Uffe joined HIE in 2011 from the Department of Biology and Natural Resource Ecology Laboratory, Colorado State University, USA, where he worked as a Research Scientist with Professor Diana H. Wall.
Uffe received his PhD in 2008 from University of Aberdeen, Scotland, in close collaboration with the Macaulay Institute (now the James Hutton Institute) and Center of Hydrology and Biology (CEH). His PhD research focused on the distribution and community composition of soil biota (microbes and soil mites in particular) across various spatial scales in two contrasting habitats. This research mainly targeted the questions of what structures belowground communities and how belowground communities respond to environment parameters and environmental changes (such as land use and climate).
Through his research at CSU Uffe continued investigating patterns of, and mechanisms underlying, biodiversity and community composition belowground, whilst also trying to establish and quantify potential links between soil biodiversity and belowground community composition and ecosystem processes/functioning and ecosystem services.
His position here also allowed him to expanded his research to include a more broad range of soil biota and explore the flow of C and N through the soil food web using stable isotope techniques.
Areas of Research / Teaching Expertise
Uffe is broadly interested in community and ecosystem ecology, and the link between the two, i.e. how do changes in one influence the other.
In a time where large-scale changes in land use and climate are impacting ecosystems across the globe it is essential for human well-being to acquire knowledge of the potential implications of these changes. For instance, species gains and losses, and changes in community composition, belowground due to climate changes can impact nutrient cycling, which may lead to changes in aboveground communities and potentially limit productivity of agricultural lands.
Other research areas of interest to Uffe include large-scale ecological theories, whether ecological theories hold across ecosystem types (including soils) and scales, drivers of species richness and biogeography (of soil biota in particular) etc.
Over the past few years Uffe has used the biologically simple soils of the McMurdo Dry Valleys, East Antarctica, to explore these aspects of ecology. While he will continue his Antarctic research through collaboration with the Australian Antarctic Division as well as the USA McMurdo Long Term Ecological Research program he will explore whether the hypotheses gained through this research are applicable in more biologically complex systems.
Motivated students are encouraged to contact Dr Nielsen to discuss potential undergraduate and graduate research projects broadly related to soil ecology and above-belowground interactions.
Awards and Recognition
- Section editor for Nature Knowledge (Community Ecology) (opens in a new window);
- Subject editor for Ecosphere (opens in a new window);
- Reviewer for several international journals including: Biology Letters; Ecosystems; Global Change Biology; Nature Knowledge; Oecologia; Plant and Soil; PLoS ONE; Soil Biology & Biochemistry
Selected Research Images
Soils are highly diverse systems. All the fauna shown here was extracted using Tullgren funnels (dry extraction) from a single soil core collected in a birch woodland, Scotland, measuring 3.5 cm diameter and 5 cm depth. This method only samples the fauna that live in the airfilled pores within the soil also known as microarthropods. It is not unusual to find several hundreds of thousands individuals representing hundreds of species in one m2 soil. If we used a different wet extraction method the soils would reveal a further astonishing diversity of mesofauna dominated by the nematodes (with abundances measured in the millions per m2). All these organisms combined have a large impact on the soil food web, and they represent a multitude of life styles ranging from plant parasites to predators. While our knowledge of these organisms is accumulating we still need a better understanding of how they influence key processes, such as decomposition and the release of nutrients for plants, and how the communities will respond to land management and potential climate change scenarios to better protect and conserve the benefits we receive from soils.
Project Bluestem at the Konza Long-Term Ecological Research site, Kansas, USA. This project uses dual stable isotope (13C and 15N) labelled big bluestem litter to investigate how carbon and nitrogen flows through the soil food web and how large a role soil fauna play in the decomposition process. Dr. Nielsen is a collaborator on the project with the principal investigator, Prof Francesca Cotrufo, and the co-investigators, Profs Diana Wall and Bill Parton, all based at Natural Resource Ecology Lab at Colorado State University.
