Microhabitat diversity of ancient trees in Hyrcanian Old-Growth Forests, Iran
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Abstract. Veysi Z, Pour MJ, Etemad V. 2025. Microhabitat diversity of ancient trees in Hyrcanian Old-Growth Forests, Iran. Biodiversitas 26: 6523-6540. Old-growth forests play a critical role in maintaining biodiversity by supporting diverse Tree-related Microhabitats (TreMs), yet their distribution patterns in Iran’s Hyrcanian Old-Growth Forests remain understudied. This study presents the first systematic assessment of TreMs in temperate old-growth forests of northern Iran, focusing on 60 ancient trees across four key species: Oriental beech (Fagus orientalis), velvet maple (Acer velutinum), alder (Alnus subcordata), and hornbeam (Carpinus betulus) in Kheyrud Forest. We identified and analyzed 12 distinct TreM types, including cavities, deadwood, and epiphytes, and evaluated their spatial distribution using GIS alongside environmental variables (elevation, slope, stand structure). Our results demonstrate that velvet maple and beech trees host the highest TreM richness, functioning as keystone structures for habitat heterogeneity. Notably, velvet maple (A. velutinum) showed strong associations with woodpecker cavities, reflecting species-specific microhabitat relationships. Statistical analyses revealed significant variation in TreM distribution across tree species and forest types, emphasizing the importance of preserving diverse tree assemblages to sustain microhabitat complexity. These findings provide actionable insights for conserving the Hyrcanian Old-Growth Forests, a UNESCO-listed biodiversity hotspot, and highlight the global relevance of protecting old-growth ecosystems for biodiversity resilience. By linking TreM patterns to forest structure and environmental gradients, this study establishes a foundation for evidence-based management strategies in temperate forests worldwide.
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References
Alavi S, Veiskarami R, Esmailzadeh O, Gadow KV. 2020. Analyzing the biological and structural diversity of Hyrcanian Old-Growth Forests dominated by Taxus baccata L. Diversity 12 (6): 240. DOI: 10.3390/d12060240.
Asbeck T, Grobmann J, Paillet Y, Winiger N, Bauhus, J. 2021. The use of tree-related microhabitats as forest biodiversity indicators and to guide integrated forest management. Curr For Rep 7: 59-68. DOI: 10.1007/s40725-020-00132-5.
Augustin N, Alphonse N, Jean CT, van der Yntze H. 2021. Density and characteristics of tree cavities inside and outside Volcanoes National Park, Rwanda. Biodivers Conserv 28 (13): 3597-3620.
Azaryan M, Marvie Mohadjer M.R, Etemaad V, Shirvany A, Sadeghi SMM. 2015. Morphological characteristics of old trees in Hyrcanian Old-Growth Forests (Case study: Pattom and Namkhaneh districts, Kheyrud). For Wood Prod 68 (1): 47-59. DOI: 10.22059/JFWP.2015.53977.
Bobiec A. Jaszcz E, Wojtunik K. 2011. Oak (Quercus robur L.) regeneration as a response to natural dynamics of stands in European hemiboreal zone. Eur J For Res 130: 785-797. DOI: 10.1007/s10342-010-0471-3.
Bütler R, Lachat, T, Krumm F, Kraus D, Larrieu L. 2021. Know, Protect and Promote Habitat Trees. WSL Fact Sheet, Swiss Federal Institute, Birmensdorf, Switzerland.
Cockle KL, Martin K, Wesołowski T. 2011. Woodpeckers, decay, and the future of cavity-nesting vertebrate communities worldwide. Front Ecol Environ 9 (7): 377-382. DOI: 10.1890/110013.
Finsinger W, Cagliero E, Morresi D, Paradis L, Curovic M, Garbarino M, Marchi M, Meloni F, Spalevic V, Lingua N, Motta R. 2022. The value of long-term history of small and fragmented old-growth forests for restoration ecology. Past Glob Changes Mag 30 (1): 8-9. DOI: 10.22498/pages.30.1.8.
Franc N, Au-Yeung C, Goethem EV, Silva E. 2007. SCF ubiquitin ligase complex mediates phagocytosis through the novel F-box domain protein, Pallbearer. Ann Dros Res Conf 48: 753C.
Gilhen-Baker M, Roviello V, Beresford-Kroeger D, Roviello J. 2022. Old growth forests and large old trees as critical organisms connecting ecosystems and human health. A review. Environ Chem Lett 20: 1529-1538. DOI: 10.1007/s10311-021-01372-y.
