biomass.c 579 B

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  1. #include<stdio.h>
  2. #include<math.h>
  3. #include<stdlib.h>
  4. double biomass(double fpar, double solar_day, double evap_fr,
  5. double light_use_ef)
  6. {
  7. double result, apar, conversion_coefs;
  8. /*fPAR in Bastiaassen and Ali = a (= 1.257) * NDVI + b (= -0.161); */
  9. /*light use efficiency is variable for each crop! */
  10. /* Cotton light_use_ef in Uzbekistan is 1.9 */
  11. /* apar = (b+a*ndvi); */
  12. conversion_coefs = 0.0864 * 10;
  13. apar = fpar * (0.48 * solar_day);
  14. result = apar * light_use_ef * evap_fr * conversion_coefs;
  15. return result;
  16. }