Taylor Valley, McMurdo Dry Valleys, East Antarctica. While a large part of Antarctica is ice or snow covered some areas, like the McMurdo Dry Valleys, are ice and snow free all year round. The soils found here are very low in organic matter and highly saline, and available water is limited to a short period of time during the summer. Only a few species of higher soil fauna (including nematodes, rotifers and tardigrades) are capable of surviving these conditions. However, the simplicity of the communities and potential climate change impacts makes it a highly valuable system to research. Key areas of research include the study of the biogeography of soil fauna throughout the McMurdo Dry Valleys (i.e. why are the animals where they are) and how will the system might respond to climate changes (both gradual and extreme events).
Nielsen UN, (2019) 'Soil Fauna Assemblages. Global to Local Scales.' Cambridge University Press, https://www.cambridge.org/core/books/soil-fauna-assemblages/CB0D9389712AD92B02465A9799EB06EC (opens in a new window)
Hiltpold I, Johnson SN, Le Bayon R-C & Nielsen U (2017). Climate change in the underworld: impacts for soil-dwelling invertebrates. In Global Climate Change and Terrestrial Invertebrates (ed. by S.N. Johnson & T.H. Jones), pp. 201-228. Wiley-Blackwell, Chichester, UK.
Nielsen UN, Wall DH, (2010) 'Soil biodiversity in extreme soil environments', In: Jeffery, S. et al (Eds). European Atlas of Soil Biodiversity. European Commission, Publications Office of the European Union, Luxemburg. Chapter 3, section 7, pp 32-35
Wall DH, Nielsen UN, (2009) 'The Substrate of Life - Soils', In: The Wealth of Nature – Ecosystem Services, Biodiversity and Human Well-being. McNeely, JA. et al. (Eds). Conservation International. Washington, DC
Riis T, Brix H, Nielsen UN, (2008) 'Luronium natans in River Skjern, Denmark', In: Skjern å. Nielsen, I. et al. (Eds.) pp 185-200. In Danish.
Nielsen UN, (2005) 'Current distribution of Luronium natans in Denmark, URT (Danish botanical journal). In Danish.
Caruso T, Hogg ID, Nielsen UN, Bottos EM, Lee CK, Hopkins DW, Cary SC, Barrett JE, Allan Green TG, Storey BC, Wall DH, Adams BJ, (2019) 'Nematodes in a polar desert reveal the relative role of biotic interactions in the 1 coexistence of soil animals', Communications Biology, vol.2, Article no.63
Chieppa J, Nielsen UN, Tissue DT, Power SA, (2019) 'Drought and phosphorus affect productivity of a mesic grassland via shifts in root traits of dominant species', Plant and Soil, vol.444, no.s 1-2, pp 457-473
Lee CK, Laughlin DC, Bottos EM, Caruso T, Joy K, Barrett JE, Brabyn L, Nielsen UN, Adams BJ, Wall DH, Hopkins DW, Pointing SB, McDonald IR, Cowan DA, Banks JC, Stichbury GA, Jones I, Zawar-Reza P, Katurji M, Hogg ID, Sparrow AD, Storey BC, Allan Green TG, Cary SC, (2019) 'Biotic interactions are an unexpected yet critical control on the complexity of an abiotically driven polar ecosystem', Communications Biology, vol.2, Article no.62
van den Hoogen J, Geisen S, Routh D, Ferris H, Traunspurger W, Wardle DA, de Goede RGM, Adams BJ, Ahmad W, Andriuzzi WS, Bardgett RD, Bonkowski M, Campos-Herrera R, Cares JE, Caruso T, Caixeta LD, Chen XY, Costa SR, Creamer R, Castro JMD, Dam M, Djigal D, Escuer M, Griffiths BS, Gutierrez C, Hohberg K, Kalinkina D, Kardol P, Kergunteuil A, Korthals G, Krashevska V, Kudrin AA, Li, Q; Liang WJ, Magilton M, Marais M, Martin JAR, Matveeva E, Mayad E, Mulder C, Mullin P, Neilson R, Nguyen TAD, Nielsen UN, Okada H, Rius JEP, Pan K, Peneva V, Pellissier L, da Silva JCP, Pitteloud C, Powers TO, Powers K, Quist CW, Rasmann S, Moreno SS, Scheu S, Setala H, Sushchuk A, Tiunov AV, Trap J, van der Putten W, Vestergard M, Villenave C, Waeyenberge L, Wall DH, Wilschut R, Wright DG, Yang JI, Crowther TW, (20129) 'Soil nematode abundance and functional group composition at a global scale', Nature, vol.572, no.7768, pp 194-198
