Dr Rene Van Der Wal
1987-1993 Biology study at Groningen University, the Netherlands
1993-1997 PhD: relation between vegetation succession and herbivory, Groningen University
1998-2001 Ecologist at CEH Banchory (Higher Scientific Officer)
2001-2007 Ecologist at CEH Banchory (Senior Scientific Officer)
2007-2011 Senior lecturer at Aberdeen University (within Aberdeen Centre for Environmental Sustainability)
2011-present Reader at Aberdeen University (within ACES)
René van der Wal is a senior scientist with great interest in soil-plant-herbivore interactions. His studies aim to provide innovative perspectives on ecosystem function and diversity by using a field experimental approach, connecting above and belowground ecosystem components, working at different spatial scales and integrating disciplines across the natural sciences. As many of his research questions are either influenced by or central to people, an increasing part of his work is conducted in close collaboration with social and environmental economic scientists and involves a wide range of stakeholders and/or members of the general public. Although earlier work focused largely on plant species dynamics in temperate ecosystems, his current studies take place in a wide range of ecosystems including temperate mountain, forest, moorland and island ecosystems and arctic tundra. These studies centre on the causes and consequences of ecosystem perturbations from changes in land-use, nitrogen enrichment, climate change and invasive species, thereby crosscutting traditional disciplines and trophic levels, whilst also acknowledging connectivity between terrestrial and marine or freshwater environments. He currently leads an array of studies, which involve both PhD and post-doctoral researchers, as well as bringing in specialist knowledge as a partner in larger research projects.
- Variability of Plant-herbivore-soil interactions in high-arctic Spitsbergen - Semmeldalen (since 1997)
- How grazing and nitrogen deposition impact montane moss heath - Glas Maol (since 1999)
- Seabirds, rabbits, soil foodwebs and plant species change - Isle of May (since 2003)
- Ecology and management of the non-native invasive tree mallow - Craigleith (since 2004)
EPSRC grant (Rural Digital Hub): Digital innovation and the management, use and conservation of Natural Resources www.dotrural.co.uk. Composite projects are:
- Digital conservation: Digital innovation in the promotion of volunteer interest and involvement in nature conservation programmes (in partnership with the RSPB (red kite reintroducitons) and the Bumble Bee Conservation Trust.
- wikiRivers: Exploiting digital technologies to enable effective communication of river water levels (in partnership with the Scottish Environment Projection Agency)
- MinkApp: Developing digital tools to enable large-scale community-based nature conservation action (in partnership with Rivers and Fisheries Trusts of Scotland)
- WiSE: Wildlife Smartcam for Environmental monitoring (in partnership with the James Hutton Institute and Trinity College Dublin)
NERC grant: Understanding determinants of plant invasiveness: a case study on tree mallow (post doc Louise Ross, with Hefin Jones, Cardiff University)
Effects of climate and land-use change on cuckoos (Chloe Denerley; RSPB studentship with Steve Redpath and Jerry Wilson, RSPB)
The use of digital technology in traditional landscapes' (Gina Maffey; dot.rural studentship with Mark Reed, Justin Irvine (Macaulay Institute), Steve Redpath & Chris Mellish)
Enhancing carbon sequestration through grazing management (Stuart Smith; BBSRC studentship with David Johnson, Robin Pakeman (Macaulay Institute) & Sarah Woodin.
Changes in snow lie and herbivore population regulation in an arctic Ecosystem (Helen Anderson; College of Live Sciences and Medicine studentship with Sarah Woodin, Jesper Madsen (NERI Denmark and Christiaane Huebner, Svalbard Science Forum).
Rewilding (Koen Arts, ACES studentship with A. Fischer, Macaulay Institute)
Understanding public perceptions of non-native species: values and discourses (Sebastian Selge, ACES studentship with A. Fischer, Macaulay Institute)
Currently active grants/projects
- Rural Digital Economy Research Hub (EPSRC/ESRC/AHRC/MRC grant with Farrington, Edwards et. al. (Lead of the Natural Resource Conservation theme)
- UK National Ecosystem Assessment - Lead Author of the Chapter 'Mountains, Moorlands and Heaths'
- Understanding determinants of plant invasiveness: a case study on tree mallow Lavatera arborea (NERC)
- Inclusive biodiversity management on Craigleith island: implementation of tree mallow control (SNH)
Previous grants (selected)
- Collaborative frameworks in land management: A case study on integrated deer management (RELU with J. Irvine et al.)
