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Netherlands Institute of Ecology (NIOO-KNAW)

constantly mixed by burrowing animals. A totally different world.’ ‘The diversity of marine bacteria is enormous: one millilitre

of clear seawater can contain a million bacteria and 10 million viruses, even though the water is really clean.

Multiply that by the number of millilitres in the sea!’ ‘It will be a big step forward, if we can convince hydrologists and engineers that there’s something living in their sandpit.’‘We have three recommendations

for lake restoration: introduce zebra mussels, create islands to reduce the wind fetch and resuspension of the sediment, and create or allow greater water-level fluctuations.’ ‘Even if all the animals vanished from Earth, the processes would keep on going – though if the only agents left were micro-organisms, many would take far longer. Micro-organisms are the bottom line in maintaining the cycles.’‘Our

research yielded new insights into the evolution of warmblooded animals. They probably evolved as a by-product of herbivory, and therefore not primarily as fast-running predators.’

‘The songbird great tit (Parus major) can serve as a model species for humankind.We research personalities,their heritability, and the consequences in life. Furthermore, we look at parent–offspring relationships and when interests

are conflicting.’ ‘Everything we eat, drink, or wear is linked to the soil at one stage or another. Not only nutrient cycles, but also interactions and communication pass 2 through the soil.’‘We have found progress report

a combination of two bacteria that have no effect in isolation, but control a harmful fungus completely when they are applied together. Bingo!’ ‘First there was a

Then, after the Cambrian explosion and the burrowing revolution, the

sea floor covered in microbial mats.

sediment was constantly mixed by burrowing animals. A totally different world.’ ‘The diversity of marine bacteria is enormous: one millilitre of clear seawater can contain a million bacteria and 10 million viruses, even though the water is really clean. Multiply that by

the number of millilitres in the sea!’

‘It will be a big step forward, if we can convince hydrologists

and engineers that there’s something living in their sandpit.’‘We have three recommendations

for lake restoration: introduce zebra mussels, create islands to reduce the wind fetch and resuspension of the sediment, and create or allow greater water-level fluctuations.’ ‘Even if all the animals vanished from Earth, the processes would keep on going – though if the only agents left were micro-organisms, many would take far longer. Micro-organisms are the bottom line in maintaining the


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Netherlands Institute of Ecology (NIOO-KNAW) Editor: Froukje Rienks 2009

CREDITS Nieuwersluis, The Netherlands 2009

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ISBN: 978-90-74638-20-3 ISSN: 1380-1880 Text: Froukje Rienks Design: Monique Beijaert Data: Michel van Raaphorst, Aart van Oploo, Marianne van der Heijden, Machiel van der Grift Photographs: NIOO employees, Dreamstime (cover, p. 20, p. 31), Victor Eggenhuizen (p. 10), Claus en Kaan Architecten (p. 40, p. 41) Print: Badoux, Houten, The Netherlands. An FSC certified company, e.g. using plant-based inks and environmentally friendly detergents. Paper: Gmund FSC

The Netherlands Institute of Ecology is a research institute of the Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam.

CONTENTS The director’s vision NIOO and the world of ecology The NIOO t(h)ree The science of nature Centre for Estuarine and Marine Ecology Ecosystem Studies: ‘Bioturbation was Darwin’s last idea’ Marine Microbiology: ‘We’ve been waiting for this possibility to study interacting micro-organisms’ Spatial Ecology: ‘Pretty patterns can be highly relevant for survival and nature conservation’ Centre for Limnology Aquatic Food Webs: 'Unexpected relationships in food webs are the most interesting' Microbial Wetland Ecology: ‘Does microbial diversity matter? That’s the question’ Plant–Animal Interactions: ‘A swan need not be as picky as a cold-blooded lizard’

6 8 12 14

18 20 22

24 26 28

30 32 34

Business and finance Scientific publications Popularising science NIOO’s new sustainable building

36 38 39 40

Progress portal: Internet links




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5 Centre for Terrestrial Ecology Animal Population Biology: ‘Our data on the ecological effects of climate change is also important to politicians’ Multitrophic Interactions: ‘We have to abandon the concept that biodiversity benefits from stability’ Terrestrial Microbial Ecology: ‘Certain bacteria are very useful to have around’

The director’s vision

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or an ecologist there is never a dull moment at work! Ecology is the science of nature, and is curiosity-driven. After all, who doesn’t want to know how the biosphere functions, how life evolved to all its present beauty? Ecological science is one grand discovery tour into the hidden secrets of Mother Nature. In this report we would like to take you on that tour. However, ecology is also a science that needs to be applied. Our love for nature is not enough, on its own, to conserve it. Protection is desperately needed. In fact, the sad truth is that purely curiosity-driven ecological research on pristine ecosystems has come to an end. There are simply no ecosystems left that do not show the obtrusive influence of Homo sapiens. Present-day ecological research concentrates more

In this report you will find many examples of our societally driven studies, such as our work on climate change. What rise in temperature can ecosystems withstand? Can salt marshes help reduce the impact of tides when sea levels rise? Can we predict the effect of climate change on the timing of bird reproduction and the birds’ food sources? In addition, there are our studies on biological invasions, on toxic bacteria in our lakes, and on the bacterial community in the soil. Whether the research is driven by curiosity or by practical applications, the astounding complexity of nature remains our everyday business. We study life in its full breadth: from the genome of species to the community in interaction with its abiotic environment. Our interdisciplinary research tool box is as diverse as the systems we study, and we borrow the best tools and approaches from molecular biologists, chemists, physicists, mathematicians, and geologists to combine with our own. The Department of Ecosystem Studies works at the border of ecology and geochemistry. The Department of Spatial Ecology embraces physics, and our three microbial departments dig deeply into genomes. Our questions originate from nature. To answer them, we combine theoretical approaches with experiments in the field and in our high-tech laboratories. These questions deal with partnerships, sexual conflicts, and personalities in birds – yes, in birds too! They concern plant defence and the intriguing interactions between above- and belowground organisms, or on how organisms shape the landscape. Ecologists are masters of an integrative approach. More and more

often we learn that a larger, system-wide perspective is needed to understand the organisms and processes we study, and needed to understand nature. A genome has to be connected to the functioning of the individual in the complexity of its environment. Smallscale microbial processes add up to global nutrient cycles. Ecologists are just the right scientists to make these connections! We are struggling with increasing crises: financial, energy, and climate. There is a growing awareness that these crises are intrinsically linked. Society is sick of greedy bankers, air bubble economies, and fossil fuel addiction. Even, or rather especially, in times of economic malaise sustainability should remain high on the political and societal agenda – and on the economic agenda. That’s because there are also an infinite number of chances and challenges for the sustainable exploration of biodiversity. Think of new products and processes, new enzymes, new antibiotics, renewable energy, a bio-based economy, biological instead of chemical control of pests. There is a general feeling that the world should change. Ecologists can help. No more ivory towers: we have the obligation to communicate the results of our research to the general public, to policy makers and societal organisations, and we are happy to do so. To help build a new economy and a better society, one that respects our planet and all of its inhabitants. This three-year progress report conveys a selection of our competitive work in international science. I hope it will inspire you. Please let us know!

Prof. Dr. Louise E.M.Vet Director NIOO-KNAW

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and more on how various species cope with this (generally negative) human influence and what we can do to counteract or prevent it. To explore and understand biodiversity, and to preserve it – this is our general mission.

NIOO and the world of ecology The words ‘ecology’ and ‘ecological’ are used widely, from policy plans to ads. But what is the science of ecology, exactly? And what is NIOO’s role in the world of ecology? Ecology is a bustling, dynamic field of research with many cutting edges, at its interfaces with other sciences, and with society. Please read on… WHAT IS ECOLOGY? It is fascinating to study how nature works, and this is exactly what ecologists do. Their research aims to unravel the interactions between life and the environment. Ecology is all about interactions. How is it that a tiny insect can find the plant it feeds on, when it is kilometres

away? How can so many species coexist, even in the smallest drop of water? What causes a bird to adapt to a changing environment, or not? What wealth of microbial diversity lies hidden in the soil, and what are its functions? How can a small plant engineer an entire landscape? Ecologists search for


The Netherlands



WHAT IS NIOO? NIOO is short for the Netherlands Institute of Ecology (NIOO-KNAW). Three Dutch ecological research institutes, founded in the 1950’s, joined forces in 1992 to form NIOO. Working in all areas of ecology, NIOO now is the largest research institute of the Royal Netherlands Academy of Arts and Sciences (KNAW). With more than 225 people and a budget of about 16 million euros a year (read on in Business and finance), it also constitutes the largest and most diverse group of basic ecologists in the country.


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general patterns and rules within this wide range of interactions: that’s the essence of ecology.


NIOO’S HISTORY The Centre for Estuarine and Marine Ecology (CEME), originally founded as the Delta Institute for Hydrobiological Research to study ecological changes following the engineering works of the Delta Plan, is located in Yerseke on the banks of the Oosterschelde estuary. The Centre for Limnology (CL) lies on a 19th-century estate along the river Vecht in Nieuwersluis. CL was first called the Hydrobiological Institute. The Centre for Terrestrial Ecology (CTE) is situated in Heteren and was originally founded as the Institute for Ecological Research (IOO).

WHAT DO WE STUDY? Together, the three NIOO centres study animal, plant, and microbial ecology in terrestrial, freshwater, and marine environments. Estuaries and coastal waters worldwide, as well as the typically Dutch shallow inland waters and wetlands are studied to describe the functions of their ecosystems and the influence of human activity. How do organisms on land adapt to a changing world? Scientists share thoughts and theories across the classical and habitat divides,

HANDS-ON SCIENCE Open days always prove to be very enthusing for a wide audience. It is a successful example of the popularisation of science, where people can not only ask any question they like but also try some experiments themselves.

WHAT IS THE IMPORTANCE OF OUR WORK? NIOO performs basic and strategic ecological research. The research results help us, and many others, to understand the world around us, to fathom nature’s secrets and ingenious systems. But the basic knowledge acquired also supports nature conservation, nature and environmental policies, and plans for a sustainable society. It helps to predict and prevent the effects of climate change, biological invasions by exotic species, and land use

changes. NIOO has a research programme linked to the great environmental issues facing the world today. WHAT CHALLENGES DO WE FACE? Concern is growing about the availability of fresh water. Eutrophication is a worldwide

problem. Fisheries deplete the oceans while at the same time very little is known about how marine ecosystems function. How do we design sustainable production systems or effective nature reserves? And how do we manage large rivers, such as the Westerschelde? We have a downto-earth reason for supporting

R FOR ECOLOGISTS R is the hottest statistical programme of our decade. In the final months of 2008, NIOO scientists Karline Soetaert and Peter Herman published a book on the use of R for ecological modelling (A Practical Guide to Ecological Modelling: Using R as a Simulation Platform). This successful book covers the gamut of possibilities, including mechanisms, individual-based modelling, real-system down-to-earth engineering models, etc.

