Doctor Kristine Crous

Kristine CrousDr Kristine Crous began research at the Hawkesbury Institute for the Environment as a postdoctoral research fellow in April 2012, coming to Western Sydney University from the Australian National University.

Her research has focussed on physiological mechanisms plants use to respond to global climate change factors, principally elevated CO2 and climate warming, but also the effect of nutrient availability (both nitrogen and phosphorus) on the CO2 response.

In her previous postdoc at WSU, she investigated how nutrient availability affects the responses of photosynthesis and leaf respiration to elevated CO2 at EucFACE. In a unique project linking phosphorus (P) limitations to photosynthesis and growth, she combined extensive field work at EucFACE measuring gas exchange with low O2, a technique often used in labs but rarely in the field. These measurements were combined with challenging labwork critical to elucidate the observed field mechanisms during which she extracted leaf P and other P-containing components from the leaf. This work resulted in new insights in the role of photorespiration, regarded as a wasteful process, in leaf P-recycling.

She also has been pursuing the temperature responses of photosynthesis and respiration on large trees at the Hawkesbury Forest Experiment. Because of unprecedented rates of warming expected in this century, she has investigated the capacity of Eucalyptus species to adjust to warmer conditions, mostly on large trees. She demonstrated that warming reduced leaf respiration at a given temperature in summer, with drought further exacerbating this reduction (Crous et al. 2011). In a warming study on Eucalyptus globulus (Crous et al. 2013) she reported a physiological temperature limit in summer because air temperatures far exceeded the temperature optimum of the species. Building on this work, she and her collaborators found less capacity to cope with warming within two widely-distributed Eucalyptus species ranging from tropical to temperate climates (Drake et al. 2015). Her data have been incorporated in several large-scale models to understand future ecosystem functioning.

Recently, she won a 2016 ARC Discovery Early Career Award (DECRA) to investigate how rainforest species will cope with climate warming. The response of rainforest species to climate warming is one of the largest uncertainties in the future terrestrial carbon cycle. This work aims to give us a predictive capacity for the temperature sensitivity of unique rainforest species. A narrow temperature optimum of photosynthesis is expected in rainforests as these species are thought to be more specialised due to a thermally stable environment. This may mean reduced rates with warming if they have limited capacity to adjust. The multi-faceted nature of her DECRA proposal, combining observational and experimental approaches, will maximise our understanding of how, and how much, rainforest tree species will adjust to warmer temperatures while also relating these responses to climate variability.

Areas of research

Leaf-level ecophysiology and biochemistry; photosynthesis and respiration; elevated CO2; ozone; nutrient cycling; climate change; sapflow
My research uses a combination of field work and controlled environment facilities in order to examine how plant metabolism responds to future climate change. I have a wide network of colleagues to collaborate with worldwide and from a range of disciplines including ecology, modelling and biochemistry.

Supervision Opportunities

As I am currently building my own labgroup and I am looking to talk to potential PhD students. If you are interested in working on climate change science or ecophysiology, or you have your own exciting ideas, then come and have a chat.

Teaching expertise

  • 2007 Field Laboratory Instructor at the Hawkesbury Forest Experiment
  • 2006 Undergraduate Student Instructor in Introductory Biology (BIO 162) leading discussion sessions and labs. University of Michigan, Ann Arbor, Michigan
  • 2003 – 2005 Mentoring and training of students in the Plant Physiology lab (basic skills such as sample preparation, organizing data and measuring with the Li-Cor 6400. University of Michigan, Ann Arbor, USA)
  • 2002 Graduate Student Instructor in Plant Physiological Ecology (ENVIRON 457). University of Michigan, Ann Arbor, Michigan
  • 2001 Certification and training for high school teaching in Biology and other sciences. University of Antwerp, Belgium

Awards and achievements

  • 2016 J G Russell Award from the Australian Academy of Science
  • 2010 Travel award from Australian National University: travel to Oxford NP symposium
  • 2008 Rackham Dissertation Award (University of Michigan): competitive funding to finish Ph.D dissertation
  • 2005 Samuel Graham Award for excellent scientific writing (University of Michigan)

Grants

  • 2016 – Australian Research Council Discovery Early Career Research Award (opens in a new window) – $379,500
  • 2002 – 2003 Philips Fellowship of the Belgian American Educational Foundation (BAEF), support for a full academic year including tuition and stipend – $ 50,000
  • 2001 – 2002 Wheeler Family Memorial Scholarship, SNRE (Recruitment fellowship) - $ 70,000

Selected publications

Ellsworth DS, Anderson IC, Crous KY, Cooke J, Drake JE, Gherlenda AN, Gimeno TE, Macdonald CA, Medlyn BE, Powell JR, Tjoelker MG, Reich PB, (2017) 'Elevated CO2 does not increase eucalypt forest productivity on a low-phosphorus soil', Nature Climate Change, vol.7, no.4, pp 279-282

