Tree species from two contrasting habitats for use in harsh urban environments respond differently to extreme drought
- 130 Downloads
The role of trees in city cooling has warranted much attention based on concerns over climate change and urban expansion. Simultaneously, there is an interest in introducing species from dry habitats to cope with the increasing risks of drought under climate change. The general understanding is that the evolutionary adaptation to respective resource supplies in species’ habitats affects their environmental tolerance. The physical performances of six frequently planted species, originating from two contrasting habitats, were tested in a drought experiment. We (1) investigated if species from drier habitats are more drought tolerant than species that have evolved in Central European woodlands under a temperate climate regime and (2) discussed the effect of tolerance on the cooling potential of these trees. Native species from mesic habitats maintained only 48% of their controls sap flux and of these species, Tilia cordata had the worst performance with premature leaf senescence. Species from drier habitats had less reduction in sap flux (60%) but lower stem growth, possibly favouring (fine) root development into deeper soil layers, as observed when comparing linden species. Higher stem water exploitation and stronger regulation of water use at high evaporative demand were further reaction patterns that likely helped species from dry habitats maintain good physiological functions. Therefore, even under sustained drought, we expect them to have a higher cooling capacity. As a conclusion, they should be favoured for planting in extreme urban environments. Systematic screening and testing of promising species from target habitats is recommended to diversify the choice of species.
KeywordsClimate change Cooling effects Drought tolerance Sap flux density Resistance Urban trees
We thank the heads and staff members of the municipal nursery of Munich-Laim for their support and encouragement to conduct our field study there. The authors would also like to express their gratitude to Felix Seebauer and Jonas Schweiger for their assistance in field data collection. This work was supported by the Bavarian State Ministry of Education, Cultural Affairs, Science and Arts, Munich, Germany [VIII.2-F1116.WE].
Compliance with ethical standards
The experiments comply with the current laws of Germany.
Conflict of interest
The authors declare that they have no conflict of interest.
- Armson D (2012) The effect of trees and grass on the thermal and hydrological performance of an urban area dissertation, University of ManchesterGoogle Scholar
- BBCH (2001) Entwicklungsstadien mono- und dikotyler Pflanzen. BBCH Monografie. https://doi.org/10.5073/bbch0514
- Choat B, Jansen S, Brodribb TJ, Cochard H, Delzon S, Bhaskar R, Bucci SJ, Field TS, Gleason SM, Hacke UG, Jacobsen AL, Lens F, Maherali H, Martínez-Vilalta J, Mayr S, Mencuccini M, Mitchell PJ, Nardini A, Pittermann J, Pratt RB, Sperry JS, Westoby M, Wright IJ, Zanne AE (2012) Global convergence in the vulnerability of forests to drought. Nature 491:752–755. https://doi.org/10.1038/nature11688 CrossRefGoogle Scholar
- Duhme F, Pauleit S (2000) The dendrofloristic richness of SE-Europe, a phenomenal treasure for urban plantings. Mitteilungen aus der Biologischen Bundesanstalt für Land- und Forstwirtschaft Berlin-Dahlem 370:23–29Google Scholar
- DWD (2018) www.dwd.de. Accessed 15 March 2018
- Esri (2014) ArcGISGoogle Scholar
- Fini A, Ferrini F, Frangi P, Amoroso G, Piatti R (2009) Withholding irrigation during the establishment phase affected growth and physiology of Norway maple (Acer platanoides) and linden (Tilia spp.). Arboricult Urban For 35:241–251Google Scholar
- GALK (2018) GALK-Straßenbaumtest 1 and 2. www.galk.de. Accessed 01 March 2018
- Hiemstra JA (2011) Straßenbaumtest in den Niederlanden. Veitshöchheimer Berichte 152:37–41Google Scholar
- Kiermeier P (1995) Die Lebensbereiche der Gehölze eingeteilt nach dem Kennziffernsystem. PinnebergGoogle Scholar
- Köhler M (2010) Cacao agroforestry under ambient and reduced throughfall – tree water use characteristics and stand water budgeting. Dissertation, University of GöttingenGoogle Scholar
- Larcher W (2001) Ökophysiologie der Pflanzen. Ulmer Verlag, StuttgartGoogle Scholar
- LWG (2018) Forschungsprojekt Stadtgrün 2021. Neue Bäume braucht das Land. www.lwg.bayern.de. Accessed 26 April 2018
- Moser A, Rahman MA, Pretzsch H, Pauleit S, Rötzer T (2017) Inter- and intraannual growth patterns of urban small-leaved lime (Tilia cordata mill.) at two public squares with contrasting microclimatic conditions. Int J Biometeorol 61:1095–1107. https://doi.org/10.1007/s00484-016-1290-0 CrossRefGoogle Scholar
- Niinemets Ü, Valladares F (2006) Tolerance to shade, drought, and water logging of temperate northern hemisphere trees and shrubs. Ecol Monogr 76:521–547. https://doi.org/10.1890/0012-9615(2006)076[0521:TTSDAW]2.0.CO;2Google Scholar
- R Core Team (2014) R: A language and environment for statistical computingGoogle Scholar
- Roloff A (2013) Stadt- und Straßenbäume der Zukunft – Welche Arten sind geeignet? Aktuelle Fragen der Stadtbaumplanung, -pflege und -verwendung, Forstwissenschaftliche Beiträge Tharandt Beiheft 14:173–187Google Scholar
- Roloff A, Bärtels A (2006) Flora Der Gehölze – Bestimmung, Eigenschaften Verwendung. Ulmer Verlag, StuttgartGoogle Scholar
- Roloff A, Grundmann B, Korn S (2013) Trockenstress-Toleranz bei Stadtbäumen – Anpassungs- und Schutzstrategien/Arteneignung. In: Dujesiefken D (ed) Jahrbuch der Baumpflege, 2013. Haymarket Media, Braunschweig, pp 173–185Google Scholar
- Sjöman H, Gunnarsson A, Pauleit S, von Bothmer R (2012) Selection approach of urban trees for inner-city environments: learning from nature. Arboricult Urban For 38:194–204Google Scholar