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merging micro- and macro-ecology on scales that range from genes to landscapes, and with combined results from the field, from models and from the lab. This multidisciplinary, collaborative approach has created unique opportunities to solve complex ecological problems.

TRAINING YOUNG SCIENTISTS NIOO engages in teaching and conducting research programmes with all Dutch universities that house an ecology department. An increasing number of NIOO scientists hold university chairs. To pass on expertise and knowledge, we train many young scientists at our institute. ecology’s aims: the need to prevent and stop deterioration, to combine conservation efforts and the sustainable exploitation of genetic, species, and ecosystem diversity. This is not only a labour of love – it is economically vital as well. Countless invaluable goods, compounds, and services come from the world’s ecosystems. Ecologists can provide essential basic scientific knowledge to society. Understanding the biosphere is crucial to our future.

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WHAT KIND OF COOPERATION IS NEEDED? To rise to the challenges mentioned, we must work in teams. NIOO scientists are part

A CENTURY OF BIRD RINGING Well, almost a century: NIOO accommodates the Dutch Centre for Avian Migration & Demography (Vogeltrekstation), which has maintained records on all birds ringed in the Netherlands since 1911. It relies on a small staff of professionals and numerous volunteers. Because of its long-range observation series, its database has become unique in the field.

of a worldwide network, actively collaborating with partners from 52 other countries (read on in Scientific publications). First of all, there are many links to other ecologists, and research locations can be found not only in the Netherlands but from the tropics to the poles. Another crucial type of interaction entails teaming ecologists with other scientists, including chemists, geologists, physicists, mathematicians, and molecular biologists. In science, breakthroughs often occur at the ‘cutting edges’ of different disciplines. Important developments in ecology lie at these crossroads: climate research, genomics, spatial ecology, biodiversity (in relation

to global change), the interaction between biological, geochemical and physical processes in water and the soil. Our close contact with more strategic and applied research partners facilitates the transfer from basic ecological knowledge to practical application. And one of the core tasks any good research institute must fulfil is outreach to end users, stakeholders, and society at large (read on in Popularising science). WHAT FACILITIES ARE NEEDED? From molecular laboratories to research vessels, from flow cytometers and isotope ratio mass spectrometers to aviaries: NIOO has access to an extensive range of facilities and equipment. All three centres feature mesocosms and climate rooms, where conditions can range from Antarctic to simulated global warming. Our flume tank was specially designed for biological hydrodynamic research. In the 1000-litre ‘limnotrons’ simple freshwater

MONITORING THE COAST NIOO’s Monitoring Taskforce gains insight into the natural development of coastal areas and estuaries, and the impact of human activity on them. The macrobenthic communities (i.e. the larger animals and algae living in or on the sea floor) of the Dutch Delta and the North Sea constitute the mainstay, with links to fish and birds. Long-term environmental monitoring is required to detect significant changes in an ecosystem’s status. The Taskforce manages a database of over 14 million validated entries on about 180 species, spanning 50 years. It has been the basis of many scientific studies and is used extensively to advise government authorities on policies and management. Since December 2006 the Monitor Taskforce has been KIWA-certified according to the ISO and NEN 9001-2000 standard for quality management. and remote sensing. The institute has compiled several long-term databases (e.g. boxes Monitoring the coast and A century of bird ringing) that make it possible to track ecological changes over decades.


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ecosystems can be studied. Our scientists use several greenhouses and an extensive experimental garden for plant, soil, and multitrophic research, and a total of 36 experimental ponds for aquatic biodiversity research. NIOO is also equipped for computer-based studies, like dynamic modelling


ISME OFFICE The office of ISME, the International Society for Microbial Ecology, has been based at NIOO since 2007. It has strong ties with the Department of Terrestrial Microbial Ecology.

GRANTS Scientists from four of the nine departments portrayed in this report have received a VICI (or its predecessor, the PIONIER) grant from the Netherlands Organization for Scientific Research (NWO), a prestigious national grant for excellence in science. NIOO participates in an impressive number of research programmes, including those funded by NWO and the European Union / ESF. For instance, NIOO scientists coordinated the European Network of Excellence for Marine Biodiversity and Ecosystem Functioning with 56 partners. The institute also plays an active role in organising meetings and developing new EU research programmes and networks.

The NIOO t(h)ree


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IOO’s structure over the period 2006-2008 can bbe best described as a tree. The NIOO tree has three T major branches, each of which m iis a research centre with its own habitat focus: sea and o coast, freshwater, and land. The organisation’s historical context, that of three separate institutes which merged in 1992 to form NIOO, can still be detected in these research centres. But the trunk of the tree is the ecological views and basic theories shared by all three. For instance, every research station has a department of microbial ecology – as microorganisms represent probably the greatest biodiversity in nature, and probably less than 5% of all microbial species have been identified. From each major branch sprout three lateral branches, which are the research departments presented here. Please sample these previews of our challenging work, and leaf through this Progress Report for more detailed information. X

The Centre for Estuarin The Centre for Limnolo The Centre for Terrestr

YERSEKE – THE CENTRE FOR ESTUARINE AND MARINE ECOLOGY Department of Ecosystem Studies ‘First there was a sea floor covered in microbial mats. Then, after the Cambrian explosion and the burrowing revolution, the sediment was constantly mixed by burrowing animals. A totally different world.’ p 18

Department of Marine Microbiology ‘The diversity of marine bacteria is enormous: one millilitre of clear seawater can contain a million bacteria and 10 million viruses, even though the water is really clean. Multiply that by the number of millilitres in the sea!’ p 20

Department of Spatial Ecology ‘It’s a big step forward to convince hydrologists and engineers that there’s something living in their sandpit.’ p 22


Depart Department rtm me of Animal Population Biology Popul ‘The songbird great tit (Parus major) can ‘Th serve as a model species for humankind. We study bird personality, its heritability, and its effect on fitness. Furthermore, we look at parent–offspring relationships where interests are often conflicting.’ p 30 Department of Multitrophic Interactions ‘Everything we eat, drink, or wear passes through the soil regularly. Soil organisms influence the species we see aboveground not only via nutrient cycles, but also by changing their communication signals.’ p 32 Department of Terrestrial Microbial Ecology ‘We have found a combination of two bacteria that have no effect in isolation, but control a harmful fungus completely when they are applied together. Bingo!’ p 34

ne and Marine Ecology / Yerseke

ogy / Nieuwersluis

rial Ecology / Heteren

A LIVING ORGANISM The NIOO tree is alive and budding. Twigs and branches grow. Temporary shunts or ‘anastomoses’ between departments are formed, for example to focus on topical issues. But twigs and branches may also go, and this reflects the dynamic structure of an internationally oriented, flexible, and high-quality research institute. Furthermore, NIOO is currently constructing a new, super-sustainable building which will house the two research centres now located in Heteren and Nieuwersluis under one roof (see NIOO’s new sustainable building).

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Updates: NIEUWERSLUIS – THE CENTRE FOR LIMNOLOGY Department of Aquatic Food Webs ‘We have three recommendations for lake restoration: use biomanipulation, create islands to reduce the wind fetch and resuspension of the sediment, and create or allow greater water-level fluctuations.’ p 24

Department of Microbial Wetland Ecology ‘Even if all the animals vanished from Earth, the processes would keep on going – though if the only agents left were micro-organisms, many would take far longer. Micro-organisms are the bottom line in maintaining the cycles.’ p 26

Department of Plant–Animal Interactions ‘Our research yielded new insights into the evolution of warm-blooded animals. They possibly evolved as a by-product of herbivory, and therefore not primarily as fast-running predators.’ p 28

The science of nature Below you’ll find some of our highest-ranking publications of the last three years. Though this is just a selection of the publications we are proud of, we hope you’ll find it inspiring.

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THE OCEAN’S NITROGEN FEED Increasing amounts of anthropogenic fixed nitrogen are entering the open ocean from the atmosphere, possibly accounting for up to a third of the ocean’s external nitrogen ‘feed’. This is stimulating the marine organisms’ production. Yet although 10% of the ocean’s drawdown of atmospheric anthropogenic carbon dioxide may result from this atmospheric nitrogen fertilisation, as much as two-thirds of this attenuation of radiative forcing may be offset by an increase in N2O emissions. The effects of increasing atmospheric nitrogen deposition are expected to continue to grow. R.A. Duce, J. LaRoche, K. Altieri, K.R. Arrigo, A.R. Baker, D.G. Capone, S. Cornell, F. Dentener, J. Galloway, R.S. Ganeshram, R.J. Geider, T. Jickells, M.M. Kuypers, R. Langlois, P.S. Liss, S.M. Liu, J.J. Middelburg, C.M. Moore, S. Nickovic, A. Oschlies, T. Pedersen, J. Prospero, R. Schlitzer, S. Seitzinger, L.L. Sorensen, M. Uematsu, O. Ulloa, M. Voss, B. Ward & L. Zamora, 2008. Impacts of atmospheric anthropogenic nitrogen on the open ocean, Science 320:893-897

INVADERS FROM THE SOUTH Many species are currently moving to higher latitudes and altitudes. Six of such range-expanding plant

species from a Dutch riverine area plus several related native species were put to the test of shoot and root enemy attack. The rangeexpanding species proved to be better defended and therefore experienced less control by aboveor belowground herbivores and pathogens. The results strongly suggest that plants that successfully extend their range have the potential to develop into invaders. T. Engelkes, E. Morriën, K.J.F.Verhoeven, T.M. Bezemer, A. Biere, J.A. Harvey, L.M. McIntyre, W.L.M. Tamis & W.H. van der Putten, 2008. Successful range-expanding plants experience less above-ground and below-ground enemy impact, Nature 456:946-948

WHAT USE ARE PATTERNS? Many ecosystems around the world exhibit striking spatial patterns which could partly be generated by processes within the ecosystem. An international research team headed by the NIOO has demonstrated that mussel beds create their own regular, spatial pattern in a process called spatial self-organisation. They used lab experiments, field experiments, and an individualbased computer model to show that interaction between individual mussels caused the observed patterns. This pattern, in turn, improved the mussels’ growth

and resistance to wave action. The results showed that spatial selforganisation needs to be considered in ecosystem conservation. J.Van de Koppel, J.C. Gascoigne, G. Theraulaz, M. Rietkerk, W.M. Mooij & P.M.J. Herman, 2008. Experimental evidence for spatial selforganization and its emergent effects in mussel beds ecosystems, Science 322:739-742