Wang X, Xiao S, Yang X, Liu Z, Zhou X, Du G, Zhang L, Guo A, Chen S, Nielsen UN, (2019) 'Dominant plant species influence nematode richness by moderating understory diversity and microbial assemblages', Soil Biology and Biochemistry, vol.137, Article no.107566
Gutt J, Isla E, Bertler AN, Bodeker GE, Bracegirdle TJ, Cavanagh RD, Comiso JC, Convey P, Cummings V, De Conto R, De Master D, di Prisco G, d'Ovidio F, Griffiths HJ, Khan AL, Lopez-Martinez J, Murray AE, Nielsen UN, Ott S, Post A, Ropert-Coudert Y, Saucede T, Scherer R, Schiaparelli S, Schloss IR, Smith CR, Stefels J, Stevens C, Strugnell JM, Trimborn S, Verde C, Verleyen E, Wall DH, Wilson NG, Xavier JC, (2018) 'Cross-disciplinarity in the advance of Antarctic ecosystem research', Marine Genomics, vol.37, pp 1-17
Jeffries TC, Rayu S, Nielsen UN, Lai KT, Ijaz A, Nazaries L, Singh BK, (2018) 'Metagenomic Functional Potential Predicts Degradation Rates of a Model Organophosphorus Xenobiotic in Pesticide Contaminated Soils', Frontiers in Microbiology, vol.9, Article no.147
Johnson SN, Lopaticki G, Aslam TJ, Barnett K, Frew A, Hartley SE, Hiltpold I, Nielsen UN, Ryalls JMW, (2018) 'Dryland management regimes alter forest habitats and understory arthropod communities', Annals of Applied Biology, vol.172, no.3, pp 282-294
Wang XT, Nielsen UN, Yang XL, Zhang LM, Zhou XH, Du GZ, Li GX, Chen SY, Xiao S, (2018) 'Grazing induces direct and indirect shrub effects on soil nematode communities', Soil Biology & Biochemistry, vol.121, pp 193-201
Drigo B, Nielsen UN, Jeffries TC, Curlevski NJA, Singh BK, Duursma RA, Anderson IC, (2017) 'Interactive effects of seasonal drought and elevated atmospheric carbon dioxide concentration on prokaryotic rhizosphere communities', Environmental Microbiology, vol.19, no.8, pp 3175-3185, Special Issue: SI
Jiang MK, Felzer BS, Nielsen UN, Medlyn BE, (2017) 'Biome-specific climatic space defined by temperature and precipitation predictability', Global Ecology and Biogeography', vol.26, no.11, pp 1270-1282
Rayu S, Nielsen UN, Nazaries L, Singh BK, (2017) 'Isolation and Molecular Characterization of Novel Chlorpyrifos and 3,5,6-trichloro-2-pyridinol-degrading Bacteria from Sugarcane Farm Soils', Frontiers in Microbiology, vol.8, Article no.518
Frew A, Barnett K, Riegler M, Nielsen UN, Johnson SN, (2016) 'Belowground ecology of scarabs feeding on grass roots: current knowledge and future directions for management in Australasia', Frontiers in Plant Science, vol.7, p 321
Lyons WB, Deuerling K, Welch KA, Welch SA, Michalski G, Walters WW, Nielsen U, Wall DH, Hogg I, Adams BJ, (2016) 'The Soil Geochemistry in the Beardmore Glacier Region, Antarctica: Implications for Terrestrial Ecosystem History', Scientific Reports, vol.6, Article no.26189
Power SA, Barnett KL, Ochoa-Hueso R, Facey SL, Gibson-Forty EVJ, Hartley SE, Nielsen UN, Tissue DT, Johnson SN, (2016) 'DRI-Grass: A new experimental platform for addressing grassland ecosystem responses to future precipitation scenarios in South-East Australia', Frontiers in Plant Science, vol.7, Article no.1373
Soong JL, Nielsen UN, (2016) 'The role of microarthropods in emerging models of soil organic matter', Soil Biology & Biochemistry, vol.102, pp 37-39, SI
