Model parameters

Both 1D and 2D models share the same weather and soil parameters (Table 1 and 2). The 1D model uses the main and intercrop parameters as listed in Table 3 and 4, respectively. In contrast, the 2D model uses the main and intercrop parameters as listed in Table 5 and 6, respectively.

Table 1. Weather model parameters for both 1D and 2D models

Branch	Parameter	Brief description	Unit
Weather	Latitude	Latitude of field site	radians
	Longitude	Longitude of field site	radians
	Reference height	Height where meteorological data was measured	m
	Sky overcast type	UOC (value 0) or SOC (value 1) only	-
Date and time	Day of year	1 for Jan 1, 32 for Feb 1, etc.	-
	Hour	e.g., 12.00 for 12:00 hours, 12.50 for 12:30 hours, etc.	-
	Day	Day in month	-
	Month	1 for Jan, 2 for Feb, etc.	-
	Year	In four digits, e.g., 1999, 2000, etc.	-
Whole day weather¹	Max. temperature	Maximum air temperature	° C
	Min. temperature	Minimum air temperature	° C
	Total radiation		MJ m^-2 day^-1
	Vapour pressure		mbar
	Wind speed		km day^-1
Daily weather file	File name	File pathname for daily weather data	-
	No. of lines between each day	see here.	-
Hourly weather²	Temperature	Air temperature	° C
	Radiation		W m^-2
	Vapour pressure		mbar
	Wind speed		m s^-1
Hourly weather file	File name	File pathname for hourly weather data	-
	No. of lines between each day	see here.	-

¹ Parameters Max. temperature, Min. temperature, Total radiation, Vapour pressure and Wind speed will be ignored if daily weather file is specified. To use these parameters rather than from the weather file, delete the Daily weather file branch.

² Parameters Temperature, Radiation, Vapour pressure and Wind speed will be ignored if hourly weather file is specified. To use these parameters rather than from the weather file, delete the Hourly weather file branch.

Table 2. Soil model parameters for both 1D and 2D models

Branch	Parameter	Brief description	Unit
Soil	Depth of soil studied	Depth where soil properties were measured	m
	Water amount		m³ m^-3
	Bulk density		Mg m^-3
	Organic matter		m³ m^-3
	Particle-size distribution	Must be in this order: clay, silt then sand	%
	Suction-water relationship	Soil moisture characteristic curve between soil suction and soil water amount. Suction range must include at least from soil saturation to field capacity.	Suction (m); Soil water amount (m³ m^-3)

Table 3. Main model parameters for 1D model

Branch	Parameter	Brief description	Unit
Main	Mean leaf drag	Mean drag of all leaves	-
	Eddy diffusivity coefficient	Eddy diffusivity decay constant	-

Table 4. Intercrop model parameters for 1D model

Branch	Parameter	Brief description	Unit
Intercrop		This branch will list all crops in the system
Crop	Name	Crop name (one word only), e.g., "maize" and "sunflower"	-
	Height	Plant height	m
	Planting density	Number of plants per unit ground area (m²)	-
Canopy		This branch will list all the layers (groups of leaves) in the canopy
	Stomatal resistance	Empirical coefficients a₁ and a₂ for stomatal resistance	-
	Scatter coefficient	Coefficient of radiation scatter	-
	Canopy width	Mean width of canopy	m
	Canopy cover	Fractional canopy cover (in fraction)	-
Layer	Depth from canopy top	see Fig. 5	m
	LAI	Leaf area index	m² m^-2
	Mean leaf width	Mean width of all leaves	m
	Leaf inclination density	Distribution of leaf inclination density	-
	Leaf azimuth density	Distribution of leaf azimuth density	-

Table 5. Main model parameters for 2D model

Branch	Parameter	Brief description	Unit
Main	Mean leaf drag	Mean drag of all leaves	-
	Eddy diffusivity coefficient	Eddy diffusivity decay constant	-
	No. beams per cell	Number of solar beams to "push" into each cell	-
	No. of inclination intervals	Number of inclination intervals to divide the whole sky	-
	No. of azimuth intervals	Number of azimuth intervals to divide the whole sky	-

Table 6. Intercrop model parameters for 2D model

Branch	Parameter	Brief description	Unit
Intercrop		This branch will list all crops in the system
	Azimuth of planting row	Planting row direction	radians
	Cell width	Width of one cell in the grid network, E_x	m
	Cell height	Height of one cell in the grid network, E_z	m
Crop	Name	Crop name (one word only), e.g., "maize" and "sunflower"	-
	Height	Plant height	m
	Planting density	Number of plants per unit ground area (m²)	-
	Planting distance	Distance from reference point	m
Canopy		This branch will list all individual leaves in the canopy
	Stomatal resistance	Empirical coefficients a₁ and a₂ for stomatal resistance	-
	Scatter coefficient	Coefficient of radiation scatter	-
	Type of leaf arch	Values 0 and 1 are for linear and polynomial leaf arch, respectively	-
Leaf	Inclination	Leaf inclination	radians
	Azimuth	Leaf azimuth	radians
	Arch coefficients	Leaf arch	m
	Curvature coefficients	Leaf shape curvature	m

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