STABLE OR UNSTABLE DIVERSITY There is much debate about the link between species diversity and ecosystem stability. The traditional grassland biodiversity experiments involved hand-weeded artificial plant communities, but NIOO’s alternative experimental setup has challenged this approach. It turns out that the strictly positive relationship between the number of plant species and ecosystem stability found in sown and weeded communities is much more dynamic under more realistic conditions in naturally established plant communities. Highly diverse ecosystems can be both stable and unstable. T.M. Bezemer & W.H. van der Putten, 2007. Ecology: Diversity and stability in plant communities, Nature 446:E6-E7

P.F. Dunfield, A.Q. Yurgey, P. Senin, A.V. Smirnova, M.B. Stott, S. Hou, B. Ly, J.H. Saw, Z. Zhou, Y. Ren, J. Wang, B.W. Mountain, M.A. Crowe, T.M. Weatherby, P.L.E. Bodelier, W. Liesack, L. Feng, L. Wang & M. Alam, 2007. Methane oxidation by an extremely acidophilic bacterium of the phylum Verrucomicrobia, Nature 450:879-882

OCEAN-FLOOR CARBON BURIAL Less than 1 % of the carbon fixed by phytoplankton at the ocean surface is buried in oceanic sediments, but it still has major consequences for

J.J. Middelburg & F.J.R. Meysman, 2007. Burial at sea, Science 316:1294-1295

COMPLEX BUT STABLE Simple mathematical models predict that food webs become less stable as they become more complex, which is the opposite to what is observed in real ecosystems. A longterm study of dune soil ecosystems shows nature’s solution to this paradox. If a considerable part of the biomass involved stays at the base of food chains, with far more prey than predator, the resulting ‘pyramidal’ ecosystem can grow in productivity and complexity without losing its stability. Understanding how complex

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NEW METHANE GUZZLER Much of the greenhouse gas methane is produced in soil and sediment. Aerobic methaneconsuming bacteria can filter it out before it is emitted to the atmosphere – a very valuable ecosystem service, in the light of combating global climate change. Until recently, no methane eaters were known to thrive in extreme acidic environments, some of which produce methane. But now one has been discovered: a methanotroph that grows optimally at pH 2.0–2.5. Belonging to the Verrucomicrobia instead of the expected Proteobacteria, it appears to use a novel pathway to consume methane. This shows there is more diversity in bacterial methane eaters than we thought.

the global carbon cycle and oxygen accumulation in the atmosphere, and supports about 30 % of the total living biomass on Earth living in the depths of the ocean. During its journey to and into the ocean floor, the carbon degrades: rapidly at first, but then more slowly. In a commentary, NIOO biogeochemists stress the importance of a study by Rothman and Forney that explains the power-law carbon degradation. Limitation of the enzyme supply to reactive organic matter is what eventually leads to the inverse reactivity distribution that explains the power law. Insights into this mechanism that protects organic matter from degradation will help scientists evaluate the Earth’s carbon cycle.

The science of nature (continued)

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food webs assemble through time is fundamental both for ecological theory and for the development of sustainable strategies of ecosystem conservation and restoration.

Sex chromosome-linked species recognition and evolution of reproductive isolation in flycatchers, Science 318:95-97

A.-M. Neutel, J.A.P. Heesterbeek, J. van de Koppel, G. Hoenderboom, A. Vos, C. Kaldeway, F. Berendse & P.C. de Ruiter, 2007. Reconciling complexity with stability in naturally assembling food webs, Nature 449:599-602

NEED FOR MARINE BIODIVERSITY KNOWLEDGE Three marine biologists used their gguest editorial in Science to argue ffor better marine conservation aand more marine biodiversity kknowledge. Marine diversity is much more extensive, particularly m iin remote habitats such as the deep ocean, and vulnerable than d previously thought. Despite an p iincrease in research on biodiversity, only 10 % of the published research o deals with marine biodiversity. This disproportionally small research effort is in sharp contrast to the large genomic diversity in the oceans as compared to that on land. International cooperative efforts and networking should be increased, if we are to avoid being faced with a future of depleted marine resources.

ANTI-HYBRID PARTNER CHOICE Hybridisation of two species usually produces unfit offspring. How can this interbreeding be averted? In two hybridising flycatcher species, researchers from five countries demonstrated that species recognition is inherited on the Z chromosome. The same chromosome is also the known location of species-specific male plumage traits and genes causing low hybrid fitness, and limited recombination maintains these associations. So a female flycatcher will choose a mate who looks like her biological father, and will not fancy another species. S.A. Sæther, G.-P. Sætre, T. Borge, C. Wiley, N. Svedin, G. Andersson, T. Veen, J. Haavie, M.R. Servedio, S. Bureš, M. Král, M.B. Hjernquist, L. Gustafsson, J. Träff & A. Qvarnström, 2007.

I.E. Hendriks, C.M. Duarte & C.H.R. Heip, 2006. Biodiversity research still grounded, Science 312:1715

SEXUAL SELECTION HERE TO STAY Partner choice and competition for the best mate are important parts of evolutionary theory and are therefore closely studied by

C.M. Lessells, A.T.D. Bennett, T.R. Birkhead, N. Colegrave, S.R.X. Dall, P.H. Harvey, B. Hatchwell, D.J. Hosken, H.J., A.J. Moore, G.A. Parker, S. Pitnick, T. Pizzari, J. Radwan, M. Ritchie, B.C. Sheldon, D.M. Shuker, L.W. Simmons, P. Stockley, T. Tregenza & M. Zuk, 2006. Debating sexual selection and mating strategies, Science 312:689-690 And: T. Pizzari, T.R. Birkhead, M.W. Blows, R. Brooks, K.L. Buchanan, T.H. Clutton-Brock, P.H. Harvey, D.J. Hosken, M.D. Jennions, H. Kokko, J.S. Kotiaho, C.M. Lessells, C. Macias-Garcia, A.J. Moore, G.A. Parker, L. Partridge, S. Pitnick, J. Radwan, M. Ritchie, B.C. Sheldon, L.W. Simmons, R.R. Snook, P. Stockley & M. Zuk, 2006. Debating sexual selection and mating strategies. Science: 312:690

EXPERT PANEL NEEDED Arguing that biodiversity poses an even greater challenge to policymakers than climate change, in a commentary in Nature, an international group of researchers proposes an international panel of experts on biodiversity similar to the IPCC. The 1992 United Nations Earth Summit conference in Rio de Janeiro, Brazil, attracted much welldeserved attention to biodiversity. Even though life’s diversity is probably crucial to human well-being and sustainable development, we still lack proper representation on the world stage. M. Loreau, A. Oteng-Yeboah, M.T.K. Arroyo, D. Babin, R. Barbault, M. Donoghue, M. Gadgil, C. Häuser, C. Heip, A. Larigauderie, K. Ma, G. Mace, H.A. Mooney, C. Perrings, P. Raven, J. Sarukhan, P. Schei, R.J. Scholes and R.T. Watson, 2006. Diversity without representation, Nature 442:245-246

MISTIMING CAUSES POPULATION DECLINE The migratory pied flycatcher suffers from a probably widespread phenomenon: mistiming due to climate change. The birds fail to breed at the time the most food is available. In the last 20 years this has caused a decline of about 90 % in Dutch populations in areas where the nestling food peaks early in the

season. In areas with a relatively late food peak (other woodland types), early-breeding birds are still synchronous with their food supply and only a weak population decline is visible. However, these populations are also expected to dwindle if the climate-driven changes to the peak availability of their food – caterpillars – continue. C. Both, S. Bouwhuis, C. M. Lessells and M. E.Visser, 2006. Climate change and population declines in a long-distance migratory bird, Nature 441:81-83

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biologists. Darwin’s ideas about ‘sexual selection’ still provide the basic understanding of these behaviours, so when Roughgarden et al. claimed that sexual selection ‘is always mistaken’ and ‘needs to be replaced’ a group of top international researchers in this area responded strongly. They argued that Roughgarden had misrepresented the evidence and that her proposed alternative theory is not novel. They contend that sexual selection is still the best functional explanation for the evolution of the sex differences that initially puzzled Darwin, and for the variation between different kinds of plants and animals in mating and reproductive patterns.

‘Bioturbation was Darwin’s last idea’ The hallmarks of the Department of Ecosystem Studies are ecological modelling and the labelling of important elements, such as carbon, to follow their fate throughout an entire natural ecosystem. ‘Our department is positioned on the very border of ecology and biogeochemistry and combines the best concepts from both worlds.’ This work means that urgent questions on marine biodiversity and ecosystem functioning in a changing world can finally be answered.


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he department’s research deals with the diversity and functioning of marine and coastal animals and their influence on the ecosystem. The scientists use high-tech tools to integrate different scales in time and space, in order to unravel food webs – from molecules to predators, from a square metre to an entire estuary. ‘The really innovative work we do concerns our in-situ labelling studies where we label an important element, like carbon (C) or nitrogen (N), and follow its fate in a real ecosystem,’ says Jack Middelburg, head of the department. In addition to the classic 14C isotope, used for the dating of materials, carbon also has a natural 13C isotope. ‘This one tells ecologists what you are eating, where your energy comes from.’ BIG WORMS Three sources of food are available at tidal flats: dead organic matter, locally produced algae, and bacteria. The department studied the bacterial carbon with stable isotopes (2,3,4). The bacteria proved to be primarily a sink of organic carbon. ‘Nobody had looked at the bacteria in a food web in detail before. What’s their fate? How important are they to the ecosystem? To answer this you have to follow a whole ecosystem, not isolated species,’ explains Middelburg. ‘People always looked at either large worms and bivalves or bacteria – rarely did they examine them jointly. We are now merging those micro and macro visions. We have been the


In the sea floor, which covers about 70% of the Earth’s surface, a crucial role is reserved for the animals living there. What’s the impact of the moving, eating, burrowing macrofauna, sized one-cm and up? ‘Processes are driven by bacteria, and transport is driven by macrofauna,’ posits Middelburg. Bioturbation is the fancy name

