How is agriculture production affected？

[Tonyzhao610]

In terms of agricultural productivity growth, the documentation mentions changes in yield due to increased fertilizer usage or endogenous irrigation. However, the file FAO_ag_CROSIT.csv only contains two parameters, IRR_lo/hi and RFD_hi/lo, which represent the yield change rates for irrigated and rain-fed crops, respectively. So, how is the change in yield due to fertilizer application reflected?
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