- Developing methodologies for assessing diffuse deer impacts in the wider countryside (SEERAD with J. Irvine et al.2008)
- Restoring biodiversity of island ecosystems; inclusive management to combat alien plant invasion (Scottish Executive; Biodiversity action grant scheme, 2005-07)
- Do herbivores decrease tundra carbon sink strength by reducing the moss layer? (NERC grant with S. Woodin, M. Sommerkorn, 2005)
- FRagility of Arctic Goose habitat: Impacts of Land use, conservation and Elevated temperatures.(FRAGILE - EU 5th framework, with Huiskes et al., 2004-06)
- Does resource partitioning maintain plant species diversity in nitrogen limited ecosystems? (NERC small grant with R. Bardgett, 2004)
- How herbivory and light mediate moss-sedge interactions (NERC grant, 2001)
- Herbivore impact on soil temperature and plant species diversity in the Arctic (NERC grant, 2000)
Currently active studentships
- See under Research activities
- Assessing the potential for recovery of degraded montane heathlands (Heather Armitage; SNH studentship with A. Britton, I. Pearce, S. Woodin, Aberdeen Univ.)
- Anthropogenic influences on carbon dynamics in peatland (Pauline Currey; ACES studentship with R. Artz, L. Dawson, D. Johnson, C. Freeman, Aberdeen Univ.)
- Ecosystem engineers of the tundra? The effects of pink footed geese on arctic ecosystem biodiversity (James Speed; NERC studentship with I.S. Jónsdóttir, S. Woodin, Aberdeen Univ.)
- Limits to tree driven changes in soil biodiversity in Scotland (Uffe Nielsen; ACES studentship with G. Osler, C. Campbell & D. Burslem, Aberdeen Univ.). Uffe currently works as a Post Doctoral Fellow at Colorado University
- The role of mosses in Arctic vegetation (Jemma Gornall; NERC studentship with S.Woodin, I Jonsdottir, Aberdeen Univ. 2002-04). Jemma currently works as Climate Impact Scientist at the Met Office, Exeter, UK
- Keystone plant species and ecosystem function: mechanisms by which trees control soil food webs (Aidan Keith; NERC studentship with G. Osler, S. Chapman, D. Burslem, Aberdeen Univ. 2004-6). Aidan currently works as Soil Scientist at CEH Lancaster
- The role of seabirds in orchestrating island food (Dan Wright; NERC studentship with R. Bardgett, Lancaster Univ. 2003-05). Dan currently works as 6th form teacher in Preston
- Understanding the mechanisms behind nitrogen deposition impacts on montane Racomitrium heath (Imogen Pearce; part-time CEH studentship with S. Woodin, Aberdeen Univ. 1999-2004)
- How soil fauna influence plant-microbial competition for N in arctic ecosystems (Stephen Dutton; NERC studentship with R. Bardgett, Lancaster Univ. 2001-02)
- Coordinator of the MSc Ecology/MRes Ecology and Environmental Sustainability programmes (with Dave Johnson)
- Coordinator of the MRes course 'Statistics for Complex Designs' (with Alex Douglas and David Lusseau)
- Coordinator of the MRes course 'Foundations of Environmental Governance' (with Ben Davies)
- Coordinator of the MRes module 'Controlled Environment Research Project'
Teaching on (only larger contributions provided):
- 1st year interdisciplinary (6th Century) course 'Sustainability'
- 3rd year course 'Plant-Animal Interactions'
Selge S, Fischer A, Van der Wal R. Public and professional views on invasive non-native species - a qualitative social scientific investigation. Biological Conservation in press.
Sjögersten S, Van der Wal R & Woodin SJ (2011). Impacts of grazing and climate warming on C pools and decomposition rates in arctic environments. Ecosystems – in press.
Armitage H, Britton A, Van der Wal R, Pearce I, Thompson D, Woodin S (2011). Nitrogen deposition enhances moss growth but leads to overall decline in habitat condition in a mountain moss-sedge heath. Global Change Biology – in press.
Dandy N, Van der Wal R (2011) Shared appreciation of woodland landscapes by land management professionals and lay people: an exploration through field-based interactive photo-elicitation. Landscape and Urban Planning 102: 43–53.