Publication highlights 1. Meysman, Middelburg & Heip 2006 Bioturbation: a fresh look at Darwin’s last idea. TREE 21:688-695 2. Van Oevelen, Middelburg, Soetaert & Moodley 2006 The fate of bacterial carbon in an intertidal sediment: Modeling an in situ isotope tracer experiment. Limnology & Oceanography 51:1302-1314 3. Van Oevelen, Moodley, Soetaert & Middelburg 2006 The trophic significance of bacterial carbon in a marine intertidal sediment: Results of an in situ stable isotope labeling study. Limnology & Oceanography 51:2349-2359 4. Veuger,Van Oevelen, Boschker & Middelburg 2006 Fate of peptidoglycan in an intertidal sediment: An in situ 13 C-labeling study. Limnology & Oceanography 51:1572-1580

for mixing the sediment. Darwin was the first to recognise its importance (1). ‘His last book was about bioturbation.’ According to Middelburg, ‘it’s the archetypal example of ecosystem engineering and it played a key role in the early evolution of animal life. The sea floor evolved from a layered, unmixed ecosystem into a heterogeneous one, which was decisive for the transition from Precambrian to Cambrian.’ By making tunnels, and ventilating them to breathe – called bioirrigation – these sea bottom-dwelling animals influence other organisms, sediment chemistry and the transport and fate of carbon, oxygen, nitrates, and also contaminants. That’s why it’s so important to study it. ‘We are developing better concepts for particle mixing.’ Bioturbation exhibits a strong link with biodiversity. The loss of organisms near the ocean floor, e.g. due to increasing coastal hypoxia, will have significant consequences. Still, the vast majority of marine biodiversity is unknown, unprotected and endangered. NIOO scientist Carlo Heip led the Marine Biodiversity and Ecosystem Functioning (MarBEF) Network of Excellence, which concluded in 2008 with the successful first World Conference on Marine Biodiversity. Nearly 600 scientists from 42 countries agreed to the Valencia Declaration for the protection of marine biodiversity. ‘In the coming years, the department will be busy investigating the consequences of biodiversity loss on ecosystem level. In addition to climate-linked ocean acidification, especially at the poles where it shows up first,’ predicts Middelburg, soon to be a full professor of geochemistry at Utrecht University. They will be using Bayesian statistics. ‘If you are satisfied with understanding only, classical statistics is fine. But we want to be able to forecast as well.’


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first to study these food webs end-to-end with stable isotopes and models, and our approach has been followed by many others.’ This research also implies an important message for policymakers. ‘End-to-end food web thinking is essential for them. In this way, policy decisions (on nutrient cycles) and results (counted as the number of birds or the like) will be linked! The whole food web is found in between.’

‘We’ve been waiting for this possibility to study interacting micro-organisms’ progress report


The focal points of the Department of Marine Microbiology are photosynthesis, nitrogen fixation and carbon conversions. These basic processes, studied in microalgae, cyanobacteria and other bacteria, are as essential for the ecosystems of sea and coast as they are on land. It is now possible to research them in greater detail than previously. ‘We’ve seen a sweeping technological revolution in our field of study.’


he department’s scope is broader than that of an average microbiology department: it ranges from ecological and evolutionary to molecular and biogeochemical approaches. Developments are happening in quick succession. ‘Our team has now added a completely new method to the carbon study toolbox,’ explains Lucas Stal, head of the department and since 2007 the first and only professor of marine microbiology in the Netherlands. By combining liquid chromatography and isotope ratio mass spectrometry of stable carbon isotopes, it is possible to zoom in on carbohydrates produced by phototrophic organisms and consumed by non-phototrophs (1).‘This is attracting a

lot of international attention, as if everyone has been waiting for this possibility to study interacting microorganisms. It will be an important tool for fathoming the ecology of phototrophic organisms.’ TINY BUT MANY

Molecular techniques are invaluable when studying the huge as yet invisible diversity of microbes. ‘In the last few years we’ve considerably expanded our expertise and facilities in molecular ecology,’ says Stal. ‘And the Gordon and Betty Moore Foundation funded the sequencing of a number of important cyanobacteria from our culture collection.’ In the International Census of Marine Microbes pro-

In estuaries, the gradient from fresh to salty water causes high mortality in algae and a complete change in species composition. Linking fluore-scence measurements to a microscope made it possible to analyse the photosynthesis efficiency not only of community samples but also of single cells (2). This photosynthesis efficiency proved to be a true distinguishing species characteristic. A European ‘ferry boxes’ project will start this year, in which devices attached to ferries will take photosynthesis measurements automatically. ‘This will tell us more about the population dynamics of

algae and the fluctuations in their most important and characteristic process.’ FIXED FUNCTION

The role played by the element nitrogen is also significant. Only a few species are able to fix nitrogen gas and pull it into the food chain. Using a recently devised technique based on the nitrogen-fixing enzyme, the team was able to measure the presence of nitrogen fixation along a north-south transect in the Atlantic Ocean (5). Nitrogen fixation occurred between 14º North and 13º South only. In this area, the concentration of the nutrient phosphate had fallen by 75 %, because the micro-organisms here take up much more phosphate as – thanks to the nitrogen fixed – they can achieve a bigger biomass. The same technique was applied to microbial mats for the first time, on the beach of the Dutch Wadden island of Schiermonnikoog (4). Stal expounds: ‘The greater goal behind our research was to unravel the diversity of nitrogen-fixing cyanobacteria in these mat communities, and its function. We were able to prove the often mentioned but rarely demonstrated function that diversity of the actors leads to optimisation of the process.’ In this Greenbeach project, Stal’s team is also hoping to find out whether a microbial mat actually functions like one big organism – with different species performing different parts of processes, but at synchronised moments during the day.

Publication highlights 1. Boschker, Moerdijk-Poortvliet, Van Breugel, Houtekamer & Middelburg 2008 A versatile method for stable carbon-isotope analysis of carbohydrates by highperformance liquid chromatography - isotope ratio mass-spectrometry. Rapid Com. Mass Spectrometry 22:3902-3908 2. Dijkman & Kromkamp 2006 Photosynthetic characteristics of the phytoplankton in the Scheldt estuary: community and single-cell fluorescence mea surements. European Journal of Phycology 41:425-434 3. Haverkamp, Acinas, Doeleman, Stomp, Huisman & Stal 2008 Diversity and phylogeny of Baltic Sea picocyanobacteria inferred from their ITS and phycobiliprotein operons. Environmental Microbiology 10:174-188 4. Severin & Stal 2008 Light dependency of nitrogen fixation in a coastal cyanobacterial mat ISMEJ 2:1077-1088 5. Staal,Te Lintel Hekkert, Brummer,Veldhuis, Sikkens, Persijn & Stal 2007 Nitrogen fixation along a north-south transect in the eastern Atlantic Ocean. Limnology and Oceanography 52:1305-1316

Contact: +31-113-577 497 / 300

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ject they are studying the distribution and biodiversity of marine microbes. ‘We’re hoping to understand this biodiversity by looking at the underlying ecological and evolutionary processes,’ says Stal. The department’s scientists have also studied the diversity within picocyanobacteria of the Baltic Sea (3). These tiny cyanobacteria, less than a micrometre in diameter, can make up 80 to 90 per cent of the phytoplankton biomass. The coexistence of red and green strains proved to be widespread. How did this phenomenon evolve? ‘The presence of the red pigment gene within DNA almost identical to green pico’s points to only one explanation: horizontal gene transfer from another species to the red strain. We found three different evolutionary lineages based on this pigmentation, corresponding to different ecological niches underwater.’

‘Pretty patterns can be highly relevant for survival and nature conservation’ How does a landscape evolve? That’s the key question being addressed by the Department of Spatial Ecology. Organisms can shape the landscape as ecosystem engineers, but processes like water flow are equally important. ‘We like to stress the importance of the spatial interactions between those organisms and their environment.’ Basically this is ecology, but with a clear link to physics.


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ur study into the spatial self-organisation of mussels on the sea floor(4) showed the ecological relevance of intricate patterns. All we used was a basic set of behavioural rules,’ says head of department Peter Herman. If there are only a few mussels, they cluster together for safety. If there are many, they keep their distance, to safeguard their food supply. The result is a stripy pattern in the sea. Understanding the patterns and the underlying needs of organisms in order to survive can help conservation efforts. ‘This project really involved all steps of our research. We describe the situation in the field (1,6), look at the processes in the lab(2,6), model them (3,4), and then validate this in the field again(4,5) to see if we were right.’ Field checks also reveal what the scientists still can’t explain. According to Herman, the key to successful collaboration within a department is a shared point of view. He smiles. ‘Yes, you could call this self-organisation too, within the framework of a research institute.’ ANIMATING MODELS

An interesting discovery was the 5–10 cm high ‘plateaus’ in the Westerscheldt intertidal area that only occurred in animal-free experimental plots(1). ‘These silt-rich structures were caused by sediment-fixing diatom algae that were left ungrazed,’ elucidates Herman. ‘And they fitted earlier model predictions

perfectly.’ There are many things still to do at the interface between biology and hydrodynamics. For instance, not only removing small sea bottomdwelling organisms from real ecosystems, but also putting them into models that previously didn’t consider living organisms. A methodological breakthrough is the incorporation of realistic biological processes into a basic hydrological–morphodynamic model(3). As Herman puts it: ‘Usually, to simulate the occurrence of a saltmarsh plant, modellers slightly modified the bottom roughness. That way, you totally ignore the feedback of plant characteristics on water flow and erosion of the sediment(2).’ These abstract, theoretical models will eventually be merged with the detailed, process-based models. ‘The results of this study are already being applied.’ UPSCALING ‘We actually have a double message. Within ecology we like to stress the importance of spatial interactions – both biotic and abiotic – and the spatial organisation of the landscape. Secondly, we urge physicists and engineers to always take the effects of organisms into account in their models and systems.’ The Dutch project Building with Nature works this way. In 2008, a group of dredgers and engineers, tired of being confronted with adverse effects on nature after they had made their plans, started to try to incorporate social factors from the outset of

1. Montserrat,Van Colen, Degraer,Ysebaert & Herman 2008 Benthic community-mediated sediment dynamics. Mar Ecol Prog Ser 372:43-59 2. Peralta,Van Duren, Morris & Bouma 2008 Consequences of shoot density and stiffness for ecosystem engineering by benthic macrophytes in flow dominated areas: a hydrodynamic flume study. Mar Ecol Prog Ser 368:103-115 3. Temmerman, Bouma,Van de Koppel,Van der Wal, De Vries & Herman 2007 Vegetation causes channel erosion in a tidal landscape. Geology 35:631-634 4. Van de Koppel, Gascoigne,Theraulaz, Rietkerk, Mooij & Herman 2008 Experimental Evidence for Spatial Self-Organization and Its Emergent Effects in Mussel Bed Ecosystems. Science 322:739-742 5. Van der Wal, Herman, Forster,Ysebaert, Rossi, Knaeps, Plancke & Ides 2008 Distribution and dynamics of intertidal macrobenthos predicted from remote sensing: response to microphytobenthos and environment. Mar Ecol Prog Ser 367:57-72 6. Van Wesenbeeck,Van de Koppel, Herman, Bakker & Bouma 2007 Biomechanical warfare in ecology; negative interactions between species by habitat modification. Oikos 116:742-750

the planning. ‘We’ve become involved in this study, to show the biologist’s point of view and to get our share of information on models, tools, and ways of interpretation.’ Another issue is the monitoring of vast natural areas like the coastal seas. How can you scale up from only a few samples to a survey covering the whole area? That’s a policymaker’s brainteaser. ‘As well as needing automatic continuous sampling stations, the field of monitoring – at least in the Netherlands – also needs some fresh scientific input. As we have at our disposal remote sensing techniques and a huge and still growing database of samples, we’re ideally placed to take care of this.’ (5) Last but not least, the department is involved in some Big Science projects centred on socially relevant issues. One such project is examining whether salt marshes can help reduce the impact of tides in a world of rising sea levels.

