AGCI research programme: Climate Science and Ecohydrology

AGCI postdoc: Marjan van de Weg

Improving a next generation DGVM by implementing dynamic plant traits


This postdoc project aims to utilize different types of datasets (plant traits, flux data, soil moisture maps) to improve the way leaf traits and soil-plant-atmosphere interactions are represented in a currently existing dynamic global vegetation model (DGVM). The global terrestrial carbon and water cycle are intrinsically coupled through numerous feedbacks between the biosphere and atmosphere. To simulate current and future global carbon and water fluxes, as well as their interactions with the terrestrial biosphere, the best available option is the use of a DGVM.  However, current DGVMs differ widely in their climate predictions and these diverging predictions limit the extent to which assessments of ecosystems services, good governance of water systems, and adaptation strategies can be implemented. Plant traits are known to determine biochemical capacity for carbon uptake of an ecosystem, and there is a growing international effort to develop a next generation DGVM in which the quantification of the dynamics and differences of vegetation characteristics (‘traits’) plays an important role. In recent years, an extensive amount of global plant trait data has become available for parameterization DGVMs. Furthermore, plot level tower observations of water and carbon fluxes (i.e. eddy covariance measurements) have increased, together with products from Earth Observing satellites such as global soil moisture maps.

Short CV

Marjan’s research so far has mostly focused on the controls of different processes that underpin the global carbon cycle (i.e. photosynthesis and respiration). Her first introduction in eco-physiological work was as a MSc student in the Systems Ecology group at the VU University Amsterdam, for which she measured ecosystem respiration in a long-term warming experiment in Abisko, Sweden. Since then, she has carried out eco-physiological fieldwork in a variety of other ecosystems, ranging from tropical forests to agricultural wetlands and the North Slope of Alaska.

For her PhD research, Marjan investigated how leaf traits, together with environmental parameters, control the CO2 uptake of a tropical montane cloud forest. The work included fieldwork in the Peruvian Andes, as well as the use of the ecosystem parameters derived from that fieldwork in a soil-plant-atmosphere model (the SPA model from Mat Williams) for scaling stand level carbon uptake.

Her postdoc at the Marine Biological Laboratory consisted of projects that investigate the effects of environmental change (e.g. increased nutrient availability, species shifts, increased fire) on the carbon and nitrogen cycle in the Alaskan tundra. This included working in the Arctic LTER (Long Term Ecological Research) sites at the Toolik Lake field station in Alaska, as well as work at a large tundra fire scar from 2007 on the North Slope.

Academic training

2010PhD, School of Geosciences, University of Edinburgh, UK
2006MSc, Global Environmental Change, University of Edinburgh, UK
2005MSc, Ecology, VU University Amsterdam
2003BSc, Biology, VU University Amsterdam

Professional employment history

2010-presentPostdoctoral researcher at the Marine Biological Laboratory, Woods Hole, MA.

Selected publication

Van de Weg, M.J., Meir, P., Grace, J., and Damian Ramos, G. (2011). Variation of photosynthetic capacity, leaf dark respiration and leaf traits in the canopy of a tropical montane cloud forest in Peru. Oecologia.

Van de Weg, M.J., Meir, P., Grace, J., and Atkin, O.K. (2009). Altitudinal variation in leaf mass per unit area, leaf tissue density and foliar nitrogen and phosphorus content along an Amazon-Andes gradient in Peru.Plant Ecology and Diversity, 2(3), 243-254.

Dorrepaal, E., Toet, S., Van Logtestijn, R.S.S., Swart, E., Van de Weg, M.J., Callaghan, T.V., Aerts, R. (2009). Carbon respiration from subsurface peat accelerated by climate warming in the sub-arctic. Nature, 460: 616-619.

Van de Weg, M.J., Reay, D.S., Gouriveau, F., Grace, J. (2008). Pollution-swapping: nitrate interception and nitrous oxide production in a constructed wetland in the Scottish Borders. In: Bosch, A., Teira, M.R., Villar, J.M. (eds.), Towards a better efficiency in N use. Editorial Milenio, Lleida (Spain).