Soong JL, Vandegehuchte ML, Horton AJ, Nielsen UN, Denef K, Shaw EA, de Tomasel CM, Parton W, Wall DH, Cotrufo MF, (2016) 'Soil microarthropods support ecosystem productivity and soil C accrual: Evidence from a litter decomposition study in the tallgrass prairie', Soil Biology and Biochemistry, vol.92, pp 230-238
Torode MD, Barnett KL, Facey SL, Nielsen UN, Power SA, Johnson SN, (2016) 'Altered precipitation impacts on above-and below-ground grassland invertebrates: Summer drought leads to outbreaks in spring', Frontiers in Plant Science, vol.7, Article no.1468
Aslam TJ, Benton TG, Nielsen UN, Johnson SN, (2015) 'Impacts of eucalypt plantation management on soil faunal communities and nutrient bioavailability: trading function for dependence?', Biology and Fertility of Soils, vol.51, no.5, pp 637-644
Bennett JR, Shaw JD, Terauds A, Smol JP, Aerts R, Bergstrom DM, Blais JM, Cheung WWL, Chown SL, Lea M-A, Nielsen UN, Pauly D, Reimer KJ, Riddle MJ, Snape I, Stark JS, Tulloch VJ, Possingham HP, (2015) 'Polar lessons learned: informing long-term management based on shared threats in Arctic and Antarctic environments', Frontiers in Ecology and the Environment, vol.13, pp 316-324
Hu J, Wu JH, Ma MJ, Nielsen UN, Wang J, Du GZ, (2015) 'Nematode communities response to long-term grazing disturbance on Tibetan plateau', European Journal of Soil Biology, vol.69, pp 24-32
Nielsen UN, (2015) 'Nematodes as indicators of ecosystem responses to altered precipitation regimes: Observed responses and future perspectives', Journal of Nematology, vol.47, no.3, pp 259-259
Nielsen UN, Ball BA, (2015) 'Impacts of altered precipitation regimes on soil communities and biogeochemistry in arid and semi-arid ecosystems', Global Change Biology, vol.21, pp 1407-1421
Nielsen UN, King CA, (2015) 'Abundance and diversity of soil invertebrates in the Windmill Islands region, East Antarctica', Polar Biology, vol.38, pp 1391-1400
Nielsen UN, Prior S, Delroy B, Walker JKM, Ellsworth DS, Powell JR, (2015) 'Response of belowground communities to short-term phosphorus addition in a phosphorus-limited woodland', Plant and Soil, vol.391, no.1-2, pp 321-331
Nielsen UN, Wall DH, Six J, (2015) 'Soil Biodiversity and the Environment', Annual Review of Environment and Resources, vol.40, pp 63-90
Vandegehuchte ML, Sylvain ZA, Reichmann LG, De Tomasel CM, Nielsen UN, Wall DH, Sala OE, (2015) 'Responses of a desert nematode community to changes in water availability', Ecosphere, vol.6, no.3, Article no.44
Wall DH, Nielsen UN, Six J, (2015) 'Soil biodiversity and human health', Nature, vol.528, pp.69-76
Cotrufo MF, Soong J, Vandegehuchte ML, Nguyen T, Denef K, Shaw A, Sylvain ZA, de Tomasel CM, Nielsen UN, Wall DH, (2014) 'Naphthalene addition to soil surfaces: A feasible method to reduce soil micro-arthropods with negligible direct effects on soil C dynamics', Applied Soil Ecology, vol.74, pp 21-29
Langford EA, Nielsen UN, Johnson SN, Riegler M, (2014) 'Susceptibility of Queensland fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), to entomopathogenic nematodes', Biological Control, vol.69, pp 34-39
Levy JS, Fountain AG, Gooseff MN, Barrett JE, Vantreese R, Welch KA, Lyons WB, Nielsen UN, Wall DH, (2014) 'Water track modification of soil ecosystems in the Lake Hoare basin, Taylor Valley, Antarctica', Antarctic Science, vol.26, pp 153-162
Nielsen UN, Ayres E, Wall DH, Li G, Bardgett RD, Wu T, Garey JR, (2014) 'Global-scale patterns of assemblage structure of soil nematodes in relation to climate and ecosystem properties', Global Ecology and Biogeography, vol.23, no.9, pp 968–978