Contact: +31-113-577 475 / 300

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'Unexpected relationships in food webs are the most interesting' The Department of Aquatic Food Webs studies the interactions of freshwater plankton – minuscule aquatic animals and plants – to find out how their interactions affect the entire freshwater ecosystem. How can the knowledge gained be used to restore lakes? ‘In lake restoration you see more failures than successes. We’re proposing some alternative measures.’


quatic ecology is core business for Ellen van Donk’s department, combining an evolutionary and a functional orientation. Algae form the basis for many food webs. ‘Biotic and abiotic processes influence these webs. That’s the theme connecting our research,’ she elucidates. We are witnessing many changes on our planet. What could happen to our freshwater ecosystems? As Van Donk explains, ‘To answer that question, you first have to find out how the interactions are shaped. You can experimentally put stress on the system, simulating global change, for instance.’ A simulated six degrees warmer climate throws water fleas out of sync with

their food supply (2). In spring, their resting eggs are triggered to hatch by a specific daylength, but the algae they feed on react to rising temperature and so start to grow earlier. Without water fleas to eat them, the algae grow prolifically. As a result, the typical clear water phase does not occur and underwater plants receive less light. QUALITY FOOD

A changing climate can also influence food in another way. ‘The clue lies in nutrients like phosphorus and carbon and the ratio between them,’ says Van Donk. Environmental measures are reducing the

Another line of research is experimental evolution. The department’s scientists used a fungal parasite and its host, a star-shaped diatomic alga, to study genetic adaptation. In monocultures, the host had a greater risk of suffering a fungal epidemic because all individuals were equally susceptible and the attacking pathogen could quickly adapt (1). And while we’re on the subject of attacks, defences induced in prey by the presence of predators, as opposed to permanent defences, prevent strong ecosystem fluctuations and extinctions of predators. In particular, inducible defences in herbivores have an overriding effect on the balance of a food web (5). According to Van Donk, ‘Dutch researchers are well

known for linking actors in food webs up to the second and third levels, and we’re experts on the links in lakes.’ GONE GREEN Basic research also has a practical side, like restoring lakes that have gone murky green because of excess nutrients. Why are restoration failures more common than successes? ‘We’ve looked into this and propose three alternative measures,’ says Van Donk. First of all, you could introduce zebra mussels (3).They keep algae and cyanobacteria in check by eating them. These mussels only need hard substrates to grow on. Under the European Water Framework Directive, they will soon be introduced into several Dutch lakes. Secondly, you can create islands to reduce the wind fetch and waves and therefore also the resuspension of bottom particles. Lastly, you could allow more fluctuations in the water level, to get more aquatic plants and less resuspension. ‘Some discoveries are made by chance,’ Van Donk muses. After layers of toxic cyanobacter ia suddenly vanished from tanks in the lab, the scientists found they were being devoured by the special alga Ochromonas without any problems. ‘We’re now investigating whether Ochromonas can help inhibit beginning cyanobacterial blooms. For me, it’s unexpected relationships like this that are the most interesting.’

Publication highlights 1. De Bruin,Ibelings, Kagami, Mooij & Van Donk 2008 Adaptation of the Fungal Parasite Zygorhizidium planktonicum During 200 Generations of Growth on Homogeneous and Heterogeneous Populations of Its Host, the Diatom Asterionella formosa. Journal of Eukaryotic Microbiology 55:69-74 2. De Senerpont Domis, Mooij, Hülsmann,Van Nes & Scheffer 2007 Can overwintering versus diapausing strategy in Daphnia determine match-mismatch events in zooplankton-algae interactions. Oecologia 150:682-698 3. Gulati, Dionisio Pires & Van Donk 2008 Lake restoration studies: failures, bottlenecks and prospects of new ecotechnological measures. Limnologica 38:233-247 4. Ibelings, Havens, Codd, Dyble, Landsberg, Coveney, Fournie & Hilborn 2008 Ecosystem effects of harmful cyanobacterial blooms. Advances in Experimental Medicine and Biology 619:657-677 5. Van der Stap,Vos,Verschoor, Helmsing & Mooij 2007 Induced defenses in herbivores and plants differentially modulate a trophic cascade. Ecology 88:2474-2481 6. Van Donk, Hessen,Verschoor & Gulati 2008 Re-oligotrophication by phosphorus reduction and effects on seston quality in lakes Limnologica 38:189-202

Contact: +31-294-239 353 /300

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phosphate (P) concentration in water, while more CO2 in the atmosphere is causing the carbon (C) concentration in the water to rise, because more CO2 gas dissolves. The outcome could be a higher C to P ratio in algae, which makes them less nutritious for their grazers. The team analysed all available data from lakes (6). Luckily, the only susceptible lakes were small deep lakes with stratified water, and shallow lakes rich in organic material. The C to N (nitrogen) ratio is also affected by climate change. Cyanobacteria are notorious for their toxins. The role of these toxins is still largely unknown (4), but a lot of N is needed to produce them. So, a change in the nutrient ratio will influence this process too.

‘Does microbial diversity matter? That's the question’ ‘We integrate the biodiversity of micro-organisms with their functioning in biogeochemical cycles, asking “what is a species doing?”’ This yields insights into the function of microbial biodiversity. Most of the department’s research is conducted in wetlands. Here, all sorts of functional groups of micro-organisms occur within micrometres of each other.


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ccording to head of department Riks Laanbroek, ‘All the processes on this planet were invented by micro-organisms, but finding all these different organisms is really hard’. Take the sulphatereducing micro-organisms: ‘Seawater contains a lot of sulphate, and the micro-organisms are evident here, but we had a hunch that they should be around in non-marine ecosystems as well.’ NIOO scientists started to study this group in floodplains, using microarray, fatty-acid, and their purpose-built so-called DGGE methods. The more molecular techniques they master, the deeper microbial ecologists can probe. Surprisingly, the diversity proved far more extensive than expected(3). It turns out there are almost as many sulphate-reducing species close to the rivers as there are in the sea. These findings are also of interest to organic chemists and conservationists, because in wetland soils rich in iron phosphates the phosphates are released when iron binds to sulphide produced by these microbes. The result is eutrophication. If sulphates are absent, the micro-organisms probably switch to an alternative fermentation. The resulting excess hydrogen is dumped in the form of the greenhouse gas methane. GREENHOUSE GAS Is microbial diversity important, or doesn’t it matter because several species are able and available to do

exactly the same as a declining species? ‘That’s the question,’ says Laanbroek. ‘Redundancy in functionality is abundant in micro-organisms and makes ecosystems stronger. In a study in a tidal freshwater marsh, we saw a nice example of so-called niche differentiation.’ NIOO scientists found that what largely determined which bacteria were responsible for ammonia oxidation at a certain location was not the presence of plants, but the height relative to low tide(2). Ammonia was oxidised everywhere, yet by different species. ‘But we have definitely not seen the last evidence in this debate. A second study, on methane-producing bacteria on roots, showed that methane production depends greatly on the soil characteristics(1).’ Methane production when rice was grown on soil from rice fields was much more rapid and much higher than when rice was grown in soil from a river bank in which the rice roots encountered totally different soil bacteria. As methane is a potent greenhouse gas, this finding is important. Laanbroek has a message: ‘When debating climate change it is important to remember that all models to estimate methane emissions are fairly crude. They do not consider the biodiversity of the microorganisms conducting the processes, even though this is a decisive factor for methane production and emission.’ The ammonia oxidisers found in the first-mentioned project are not particularly harmless. Some of them


Another line of research investigates phytoplankton: for example, how satellite images can be used to monitor cyanobacterial blooms, and what is the impact of viruses on phytoplankton. Hardly any research had been done on the importance of viral infections in freshwater, as most virus researchers focused on the sea.

Publication highlights 1. Conrad, Klose, Noll, Kemnitz & Bodelier 2008 Soil type links microbial colonization of rice roots to methane emission. Global Change Biology 14:657-669 2. Laanbroek & Speksnijder 2008 Niche separation of ammonia-oxidizing bacteria across a tidal freshwater marsh. Environmental Microbiology 10:3017-3025 3. Miletto, Loy, Antheunisse, Loeb & Bodelier 2008 Biogeography of sulfate-reducing prokaryotes in river floodplains. Microbiol Ecol 64:395-406 4. Tijdens,Van de Waal, Slovackova, Hoogveld & Gons 2008 Estimates of bacterial and phytoplankton mortality caused by viral lysis and microzooplankton grazing in a shallow eutrophic lake. Freshwater Biology 53:1126-1141

A team led by NIOO found that in winter, viral infections reduced the filamentous cyanobacterial and other bacterial growth by almost 100% (4). This shows the potential importance of viral infections for bacteria and algae in freshwater bodies like the shallow lakes in the Netherlands. In spring, the main cause of death for cyanobacteria was grazing by minuscule zooplankton. Laanbroek’s message for freshwater managers is that ‘more knowledge of viral attack and grazing could help prevent cyanobacterial blooms.’ Contact: +31-294-239 336 / 300

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emit laughing gas (N2O) as a by-product, an even more potent greenhouse gas than methane – and almost 300 times more potent than CO2. ‘What we do not know is whether certain ammoniaoxidising communities are more likely to produce laughing gas than others.’

‘A swan need not be as picky as a cold-blooded lizard’ ‘The spread of bird flu and the role of wild birds in this have become major research themes in recent years. Our research has even been discussed in parliamentary questions.’ But the scientists’ focus remains basic ecology: they seek to understand and predict species’ interactions.