Arts K, Fischer A & Van der Wal R (2011). Wilderness: home to hazard and the promise of paradise; Exploring wilderness desire and rejection in a cultural-historical study of De Hoge Veluwe, the Netherlands. Landscape Research – in press.
Gornall JL, Woodin SJ, Jónsdóttir IS & Van der Wal R (2011) Balancing positive and negative plant interactions: how mosses structure vascular plant communities. Oecologia 166, 769-782.
Armitage HF, Britton AJ, Woodin SJ & Van der Wal R (2011) Assessing the recovery potential of alpine moss-sedge heath: Reciprocal transplants along a nitrogen deposition gradient. Environmental Pollution 159: 140-147
Currey PM, Johnson D, Dawson LA, Van der Wal R, Thornton B, Sheppard LJ, Leith ID & Artz RRE (2010) Five years of simulated atmospheric nitrogen deposition have only subtle effects on the fate of newly synthesized carbon in Calluna vulgaris and Eriophorum vaginatum. Soil Biol Biochem 16: 2307-2321.
Nielsen UN, Osler GHR, Campbell CD, Neilson R, Burslem DFRP, Van der Wal R (2010) The enigma of soil animal species diversity revisited: The role of small-scale heterogeneity. Public Library of Science One 5, e11567.
Sjögersten S, Van der Wal R, Loonen MJJE & Woodin SJ (2010) Recovery of ecosystem carbon fluxes and storage from herbivory. Biogeochemistry – in press.
Sjögersten S, Kuijper DPJ, Loonen MJJE, , Huiskes A, Van der Wal R, Woodin SJ (2010) Nitrogen transfer between herbivores and their forage species disrupted by the moss layer. Polar biology 33:1195–1203.
Speed JDM, Cooper EJ, Jónsdóttir IS, Van der Wal R, Woodin SJ (2010) Plant community properties predict vegetation resilience to herbivore disturbance in the Arctic. Journal of Ecology 98: 1002–1013.
Wright DG, Van der Wal R, Wanless S & Bardgett RD (2010) Factors affecting island food webs: the impacts of seabird nutrient enrichment and grazing on the soil food web. Soil Biol Biochem 42: 592-600.
Speed JDM, Woodin SJ, Tømmervik H, & Van der Wal R (2010) Extrapolating herbivore induced carbon loss across an arctic landscape. Polar Biology 33: 789–797.
Nielsen UN, Osler GHR, Campbell CD, Burslem DFRP & Van der Wal R (2010) The influence of vegetation type, soil properties and precipitation on the composition of soil mite and microbial communities at the landscape scale. Journal of Biogeography 37: 1317–1328.
Contributions to Journals
- Smith, SW., Robertson, AHJ., Meharg, AA., Pakeman, RJ., Johnson, D., Woodin, SJ. & Van Der Wal, R. (in press). 'Milling plant and soil material in plastic tubes over-estimates carbon and under-estimates nitrogen concentrations'. Plant and Soil.
[Online] DOI: 10.1007/s11104-013-1599-y
- Bryce, R., Van Der Wal, R., Mitchell, R. & Lambin, X. (in press). 'Metapopulation dynamics of a burrowing herbivore drive spatio-temporal dynamics of riparian plant communities'. Ecosystems.
- Armitage, HF., Britton, AJ., van der Wal, R., Pearce, ISK., Thompson, DBA. & Woodin, SJ. (2012). 'Nitrogen deposition enhances moss growth, but leads to an overall decline in habitat condition of mountain moss-sedge heath'. Global Change Biology, vol 18, no. 1, pp. 290-300.
[Online] DOI: 10.1111/j.1365-2486.2011.02493.x
- Anderson, HB., Godfrey, TG., Woodin, SJ. & van der Wal, R. (2012). 'Finding food in a highly seasonal landscape: where and how pink footed geese Anser brachyrhynchus forage during the Arctic spring'. Journal of Avian Biology, vol 43, no. 5, pp. 415-422.
[Online] DOI: 10.1111/j.1600-048X.2012.05699.x
- Armitage, HF., Britton, AJ., van der Wal, R. & Woodin, SJ. (2012). 'Grazing exclusion and phosphorus addition as potential local management options for the restoration of alpine moss-sedge heath'. Biological Conservation, vol 153, pp. 17-24.
