watercycle.h

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/********************************************************************************************
**    iLand - an individual based forest landscape and disturbance model
**    http://iland-model.org
**    Copyright (C) 2009-  Werner Rammer, Rupert Seidl
**
**    This program is free software: you can redistribute it and/or modify
**    it under the terms of the GNU General Public License as published by
**    the Free Software Foundation, either version 3 of the License, or
**    (at your option) any later version.
**
**    This program is distributed in the hope that it will be useful,
**    but WITHOUT ANY WARRANTY; without even the implied warranty of
**    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
**    GNU General Public License for more details.
**
**    You should have received a copy of the GNU General Public License
**    along with this program.  If not, see <http://www.gnu.org/licenses/>.
********************************************************************************************/
 
#ifndef WATERCYCLE_H
#define WATERCYCLE_H
#include <QHash>
 
class ResourceUnit;
struct ClimateDay;
class WaterCycle; // forward
class WaterOut; // forward
namespace Water
{
 
class Permafrost; // forward
 
class SnowPack
{
    friend class ::WaterCycle;
public:
    SnowPack(): mSnowPack(0.) {}
    void setSnow(double snow_mm) { mSnowPack = snow_mm; }
    double flow(const double &preciptitation_mm, const double &temperature);
    inline double add(const double &preciptitation_mm, const double &temperature);
    double snowPack() const { return mSnowPack; }
    double snowDepth() const {  return mSnowPack / mSnowDensity; /* mm = kg/m2, density=kg/m3, mm / density = m */ }
private:
    double mSnowPack; 
    // parameters of snow class
    static double mSnowTemperature; 
    static double mSnowDensity; 
 
};
 
class Canopy
{
 
public:
    // setup
    void setup(); 
    void setStandParameters(const double LAIneedle, const double LAIbroadleave, const double maxCanopyConductance);
    // actions
    double flow(const double &preciptitation_mm);
    double evapotranspirationBGC(const ClimateDay *climate, const double daylength_h); 
    double evapotranspiration3PG(const ClimateDay *climate, const double daylength_h, const double combined_response); 
    // properties
    double interception() const  { return mInterception; } 
    double evaporationCanopy() const { return mEvaporation; } 
    double avgMaxCanopyConductance() const { return mAvgMaxCanopyConductance; } 
    const double *referenceEvapotranspiration() const { return mET0; } 
 
private:
    double mLAINeedle; // leaf area index of coniferous species
    double mLAIBroadleaved; // leaf area index of broadlevaed species
    double mLAI; // total leaf area index
    double mAvgMaxCanopyConductance; // maximum weighted canopy conductance (m/s)
    double mInterception; 
    double mEvaporation; 
    // Penman-Monteith parameters
    double mAirDensity; // density of air [kg / m3]
    double mET0[12]; 
    // parameters for interception
    static double mNeedleFactor; 
    static double mDecidousFactor; 
    friend class ::WaterCycle;
    // GCC problems with friend class and namespaces: http://www.ogre3d.org/forums/viewtopic.php?f=10&t=47540
};
 
 
} // end namespace Water
 
 
class WaterCycle
{
public:
    WaterCycle();
    ~WaterCycle();
    void setup(const ResourceUnit *ru);
    void setContent(double content, double snow_mm) { mContent = content; mSnowPack.setSnow(snow_mm); }
    // actions
    void run(); 
    static void resetPsiMin(); 
    // properties
    double fieldCapacity() const { return mFieldCapacity; } 
    double waterHoldingCapacity() const { return mFieldCapacity - mPermanentWiltingPoint; }
    const double &psi_kPa(const int doy) const { return mPsi[doy]; } 
    double soilDepth() const { return mSoilDepth; } 
    double currentContent() const { return mContent; } 
    double currentSnowPack() const { return mSnowPack.snowPack(); } 
    double canopyConductance() const { return mCanopyConductance; } 
    double effectiveLAI() const { return mEffectiveLAI; } 
    double meanSoilWaterContent() const {return mMeanSoilWaterContent; } 
    double meanGrowingSeasonSWC() const { return mMeanGrowingSeasonSWC; } 
    const double *referenceEvapotranspiration() const { return mCanopy.referenceEvapotranspiration(); }
    double estPsiMin(int phenologyGroup) const;
    // elements
    const Water::Permafrost *permafrost() const { return mPermafrost; }
 
private:
    struct RUSpeciesShares {
        RUSpeciesShares(const int n_species):ground_vegetation_share(0.), adult_trees_share(0.) { lai_share.resize(n_species); }
        QVector<double> lai_share; // for each species a share [0..1]
        double ground_vegetation_share; // the share of ground vegetation; sum(lai_share)+ground_vegetation_share = 1
        double adult_trees_share; // share of adult trees (>4m) on total LAI (relevant for aging)
        double total_lai; // total effective LAI
    };
    void calculatePsiMin() const;
 
    int mLastYear; 
    inline double psiFromHeight(const double mm) const; // kPa for water height "mm"
    inline double heightFromPsi(const double psi_kpa) const; // water height (mm) at water potential psi (kilopascal)
    inline double calculateBaseSoilAtmosphereResponse(const double psi_kpa, const double vpd_kpa, const double psi_min, const double vpd_exp); 
    double mPsi_koeff_b; 
    double mPsi_sat; 
    double mTheta_sat; 
    const ResourceUnit *mRU; 
    Water::Canopy mCanopy; 
    Water::SnowPack mSnowPack; 
    Water::Permafrost *mPermafrost; 
    double mSoilDepth; 
    double mContent; 
    double mFieldCapacity; 
    double mPermanentWiltingPoint; 
    double mPsi[366]; 
    void getStandValues(RUSpeciesShares &species_shares); 
    inline double calculateSoilAtmosphereResponse(RUSpeciesShares &species_share, const double psi_kpa, const double vpd_kpa);
    double mLAINeedle;
    double mLAIBroadleaved;
    double mCanopyConductance; 
    double mEffectiveLAI; 
    // ground vegetation
    double mGroundVegetationLAI; 
    double mGroundVegetationPsiMin; 
    // annual sums
    double mTotalET; 
    double mTotalExcess; 
    double mSnowRad; 
    int mSnowDays; 
    double mMeanSoilWaterContent; 
    double mMeanGrowingSeasonSWC; 
 
    static QHash<int, double> mEstPsi;
 
    friend class ::WaterOut;
    friend class Water::Permafrost;
};
 
class WaterCycleData
{
public:
    double water_to_ground[366];
    double snow_cover[366];
};
 
#endif // WATERCYCLE_H