/* 
zero_srcsnk.c
fill the source and sink variables with 0.0 at the start of the simulation

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
Biome-BGC version 4.1.2
Copyright 2002, Peter E. Thornton
*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
*/

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <malloc.h>
#include "bgc_struct.h"     /* structure definitions */
#include "bgc_func.h"       /* function prototypes */
#include "bgc_constants.h"

/* zero the source and sink state variables */
int zero_srcsnk(cstate_struct* cs, nstate_struct* ns, wstate_struct* ws,
	summary_struct* summary)
{
	int ok=1;
	
	/* zero the water sources and sinks  */
	ws->prcp_src = 0.0;
	ws->outflow_snk = 0.0;
	ws->soilevap_snk = 0.0;
	ws->snowsubl_snk = 0.0;
	ws->canopyevap_snk = 0.0;
	ws->trans_snk = 0.0;

	/* zero the carbon sources and sinks */
	cs->psnsun_src = 0.0;
	cs->psnshade_src = 0.0;
	cs->leaf_mr_snk = 0.0;
	cs->leaf_gr_snk = 0.0;
	cs->froot_mr_snk = 0.0;
	cs->froot_gr_snk = 0.0;
	cs->livestem_mr_snk = 0.0;
	cs->livestem_gr_snk = 0.0;
	cs->deadstem_gr_snk = 0.0;
	cs->livecroot_mr_snk = 0.0;
	cs->livecroot_gr_snk = 0.0;
	cs->deadcroot_gr_snk = 0.0;
	cs->litr1_hr_snk = 0.0;
	cs->litr2_hr_snk = 0.0;
	cs->litr4_hr_snk = 0.0;
	cs->soil1_hr_snk = 0.0;
	cs->soil2_hr_snk = 0.0;
	cs->soil3_hr_snk = 0.0;
	cs->soil4_hr_snk = 0.0;
	cs->fire_snk = 0.0;
	
	/* zero the nitrogen sources and sinks */
	ns->nfix_src = 0.0;
	ns->ndep_src = 0.0;
	ns->nleached_snk = 0.0;
	ns->nvol_snk = 0.0;
	ns->fire_snk = 0.0;
	
	/* zero the summary variables */
	summary->cum_npp = 0.0;
	summary->cum_nep = 0.0;
	summary->cum_nee = 0.0;
	summary->cum_gpp = 0.0;
	summary->cum_mr = 0.0;
	summary->cum_gr = 0.0;
	summary->cum_hr = 0.0;
	summary->cum_fire = 0.0;
	
	return (!ok);
}