getsoilprop.c File Reference

#include <stdio.h>
#include <stdlib.h>

Include dependency graph for getsoilprop.c:

Go to the source code of this file.

Macros
#define	NCLASS   14
#define	COARSE   1 /* texture type for sandy soil */
#define	MEDIUM   2 /* texture type for medium (loamy) soil */
#define	FINE   3 /* texture type for fine soil */
#define	VERYFINE   4 /* texture type for volcanic soil */

Functions
void	getsoilprop (double *asand, double *asilt, double *aclay, double *bulkden, double *fieldcap, int *texture, int *soilclassification)

Macro Definition Documentation

#define COARSE   1 /* texture type for sandy soil */

#define FINE   3 /* texture type for fine soil */

#define MEDIUM   2 /* texture type for medium (loamy) soil */

#define NCLASS   14

#define VERYFINE   4 /* texture type for volcanic soil */

Function Documentation

void getsoilprop	(	double *	asand,
		double *	asilt,
		double *	aclay,
		double *	bulkden,
		double *	fieldcap,
		int *	texture,
		int *	soilclassification
	)

    {
      static double satcond[NCLASS] = {0.0, 0.000176, 0.0001563,
                                      0.00003467, 0.0000072, 0.00000695,
                                      0.0000063, 0.0000017, 0.00000245,
                                      0.000002167, 0.000001033,
                                      0.000001283, 0.0000080, 0.0000080};
      static double bulk_density[NCLASS] = {0.0, 1.55, 1.50, 1.43, 1.36,
                                           1.39, 1.35, 1.24, 1.30, 1.28,
                                           1.19, 1.15, 1.40, 0.75};
      static double field_capacity[NCLASS] = {0.0, 0.14, 0.18, 0.22, 0.32,
                                             0.29, 0.28, 0.40, 0.36,
                                             0.36, 0.46, 0.45, 0.33,
                                             0.70};
      int   soil_indx;
      double ksat;
      double sand, silt, clay;

      sand = *asand * 100;
      silt = *asilt * 100;
      clay = *aclay * 100;

      if ((sand > 100 || sand < 0) || (silt > 100 || silt < 0) ||
          (clay > 100 || clay < 0)) {
        fprintf(stderr, "Invalid texture in getsoilprop: sand = %f,", sand);
        fprintf(stderr, " silt = %f, clay = %f\n", silt, clay);
        exit(1);
      }

      if (*texture == VERYFINE) {
        /* volcanic */
        soil_indx = 13;
      } else if ((sand >= 85) && ((-2.0/3.0)*silt - clay + 10 >= 0)) {
        /* sand */
        soil_indx = 1;
      } else if (((-2.0/3.0)*silt - clay + 10 <= 0) &&
                 (-0.5*silt - clay + 15 >= 0)) {
        /* loamy sand */
        soil_indx = 2;
      } else if (((-0.5*silt-clay+15 <= 0) && (clay <= 20) && (sand >= 52)) ||
                 ((sand <= 52) && (silt <= 50) && (clay <= 7))) {
        /* sandy loam */
        soil_indx = 3;
      } else if ((sand <= 50) && (silt >= 50) && (clay <= 27)) {
        if ((sand <= 20) && (clay <= 10)) {
          /* silt */
          soil_indx = 12;
        } else {
          /* silt loam */
          soil_indx = 4;
        }
      } else if ((sand >= 23 && sand <= 52) && (silt >= 28 && silt <= 50) &&
                 (clay >= 7 && clay <= 27)) {
        /* loam */
        soil_indx = 5;
      } else if ((sand >= 45 && sand <= 80) && (silt <= 28) &&
                 (clay >= 20 && clay <= 35)) {
        /* sandy clay loam */
        soil_indx = 6;
      } else if ((sand <= 20) && (clay >= 27 && clay <= 40)) {
        /* silty clay loam */
        soil_indx = 7;
      } else if ((sand >= 20 && sand <= 45) && (clay >= 27 && clay <= 40)) {
        /* clay loam */
        soil_indx = 8;
      } else if ((sand >= 45 && sand <= 65) && (silt <= 20) &&
                 (clay >= 35 && clay <= 55)) {
        /* sandy clay */
        soil_indx = 9;
      } else if ((sand <= 20) && (silt >= 40 && silt <= 60) &&
                 (clay >= 40 && clay <= 60)) {
        /* silty clay */
        soil_indx = 10;
      } else if ((sand <= 45) && (silt <= 40) && (clay >= 40)) {
        /* clay */
        soil_indx = 11;
      } else {
        fprintf(stderr, "Unknown texture type: sand = %f, silt = %f,", sand,
                silt);
        fprintf(stderr, " clay = %f\n", clay);
        exit(1);
      }

      *bulkden = bulk_density[soil_indx];
      *fieldcap = field_capacity[soil_indx];
      ksat = satcond[soil_indx]*100.0;    /* Convert m/sec to cm/sec */
      *soilclassification=soil_indx-1;

/*      printf("Soil classification = %1d\n", soil_indx);
      printf("standard_bulkden = %10.6lf\n", *bulkden);
      printf("standard_fieldcap = %10.6lf\n", *fieldcap);
      printf("standard_ksat = %10.6lf\n", ksat); */

      return;
    }