Plant Ecology Modelling
The QUINCY model
QUINCY (Quantifying the effects of interacting nutrient cycles on terrestrial biosphere dynamics and their climate feedbacks) is a newly developed land surface model with fully coupled carbon, nitrogen, phosphorus and water cycles. QUINCY is built in a modular fashion, and is the ideal tool to test out new hypotheses and model processes. We of course have some new scientific features as well, such as the ability to track carbon and nitrogen isotopes, a short and long-term plant storage pool and decoupling photosynthesis from growth.
You can find the model description paper here and you can request access to the model code here.
Optimality principles
Often the inclusion of additional processes in models is synonymous with the addition of a large number of difficult to constrain parameters, so that the apparent improvement in model performance is cancelled by the increased uncertainty 31. Optimality theory offers an elegant mathematical solution to this problem. The theory states that plants aim to maximise their growth, survival and offspring fitness by adjusting their physiology and structure in response to biotic and abiotic factors in their environment. We have worked on a variety of optimality models, including optimal leaf nitrogen content under elevated CO2 in this paper and a generic model for leaf phenology in this paper.
Using manipulative experiments with process-based models
Manipulative ecosystem experiments are broadly defined as outdoor experimental setups in which one or multiple driving factors, or a combination of factors, are controlled to study their effects on ecosystem level processes. Such experiments are often highly instrumented and can provide data on a variety of ecosystem processes at high temporal resolution in a relatively controlled environment. As such, they are an ideal tool for improving process representation in mechanistic models. This is a common thread through our past and current work and you can read more on how we can best use experiments with models here.