[Online] DOI: 10.1016/j.biocon.2012.04.025
- Sjoegersten, S., van der Wal, R. & Woodin, SJ. (2012). 'Impacts of Grazing and Climate Warming on C Pools and Decomposition Rates in Arctic Environments'. Ecosystems, vol 15, no. 3, pp. 349-362.
[Online] DOI: 10.1007/s10021-011-9514-y
- Dandy, N., Ballantyne, S., Moseley, D., Gill, R., Quine, C. & Van Der Wal, R. (2012). 'Exploring beliefs behind support for and opposition to wildlife management methods: a qualitative study'. European Journal of Wildlife Research, vol 58, no. 4, pp. 695-706.
[Online] DOI: 10.1007/s10344-012-0619-1
- Arts, K., Fischer, A. & Van der Wal, R. (2012). 'The Promise of Wilderness Between Paradise and Hell: A Cultural-Historical Exploration of a Dutch National Park'. Landscape Research, vol 37, no. 3, pp. 239-256.
[Online] DOI: 10.1080/01426397.2011.589896
- Nielsen, UN., Osler, GHR., Campbell, CD., Burslem, DFRP. & van der Wal, R. (2012). 'Predictors of fine-scale spatial variation in soil mite and microbe community composition differ between biotic groups and habitats'. Pedobiologia, vol 55, no. 2, pp. 83-91.
[Online] DOI: 10.1016/j.pedobi.2011.11.002
- Arts, K., Fischer, A. & van der Wal, R. (2012). 'Common stories of reintroduction: A discourse analysis of documents supporting animal reintroductions to Scotland'. Land Use Policy, vol 29, no. 4, pp. 911-920.
[Online] DOI: 10.1016/j.landusepol.2012.01.009
- Armitage, HF., Britton, AJ., Woodin, SJ. & van der Wal, R. (2011). 'Assessing the recovery potential of alpine moss-sedge heath: Reciprocal transplants along a nitrogen deposition gradient'. Environmental Pollution, vol 159, no. 1, pp. 140-147.
[Online] DOI: 10.1016/j.envpol.2010.09.011
- Gornall, JL., Woodin, SJ., Jonsdottir, IS. & van der Wal, R. (2011). 'Balancing positive and negative plant interactions: how mosses structure vascular plant communities'. Oecologia, vol 166, no. 3, pp. 769-782.
[Online] DOI: 10.1007/s00442-011-1911-6
- Selge, S., Fischer, A. & van der Wal, R. (2011). 'Public and professional views on invasive non-native species: A qualitative social scientific investigation'. Biological Conservation, vol 144, no. 12, pp. 3089-3097.
[Online] DOI: 10.1016/j.biocon.2011.09.014
- Dandy, N. & Van der Wal, R. (2011). 'Shared appreciation of woodland landscapes by land management professionals and lay people: An exploration through field-based interactive photo-elicitation'. Landscape and Urban Planning, vol 102, no. 1, pp. 43-53.
[Online] DOI: 10.1016/j.landurbplan.2011.03.008
- Speed, JDM., Woodin, SJ., Tommervik, H. & van der Wal, R. (2010). 'Extrapolating herbivore-induced carbon loss across an arctic landscape'. Polar Biology, vol 33, no. 6, pp. 789-797.
[Online] DOI: 10.1007/s00300-009-0756-5
- Nielsen, UN., Osler, GHR., Campbell, CD., Neilson, R., Burslem, DFRP. & Van Der Wal, R. (2010). 'The Enigma of Soil Animal Species Diversity Revisited: The Role of Small-Scale Heterogeneity'. PLoS ONE, vol 5, no. 7, e11567, pp. -.
[Online] DOI: 10.1371/journal.pone.0011567
- Gornall, JL., Woodin, SJ., Jonsdottir, IS. & Van der Wal, R. (2010). 'Herbivore impacts to the moss layer determine tundra ecosystem response to grazing and warming: Erratum (vol 161, pg 747, 2009)'. Oecologia, vol 163, no. 1, pp. 277.
[Online] DOI: 10.1007/s00442-010-1603-7
- Wright, DG., van der Wal, R., Wanless, S. & Bardgett, RD. (2010). 'The influence of seabird nutrient enrichment and grazing on the structure and function of island soil food webs'. Soil Biology and Biochemistry, vol 42, no. 4, pp. 592-600.
