public static void Decompose(ActiveSite site)
{
//---------------------------------------------------------------------
// Surface SOM1 decomposes to SOM2 with CO2 lost to respiration.
double som1c_surface = SiteVars.SOM1surface[site].Carbon;
if (som1c_surface > 0.0000001)
{
// Determine C/N ratios for flows to som2
double radds1 = OtherData.SurfaceActivePoolCNIntercept
+ OtherData.SurfaceActivePoolCNSlope * ((som1c_surface / SiteVars.SOM1surface[site].Nitrogen)
- OtherData.MinCNSurfMicrobes);
double ratioCNtoSOM2 = (som1c_surface / SiteVars.SOM1surface[site].Nitrogen) + radds1;
ratioCNtoSOM2 = System.Math.Max(ratioCNtoSOM2, OtherData.SurfaceActivePoolCNMinimum);
//Compute total C flow out of surface microbes.
double totalCflow = som1c_surface
* SiteVars.DecayFactor[site]
* PlugIn.DecayRateSurf //ClimateRegionData.DecayRateSurf[ecoregion]
* OtherData.MonthAdjust
* OtherData.LitterParameters[(int)LayerType.Surface].DecayRateMicrobes;
// If decomposition can occur, schedule flows associated with respiration
// and decomposition
if (SiteVars.SOM1surface[site].DecomposePossible(ratioCNtoSOM2, SiteVars.MineralN[site]))
{
//CO2 loss - Compute and schedule respiration flows.
double co2loss = totalCflow * OtherData.P1CO2_Surface;
double netCFlow = totalCflow - co2loss;
SiteVars.SOM1surface[site].Respiration(co2loss, site);
// Decompose Surface SOM1 to SOM2
SiteVars.SOM1surface[site].TransferCarbon(SiteVars.SOM2[site], netCFlow);
SiteVars.SOM1surface[site].TransferNitrogen(SiteVars.SOM2[site], netCFlow, som1c_surface, ratioCNtoSOM2, site);
}
}
//---------------------------------------------------------------------
// Soil SOM1 decomposes to SOM2 and SOM3 with CO2 loss and leaching
double som1c_soil = SiteVars.SOM1soil[site].Carbon;
if (som1c_soil > 0.0000001)
{
//Determine C/N ratios for flows to som2
double ratioCNtoSOM2 = Layer.BelowgroundDecompositionRatio(site,
OtherData.MinCNenterSOM2,
OtherData.MaxCNenterSOM2,
OtherData.MinContentN_SOM2);
//Compute total C flow out of soil microbes.
//Added impact of soil anaerobic conditions -rm 12/91
double textureEffect = OtherData.TextureEffectIntercept
+ OtherData.TextureEffectSlope * SiteVars.SoilPercentSand[site];
double anerb = SiteVars.AnaerobicEffect[site];
double totalCflow = som1c_soil
* SiteVars.DecayFactor[site]
* OtherData.LitterParameters[(int)LayerType.Soil].DecayRateMicrobes
* PlugIn.DecayRateSOM1
* textureEffect
* anerb
* OtherData.MonthAdjust;
// If soil SOM1 can decompose to SOM2, it will also go to SOM3.
// If it can't go to SOM2, it can't decompose at all.
// First determine if decomposition can occur:
if (SiteVars.SOM1soil[site].DecomposePossible(ratioCNtoSOM2, SiteVars.MineralN[site]))
{
//CO2 Loss - Compute and schedule respiration flows
double P1CO2_Soil = OtherData.P1CO2_Soil_Intercept + OtherData.P1CO2_Soil_Slope * SiteVars.SoilPercentSand[site];
double co2loss = totalCflow * P1CO2_Soil;
double netCFlow = totalCflow - co2loss;
SiteVars.SOM1soil[site].Respiration(co2loss, site);
// Decompose Soil SOM1 to SOM3
// The fraction of totalCflow that goes to SOM3 is a function of clay content.
double clayEffect = OtherData.PS1S3_Intercept + (OtherData.PS1S3_Slope * SiteVars.SoilPercentClay[site]);
double cFlowS1S3 = netCFlow * clayEffect * (1.0 + OtherData.AnaerobicImpactSlope * (1.0 - anerb));
//Compute and schedule C & N flows and update mineralization accumulators
double ratioCNto3 = Layer.BelowgroundDecompositionRatio(site,
OtherData.MinCNenterSOM3,
OtherData.MaxCNenterSOM3,
OtherData.MinContentN_SOM3);
//Partition and schedule C and N flows
SiteVars.SOM1soil[site].TransferCarbon(SiteVars.SOM3[site], cFlowS1S3);
SiteVars.SOM1soil[site].TransferNitrogen(SiteVars.SOM3[site], cFlowS1S3, som1c_soil, ratioCNto3, site);
// Leaching of Organics
// This only occurs when the water flow out of water layer 2
// exceeds a critical value. Use the same C/N ratios as for the flow to SOM3.
double cLeached = 0.0; // Carbon leached to a stream
if (SiteVars.WaterMovement[site] > 0.0) //Volume of water moving-ML. Used to be an index of water movement that indicates saturation (amov)
{
//ML deleted the linten function which was poorly described in the Century manual.
double leachTextureEffect = OtherData.OMLeachIntercept + OtherData.OMLeachSlope * SiteVars.SoilPercentSand[site];
double indexWaterMovement = SiteVars.WaterMovement[site] / (SiteVars.SoilDepth[site] * SiteVars.SoilFieldCapacity[site]);
cLeached = netCFlow * leachTextureEffect * indexWaterMovement;
//Partition and schedule C flows
SiteVars.SOM1soil[site].TransferCarbon(SiteVars.Stream[site], cLeached);
// Compute and schedule N flows and update mineralization accumulators
// Need to use the ratio for som1 for organic leaching
double ratioCN_SOM1soil = som1c_soil / SiteVars.SOM1soil[site].Nitrogen;
double orgflow = cLeached / ratioCN_SOM1soil;
SiteVars.SOM1soil[site].Nitrogen -= orgflow;
SiteVars.Stream[site].Nitrogen += orgflow;
SiteVars.MonthlyStreamN[site][Century.Month] += orgflow;
}
// C & N movement from SOM1 to SOM2.
