Files related to the paper 'Nitrogen fixation mechanisms and distribution patterns of UCYN-A in the global ocean'
The folder 'UCYN-A_GitHub' contains different files.
(1) Matlab codes to generate Fig. 3a and Fig. 4a. The provided code will help to generate the variations in N2 fixation rate of UCYN-A at different light intensities and temperatures.
(2) '.xlsx' files for the new experimental data used in Fig. 3 and Fig. 4.
The generation of Fig. 3a requires three scripts in the 'UCYN-A_GitHub' folder, the 'UCYNA_Vary_Light.m', the 'UCYNA_Vary_Light_Size.m', and the 'Plot_Nfix.m'.
(1) First we need to run 'UCYNA_Vary_Light.m' to get the N2 fixation rate at different light intensities. This will also generate a light vs N2 fixation rate plot. It will take approximately 20 seconds to run. However, an increase in the step length of L_range from 0:1:800 to 0:20:800 will substantially reduce the runtime.
(2) To obtain the range of variations in N2 fixation rate at different light intensities, run 'UCYNA_Vary_Light_Size.m'. Make sure to keep the same step length of L_range as in (1).
(3) Then run 'Plot_Nfix.m' to generate the plot.
We also need 'viscocity_temperature_Jumars_1993.csv' file to run (1) and (2).
To generate Fig. 4a, run 'UCYNA_Vary_Temperature.m' to calculate N2 fixation rates across different temperatures. This will create the temperature vs. N2 fixation rate plot in about five seconds. Reducing the step size in T_range from -5:5:35 to -5:0.1:35 will significantly increase the runtime but will more accurately capture the shape shown in Fig. 4a.
Please note that the script outputs actual N2 fixation rates, whereas Fig. 4a presents normalized rates for easier comparison with the data, and the code provided does not include the shaded region displayed in Fig. 4a.
To download Matlab, you will need to create a MathWorks account. Follow these steps:
(1) Open a MathWorks account at https://www.mathworks.com/login/. (2) Once logged in, select "Get MATLAB" and then click on the "Start a Free Trial" button. (3) You will be prompted to download Matlab, which is available for Windows, Linux, and Mac computers. (4) Follow the on-screen instructions to install Matlab. The installation process may take up to 30 minutes. (5) The free trial provides unlimited access for 30 days.
The codes were tested using Matlab R2022b.