Frew A, Nielsen UN, Riegler M, Johnson SN, (2013) 'Do eucalypt plantation management practices create understory reservoirs of scarab beetle pests in the soil?', Forest Ecology and Management, vol.306, pp 275-280
Nielsen UN, Wall DH, (2013) 'The future of soil invertebrate communities in polar regions: Different climate change responses in the Arctic and Antarctic?' Ecology Letters, vol.16, no.3, pp 409-419
Fierer N, Leff JW, Adams BJ, Nielsen UN, Bates ST, Lauber CL, Owens S, Gilbert JA, Wall DH, Caporaso JG, (2012) 'Cross-biome metagenomic analyses of soil microbial communities and their functional attributes', Proceedings of the National Academy of Sciences of the United States of America, vol.109, no.52, pp 21390-21395
Johnson SN, Nielsen UN, (2012) 'Foraging in the Dark - Chemically Mediated Host Plant Location by Belowground Insect Herbivores', Journal of Chemical Ecology, vol.38, no.6, pp 604-614
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
Nielsen UN, Wall DH, Adams BJ, Virginia RA, Ball BA, Gooseff MN, McKnight DM, (2012) 'The ecology of pulse events: insights from an extreme climatic event in a polar desert ecosystem', Ecosphere, vol.3, no.2, Article 17
Smith TE, Wall DH, Hogg ID, Adams BJ, Nielsen UN, Virginia RA, (2012) 'Thawing permafrost alters nematode populations and soil habitat characteristics in an Antarctic polar desert ecosystem', Pedobiologia, vol.55, no.2, pp 75-81
Stanish LF, Kohler TJ, Esposito RMM, Simmons BL, Nielsen UN, Wall DW, Nemergut DR, McKnight DM, (2012) 'Extreme streams: flow intermittency as a control on diatom communities in meltwater streams in the McMurdo Dry Valleys, Antarctica', Canadian Journal of Fisheries and Aquatic Sciences, vol.69, no.8, pp 1405-1419
Wall DH, Nielsen UN, (2012) 'Biodiversity and ecosystem services; is it the same belowground?', Nature Education Knowledge, vol.3, no.12, p 8
Nielsen UN, Ayres E, Wall DH, Bardgett RD, (2011) 'Soil biodiversity and carbon cycling: a synthesis of studies examining diversity-function relationships', European Journal of Soil Science, vol.62, no.1, pp 105-116
Nielsen UN, Wall DH, Adams BJ, Virginia RA, (2011) 'Antarctic nematode communities: observed and predicted responses to climate change', Polar Biology, vol.34, no.11, pp 1701-1711
Nielsen UN, Wall DH, Toro M, Adams BJ, Virginia RA, (2011) 'Nematode communities of Byers Peninsula, Livingston Island, maritime Antarctica', Antarctic Science, vol.23, no.4, pp 349-357, doi:10.1017/S0954102011000174
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 5(7): e11567. doi:10.1371/journal.pone.0011567
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, vol.37, no.7, pp 1317-1328
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 & Biochemistry, vol.40, no.6, pp 1538-1541
Nielsen UN, Riis T, Brix H, (2006) 'The effect of weed cutting on Luronium natans', Aquatic Conservation-Marine and Freshwater Ecosystems, vol.16, no.1, pp 409-417
Nielsen UN, Riis T, Brix H, (2006) 'The importance of vegetative and sexual dispersal of Luronium Natans', Aquatic Botany, vol.84, no.2, pp 165-170
Levy J, Fountain A, Gooseff MN, Barrett JE, Wall DN, Nielsen UN, Adams BJ, Lyons WB, (2012) 'Active Layer Processes in the McMurdo Dry Valleys, Antarctica: Decadal Trends and Experimental Responses to Changes in Soil Moisture' In: Hinkel, K.M. (ed.). Tenth International Conference on Permafrost. Vol. 1: International Contributions. The Northern Publisher, Salekhard, Russia, pages 221-226.