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ne of the department’s main goals is to clarify the role of animals in the dispersal of other organisms such as seeds and viruses – including the ensuing effects on individual species and communities (4,5,6). ‘There are lots of anecdotes, but we want to find sound evidence to support them,’ says head of department Marcel Klaassen. FLU IN THE WILD

‘The most striking result of our bird flu pilot study in migrating Bewick’s swans was that low-pathogenic strains reduced feeding rates and delayed the migration by one month in the wild (6). In the lab, no one had ever seen any effect from such strains in an infected animal.’ Flu symptoms show up sooner in a hard-working animal enduring bad weather, which is why field experiments are vital to understanding the effects of flu. ‘In 2008 we started a field experiment with infected swans. Using transmitters we track them to find out if they spread the low-pathogenic bird flu virus and where they spread it to.’ Klaassen continues: ‘People are scared of migrating birds because they might be carrying disease that could spread to poultry and to people. Without solid clues, extreme measures are taken, like shutting all poultry indoors, or killing the migrating birds – or even all birds – in a certain area. But there’s been little fundamental research on the role of wild birds. My message for the worriers is that the only remedy against unfounded fears is scientific research.’

Pink-footed geese have issues of their own. How can migratory birds like this journey safely? They need stop-over sites along the way to refuel, but farmers don’t like them grazing their lush pastures (1). In spring, farmers in Norway used to actively scare off birds flying from Western Europe to Svalbard to breed. ‘In 2006, working in an international team, we were able to model the consequences and estimate the resulting decline in the population of pinkfooted geese.’ Now, Norwegian farmers are

Publication highlights 1. Klaassen M, Bauer, Madsen & Tombre 2006 Modelling behavioural and fitness consequences of disturbance for geese along their spring flyway. Journal of Applied Ecology 43:92-100 2. Klaassen M, Bauer, Madsen & Possingham 2008 Optimal management of a goose flyway: migrant management at minimum cost. Journal of Applied Ecology 45:1446–1452 3. Klaassen M & Nolet 2008 Stoichiometry of endothermy: shifting the quest from nitrogen to carbon. Ecology Letters 11:785-792 4. Klaassen R & Nolet 2008 Persistence of spatial variance and spatial pattern in the abundance of a submerged plant. Ecology 89:2973-2979 5. Pollux, Ouborg,Van Groenendael & Klaassen M 2007 Consequences of intraspecific seedsize variation in Sparganium emersum for dispersal by fish. Functional Ecology 21:1084-1091 6. Van Gils, Munster, Radersma, Liefhebber, Fouchier & Klaassen M 2007 Hampered foraging and migratory performance in swans infected with low-pathogenic avian influenza A virus. PLoS ONE 2:e184

reimbursed for their feathered dining guests and no longer need to resort to scaring them off. ‘This is partly thanks to our research.’ There are potentially many things you can do to help migrating birds, but they all cost a lot of money. ‘You can use ecological models to make sound conservation and economic decisions on optimal flyway management,’ enthuses Klaassen (2). DRAMATIC WARMTH Klaassen is even more enthusiastic about the dramatic new insight gained into the evolution of endothermy (3). Generating heat to keep your blood warm costs a huge amount of energy, obtained from eating lots of food. But plant-eating endotherms not only eat much more than their cold-blooded counterparts, they can also choose from a far greater variety of plants. As Klaassen puts it, ‘A swan does not have to be as picky as a lizard.’ He noticed that many scientists evaluated food quality in terms of nitrogen (N). As most of the body consists of proteins built from N, this seems logical. But Klaassen had a feeling that the element carbon (C), linked to energy requirements, was at least as important as N. ‘A cold-blooded herbivore has to select plants with high-N content only. But it’s a piece of cake for a warm-blooded animal to meet its protein needs just by eating lots of leaves and burning the excess carbon to get warm.’ So endothermy might be a useful by-product of herbivorous guzzlers, rather than the engine driving the evolution of fastrunning predators. Klaassen: ‘I consider this to be a fundamental contribution to our perception of plant–animal relationships.’

Contact: +31-294-239 317/300

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‘Our data on the ecological effects of climate change is also important to politicians’ Evolutionary ecology, behavioural biology, and population ecology constitute the backbone of the Department of Animal Population Biology. The main model species is the great tit, a well-known European songbird. It fuels our knowledge of life history strategies, parental conflicts, and animal personalities. ‘Apart from its behaviour, an animal’s personality influences things like its chances of survival or a cheating partner.’ But basic biology also yields insights into social concerns, like climate change.

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e’ve always been a group working in several fields of study.That’s also one of our strengths,’ asserts Marcel Visser, head of the department. ‘Integration comes naturally. Physiology and ecogenomics go together with ecology very well.’ Many of the recent developments in ecology are reflected in the department’s research, with a focus on the mechanisms behind life history traits and the growing importance of genomics to unravelling such ecological questions. Collaboration with other disciplines is essential. ‘We led a consortium of endocrinologists and ecologists who study avian reproduction, subsidised by the European Science Foundation, and connected to American NSF and Canadian NSERC networks to widen the span of our work. That worked very well.’

LATE BIRDS A main area of research is the ecological effects of climate change.Visser has also received support from a national NWO-VICI grant for this work. Climate change can, for instance, cause a mistiming between an animal’s needs and the availability of its food in spring, the breeding season. This situation is probably widespread. ‘For the first time, we could prove

there was a link between serious mistiming due to climate change and diminishing population numbers,’ says Visser. The scientists demonstrated this in the pied flycatcher, a long-distance migratory bird (1). For several decades, spring has started earlier and earlier in Western Europe. Now the bird is late when it arrives from its wintering grounds in Africa and it largely misses the ‘caterpillar peak’, the main food source for its chicks. According to Visser, ‘people often said, mistiming – so what? But we have now shown it can produce a detrimental effect.’ The work on the effects of a warming world has a political twist. ‘What rise in temperature can ecosystems withstand? We have to be able to say: with 2 degrees it’s all right, but with 6 degrees we will lose half of the species. So, what will the target be? Our research helps to answer these more applied questions,’ explains Visser. He outlined the route to assessing the consequences on biodiversity (5). ‘This is important for biologists as well as politicians.’ First we must develop the means to predict the rate of micro-evolutionary adaptations for different climate scenarios. This data can then be used to estimate

BEGGING OFFSPRING On Vlieland, an island in the Dutch Wadden Sea, in an experiment that was unique in size and duration, the department tested whether the evolutionary dynamics of a complex trait can be predicted (3). They artificially selected for clutch size in a wild

Publication highlights 1. Both, Bouwhuis, Lessells & Visser M E 2006 Climate change and population declines in a long-distance migratory bird. Nature 441:81-83 2. Lessells 2006 The evolutionary outcome of sexual conflict. Phil Trans Roy Soc B: Biological Sciences 361:301-317 3. Postma,Visser J & Van Noordwijk 2007 Strong artificial selection in the wild results in predicted small evolutionary change. Journal of Evolutionary Biology 20:1823-1832 4. Van Oers, Drent, Dingemanse & Kempenaers 2008 Personality is associated with extrapair paternity in great tits, Parus major. Animal Behaviour 76:555-563 5. Visser M E 2008 Keeping up with a warming world; assessing the rate of adaptation to climate change. Proc Roy Soc B: Biological Sciences 275:649-659

great tit population. Evolutionary changes proved to be small, due to environmental differences, but predictable. Visser: ‘What is unique about the NIOO is that we can carry out a large-scale experiment like this for eight years. That really is not possible at universities.’ The department also works on parental conflicts, both between parents and their offspring and among parents about care for the young. In the latter case, collateral damage is in neither sex’s interest, and this gives rise to harm-reducing adaptations (2). ‘Lately, we have produced models to predict parental investments, besides field work in the woods replaying begging calls from chicks to parents.’ This project was combined with one on ‘begging behaviour’ in humans for a national programme on Evolution & Behaviour. Another area where bird studies are linked to studies of humans is personalities. Two basic types exist in almost all animals, including humans: cautious scouts and fast, bold individuals. Personality has many consequences in life. For example, partner choice is dependent on personality. The scientists also found a link between personality and extra-pair paternity (4). In great tits, there is a greater chance of neighbours secretly fathering part of the brood when partners have the same personality. ‘Extra-pair mating can help explain how different personalities coexist sustainably.’

Contact: +31-26-4791 253 / 111

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population viability and biodiversity loss, to be implemented in policies.

‘We have to abandon the concept that biodiversity benefits from stability’ The Department of Multitrophic Interactions is looking for the master factor below as well as behind the interactions they study. ‘The soil plays a significant role in every pattern and process you see aboveground. We have to take the soil’s key part into account in nature management, in biological crop production, and in biological invasions.’


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n Wim van der Putten’s department, many other domains are merged into the new field of multitrophic interactions, like plant and chemical ecology, entomology, nematology and molecular biology. ‘We need all these to disentangle the intricate interactions between plants, herbivores, and the herbivores’ enemies. We want to link the subecosystems aboveground and belowground to get the whole relevant picture.’ CHEMICAL PHENOTYPE The department’s first line of work focuses on cues and mechanisms. Plants organise the communication between belowand aboveground insects by conveying signals ‘like phone lines’ (4). Scientists are now able to explore ever more complex interactions and communities. ‘The traditional way of thinking, from genotype to phenotype, is giving way to one supported by ecogenomics and metabolomics: gene activity resulting in a chemical phenotype,’ explains Van der Putten.The chemical phenotype provides insights into a suite of multitrophic interactions. For example, within the plant species Barbarea vulgaris, a polymorphism in one gene directs the production of two glucosinolates, the most important defensive compounds in crucifers. Pieris rapae caterpillars are specialist herbivores and can cope with both types, whereas caterpillars of the Mamestra moth are clearly inhibited by one (2). Mamestra is a generalist that can feed on a number of

species, but it cannot handle glucobarbarin, often causing death. Van der Putten is fascinated: ‘A onegene difference determines how a plant ‘treats’ its herbivores!’ HERB GARDEN The research community’s focus on species diversity has shifted towards functionality of diversity, which is the department’s second theme. ‘In one of the shortest papers we’ve ever written, we explain why biodiversity experiments always yield the same enforced results’ (1). The traditional experimental setup, of big, hand-weeded plots of unnatural plant communities, shows that the more species there are, the more stable is the ecosystem. ‘Our alternative setup differs in one essential way. We have been following sown and unsown, spontaneously colonised plots on former agricultural fields for over 10 years.’ The differences in species composition are persistent, but the existing species traits are converging. More importantly, in the naturally colonised plots, the highest biodiversity coincides with the lowest stability. The traditional conclusion proved to hold for sown communities only. Van der Putten: ‘We have to abandon the concept that biodiversity benefits from stability. Dynamics in vegetation promote diversity.’ Another study in the realm of ecosystem development is investigating the feedback between plants

WARM WELCOME? As range-expanding plants are currently a hot issue, the third research theme has evolved from classic to climate-driven biological invasions. Increasing numbers of species are entering the Netherlands from southern Europe. The department has studied which exotic plant species have established in a riparian nature reserve in the last few warmer decades (3). ‘We compared the exotics to relatives native to the country. Both were exposed to soil pathogens and aboveground herbivores, including a locust that has not co-evolved with any of these plants.’ The exotic plants showed a significant advantage over natives: enemies aboveground and belowground exercise less control over them. Eurasian exotics yielded the same results as ‘true’ exotics from other continents, which suggests that species shifting to higher latitudes or altitudes can be potential invaders. Van der Putten adds: ‘Our novel finding was wellreceived. A review of the Faculty of 1000 Biology awarded it the high score of ‘must read’.’