// SOM2 gets what's left of totalCflow.
double cFlowS1S2 = netCFlow - cFlowS1S3 - cLeached;
//Partition and schedule C and N flows
SiteVars.SOM1soil[site].TransferCarbon(SiteVars.SOM2[site], cFlowS1S2);
SiteVars.SOM1soil[site].TransferNitrogen(SiteVars.SOM2[site], cFlowS1S2, som1c_soil, ratioCNtoSOM2, site);
}
}
//---------------------------------------------------------------------
//**********SOM2 decomposes to soil SOM1 and SOM3 with CO2 loss**********
double som2c = SiteVars.SOM2[site].Carbon;
if (som2c > 0.0000001)
{
// Determine C/N ratios for flows to SOM1
double ratioCNto1 = Layer.BelowgroundDecompositionRatio(site,
OtherData.MinCNenterSOM1,
OtherData.MaxCNenterSOM1,
OtherData.MinContentN_SOM1);
double anerb = SiteVars.AnaerobicEffect[site];
// Compute total C flow out of SOM2C
double totalCflow = som2c
* SiteVars.DecayFactor[site]
* PlugIn.DecayRateSOM2
* anerb //impact of soil anaerobic conditions
* OtherData.MonthAdjust;
// If SOM2 can decompose to SOM1, it will also go to SOM3.
// If it can't go to SOM1, it can't decompose at all.
if (SiteVars.SOM2[site].DecomposePossible(ratioCNto1, SiteVars.MineralN[site]))
{
//CO2 loss - Compute and schedule respiration flows
double co2loss = totalCflow * OtherData.FractionSOM2toCO2;
double netCFlow = totalCflow - co2loss;
SiteVars.SOM2[site].Respiration(co2loss, site);
// -----------------------------------------------
// Decompose SOM2 to SOM3, SOM3 gets what's left of totalCflow.
double clayEffect = OtherData.PS2S3_Intercept + OtherData.PS2S3_Slope * SiteVars.SoilPercentClay[site];
double cFlowS2S3 = netCFlow * clayEffect * (1.0 + OtherData.AnaerobicImpactSlope * (1.0 - anerb));
//Compute and schedule C and N flows and update mineralization accumulators
double ratioCNto3 = Layer.BelowgroundDecompositionRatio(site,
OtherData.MinCNenterSOM3,
OtherData.MaxCNenterSOM3,
OtherData.MinContentN_SOM3);
//Partition and schedule C and N flows
SiteVars.SOM2[site].TransferCarbon(SiteVars.SOM3[site], cFlowS2S3);
SiteVars.SOM2[site].TransferNitrogen(SiteVars.SOM3[site], cFlowS2S3, som2c, ratioCNto3, site);
// -----------------------------------------------
// Decompose SOM2 to SOM1
double cFlowS2S1 = netCFlow - cFlowS2S3;
// Compute and schedule N and C flows and update mineralization accumulators
ratioCNto1 = Layer.BelowgroundDecompositionRatio(site,
OtherData.MinCNenterSOM1,
OtherData.MaxCNenterSOM1,
OtherData.MinContentN_SOM1);
//Partition and schedule C and N flows
SiteVars.SOM2[site].TransferCarbon(SiteVars.SOM1soil[site], cFlowS2S1);
SiteVars.SOM2[site].TransferNitrogen(SiteVars.SOM1soil[site], cFlowS2S1, som2c, ratioCNto1, site);
}
}
//---------------------------------------------------------------------
// SOM3 decomposes to soil SOM1 with CO2 loss
double som3c = SiteVars.SOM3[site].Carbon;
if (som3c > 0.0000001)
{
//Determine C/N ratios for flows to SOM1.
double ratioCNto1 = Layer.BelowgroundDecompositionRatio(site,
OtherData.MinCNenterSOM1,
OtherData.MaxCNenterSOM1,
OtherData.MinContentN_SOM1);
double anerb = SiteVars.AnaerobicEffect[site];
//Compute total C flow out of SOM3C
double totalCflow = som3c
* SiteVars.DecayFactor[site]
* PlugIn.DecayRateSOM3
* anerb
* OtherData.MonthAdjust;
//If decomposition can occur,
if (SiteVars.SOM3[site].DecomposePossible(ratioCNto1, SiteVars.MineralN[site]))
{
// CO2 loss - Compute and schedule respiration flows.
double co2loss = totalCflow * OtherData.FractionSOM3toCO2 * anerb;
double netCFlow = totalCflow - co2loss;
SiteVars.SOM3[site].Respiration(co2loss, site);
// Decompose SOM3 to soil SOM1
double cFlowS3S1 = netCFlow;
// Partition and schedule C and N flows
SiteVars.SOM3[site].TransferCarbon(SiteVars.SOM1soil[site], cFlowS3S1);
SiteVars.SOM3[site].TransferNitrogen(SiteVars.SOM1soil[site], cFlowS3S1, som3c, ratioCNto1, site);
}
}
}
