How dynamic is light inside canopies? Intercepting light in the real world
The conversion of light into biomass and harvestable product is one of the key processes that drive yield. Not only the amount of light intercepted by a crop canopy, but also the distribution of light is of great importance to maximize this so-called light use efficiency. Leaves within a canopy are exposed to a constantly changing light intensity, not only by the incoming sunlight, but also the movement of leaves in the upper part of the canopy.
Even though this phenomenon is well known, it has not been well characterized. In theory, an optimal distribution of light within a canopy should increase the light use efficiency. However, these estimates have been made using a static light environment. So, it is the question to what extent the variability of light inside a canopy is of influence to the light use efficiency.
We have developed a methodology to quantify the light environment in a crop canopy and its variability over time. For this, a new open-source, low cost, rugged light sensor (ceptometer) is used to measure light inside a canopy (DOI: 10.3791/59447). The low construction cost of this ceptometer allows measurement with a number of these rugged ceptometers at multiple levels inside a canopy, where the dynamic light environment can be measured and logged under real-world conditions in the field. A field experiment is planned in Cambridge (UK), in collaboration with Dr Johannes Kromdijk (Cambridge University).
With these data, the light environment and its variation inside a canopy can be analysed. Further, this light environment can be modelled using Functional Structural Plant modelling and studied to find ways for optimization of light distribution inside a canopy.
This project will involve hands-on (construction), field work and theoretical work (variation analysis and FSP modelling):
- Building and testing PARbars and waterproof Cave Pearl dataloggers
- Measuring light intensity at a range of levels in a crop canopy in the field (Cambridge, UK)
- Analysing collected data for variability and FSPmodelling
- This project, or parts of this project, can be done as a BSc thesis, MSc thesis or an internship
- Aspects of this project (e.g. field work, data analysis or FSP modelling) can be done as separate thesis projects