Publication highlights 1. 2.




Bezemer & Van der Putten 2007 Diversity and stability in plant communities Nature 446:E6-8 Van Leur,Vet,Van der Putten & Van Dam 2008 Barbarea vulgaris Glucosinolate Phenotypes Differentially Affect Performance and Preference of Two Different Species of Lepidopteran Herbivores. J Chem Ecol 34:121-131 Engelkes, Morriën,Verhoeven, Bezemer, Biere, Harvey, McIntyre,Tamis & Van der Putten 2008 Successful range-expanding plants experience less above-ground and below-ground enemy impact. Nature 456:946-948 Soler, Harvey, Bezemer & Stuefer 2008 Plants as green phones. Novel insights into plant-mediated communication between below- and above-ground insects. Plant Signaling & Behavior 3:519-520 Kardol, Bezemer & Van der Putten 2006 Temporal variation in plant-soil feedback controls succession. Ecology Letters 9:1080-1088

Contact: +31-26-4791 203 / 111

33 progress report

and soil organisms (5). ‘Earlier models did not consider these feedbacks. We have been able to prove experimentally that soil organisms affect plant community assemblage.’ On recently abandoned land the feedback is negative, but later in the succession it becomes positive – which encourages the development and conservation of target vegetation.

‘Certain bacteria are very useful to have around’ Bacteria and fungi that live in the soil or on decaying wood interact a lot, positively as well as negatively. It is these interactions and their consequences that constitute the central research theme for the Department of Terrestrial Microbial Ecology. But the origin and the significance of microbial biodiversity also claim a fair share of the scientists’ attention, especially if they happen to discover useful traits. ‘Valorisation is very important. We’re working on a number of products.’

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icrobial ecology is actually a fairly immature discipline, because you can’t detect the objects of study that easily,’ says head of department Hans van Veen. So, the field is strongly oriented on methodology. ‘The conceptual frameworks we use are mostly derived from macro ecology, but we’re now at the stage of formulating new microbiological ones.’ The important developments are in the realm of genomics. ‘Techniques geared towards microbial ecology have now earned their place in our toolbox. The first PhD theses based on genomic analyses recently appeared. Another fascinating development is the research on single cells or small populations within their own specific niche in the soil.’ This research will shed light on some of the major questions in ecology – about the origin and function of the huge biodiversity of microbes in the soil, often said to be the richest source of biodiversity on earth. ‘Our researcher George Kowalchuk has been awarded a prestigious VICI grant to tackle exactly these questions.’ ANTI-FUNGAL

‘Our research on bacteria–fungi interactions has proved to be very successful, particularly that on the fungus-eating bacterium Collimonas.’The department discovered the species in dune soil only a few years ago and has been studying its unique ecology ever since (e.g. 4). Some of the findings on the special

Publication highlights 1. De Boer,Wagenaar, Klein Gunnewiek & Van Veen 2007 In vitro suppression of fungi caused by combinations of apparently non-antagonistic soil bacteria. FEMS Microbiol Ecol59:177-185 2. Drigo, Kowalchuk,Yergeau, Bezemer, Boschker & Van Veen 2007 Impact of elevated CO2 on the rhizosphere communities of Carex arenaria and Festuca rubra. Global Change Biology 13:2396-2410 3. Folman, Klein Gunnewiek, Boddy & De Boer 2008 Impact of white-rot fungi on numbers and community composition of bacteria colonizing beech wood from forest soil. FEMS Microbiol Ecol 63:181-191 4. Höppener-Ogawa, Leveau, Smant, Van Veen & De Boer 2007 Specific detection and real-time PCR quantification of potentially mycophagous bacteria belonging to genus Collimonas in different soil ecosystems. Appl Environm Microbiol 73:4191-4197 5. Yergeau, Schoondermark-Stolk, Brodie, Déjean, DeSantis, Gonçalves, Piceno, Andersen & Kowalchuk 2008 Environmental microarray analyses of Antarctic soil microbial communities. ISMEJ online

eral damage on the fungi. ‘Until now, people have always searched for a single organism for biological pest control. This finding opens up gigantic new possibilities, including for currently untreatable pests.’ Many bacteria and fungi interact on decomposing wood in forests. ‘This is a very new field,’ says Van Veen. ‘Wood consists largely of lignin, and only a handful of specialised fungi are able to decompose it by excreting enzymes. These turn lignin into a number of easily decomposable nutritious compounds. At this point, competing bacteria can snatch the food from the fungi. The fungi fight back by making their environment unpleasant for the bacteria. In our study, we found that whiterot fungi can out-compete wood-inhabiting opportunistic bacteria.’ (3) But certain bacteria are useful to have around: for instance the one that can bind the limitedly available nutrient nitrogen. ‘This makes the fungi happy too.’ BACK TO THE ROOTS

Climate-change induced effects in the soil are another line of study. A NIOO team has investigated the effect of an enhanced level of atmospheric CO2 on the microbes surrounding plant roots(2). These so-called rhizosphere communities are influenced via the plants. Similar studies are being carried out on the effects of genetically modified plants on microbial communities and their functioning.You thought the Antarctic soil was barren? Wrong! The department has analysed the microbial diversity and the changes taking place in it with special ‘phylochips’ carrying a large collection of microarrays of genetic information (5). Van Veen concludes, ‘This ecogenomics project is one of the first to use microarrays on a large scale. Policy makers, in particular, would welcome such a tool, fort determining the status of the soil.’ Contact: +31-26-4791 243 / 111

35 progress report

compounds produced by Collimonas are soon to be applied within a small spin-off venture. The greater goal is the discovery and exploitation of biologically active compounds from as yet unknown bacteria. Other interactions are also researched in the lab. While studying soil suppressiveness, the soil’s ability to suppress the growth of ‘unwanted’ organisms, the team made an exciting discovery. Two bacteria that on their own had no effect on fungi were able to inhibit fungal growth totally when applied together (e.g. 1). How is this possible? The department’s scientists think the bacteria react to each other’s presence, thereby inflicting collat-

Business and finance


k€ 18,000 16,000 14,000

BUDGET The Netherlands Institute of Ecology (NIOO-KNAW) has an annual income of approximately 16 million euros (Fig. 1). Approximately 70 % of its funding is from the Royal Netherlands Academy of Arts and Sciences (KNAW). External funding is stable, at around 30 % of the total income. The sources of this funding include institutions such as the Netherlands Organization for Scientific Research (NWO) and the European Union (Fig. 2).

12,000 10,000 8,000 6,000 4,000 2,000 0 2004


direct funding (KNAW) research funds (NWO)




contracts (EU and other) other

Fig. 1.Total annual income (in thousand euros).


100% 90% 80%

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STAFF In 2008, NIOO employed 225 people or 199.2 full-time equivalents (FTE), made up of 101 women and 124 men (Fig. 4). The percentage of female employees has risen slightly. In addition, some staff are on secondment from other organisations.

On average, 54% of the entire (FTE) staff are scientists and 46% are support staff (e.g. analysts/ research assistants and service department employees). The percentage of people with longterm contracts has remained fairly consistent: around 59% (Fig. 5).

70% 60% 50% 40% 30% 20% 10% 0%



direct funding (KNAW) research funds (NWO)




contracts (EU and other) other

Fig. 2.The contribution of the two most important external funding organisations – the Netherlands Organization for Scientific Research (NWO) and the European Union (EU) – to the NIOO budget is considerable.


100% 90% 80% 70% 60% 50% 40%

As an internationally-oriented research institute, NIOO employs people of many nationalities (Fig. 6).

30% 20% 10% 0%

2004 Personnel Material costs

Fig. 3.








>60 51-60 41-50 31-40 21-30 <21 0








40 number

Women Men Fig. 4.The age distribution of NIOO staff is similar for both sexes. In the cohorts above the age of 45 there are significantly fewer women.The distribution has been calculated as an average for the years 2006-2008.


fte 120 100 80 60

20 0




Assistant Research Fig. 5.The number of staff with fixed-term contracts was 95 people (42%) in 2008.The figures for 2006 and 2007 are comparable.










Dutch non-Dutch Fig. 6. NIOO is an international stronghold. About one third of all new NIOO employees hired in the period 2006-2008 were non-Dutch.The percentage was even higher among the scientists.

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Scientific publications



1200 1000


800 100

600 400


Results found: 598

Sum of the Times Cited: 3,178

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the ocean. PNAS 103:12317-12322. 2. 101 x: Both, C., S. Bouwhuis, C.M. Lessells, population declines in a long-distance migratory bird. Nature 441:81-83. 3. 72 x: Grimm, V., U. Berger, F. Bastiansen, S. Eliassen, V. Ginot, J. Giske, J. Goss-Custard, T. Grand, S.K. Heinz, G. Huse, A. Huth, J.U. Jepsen, C. Jorgensen, W.M. Mooij, B. Muller, G. Pe'er, C. Piou, S.F. Railsback, A.M. Robbins, M.M. Robbins, E. Rossmanith, N. Ruger, E. Strand, S. Souissi, R.A. Stillman, R. Vabo, U. Visser and D. L. De Angelis 2006. A standard protocol for describing individual-based and agent-based models.

1. 110 x: Wuchter, C., B. Abbas, M.J.L. Coolen,

Ecological Modelling 198:115-126.

L. Herfort, J. van Bleijswijk, P. Timmers, J.J. Middelburg, S. Schouten, and J.S.S. Damste 2006. Archaeal nitrification in

NIOO database 2008 2007 2006

234 228 193


Web of In journals Science impact factor > 3 201 214 183

75 116 63




Average Citations per Item: 5,31

h-index: 21

Fig. 1. The Web of Science citation report on NIOO’s publications.

