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Curriculum vitae

 



Ole Pedersen diving in Bali Ole Pedersen driving a boat in Greenland Ole Pedersen mounting a micro-respiration chamber Ole Pedersen mounting sulfide microelectrodes in Zostera marina


 

Name

Ole Pedersen

Born

March 28, 1963

Title

Associate Professor with M.Sc. in Acropetal Water Transport in Submerged Angiosperms (1991) and Ph.D. in Water and Gas Transport in Aquatic Plants (1995) both degrees from University of Copenhagen, Denmark.

Affiliation

The Freshwater Biological Laboratory, Biological Institute, University of Copenhagen Universitetsparken 4, 3rd floor, 2100 Copenhagen - E-mail OPedersen@bi.ku.dk

Research  Interests

  • Border disciplines of experimental eco-physiology and functional structure of higher aquatic plants
  • Environmental benefits and constrains at the land-water interface and implications for plant growth and re-colonization
  • Sustainable development and management of natural resources
  • Technology and instrumentation in biology - see Unisense A/S a Danish company specialised in microelectrodes and measuring systems

Employment

2006 to 2010: Adjunct Professor at Plant Biology, University of Western Australia

1999 to present: Associate Professor at the Freshwater Biological Laboratory, University of Copenhagen
2002 to 2004: Associate Professor at the Asian Institute of Technology
1996 to 1999: Assistant Professor at the Freshwater Biological Laboratory, University of Copenhagen

1995: Research position at The Ministry of Energetic and Environmental Affairs.

1995: Post Doctorate at The University of Århus. Experimental work with implications for gas and nutrient exchange when viscous diffusive boundary layers develop on surfaces of higher aquatic plants.

1993 to 1995: Ph.D. scholarship from the Carlsberg Foundation. Project title: Water and Gas Transport in Aquatic Plants.

1992: Research Associate with experimental field work on symbiotic organisms in freshwater financed by a research fellowship from the University of Copenhagen.

1991: Teaching Associate (Stream Ecology) at the University of Copenhagen.

1991: Research Associate (carbon kinetics and oxygen exchange to the sediment in Lobelia dortmanna) at the University of Copenhagen.

1991: Research Associate (carbon kinetics and oxygen exchange to the environment of the symbiotic ciliate Ophrydium versatile) at the University of Århus.

Research Experience

Plant-sediment interactions
I have my main research experience within the field of aquatic plant sediment interactions, i.e. how does the sediment affect the plants and vice versa? One of the more well described interactions is the release of oxygen form roots of aquatic plants to the surrounding rhizosphere. This release of oxygen to an otherwise anoxic environment has a tremendous impact on the microbial activities and the entire re mineralization of organic matter in aquatic sediments. I have addressed questions related to the root mediated release of oxygen to soils and sediments in a variety of plant communities ranging from crop plants (rice) over freshwater plant communities in oligotrophic lakes to seagrasses communities in temperate and tropical regions. Transport of gasses in aquatic plants is not only restricted to transport of oxygen from shoots to roots. Some aquatic plants are known to take up sediment-derived carbon dioxide with roots and the carbon dioxide diffuses to the shoot where it is fixed in the photosynthesis processes. In exchange, these plants are releasing the majority of oxygen produced in the photosynthesis to sediment. I have studied these plant communities applying microelectrodes in situ in order to elucidate effects of rising atmospheric carbon dioxide on submerged aquatic plant communities. Finally, I have recently demonstrated, also by means of microelectrodes, that under specific environmental conditions poisonous hydrogen sulfide enters roots and rhizomes of seagrasses and this may actually be the causal effect of worldwide die off events among seagrasses.

Water transport in submerged plants
In fully submerged aquatic plants, evapotranspiration cannot fuel a mass transport of water from roots to shoots. However, I have shown that submerged plants continue to transport water in the acropetal direction even in the absence of the transpiration stream. The water transport requires energy conversion in the roots and is probably driven by root pressure which also occurs in many terrestrial plants. I have developed new micro-techniques for studying submerged guttation in water plants and the results have shown that the water, carrying the inorganic nutrients and phytohormones produced in the roots, is directed to sites of active growth. In addition, my studies suggest that submerged plants have developed two important traits in the vascular tissue which are highly important in the absence of evapotranspiration; 1) truly submerged plants extend the Casparian band from the root to the stem and the petioles probably to avoid radial loss of nutrients before they reach the apical meristems and 2) huge xylem lacunae are formed to reduce flow resistance in the vascular system thereby saving energy spent on water transport purposes.

Micro and macro flow patterns around submerged plants
Together with a team of co-workers from the University of Aarhus I developed a flow micro-sensor. This flow sensor is capable of measuring flow velocities from 10 µm s-1 and up to 50 cm s-1. With this sensor I have studied flow patterns within the canopy of epiphytes on leaves of submerged plants. I have shown that different epiphyte canopy structure results in diverse flow patterns. Closely packed diatoms simply increase the diffusive boundary layer whereas the impact of loosely arranged canopy forming filamentous algae merely acts to increase turbulence over the leaf. In addition, I have used submerged macrophytes with different growth form to describe the macro flow patterns around macrophyte patches in streams. These studies have shown that the macrophyte canopy structure greatly influences the flow regime inside the patches. For instance, patches of Batrachium create a highly turbulent flow regime whereas patches of Sparganium impose little influence to overall stream flow.

Ecology of symbiotic freshwater ciliates
I have studied filtration rates and carbon and light kinetics of the colony forming symbiotic ciliate, Ophrydium versatile, and by means of oxygen microelectrodes I have described the oxygen dynamics of the spherical jelly in which Ophrydium is arranged. The diel oxygen budget closely resembles that of phytoplankton with a large positive oxygen surplus or put in another way, the animal behaves more like a plant in terms of overall oxygen metabolism. In addition, the light kinetics of Ophrydium also resembles that of phytoplankton because the ciliates are arranged in the periphery of the spherical jelly, which thereby generally reduces intra-colony resource competition such as self shading.

