (2010). A review of the characteristics of black alder (Alnus glutinosa (L.) Gaertn.) and their implications for silvicultural practices. Forestry 83 163–175. 10.1093/forestry/cpp038
Cook E. R. Kairiukstis L. A. (1990). Methods of Dendrochronology. Applications in the Environmental Sciences. Dordrecht: Kluwer Academic Publishers.
Copini P. den Ouden J. Robert E. M. R. Tardif J. C. Loesberg W. A. Goudzwaard L. et al. (2016). Flood-ring formation and root development in response to experimental flooding of young Quercus robur trees. Front. Plant Sci. 7:775. 10.3389/fpls.2016.00775 27379108
Cris R. Buckmaster S. Bain C. Reed M. (2014). Global Peatland Restoration Demonstrating SUCCESS. Edinburgh: IUCN UK National Committee Peatland Programme.
Douda J. (2008). Formalized classification of the vegetation of alder carr and floodplain forests in the Czech Republic. Preslia 80 199–224.
Douda J. Čejková A. Douda K. Kochánková J. (2009). Development of alder carr after the abandonment of wet grasslands during the last 70 years. Ann. For. Sci. 66:712. 10.1051/forest/2009065
Elferts D. Dauškane I. Ûsele G. Treimane A. (2011). Effect of water level and climatic factors on the radial growth of black alder. Proc. Latvian Acad. Sci. Sect. B. Nat. Exact Appl. Sci. 65 164–169. 10.2478/v10046-011-0032-2
Franceschini T. Longuetaud F. Bontemps J.-D. Bouriaud O. Caritey B.-D. Leban J.-M. (2013). Effect of ring width, cambial age, and climatic variables on the within-ring wood density profile of Norway spruce Picea abies (L.) Karst. Trees 27 913–925. 10.1007/s00468-013-0844-6
Gill C. J. (1975). The ecological significance of adventitious rooting as a response to flooding in woody species, with special reference to Alnus glutinosa (L.) Gaertn. Flora 164 85–97. 10.1016/S0367-2530(17)31790-5
Glenz C. Schlaepfer R. Iorgulescu I. Kienast F. (2006). Flooding tolerance of Central European tree and shrub species. For. Ecol. Manag. 235 1–13. 10.1016/j.foreco.2006.05.065
Graves W. R. Kroggel M. A. Widrlechner M. P. (2002). Photosynthesis and shoot health of five birch and four alder taxa after drought and flooding. J. Environ. Hortic. 20 36–40. 10.24266/0738-2898-20.1.36
Gričar J. de Luis M. Hafner P. Levanič T. (2013). Anatomical characteristics and hydrologic signals in tree-rings of oaks (Quercus robur L.). Trees 27 1669–1680. 10.1007/s00468-013-0914-9
Hacke U. G. Sperry J. S. (2001). Functional and ecological xylem anatomy. Perspect. Plant Ecol. Evol. Syst. 4 97–115. 10.1078/1433-8319-00017
Herbst M. Eschenbach C. Kappen L. (1999). Water use in neighbouring stands of beech (Fagus sylvatica L.) and black alder (Alnus glutinosa (L.) Gaertn.). Ann. For. Sci. 56 107–120. 10.1051/forest:19990203
Joosten H. (2009). The Global Peatland CO2 Picture: Peatland Status and Drainage Associated Emissions in All Countries of the World. Wageningen: Wetlands International.
Joosten H. Sirin A. Couwenberg J. Laine J. Smith P. (2016). “The role of peatlands in climate regulation,” in Peatland Restoration and Ecosystem Services: Science, Policy and Practice Ecological Reviews, eds Bonn A. Allott T. Evans M. Joosten H. Stoneman R. (Cambridge: Cambridge University Press), 63–76. 10.1017/CBO9781139177788.005
Jurasinski G. Ahmad S. Anadon-Rosell A. Berendt J. Beyer F. Bill R. et al. (2020). from understanding to sustainable use of Peatlands: the WETSCAPES approach. Soil Syst. 4:14. 10.3390/soilsystems4010014
Kellogg R. M. Wangaard F. F. (1969). Variation in the cell-wall density of wood. Wood Fiber Sci. 1 180–204.
Kiaei M. Branch S. Naji H. R. Abdul-Hamid H. (2016). Radial variation of fiber dimensions, annual ring width, and wood density from natural and plantation trees of alder (Alnus glutinosa) wood. Wood Res. 61:10.
Kolb K. J. Sperry J. S. (1999). Differences in drought adaptation between subspecies of sagebrush (Artemisia tridentata). Ecology 80 2373–2384.