The three articles with the highest citation rates (June 2009) are:

M. Strous, E. Teira, G.J. Herndl,







and M.E.Visser 2006. Climate change and

CITATIONS The citation report from the Web of Science on the 598 papers published in the period 2006-2008 totals 3178 citations (Fig.1). On average, this is 5.31 citations per item, which leads us to an ‘h-index’ of 21 (21 papers have been cited at least 21 times).


1600 1400



he number of scientific papers published by the Netherlands Institute of Ecology (NIOO-KNAW) has been steadily increasing (Table1). The institute is currently collaborating with thirdparty institutions from 53 different countries, and this list too is getting longer. Of the 598 papers published in the last three years, 387 were written in international collaboration. About one-third of all NIOO publications were published in journals with an impact factor of 3 or higher. For comparison, the aggregate impact factor of journals in the subject category ‘ecology’ is 2.502, for ‘plant sciences’ 2.286, and for ‘ornithology’ 1.104 (JCR 2007).

% in journals impact factor > 3

Collaborating institutions

32 59 35

273 250 217

Table 1. The number of NIOO’s scientific peer-reviewed publications, and the extent of collaboration.

(ESI) NIOO is positioned mainly in the two subject fields of ‘Plant & Animal Science’ and ‘Environment/ Ecology’. ESI figures rank papers in a 10-year overview. The baseline of 1998-2008 for Plant & Animal Science is 6.90 citations per paper and 9.50 citations for Environment/ Ecology. NIOO’s score for Plant & Animal Science is 14.31 citations per paper and 17.40 for Environment/ Ecology. The NIOO score is thus about twice as high as the world average. This is also reflected in the Science and Technology Indicators produced by NOWT (The Netherlands Observatory of Science and Technology). They specify 1.35 as a citation impact factor for the NIOO, with 1 being the world average. When the focus is on publications authored in international collaboration, NIOO has an even higher score of 1.43.


Popularising science


MEDIA AND MORE One direct route to publicity is media reports and the use of press releases to garner the attention of journalists. Table 1 sums up some of the results from recent years, showing a generally increasing amount of news coverage of the institute’s research. In a country as small as the Netherlands this is a good score for an institute which performs a lot of basic research. NIOO’s scientists and public information officer also write popular science articles for magazines and websites. A specific site in which NIOO collaborates is or, focussing on the North Sea and its coastal areas. Our own website contains information at varying levels of difficulty, tailored to diverse target audiences. In 2007 it was visited by more than 150,000 unique visitors, with more than 2.1 million page views in total (excluding known bots). The website

was relaunched in December 2008. Please let us know if you are looking for information we have not provided here. IN PERSON Personal performances are another way of providing information, and can be very successful. The number of people you reach directly is smaller, but the sharing of knowledge and understanding is more intense and therefore more rewarding. NIOO’s open lab days, held almost every year (www.nioo., always draw large numbers of people.The 2008 edition at our research centre in Heteren welcomed close to 800 visitors in a single day. Furthermore, NIOO YEAR Total number of media reports - newspapers/magazines/websites - radio - TV Number of general press releases Average news coverage (per week)

is involved in delivering lectures, building presentations at science or nature festivals, giving workshops to teachers, organising school projects, and advising museums on exhibitions. Symposia and workshops are appropriate for specific groups of stakeholders. In 2007, the fiftieth anniversary of water ecology in the Netherlands and 15 years of NIOO were celebrated with a symposium and an open day to reach both a specific and a general audience. The full-throttle popularisation of science will always involve a combination of ‘broadcasting’ and ‘narrowcasting’. Contact: or





≥287 / year

≥350 308 25 17 12 6.7 x

≥412 375 27 10 18 7.9 x

≥272 ≥345 / year 242 15 15 14 5.2 x 6.6 x

5.5 x


Table 1. Analysis of NIOO news events. The average news coverage was calculated as the total number of media reports divided by 52 weeks.

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or the layman, scientific publications and presentations can be difficult to fathom. Still, it’s vital to communicate important research results to a wider audience. Especially when the science of ecology is concerned, there can be many useful links to practical applications and to sustainability. Therefore, NIOO highly values the popularisation of science. It isn’t always easy to translate highly detailed science into everyday wording and straightforward quotes. Different media are employed for different causes; here we’d like to showcase some of them.

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40 Artist renderings by Claus en Kaan Architecten

NIOOâ&#x20AC;&#x2122;s new sustainable building


n 2010, the two NIOO-KNAW research centres in Heteren and Nieuwersluis will move into a new sustainable building in the city of Wageningen.The aim is to build the most sustainable research laboratory in the Netherlands.The well-known Dutch architectural firm Claus en Kaan Architecten designed a glass-rich complex that will house about 160 employees plus students and (international) guests. The grounds, covering four hectares, will offer offices, laboratories, greenhouses, experimental ponds and gardens, a technical workshop, and aviaries.

C2C The leading principle in the design is to be innovatively sustainable in as many ways as possible, which was the explicit wish of NIOO’s management. The acclaimed Cradle to Cradle (C2C) idea, from the book by William McDonough and Michael Braungart, constitutes an important source of inspiration. Instead of materials that are used only once and considered to be waste afterwards (cradle to grave), they can be designed to be re-used or ‘up-cycled’ to make new, high-quality products that are at least as useful as their original components – not leaving any wasteful residues. Waste = food. NIOO likes to be part of a circular economy.

Contact: or

41 progress report

PRACTICAL TRANSLATION For the new NIOO building these ideas translate into closing the cycles for water, energy, nutrients, and materials. In practice, this means lots of daylight, numerous outdoor views, natural air flows, experimental green roofs, sustainable energy (including solar energy and energy derived from the building’s own waste flows), the use of algae to recover nutrients (such as phosphorus and nitrogen), separate water systems, sustainable and ‘functionally flexible’ materials, the encouragement of biodiversity on the grounds and in the surrounding areas, and a design that takes full account of the needs of those who work in the building. One eyecatching pilot project is very deep and efficient warmth/cold storage in the subsoil. Others are using native prickly bushes as ecological fences and toilets that can separate valuable energy and nutrients. In the period 2006-2008 many preparations were concluded, resulting in the laying of the foundation stone (in Dutch: ‘het slaan van de eerste paal’) on May 26, 2009.

Progress portal: Internet links To learn more about NIOO, please visit The links there will take you to information on:

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- Staff (contact details and personal pages) - Scientific projects - Scientific publications (searchable database and detailed lists by department) - Research centres and departments (homepages) - Press releases and other news - Updates to shared information - Job vacancies - And much more, including direct links to all publications mentioned in this report A digital version of this Progress Report, together with previous editions, is also available via the portal site. Please contact us to report any missing links, be it a practical issue or a scientific breakthrough!


ADDRESSES The NIOO locations in Nieuwersluis and Heteren will be relocated to Wageningen in 2010. Netherlands Institute of Ecology (NIOO-KNAW) Villa ‘Vijverhof ’ Rijksstraatweg 6 Nieuwersluis Correspondence to: P.O. Box 1299 3600 BG Maarssen The Netherlands Tel: +31 (0)294 239 312 / 300 Fax: +31 (0)294 232 078 e-mail:

NIEUWERSLUIS Centre for Limnology (NIOO/CL) Rijksstraatweg 6 Nieuwersluis Correspondence to: P.O. Box 1299 3600 BG Maarssen The Netherlands Tel: +31 (0)294 239 300 Fax: +31 (0)294 232 224 e-mail: HETEREN Centre for Terrestrial Ecology (NIOO/CTE) Boterhoeksestraat 48 Heteren Correspondence to: P.O. Box 40 6666 ZG Heteren The Netherlands Tel: +31 (0)26 479 1111 Fax: +31 (0)26 472 3227 e-mail:

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YERSEKE Centre for Estuarine & Marine Ecology (NIOO/CEME) Korringaweg 7 Yerseke Correspondence to: P.O. Box 140 4400 AC Yerseke The Netherlands Tel: +31 (0)113 577 300 Fax: +31 (0)113 573 616 e-mail:

the sediment was con stantly mixed by burrowing animals. A totally different world.’ ‘The diversity of marine bacteria is enormous: one millilitre of clear seawater can contain a million bacteria and 10 million viruses, even though the water is really clean. Multiply that by the number of

millilitres in the sea!’ ‘It will be a big step forward, to convince hydrologists

and engineers that there’s something living in their sandpit.’‘We have three recommendations

use biomanipulation, for lake restoration: create islands to reduce the wind fetch and resuspension of the sediment, and create or allow greater water-level fluctuations.’ ‘Even if all the animals vanished from Earth, the processes would keep on going – though if the only agents left were micro-organisms, many would take far longer. Micro-organisms are the bottom line in maintaining the cycles.’‘Our

research yielded new insights into the evolution of warmblooded animals. They possibly evolved as a by-

product of herbivory, and therefore not primarily as fast-running predators.’

‘The songbird great tit (Parus major) can serve as a model species for humankind.We

study bird personality its heri-tability, and its effect on fitness. Furthermore, we look at parent–offspring relationships

where interests are often conflicting.’ ‘Everything we eat, drink, or wear passes through the soil regularly. Not only nutrient cycles, but also interactions and communication pass through the soil.’‘Soil organisms

influence the species we see aboveground not only via nutrient cycles, but also by changing their communication signals. We have found a combination of two bacteria that have no effect in isolation, but control a

harmful fungus completely when they are applied together. Bingo!’ First there was a sea

Then, after the Cambrian ex-plosion and the burrowing revolution,the sediment

floor covered in microbial mats.

was con-stantly mixed by burrowing animals. A totally different world.’ ‘The diversity of marine bacteria is enormous: one millilitre of clear seawater can contain a million bacteria and 10 million viruses, even though the water

Multiply that by the number of millilitres in the sea!’ ‘It will be a big step forward,

is really clean.

and engineers that there’s something living in their sandpit.’‘We have three recommendations

to convince hydrologists

use biomanipulation, for lake restoration: create islands to reduce the wind fetch and resuspension of the sediment, and create or allow greater water-level fluctuations.’ ‘Even if all the animals vanished from Earth, the processes would keep on going – though if the only agents left were micro-organisms, many would take far longer. Micro-organisms are the bottom

Ecology is a bustling, dynamic field of research with many cutting edges, such as the evolving interfaces with molecular biology, geochemistry, and hydrodynamics. These and many other topics will be showcased in NIOO’s Progress Report, in which the new insights and discoveries of the past three years take centre stage. In this newly revamped, concise, and more personal edition we share our thoughts, knowledge, and advice with the world.