A generic individual-based model to simulate morphogenesis, C-N acquisition and population dynamics in contrasting forage legumes
Authored by Gaetan Louarn, Lucas Faverjon
Date Published: 2018
DOI: 10.1093/aob/mcx154
Sponsors:
French National Institute for Agricultural Research (INRA)
Platforms:
Python
OpenAlea
Model Documentation:
Other Narrative
Model Code URLs:
Model code not found
Abstract
Background and Aims Individual-based models (IBMs) are promising tools
to disentangle plant interactions in multi-species grasslands and foster
innovative species mixtures. This study describes an IBM dealing with
the morphogenesis, growth and C-N acquisition of forage legumes that
integrates plastic responses from functional-structural plant models.
Methods A generic model was developed to account for herbaceous legume
species with contrasting above-and below-ground morphogenetic syndromes
and to integrate the responses of plants to light, water and N. Through
coupling with a radiative transfer model and a three-dimensional virtual
soil, the model allows dynamic resolution of competition for multiple
resources at individual plant level within a plant community. The
behaviour of the model was assessed on a range of monospecific stands
grown along gradients of light, water and N availability.
Key Results The model proved able to capture the diversity of
morphologies encountered among the forage legumes. The main
density-dependent features known about even-age plant populations were
correctly anticipated. The model predicted (1) the `reciprocal yield'
law relating average plant mass to density, (2) a self-thinning pattern
close to that measured for herbaceous species and (3) consistent changes
in the size structure of plant populations with time and pedo-climatic
conditions. In addition, plastic changes in the partitioning of dry
matter, the N acquisition mode and in the architecture of shoots and
roots emerged from the integration of plant responses to their local
environment. This resulted in taller plants and thinner roots when
competition was dominated by light, and shorter plants with relatively
more developed root systems when competition was dominated by soil
resources.
Conclusions A population dynamic model considering growth and
morphogenesis responses to multiple resources heterogeneously
distributed in the environment was presented. It should allow scaling
plant-plant interactions from individual to community levels without the
inconvenience of average plant models.
Tags
Competition
Individual-based model
phenotypic plasticity
architecture
Density
Grasslands
Plasticity
Plant-populations
Leaf-area
White clover
Biomass allocation
Legume
Population
dynamics
Nitrogen fixation
Medicago-sativa l
Root-system architecture
Dry-matter production
Trifolium-repens l
Nitrogen-fixation
Plant
development
Root development