Hafizy E, Goring S. 2021. Four millennia of vegetation and environmental history above the Hyrcanian forest, Northern Iran. Veg Hist Archaeobot 30: 611-627. DOI: 10.1007/s00334-020-00813-y.
Haghighatdoust A, Waez-Mousavi SM. 2021. Frequency of tree micro-habitats in Persian ironwood- hornbeam forest at Bahramnia forestry plan (Gorgan). J Wood For Sci Technol 27 (4): 113-129. DOI: 10.22069/jwfst.2021.18045.1874.
Javanmiri PM, Etemad V, Sooofi MH. 2022. Some structural features of forest types in Hyrcanian Old-Growth Forests (A case study: Palang-Darreh forest, Savadkoh). J Plant Res 35 (1): 47-67. DOI: 20.1001.1.23832592.1401.35.1.14.8.
Javanmiri PM, Etemad V. 2024. Habitat trees in mixed stands and mid-altitude elevation in Hyrcanian Old-Growth Forests (Case study: Kheyrud forest, Nowshahr). Iranian J For Poplar Res 32 (1): 29-45. DOI: 10.22092/IJFPR.2023.363743.2122.
Krebs C.J. 1999. Ecological Methodology 2nd Edition. Benjamin Cummings, Menlo Park.
Kulla L, Roessiger J, Bošeľa M, Kucbel S, Murgaš V, Vencurik J, Pittner J, Jaloviar P, Šumichrast L, Saniga M. 2023. Changing patterns of natural dynamics in old-growth European beech (Fagus sylvatica L.) forests can inspire forest management in Central Europe. For Ecol Manag 529: 120633. DOI: 10.1016/j.foreco.2022.120633.
Larrieu L, Bouget C, Courbaud B, Doerfler I, Gouix N, Goulard M, Ladet S, Laroche F, Acloque A, Bütler R, Kozák D, Kraus D, Krumm F, Lachat T, Martin M, Müller J, Paillet Y, Schuck A, Stillhard J, Zudin S. 2024. Spatial distribution of tree-related microhabitats in European beech-dominated forests. Biol Conserv 301: 110867. DOI: 10.1016/j.biocon.2024.110867.
Larrieu L, Cateau E. 2016. Development of tree-related microhabitats in beech (Fagus sylvatica L.) forests with contrasting management histories in the French Pyrenees. Eur J For Res 135: 423-438.
Larrieu L, Paillet Y, Winter S, Bütler R, Kraus D, Krumm F, Lachat T, Michel AK, Regnery B, Vandekerkhove K. 2018. Tree related microhabitats in temperate and Mediterranean European forests: A hierarchical typology for inventory standardization. Ecol Indic 84: 194-207. DOI: 10.1016/j.ecolind.2017.08.051.
Lindenmayer DB, Laurance WF. 2017. The ecology, distribution, conservation and management of large old trees. Biol Rev 92 (3): 1434-1458. DOI: 10.1111/brv.12290.
MacArthur R, MacArthur J. 1961. On Bird Species Diversity. Ecology 42 (3): 594-598. DOI: 10.2307/1932254.
Marthy W, Gorska M. 2024. Ancient trees are essential elements for high-mountain forest conservation: Linking the longevity of trees to their ecological function. Proc Natl Acad Sci 121 (7): e2317866121. DOI: 10.1073/pnas.2317866121.
Marziliano PA, Antonucci S, Tognetti R, Marchetti M, Chirici G, Corona P, Lombardi F. 2021. Factors affecting the quantity and type of tree-related microhabitats in Mediterranean mountain forests of high nature value. iForest 14: 250-259. DOI: 10.3832/ifor3568-014.
Maxence M, Fenton N, Morin H. 2021. Tree-related microhabitats and deadwood dynamics form a diverse and constantly changing mosaic of habitats in boreal old-growth forests. For Ecol Manag 488: 118973. DOI: 10.1016/j.foreco.2021.118973.
Nordén B, Appelqvist T. 2001. Conceptual problems of ecological continuity and its bioindicators. Biodivers Conserv 10: 779-79. DOI: 10.1023/A:1016675103935.
Nuber R, Bianco G, Kraus D, Larrieu L, Feldhaar H, Schleuning M, Müller J. 2024. An adapted typology of tree-related microhabitats including tropical forests. Ecol Indic 167: 112690. DOI: 10.1016/j.ecolind.2024.112690.
