X axis shows the independent and Y axis shows the dependent.
Explanation:
As the independent variable is always plotted on the X-axis of the graph the Y-axis shows the dependent variable that is affected by the X variables Time is an independent variable and is always shown along the X-axis.
Such as the image showed tells about the data of N2O biofuel emissions from 2009-10. Thus this will be plotted along the X-axis and Y-axis will show the amount of nitrogen fertilizer applied.