Sharwood RE, Crous KY, Whitney SM, Ellsworth DS, Ghannoum O, (2017) 'Linking photosynthesis and leaf N allocation under future elevated CO2 and climate warming in Eucalyptus globulus', Journal of Experimental Botany, vol.68, no.5, pp 1157-1167

Tcherkez G, Gauthier P, Buckley TN, Busch FA, Barbour MM, Bruhn D, Heskel MA, Gong XY, Crous K, Griffin KL, Way DA, Turnbull MH, Adams MA, Atkin OK, Bender M, Farquhar GD, Cornic G, (2017) 'Tracking the origins of the Kok effect, 70 years after its discovery The 18 th New Phytologist Workshop 'The Kok effect: beyond the artefact, emerging leaf mechanisms ( KOALA)' Angers, France, July 2016', New Phytologist, vol.214, no.2, pp 506-510

De Kauwe MG, Lin YS, Wright IJ, Medlyn BE, Crous KY, Ellsworth DS, Maire V, Prentice IC, Atkin OK, Rogers A, Niinemets U, Serbin SP, Meir P, Uddling J, Togashi HF, Tarvainen L, Weerasinghe LK, Evans BJ, Ishida FY, Domingues TF, (2016) 'A test of the 'one-point method' for estimating maximum carboxylation capacity from field-measured, light-saturated photosynthesis', New Phytologist, vol.210, no.3, pp 1130-1144

Drake JE, Macdonald CA, Tjoelker MG, Crous KY, Gimeno TE, Singh BK, Reich PB, Anderson IC, Ellsworth DS, (2016) 'Short-term carbon cycling responses of a mature eucalypt woodland to gradual stepwise enrichment of atmospheric CO2 concentration', Global Change Biology, vol.22, no.1, pp 380-390

Duursma RA, Gimeno TE, Boer MM, Crous KY, Tjoelker MG, Ellsworth DS, (2016) 'Canopy leaf area of a mature evergreen Eucalyptus woodland does not respond to elevated atmospheric [CO2] but tracks water availability', Global Change Biology, vol.22, no.4, pp 1666-1676

Gherlenda AN, Crous KY, Moore BD, Haigh AM, Johnson SN, Riegler M, (2016) 'Precipitation, not CO2 enrichment, drives insect herbivore frass deposition and subsequent nutrient dynamics in a mature Eucalyptus woodland', Plant and Soil, vol.399, no.s 1-2, pp 29-39

Gimeno TE, Crous KY, Cooke J, O'Grady AP, Osvaldsson A, Medlyn BE, Ellsworth DS, (2016) 'Conserved stomatal behaviour under elevated CO2 and varying water availability in a mature woodland', Functional Ecology, vol.30, no.5, pp 700-709

Medlyn BE, De Kauwe MG, Zaehle S, Walker AP, Duursma RA, Luus K, Mishurov M, Pak B, Smith B, Wang Y-P, Yang X, Crous KY, Drake JE, Gimeno TE, Macdonald CA, Norby RJ, Power SA, Tjoelker MG, Ellsworth DS, (2016) 'Using models to guide field experiments: a priori predictions for the CO2 response of a nutrient- and water-limited native Eucalypt woodland', Global Change Biology, vol.22, no.8, pp 2834-2851

Ali AA, Medlyn BE, Aubier TG, Crous KY, Reich PB, (2015) 'Elevated carbon dioxide is predicted to promote coexistence among competing species in a trait-based model', Ecology and Evolution, vol.5, no.20, pp 4717-4733

Atkin OK, Bloomfield KJ, Reich PB, Tjoelker MG, Asner GP, Bonal D, Bönisch G, Bradford MG, Cernusak LA, Cosio EG, Creek D, Crous KY, Domingues TF, Dukes JS, Egerton JJG, Evans JR, Farquhar GD, Fyllas NM, Gauthier PPG, Gloor E, Gimeno TE, Griffin KL, Guerrieri R, Heskel MA, Huntingford C, Ishida FY, Kattge J, Lambers H, Liddell MJ, Lloyd J, Lusk CH, Martin RE, Maksimov AP, Maximov TC, Malhi Y, Medlyn BE, Meir P, Mercado LM, Mirotchnick N, Ng D, Niinemets U, O'Sullivan OS, Phillips OL, Poorter L, Poot P, Prentice IC, Salinas N, Rowland LM, Ryan MG, Sitch S, Slot M, Smith NG, Turnbull MH, Vanderwel MC, Valladares F, Veneklaas EJ, Weerasinghe LK, Wirth C, Wright IJ, Wythers KR, Xiang J, Xiang S, Zaragoza-Castells J, (2015) 'Global variability in leaf respiration in relation to climate, plant functional types and leaf traits', New Phytologist, vol.206, no.2, pp 614-636