Koprowski M. Okoński B. Gričar J. Puchałka R. (2018). Streamflow as an ecological factor influencing radial growth of European ash (Fraxinus excelsior (L.)). Ecol. Indic. 85 390–399. 10.1016/j.ecolind.2017.09.051
Kozlowski T. T. (1984). “Responses of woody plants to flooding,” in Flooding and Plant Growth Physiological Ecology, ed. Kozlowski T. T. (San Diego, CA: Academic Press), 129–163. 10.1016/B978-0-12-424120-6.50009-2
Kozlowski T. T. (1997). Responses of woody plants to flooding and salinity. Tree Physiol. 17 490–490. 10.1093/treephys/17.7.490
Kozlowski T. T. (2002). Physiological-ecological impacts of flooding on riparian forest ecosystems. Wetlands 22 550–561.
Kratsch H. A. Graves W. R. (2005). Oxygen concentration affects nodule anatomy and nitrogenase activity of Alnus maritima. Plant Cell Environ. 28 688–696. 10.1111/j.1365-3040.2005.01323.x
Kreuzwieser J. Rennenberg H. (2014). Molecular and physiological responses of trees to waterlogging stress: responses of tree to waterlogging. Plant Cell Environ. 37 2245–2259. 10.1111/pce.12310 24611781
Laganis J. Pečkov A. Debeljak M. (2008). Modeling radial growth increment of black alder (Alnus glutionsa (L.) Gaertn.) tree. Ecol. Model. 215 180–189. 10.1016/j.ecolmodel.2008.02.018
Lenth L. (2020). emmeans: Estimated Marginal Means, Aka Least-Squares Means. R Package Version 1.5.2-1. Available online at: https://CRAN.R-project.org/package=emmeans (accessed May 20, 2021).
McVean D. N. (1953). Alnus Glutinosa (L.) Gaertn. J. Ecol. 41:447. 10.2307/2257070
McVean D. N. (1956). Ecology of Alnus Glutinosa (L.) Gaertn: IV. Root system. J. Ecol. 44:219. 10.2307/2257163
Müller-Westermeier G. (1995). Numerische Verfahren zu Erstellung Klimatologischer Karten. Offenbach am Main: Selbstverlag des Deutschen Wetterdienstes.
Niinemets Ü Valladares F. (2006). Tolerance to shade, drought, and waterlogging of temperate Northern Hemisphere trees and shrubs. Ecol. Monogr. 76 521–547.
Ouyang F. Ma J. An S. Wang J. Weng Y. (2018). Genetic variation of wood tracheid traits and their relationships with growth and wood density in clones of Pinus tabuliformis. J. For. Res. 29 1021–1030. 10.1007/s11676-017-0483-7
Peters R. L. Steppe K. Cuny H. E. De Pauw D. J. W. Frank D. C. Schaub M. et al. (2021). Turgor – a limiting factor for radial growth in mature conifers along an elevational gradient. New Phytol. 229 213–229. 10.1111/nph.16872 32790914
Peters R. L. von Arx G. Nievergelt D. Ibrom A. Stillhard J. Trotsiuk V. et al. (2020). Axial changes in wood functional traits have limited net effects on stem biomass increment in European beech (Fagus sylvatica). Tree Physiol. 40 498–510. 10.1093/treephys/tpaa002 32031220
Pfenninger M. Reuss F. Kiebler A. Schönnenbeck P. Caliendo C. Gerber S. et al. (2021). Genomic basis for drought resistance in European beech forests threatened by climate change. Elife 10:e65532. 10.7554/eLife.65532 34132196
Pinheiro J. Bates D. DebRoy S. Sarkar D. R Core Team (2019). nlme: Linear and Nonlinear Mixed Effects Models. R Package Version 3.1-139. Available online at: https://CRAN.R-project.org/package=nlme (accessed May 9, 2021).
Preibisch S. Saalfeld S. Tomancak P. (2009). Globally optimal stitching of tiled 3D microscopic image acquisitions. Bioinformatics 25 1463–1465.
Prendin A. L. Petit G. Carrer M. Fonti P. Björklund J. von Arx G. (2017). New research perspectives from a novel approach to quantify tracheid wall thickness. Tree Physiol. 37 976–983. 10.1093/treephys/tpx037 28379577
Pretzsch H. Biber P. Schütze G. Kemmerer J. Uhl E. (2018). Wood density reduced while wood volume growth accelerated in Central European forests since 1870. For. Ecol. Manag. 429 589–616. 10.1016/j.foreco.2018.07.045
Prieditis N. (1997). Alnus glutinosa – dominated wetland forests of the Baltic Region: community structure, syntaxonomy and conservation. Plant Ecol. 129 49–94. 10.1023/A:1009759701364
R Core Team (2020). R: A Language and Environment for Statistical Computing. Vienna: R Foundation for Statistical Computing.
