Our research can roughly be divided into three themes. Below you will find general information on these themes, but first we would like to provide you with some guidelines on how to select the right thesis project.
How to choose a thesis project?
The MSc thesis projects are clustered in research themes that cover the fields of interest of our lecturers, post-docs and PhD students. They are listed as supervisors. Many subjects are also suitable for a BSc thesis. New projects will be added to this site thoughout the year. Most projects are also included in the TIP-database http://tip.wur.nl. Length and content of a thesis project may be tailored to your wishes.
If you are interested in a particular thesis project you can contact the supervisor of the project directly. Alternatively, if you are interested in a theme but you cannot find a suitable project, you may consult the contact person of the theme. When you have difficulties choosing a theme, please contact Juul Limpens (email@example.com).
Apart from these research themes, you are of course allowed to formulate you own project. You can also do a thesis project at a research institute or a different university in the Netherlands or abroad, on the condition that the project and the supervision are of sufficient scientific quality (PhD supervisor). When you want to formulate your own project, please contact the contact person of a particular theme.
Start in time with looking for a thesis project and contacting people: preferably 3 to 9 months before the start of your project. Preparations for projects abroad take a long time. Some projects may require following an additional course.
Information on procedures around theses and internships and instructions for doing a thesis project are presented in the ‘Guidelines for preparing an MSc-thesis’. A hard copy can be obtained at the secretary’s office after registration for a thesis. The Guidelines also give an overview of prerequisite and recommended courses for a thesis PEN.
Theme 1 Environment and ecosystem functioning
Contact person: Elmar Veenendaal
Other supervisors: Monique Heijmans, Juul Limpens
Background: This theme covers our research on large-scale human influences on ecosystem functioning. Increased greenhouse gas concentrations in the atmosphere, climate change and nitrogen deposition strongly affect nutrient- and water cycling within ecosystems, plant growth, and competitive relations between plant species. Such effects may change vegetation succession and biodiversity. Conversely, the resulting changes in the vegetation can have important consequences for ecosystem processes such as biomass production, carbon sequestration and emission, evapotranspiration, erosion, absorption and reflection of solar radiation.
Research: We focus on the effects of climate change and N deposition on carbon sequestration and emission (Elmar Veenendaal), vegetation development and biodiversity. We particularly study the effects of changes in plant species composition on processes such as nutrient cycling, litter production, decomposition and mineralization. This involves mechanistic modelling of vegetation succession (Monique Heijmans). Understanding effects of global change and N deposition on biodiversity requires knowledge on how species respond to environmental changes (Juul Limpens). Effects of vegetation changes on the global radiation balance are studied in the Siberian tundra (Monique Heijmans, Ake Nauta).
Research objects: This research is done in heath lands, grasslands, fen meadows, raised bogs, and tundra’s.
Type of work: The research involves field observations, experimental work in field, garden or greenhouses, simulation studies on long-term dynamics of ecosystems
Theme 2 Biodiversity and ecosystem functioning
Contact person: Jasper van Ruijven; tel. 0317-484835
Other supervisors: Liesje Mommer, Elmar Veenendaal
Background: The biodiversity within ecosystems is an important aspect of the conservation value of ecosystems, because species rich communities are rare and many endangered species occur mainly in species rich communities. After many years of research the regulation of biodiversity is still poorly understood. How can we explain that 40 or more plant species of higher plants per m2 coexist in some communities, while other communities contain only a few species? How do species manage to survive under the pressure of competition, stress and disturbance? What circumstances are favourable to species richness and how can we promote and maintain or destroy these circumstances? The role of biodiversity in ecosystem functioning is even more obscure. Species richness could have important impacts on other ecosystem properties and functions such as resource use, biomass production, and resistance to invasions.
Several projects are united under this theme.
A. The importance of biodiversity for ecosystem processes
The rapid loss of species has inspired ecologists to investigate the importance of biodiversity for the functioning of ecosystems. For some ecosystem processes, such as primary productivity in grasslands, several experiments have shown loss of plant species is detrimental. This negative effect has been ascribed to a loss of beneficial interactions among species. However, we still do not fully understand which interactions and, more importantly, how they work. In addition, the importance of biodiversity for many other ecosystem processes, in different ecosystems, is unclear. For example, some experiments have shown biodiversity effects for decomposition of dead organic material, a crucial process driving C and N cycles and ultimately productivity, but other studies found no effect or even negative effects! So far, we cannot explain these conflicting results. New clever experiments are strongly needed.
B. Regulation of plant species richness
In nature conservation it is important to know which circumstances are important for the development of species rich communities and how can we restore species rich communities. The relation between species richness and nutrient availability is especially important, since nutrient availability is influenced unintentionally by environmental problems, like eutrophication, and agricultural practices, like drainage. It can also be manipulated deliberately by conservation management practices (like grazing, mowing, sod cutting, hydrological measures, and fertilisation). The highest species richness is usually found at intermediate levels of biomass production, as set by the availability of the most limiting nutrient. We investigate how species richness depends on biomass production, above-ground structure of the vegetation, identity and number of (co-)limiting nutrients. To determine which factors limit the various coexisting species we measure biomass nutrient concentrations and responses to fertilisation with separate nutrients in the field. To understand differences in response we investigate nutrient uptake efficiency and nutrient use efficiency in pot and water culture experiments in the greenhouse.
Theme 3 Nature conservation in agricultural and urban landscapes
Contact person: Prof.Dr. David Kleijn. E-mail
Other supervisors: Jeroen Scheper, Thijs Feijen
Background: Some of the most species rich European ecosystems have developed as a result of creation and/or prolonged and extensive use by mankind (e.g. chalk grasslands, sub-alpine meadows, walls). Currently, the diversity and species richness is being threatened seriously, especially in agricultural areas. Policy makers of EU and national governments s have recognised this and have started large-scale conservation initiatives. One of the initiatives to reverse the trend of progressive bio-diversity loss, the ‘agri-environment schemes’, aims to re-integrate nature conservation with farming.
Research: The research within the theme ‘Nature conservation in agricultural and urban landscapes’ focuses on the examination and evaluation of nature conservation efforts on farms and other multifunctional areas.
A range of species groups is included in the research (plants, birds, bees and hover flies). Previous research has demonstrated that agri-environment schemes on Dutch farms are not as effective as we hoped. Future research will have to demonstrate the most important factors that render the schemes ineffective. On one hand we intend to concentrate on specific species groups or even species (for instance, meadow birds or the black tailed godwit – Limosa limosa) to gain insight in what their ecological response is to the factors that are being modified to by the agri-environment schemes (e.g. nutrient supply, food supply, reproductive success). On the other hand, we plan to examine the role of environmental variables and how they may interfere with the effects of agri-environment schemes (e.g. landscape structure, groundwater table). Some of these questions will have to be addressed by research that will be executed in The Netherlands as well as neighbouring countries.
Additionally, we approach this theme from another angle by carrying out research in agricultural systems that are still very species rich. Investigating what the primary factors are that control species richness in these systems may help us understand why many nature conservation efforts in intensively used agricultural landscapes fail. This research will be carried out in the Swiss Pre-Alps where land-use is still extensive and extremely species-rich grasslands occur. Eventually, both approaches will have to lead to the protection of bio-diversity in agricultural landscapes.
Type of work: Development of an appropriate study design and sampling protocol, sampling of plants/birds/insects in the field; determination and sampling of the most important biotic and abiotic factors, compilation of data set, statistical analysis, reporting the results orally and verbally.