Crous KY, Ósvaldsson A, Ellsworth DS, (2015) 'Is phosphorus limiting in a mature Eucalyptus woodland? Phosphorus fertilisation stimulates stem growth', Plant and Soil, vol.391, no.s 1-2, pp 293-305

Drake JE, Aspinwall MJ, Pfautsch S, Rymer PD, Reich PB, Smith RA, Crous KY, Tissue DT, Ghannoum O, Tjoelker MG, (2015) 'The capacity to cope with climate warming declines from temperate to tropical latitudes in two widely distributed Eucalyptus species', Global Change Biology, vol.21, no.1, pp 459-472

Ellsworth DS, Crous KY, Lambers H, Cooke J, (2015) 'Phosphorus recycling in photorespiration maintains high photosynthetic capacity in woody species', Plant, Cell and Environment, vol.38, no.6, pp 1142-1156

Quentin AG, Crous KY, Barton CVM, Ellsworth DS, (2015) 'Photosynthetic enhancement by elevated CO2 depends on seasonal temperatures for warmed and non-warmed Eucalyptus globulus trees', Tree Physiology, vol.35, no.11, pp 1249-1263

Gauthier PPG, Crous KY, Ayub G, Duan H, Weerasinghe LK, Ellsworth DS, Tjoelker MG, Evans JR, Tissue DT, Atkin OK, (2014) 'Drought increases heat tolerance of leaf respiration in Eucalyptus globulus saplings grown under both ambient and elevated atmospheric [CO2] and temperature', Journal of Experimental Botany, vol.65, no.22, pp 6471-6485

Weerasinghe LK, Creek D, Crous KY, Xiang S, Liddell MJ, Turnbull MH, Atkin OK, (2014) 'Canopy position affects the relationships between leaf respiration and associated traits in a tropical rainforest in Far North Queensland', Tree Physiology, vol.34, no.6, pp 564-584

Ali AA, Medlyn BE, Crous KY, Reich PB, (2013) 'A trait-based ecosystem model suggests that long-term responsiveness to rising atmospheric CO2 concentration is greater in slow-growing than fast-growing plants', Functional Ecology, vol.27, no.4, pp 1011-1022

Crous KY, Quentin AG, Lin Y-S, Medlyn BE, Williams DG, Barton CVM, Ellsworth DS, (2013) 'Photosynthesis of temperate Eucalyptus globulus trees outside their native range has limited adjustment to elevated CO2 and climate warming', Global Change Biology, vol.19, no.12, pp 3790-3807

De Kauwe MG, Medlyn BE, Zaehle S, Walker AP, Dietze MC, Hickler T, Jain AK, Luo Y, Parton WJ, Prentice IC, Smith B, Thornton PE, Wang S, Wang Y-P, Wårlind D, Weng E, Crous KY, Ellsworth DS, Hanson PJ, Seok Kim H, Warren JM, Oren R, Norby RJ, (2013) 'Forest water use and water use efficiency at elevated CO2: A model-data intercomparison at two contrasting temperate forest FACE sites', Global Change Biology, vol.19, no.6, pp 1759-1779

Barton CVM, Duursma RA, Medlyn BE, Ellsworth DS, Eamus D, Tissue DT, Adams M, Conroy JP, Crous KY, Liberloo M, Löw M, Linder S, McMurtrie R, (2012) 'Effects of elevated [CO2] on instantaneous transpiration efficiency at leaf and canopy scales in Eucalyptus saligna', Global Change Biology, vol.18, pp 585-595

Crous KY, Zaragoza-Castells J, Ellsworth DS, Duursma RA, Löw M, Tissue DT, Atkin OK, (2012) 'Light inhibition of leaf respiration in field-grown Eucalyptus saligna in whole-tree chambers under elevated atmospheric CO2 and summer drought', Plant, Cell and Environment, vol.35, pp 966-976

Ellsworth DS, Thomas R, Crous KY, Palmroth S, Ward E, Maier C, DeLucia EH, Oren R, (2012) 'Elevated CO2 affects photosynthetic responses in canopy pine and subcanopy deciduous trees over 10 years: a synthesis from Duke FACE', Global Change Biology, vol.18, pp 223-242

Medlyn BE, Duursma RA, Eamus D, Ellsworth DS, Colin Prentice I, Barton CVM, Crous KY, de Angelis P, Freeman M, Wingate L, (2012) 'Corrigendum: Reconciling the optimal and empirical approaches to modelling stomatal conductance', Global Change Biology, vol.18, no.11, p 3476