[Online] DOI: 10.1016/j.soilbio.2009.12.008
- Keith, AM., Brooker, RW., Osler, GHR., Chapman, SJ., Burslem, DFRP. & Van Der Wal, R. (2009). 'Strong impacts of belowground tree inputs on soil nematode trophic composition'. Soil Biology and Biochemistry, vol 41, no. 6, pp. 1060-1065.
[Online] DOI: 10.1016/j.soilbio.2009.02.009
- Speed, JDM., Woodin, SJ., Tommervik, H., Tamstorf, MP. & Van Der Wal, R. (2009). 'Predicting Habitat Utilization and Extent of Ecosystem Disturbance by an Increasing Herbivore Population'. Ecosystems, vol 12, no. 3, pp. 349-359.
[Online] DOI: 10.1007/s10021-009-9227-7
- Woodin, SJ., Van Der Wal, R., Sommerkorn, M. & Gornall, JL. (2009). 'Differential allocation of carbon in mosses and grasses governs ecosystem sequestration: a 13 C tracer study in the high Arctic'. New Phytologist, vol 184, no. 4, pp. 944-949.
[Online] DOI: 10.1111/j.1469-8137.2009.03022.x
- Speed, J., Van Der Wal, R. & Woodin, SJ. (2009). 'Do nitrogen concentration and forage quality of the moss Racomitrium lanuginosum increase with latitude?'. Research Letters in Ecology.
[Online] DOI: 10.1155/2009/474627
- van der Wal, R., Fischer, A., Marquiss, M., Redpath, S. & Wanless, S. (2009). 'Is bigger necessarily better for environmental research?'. Scientometrics, vol 78, no. 2, pp. 317-322.
[Online] DOI: 10.1007/s11192-007-2017-0
- White, RM., Fischer, A., Marshall, K., Travis, JMJ., Webb, TJ., di Falco, S., Redpath, SM. & van der Wal, R. (2009). 'Developing an integrated conceptual framework to understand biodiversity conflicts'. Land Use Policy, vol 26, no. 2, pp. 242-253.
[Online] DOI: 10.1016/j.landusepol.2008.03.005
- van der Wal, R. & Hessen, DO. (2009). 'Analogous aquatic and terrestrial food webs in the high Arctic: the structuring force of a harsh climate'. Perspectives in plant ecology, evolution and systematics, vol 11, no. 3, pp. 231-240.
[Online] DOI: 10.1016/j.ppees.2009.03.003
- Post, E., Forchhammer, MC., Bret-Harte, MS., Callaghan, TV., Christensen, TR., Elberling, B., Fox, AD., Gilg, O., Hik, DS., Hoye, TT., Ims, RA., Jeppesen, E., Klein, DR., Madsen, J., McGuire, AD., Rysgaard, S., Schindler, DE., Stirling, I., Tamstorf, MP., Tyler, NJC., van der Wal, R., Welker, J., Wookey, PA., Schmidt, NM. & Aastrup, P. (2009). 'Ecological Dynamics Across the Arctic Associated with Recent Climate Change'. Science, vol 325, no. 5946, pp. 1355-1358.
[Online] DOI: 10.1126/science.1173113
- Gornall, JL., Woodin, SJ., Jonsdottir, IS. & Van der Wal, R. (2009). 'Herbivore impacts to the moss layer determine tundra ecosystem response to grazing and warming'. Oecologia, vol 161, no. 4, pp. 747-758.
[Online] DOI: 10.1007/s00442-009-1427-5
- Irvine, RJ., Fiorini, S., Yearley, S., McLeod, JE., Turner, A., Armstrong, H., White, PCL. & van der Wal, R. (2009). 'Can managers inform models? Integrating local knowledge into models of red deer habitat use'. Journal of Applied Ecology, vol 46, no. 2, pp. 344-352.
[Online] DOI: 10.1111/j.1365-2664.2009.01626.x
- Keith, AM., van der Wal, R., Brooker, RW., Osler, GHR., Chapman, SJ., Burslem, DFRP. & Elston, DA. (2008). 'Increasing litter species richness reduces variability in a terrestrial decomposer system'. Ecology, vol 89, no. 9, pp. 2657-2664.