Rodríguez-González P. M. Campelo F. Albuquerque A. Rivaes R. Ferreira T. Pereira J. S. (2014). Sensitivity of black alder (Alnus glutinosa [L.] Gaertn.) growth to hydrological changes in wetland forests at the rear edge of the species distribution. Plant Ecol. 215 233–245. 10.1007/s11258-013-0292-9
Rodríguez-González P. M. Stella J. C. Campelo F. Ferreira M. T. Albuquerque A. (2010). Subsidy or stress? Tree structure and growth in wetland forests along a hydrological gradient in Southern Europe. For. Ecol. Manag. 259 2015–2025. 10.1016/j.foreco.2010.02.012
Schindelin J. Arganda-Carreras I. Frise E. Kaynig V. Longair M. Pietzsch T. et al. (2012). Fiji: an open-source platform for biological-image analysis. Nat. Methods 9 676–682. 10.1038/nmeth.2019 22743772
Schmull M. Thomas F. (2000). Morphological and physiological reactions of young deciduous trees (Quercus robur L., Q. petraea [Matt.] Liebl., Fagus sylvatica L.) to waterlogging. Plant Soil 225 227–242. 10.1023/A:1026516027096
Schwieger S. Blume-Werry G. Ciesiolka F. Anadon-Rosell A. (2021). Root biomass and root traits of Alnus glutinosa show size-dependent and opposite patterns in a drained and a rewetted forest peatland. Ann. Bot. 127 337–346. 10.1093/aob/mcaa195 33211793
Tanneberger F. Appulo L. Ewert S. Lakner S. Ó Brolcháin N. Peters J. et al. (2021). The power of nature-based solutions: how Peatlands can help us to achieve key EU sustainability objectives. Adv. Sustain. Syst. 5:2000146. 10.1002/adsu.202000146
Tulik M. Grochowina A. Jura-Morawiec J. Bijak S. (2020). Groundwater level fluctuations affect the mortality of black alder (Alnus glutinosa Gaertn.). Forests 11:134. 10.3390/f11020134
Tumajer J. Treml V. (2016). Response of floodplain pedunculate oak (Quercus robur L.) tree-ring width and vessel anatomy to climatic trends and extreme hydroclimatic events. For. Ecol. Manag. 379 185–194. 10.1016/j.foreco.2016.08.013
Tyree M. Zimmerman M. (2002). Xylem Structure and the Ascent of Sap. Berlin: Springer.
van der Maaten E. van der Maaten-Theunissen M. Buras A. Scharnweber T. Simard S. Kaiser K. et al. (2015). Can we use tree rings of Black alder to reconstruct lake levels? A case study for the Mecklenburg Lake District, Northeastern Germany. PLoS One 10:e0137054. 10.1371/journal.pone.0137054 26317768
von Arx G. Carrer M. (2014). ROXAS – A new tool to build centuries-long tracheid-lumen chronologies in conifers. Dendrochronologia 32 290–293. 10.1016/j.dendro.2013.12.001
von Arx G. Kueffer C. Fonti P. (2013). Quantifying plasticity in vessel grouping – added value from the image analysis tool ROXAS. IAWA J. 34 433–445. 10.1163/22941932-00000035
Wedell S. (2020). Zeitliche und Räumliche Variabilität des Dickenwachstums in Einem Wiedervernässten Erlenbestand. Master dissertation. Greifswald: University of Greifswald.
Welch B. L. (1947). The generalization of “Student’s” problem when several different population variances are involved. Biometrika 34 28–35. 10.1093/biomet/34.1-2.28 20287819
Wickham H. (2016). ggplot2: Elegant Graphics for Data Analysis. New York, NY: Springer-Verlag.
Zang C. Biondi F. (2015). treeclim: an R package for the numerical calibration of proxy-climate relationships. Ecography 38 431–436. 10.1111/ecog.01335
Ziemińska K. Butler D. W. Gleason S. M. Wright I. J. Westoby M. (2013). Fibre wall and lumen fractions drive wood density variation across 24 Australian angiosperms. AoB PLANTS 5:lt046. 10.1093/aobpla/plt046
Zoltai S. C. Martikainen P. J. (1996). “Estimated extent of forested peatlands and their role in the global carbon cycle,” in Forest Ecosystems, Forest Management and the Global Carbon Cycle, eds Apps M. J. Price D. T. (Berlin: Springer Berlin Heidelberg), 47–58. 10.1007/978-3-642-61111-7_5
Zuur A. F. Ieno E. N. Elphick C. S. (2010). A protocol for data exploration to avoid common statistical problems. Methods Ecol. Evol. 1 3–14. 10.1111/j.2041-210X.2009.00001.x