International Commissions Of Trust

Referee for:

  • Annales Botanici Fennici
  • Annals of Botany
  • Archiv für Hydrobiolgie
  • Aquatic Botany
  • Australian Journal of Plant Physiology
  • Canadian Journal of Fisheries and Aquatic Sciences
  • Global Change Biology
  • Hydrobiologia
  • New Phytologist
  • Journal of Ecology
  • Journal of Experimental Biology
  • Limnology and Oceanography
  • Marine Biology
  • Marine Ecology Progress Series
  • National Research Initiative Competitive Grants Program - Plant Responses to the Environment Program
  • New Phytologist
  • Ophelia
  • Plant and Soil (section editor)

Member of:

 

Guest Researcher

2010: 1 week at the University of Western Australia. Submergence tolerance of Melilotus siculus with Dr Teakle and Prof Colemer. Funded by A W Howard

2010: 1 week at the University of Sussex. In situ oxygen dynamics in Suaeda maritima with Prof Flowers. Funded by the EU COST action for halophytes

2010: 1 week at the University of Utrecht. Submergence tolerance of Arabidopsis and Rumex with Prof Voesenek. Funded by the Netherlands Organisation for Scientific Research (NWO)

2009: 6 months sabbatical at the University of Western Australia. Eco-physiology of aquatic plants from temporary wetlands with Dr Tim Colmer. Funded by the Danish National Science Council

2009: 1 week at the University of Utrecht. Submergence tolerance of Arabidopsis with Prof Voesenek. Funded by the Netherlands Organisation for Scientific Research (NWO)
2008: Distinguished visitor; 4 weeks at the University of Western Australia. Leaf gas films on Hordeum marinum with Dr. Tim Colmer. Funded by the School of Plant Biology, UWA

2007: Distinguished visitor; 4 weeks at the University of Western Australia. Leaf gas films on submerged rice with Dr. Tim Colmer. Funded by the School of Plant Biology, UWA

2006: 4 weeks at the University of Western Australia. Ecophysiology of the salt and flooding tolerant Halosarcia genus with Dr. Tim Colmer. Funded by the Carlsberg Foundation.
2005: 6 weeks at the University of Western Australia. Ecophysiology of the salt and flooding tolerant Halosarcia genus with Dr. Tim Colmer. Funded by the Danish Science Council.

2005: 3 weeks at the University of British Columbia. Respiration of non-biting midget larvae with Dr. Klaus Brodersen and Dr. Ian Walker. Funded by the Carlsberg Foundation

2005: 2 weeks at the University of Nijmegen with Dr. Liesje Mommer and Dr. Eric Visser. Flooding tolerance among terrestrial plants.

2004: 2 weeks at the University of Southern Denmark under the ASEM-DUO exchange program with M. Holmer and F.Ų. Andersen. Oxygen exchange with the environment in isoetids.

2002: 2 weeks at Confederació d'Associacions Empresarials de Balears (CAEB) in Mallorca. Oxygen dynamics in Mediterranean seagrasses with Prof Duarte funded by the EU
2000 & 2001: 2 weeks at the Virginia State University, USA with professor J. Zieman. Meristematic anoxia in Thalassia, Florida Bay. Funded by the Carlsberg Foundation

1998: 2 weeks at the Centre for Natural Resources and Environmental Studies, The Vietnam National University, Hanoi with professor Nguyen Hoang Tri. Prediction of the Resilience and Recovery of Disturbed Coastal Communities in the Tropics (SE Asia). EU funded.

1998: 3 weeks at the Institute of Tropical Biology, HCMC, Vietnam. Ecophysiology of tropical aquatic rosette plants. Funded by the WWF.

1997: 2 weeks at the International Rice Research Institute, Philippines. Oxygen and pH in the rhizosphere of rice. Funded by the Danish Science Council.

1997, 1999 & 2000: 2 weeks at the Marine Science Institute, Philippines. Oxygen in the rhizosphere of seagrasses. EU funded.

1995: 3 weeks at the Botanical Institute, University of Aarhus. Experimental work with pH polarization on leaves of aquatic plants and implications for inorganic carbon uptake.

1993: 1 week at the Lehrstuhle für Pflanzenphysiologie, Bayreuth Universität - Invited by Professor E. Steudle. Experimental work with the root pressure probe on Myriophyllum root systems.

1993: 1 week at the CEAB Laboratory in Blanes, Spain. Field work with Codium bursa, a marine macroalga of the Mediterranean.

1992: 2 weeks at The K.A. Timiriazev Plant Physiology Institute, The Academy of Sciences of Russia - Invited by Professor V.N. Zholkevich. Experimental work with plant water relations and mechanisms of root pressure.

Teaching

Since 1990, I have routinely taught university classes at the undergraduate and graduate levels. The courses include Lake Ecology, Stream Ecology, Aquatic Ecology, and Physiology and Ecology of Aquatic Plants. In addition, I have passed the pedagogical exam for associate professors offered by the Faculty of Sciences, University of Copenhagen.

In Asian Institute of Technology, I have been teaching Marine & Coastal Ecosystems, Coastal Biodiversity and Conservation, Wetland Ecosystem Management, and I have been supervising master and doctoral students from Thailand, Bangladesh, Cambodia, Vietnam, Indonesia and The Philippines.

Recreational

Advanced computer managing in Information Technology (IT) and INTERNET World Wide Web in science, SCUBA diving, natural history, and bicycle racing.

Publications

More than 100 published papers including journal papers, book chapters, reports, magazines, abstracts, internet articles et cetera