- Sjogersten, S., van der Wal, R. & Woodin, SJ. (2008). 'Habitat type determines herbivory controls over CO 2 fluxes in a warmer Arctic'. Ecology, vol 89, no. 8, pp. 2103-2116.
[Online] DOI: 10.1890/07-1601.1
- Nielsen, UN., Osler, GHR., van der Wal, R., Campbell, CD. & Burslem, DFRP. (2008). 'Soil pore volume and the abundance of soil mites in two contrasting habitats'. Soil Biology and Biochemistry, vol 40, no. 6, pp. 1538-1541.
[Online] DOI: 10.1016/j.soilbio.2007.12.029
- van der Wal, R., Truscott, A-M, Pearce, ISK., Cole, L., Harris, MP. & Wanless, S. (2008). 'Multiple anthropogenic changes cause biodiversity loss through plant invasion'. Global Change Biology, vol 14, no. 6, pp. 1428-1436.
[Online] DOI: 10.1111/j.1365-2486.2008.01576.x
- van der Wal, R. & Palmer, SCF. (2008). 'Is breeding of farmland wading birds depressed by a combination of predator abundance and grazing?'. Biology Letters, vol 4, no. 3, pp. 256-258.
[Online] DOI: 10.1098/rsbl.2008.0012
- Pearce, I. & Van der Wal, R. (2008). 'Interpreting nitrogen pollution thresholds for sensitive habitats: The importance of concentration versus dose'. Environmental Pollution, vol 152, no. 1, pp. 253-256.
[Online] DOI: 10.1016/j.envpol.2007.04.024
- Van Der Wal, R., Sjogersten, S., Woodin, SJ., Cooper, EJ., Jonsdottir, IS., Kuijper, D., Fox, TAD. & Huiskes, AD. (2007). 'Spring feeding by pink-footed geese reduces carbon stocks and sink strength in tundra ecosystems'. Global Change Biology, vol 13, no. 2, pp. 539-545.
[Online] DOI: 10.1111/J.1365-2486.2006.01310.X
- Gornall, JL., Jónsdóttir, IS., Woodin, SJ. & Van der Wal, R. (2007). 'Arctic mosses govern below-ground environment and ecosystem processes'. Oecologia, vol 153, no. 4, pp. 931-941.
[Online] DOI: 10.1007/s00442-007-0785-0
- Keith, AM., van der Wal, R., Brooker, RW., Osler, GHR., Chapman, SJ. & Burslem, DFRP. (2006). 'Birch invasion of heather moorland increases nematode diversity and trophic complexity'. Soil Biology and Biochemistry, vol 38, pp. 3421-3430.
[Online] DOI: 10.1016/j.soilbio.2006.05.013
Chapters in Books, Reports and Conference Proceedings
- Blake, S., Siddharthan, A., Nguyen, H., Sharma, N., Robinson, A-M, O'Mahony, E., Darvill, B., Mellish, CS. & Van Der Wal, R. (2012). 'Natural Language Generation for Nature Conservation: Automating Feedback to help Volunteers identify Bumblebee Species'. in M Kay & C Boitet (eds), Proceedings of the 24th International Conference on Computational Linguistics (COLING 2012). The COLING 2012 Organizing Committee, Mumbai, pp. 311-324.
[Online] AURA: beewatch.pdf
- Siddharthan, A., Green, MJ., van Deemter, K., Mellish, CS. & Van Der Wal, R. (2012). 'Blogging birds: Generating narratives about reintroduced species to promote public engagement'. in Proceedings of the 7th International Natural Language Generation Conference (INLG 2012). ACL Anthology.
[Online] AURA: inlgKitesShort.pdf
Contributions to Conferences
- Siddharthan, A., Mellish, CS., Nguyen, H., Zeng, C., Pearce, I. & Van Der Wal, R. (2011). 'Tell me a story about the birds and the bees: Using NLG to foster public engagement in nature conservation projects'. Paper presented at Digital Engagement 2011, Newcastle, United Kingdom, 15/11/11,.
- Fairhurst, G., Van Der Wal, R., Verdicchio, F., Nazir, S. & Newey, S. (2012). 'A WIreless Smartcam Environment (WiSE)'. Third Annual Digital Economy All Hands Conference – Digital Futures, Aberdeen, United Kingdom, 23/10/12 - 25/10/12,.
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