Determination of crop dynamic and aerodynamic parameters for lodging prediction

Development and application of a model for calculating the risk of stem and root lodging in maize

“…Aerodynamic investigations of the maize shoot have shown that it behaves as a damped harmonic oscillator after being subjected to wind loading (Joseph et al, 2020). Therefore, the mechanistic process of lodging in maize can be modelled in the same way as other plant species with similar aerodynamic points of structural failure (e.g.…”

“…wheat). A generalised model used to describe the lodging process in cereals (Baker et al, 2014;Berry et al, 2003) can therefore be adapted for maize, taking account of maize-specific calibrations estimated by Joseph et al (2020). The maize lodging model assumes that the unit of lodging is a single plant and stem lodging is expected if the wind-induced bending moment (leverage of the shoot) exceeds the stem failure moment (stem strength at the point of failure), while root lodging is expected if the leverage force exceeds the anchorage failure moment (anchorage strength at the point of failure).…”

“…Therefore, failure moment of the anchorage system is assumed to be proportional to the product of the spread of the crown roots cubed and the shear strength of the surrounding soil, similar to anchorage models for wheat (Baker et al, 1998), sunflower (Sporoso et al 2008;2010) and oats (Mohammadi et al, 2020) The bending moment (B) at any point along the shoot is obtained as a function of mean wind speed 𝑈𝑈 � , using the density of air (ρ = 1.2 kg/m 3 ), the drag area of the shoot (ACF = 0.153 m 2 ), the shoot's height at centre of gravity (X), the shoot's natural frequency (fn), the acceleration due to gravity (g = 9.81 m s 2 ), the turbulence intensity (𝐼𝐼 𝑢𝑢 ) and the shoot's damping ratio (𝜃𝜃= 0.13). Values for ACF, X, 𝐼𝐼 𝑢𝑢 and fn were experimentally determined for maize by Joseph et al (2020).…”

“…This model assumes that the unit of lodging is a single plant and stem lodging is expected if the wind-induced bending moment (leverage) of the shoot exceeds the stem failure moment, and root lodging is expected if the leverage force of the plant exceeds the anchorage failure moment. Recently the aerodynamic properties of plants have been ascertained experimentally (Joseph et al, 2020) which enables the cereal lodging model to be developed to better account for interactions between the wind and the plant for a range of plant species including maize. However, to date there is no satisfactory description of the lodging process in maize that accounts for all the key processes: plant/wind interaction, stem strength and anchorage strength.…”

Experimental Evaluation of a 3D-Printed Fluidic System for a Directional Anemometer

“…Recently, the importance of detecting the magnitude and, possibly, the direction of air streams has emerged in several innovative fields. Precision agriculture [ 1 ] requires the monitoring of several parameters, among which the wind velocity is recognized to be an important factor [ 2 , 3 ]. Even the annual production of honey was found to be affected by the wind intensity [ 4 ].…”