Crous KY, Zaragoza-Castells J, Löw M, Ellsworth DS, Tissue DT, Tjoelker MG, Barton CVM, Gimeno TE, Atkin OK, (2011) 'Drought accentuates acclimation of leaf respiration to summer heat: a comparison of Eucalyptus saligna trees growing under ambient and elevated atmospheric CO2', Global Change Biology, vol.17, pp 1560-1576

Medlyn BE, Duursma RA, Eamus D, Ellsworth DS, Barton CVM, Prentice C, Crous KY et al, (2011) 'Reconciling the optimal and empirical approaches to modelling stomatal conductance', Global Change Biology, vol.17, pp 2134-2144

Crous KY, Hunter MD, Reich PB, Ellsworth DS, (2010) 'Leaf N controls the photosynthetic CO2 response of grassland species exposed to nine years of free-air CO2 enrichment', Global Change Biology, vol.16, pp 2076-2088

Franklin O, McMurtrie RE, Iversen CM, Crous KY, Finzi A, et al, (2009) 'Forest fine-root production and nitrogen use under elevated CO2: Contrasting responses in evergreen and deciduous trees explained by a common principle', Global Change Biology, vol.15, pp 132-144

Crous KY, Walters MB, Ellsworth DS, (2008) 'Changes in leaf photosynthesis-N relationships over time in Pinus taeda exposed to long-term elevated CO2 and N fertilization in FACE', Tree Physiology, vol.28, pp 607-614

Crous KY, Vandermeiren K, Ceulemans R, (2006) 'Physiological responses to cumulative ozone uptake in two white clover (Trifolium repens L. cv. Regal) clones with different ozone sensitivity', Environmental and Experimental Botany, vol.58, pp 169-179

Crous KY, Ellsworth DS, (2004) 'Canopy position affects photosynthetic adjustments to long-term CO2 enrichment (FACE) in a mature Pinus taeda L. forest', Tree Physiology, vol.24, pp 961-970

Selected Conference Presentations

  • 2015 Crous KY. Turning up the heat: how do plants respond to climate warming? Invited presentation at the Birmingham Institute of Forest Research (BIFOR), University of Birmingham, 8 Sept.
  • 2014 Sharwood RE, Crous KY, Drake JE, Aspinwall MA, Whitney SM, Tjoelker MG and Ghannoum, O. Testing the limits of photosynthetic plasticity in Eucalyptus species from different biogeographical habitats. Combio, Canberra, 28 Sept – 2 Oct.
  • 2014 Crous KY, Ósvaldsson A and Ellsworth DS. Is phosphorus limiting in a mature Eucalyptus woodland? Phosphorus fertilisation stimulates stem growth. Combio, Canberra, 28 Sept – 2 Oct
  • 2013 Gimeno TE, Crous KY, Cooke J, O'Grady AP, Ellsworth DS. Elevated CO2 in an Australian woodland (EucFACE): impact of contrasting water availability on carbon uptake and water use in a nutrient-limited ecosystem - EcoTAS13 meeting in Auckland, New Zealand - 24 to 29 November
  • 2013 Crous KY, Osvaldsson A, Ellsworth D - Elevated CO2 in an Australian woodland (EucFACE): Are phosphorus limitations to trees "truth or myth"? - EcoTAS13 meeting in Auckland, New Zealand - 24 to 29 November
  • 2012 Ellsworth DS, Crous KY, Gimeno T, Ghannoum O, Boer M - Eucalyptus Free-air CO2 enrichment ('EucFACE') and how atmospheric CO2 may affect Cumberland Plain biodiversity - Presented at ESA Annual Conference, 3-7 December, Albert Park, Melbourne
  • 2009 Crous KY. Drought accentuates acclimation of leaf respiration to summer heat: a comparison of Eucalyptus saligna trees growing under ambient and elevated atmospheric CO2. COMBIO conference 2009, Christchurch, New Zealand, December 6-10th and at 24th New Phytologist Symposium, Oxford, UK in April 2010.
  • 2007 Crous KY, Walters MB, Ellsworth DS. Changes in leaf photosynthesis-N relationships over time in Pinus taeda exposed to long-term elevated CO2 and N fertilization in FACE. COMBIO conference 2007, 22-26 September and ECOFIZZ 2007 (27-28 September) in Sydney.
  • 2006 Crous KY. How is the relationship between photosynthesis and nitrogen affected by long-term elevated CO2? Invited presentation at the Modelling Workshop, Australia
  • 2006 Crous KY .Nitrogen addition affects the photosynthetic capacity of loblolly pine to elevated CO2 in FACE. IUFRO Canopy Processes Workshop: "Regional forest responses to environmental change", Boston, USA
  • 2003 Crous KY.Is forest tree functioning enhanced by elevated CO2? Invited presentation at the Terrestrial Ecosystems Forum, University of Michigan, Ann Arbor, USA