Paillet Y, Bergès L, Hjältén J, Odor P, Avon C, Bernhardt-Römermann M, Bijlsma R-J, De Bruyn L, Fuhr M, Grandin U, Kanka R, Lundin L, Luque S, Magura T, Matesanz S, Mészáros I, Sebastia M-T, Schmidt W, Standovar T, Tothmeresz B, Uotila A, Vallardes F, Vellak K, Virtanen R. 2010. Biodiversity differences between managed and unmanaged forests: Meta-analysis of species richness in Europe. Conserv Biol 24 (1): 101-112. DOI: 10.1111/j.1523-1739.2009.01399.x.
Palik B, D’Amato A, Franklin J, Johnson K. 2021. Ecological Silviculture Foundations and Applications. Waveland Press, Illinois.
Przepióra F, Ciach M. 2022. Tree microhabitats in natural temperate riparian forests: An ultra-rich biological complex in a globally vanishing habitat. Sci Total Environ 806: 150792. DOI: 10.1016/j.scitotenv.2021.150792.
Przepióra F, Ciach M. 2023. Profile of tree-related microhabitats in the primeval Białowieża Forest: A benchmark for temperate woodlands. Sci Total Environ 905: 167273. DOI: 10.1016/j.scitotenv.2023.167273.
Przepióra F, Ciach M. 2025. Bark beetles as ecosystem engineers: Triggered tree mortality rearranges the assemblage of tree-related microhabitats in old-growth coniferous forest. For Ecol Manag 596: 123084. Doi: 10.1016/j.foreco.2025.123084.
Rahmani M, Bayat M. 2023. Landscape variation in tree species richness in Northern Iran forests: Implications for old-growth conservation. J For Ecol Manag 521: 120379. DOI: 10.1016/j.foreco.2023.120379.
Ramezani E, De Klerk P, Naqinezhad A, Theuerkauf M, Joosten H. 2023. Long-term dynamics of Oriental beech (Fagus orientalis Lipsky) stands in the Hyrcanian Old-Growth Forests of Northern Iran. Rev Palaeobot Palynol 312: 104871. DOI: 10.1016/j.revpalbo.2023.104871.
Ranius T, Hämäläinen A, Sjögren J, Hiron M, Jonson D, Kubart A, Schroeder M, Dahlberg A, Thor J, Jonsell M. 2019. The evolutionary species pool concept does not explain occurrence patterns of dead-wood-dependent organisms: Implications for logging residue extraction. Oecologia 191: 241-252. DOI: 10.1007/s00442-019-04473-2.
Regnery B, Paillet Y, Couvet D. Kerbiriou CH. 2013. Which factors influence the occurrence and density of tree microhabitats in Mediterranean oak forests? For Ecol Manag 295: 118-125. DOI: 10.1016/j.foreco.2013.01.009.
Runnel K, Lohmus A. 2017. Deadwood-rich managed forests provide insights into the old-forest association of wood-inhabiting fungi. Fungal Ecol 27: 155-167. DOI: 10.1016/j.funeco.2016.09.006.
Spınu A, Nicolaie M, Asbeck T, Kozak D, Paillet Y, Cateau E, Mikola M, Svoboda M, Bauhus J. 2024. Temporal development of microhabitats on living habitat trees in temperate European forests. Ecosystems 27: 690-709. DOI: 10.1007/s10021-024-00915-y.
Stokland N, Siitonen J, Gonsson BG. 2012. Biodiversity in Dead Wood. Cambridge University Press, Cambridge. DOI: 10.1017/CBO9781139025843.
van 't Padje A, Klein M, Caldas V, Oyarte GL, Broersma C, Hoebe N, Sanders IR, Shimizu T, Kiers ET. 2022. Decreasing relatedness among mycorrhizal fungi in a shared plant network increases fungal network size but not plant benefit. Ecol Lett 25 (2): 509-520. DOI: 10.1111/ele.13947.
Winter S, Götz M, Jansen F. 2022. Tree-related microhabitats: A comparison of managed and unmanaged oriental beech-dominated forests in Northern Iran. Front For Glob Change 5: 818474. DOI: 10.3389/ffgc.2022.818474.
Wirth C, Winter S, Mokany K. 2025. Rewilding beech-dominated temperate forest ecosystems: Effects on tree microhabitat dynamics and biodiversity recovery. iForest 18: 175-186. DOI: 10.3832/ifor4600-017.