managing water quality in growing media

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Managing Water Managing Water Quality Quality in Growing Media in Growing Media David Wm. Reed David Wm. Reed Department of Horticultural Department of Horticultural Sciences Sciences Texas A&M University Texas A&M University

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Managing Water Quality in Growing Media. David Wm. Reed Department of Horticultural Sciences Texas A&M University. Factors That Impact Water Quality in Growing Media. Factors That Impact Water Quality in Growing Media. Factors That Impact Water Quality in Growing Media. - PowerPoint PPT Presentation

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Page 1: Managing Water Quality  in Growing Media

Managing Water Quality Managing Water Quality in Growing Mediain Growing Media

Managing Water Quality Managing Water Quality in Growing Mediain Growing Media

David Wm. ReedDavid Wm. ReedDepartment of Horticultural SciencesDepartment of Horticultural Sciences

Texas A&M UniversityTexas A&M University

Page 2: Managing Water Quality  in Growing Media

Factors That Impact Water Quality in Growing MediaFactors That Impact Water Quality in Growing Media

Page 3: Managing Water Quality  in Growing Media

Factors That Impact Water Quality in Growing MediaFactors That Impact Water Quality in Growing Media

Page 4: Managing Water Quality  in Growing Media

Factors That Impact Water Quality in Growing MediaFactors That Impact Water Quality in Growing Media

Page 5: Managing Water Quality  in Growing Media

Factors That Impact Water Quality in Growing MediaFactors That Impact Water Quality in Growing Media

Page 6: Managing Water Quality  in Growing Media

Factors That Impact Water Quality in Growing MediaFactors That Impact Water Quality in Growing Media

Page 7: Managing Water Quality  in Growing Media

Factors That Impact Water Quality in Growing MediaFactors That Impact Water Quality in Growing Media

Page 8: Managing Water Quality  in Growing Media

Factors That Impact Water Quality in Growing MediaFactors That Impact Water Quality in Growing Media

Page 9: Managing Water Quality  in Growing Media

Factors That Impact Water Quality in Growing MediaFactors That Impact Water Quality in Growing Media

Page 10: Managing Water Quality  in Growing Media

Factors That Impact Water Quality in GrowingFactors That Impact Water Quality in Growing Media Media

Page 11: Managing Water Quality  in Growing Media

Factors That Impact Water Quality in Growing MediaFactors That Impact Water Quality in Growing Media

Page 12: Managing Water Quality  in Growing Media

Factors That Impact Water Factors That Impact Water Quality in Growing MediaQuality in Growing Media

Factors That Impact Water Factors That Impact Water Quality in Growing MediaQuality in Growing Media

Irrigation Water QualityIrrigation Water Quality

Page 13: Managing Water Quality  in Growing Media

Factors That Impact Water Quality in Growing MediaFactors That Impact Water Quality in Growing Media

Page 14: Managing Water Quality  in Growing Media

Irrigation Water QualityIrrigation Water QualityIrrigation Water QualityIrrigation Water Quality Chemical PropertiesChemical Properties

pHpH alkalinityalkalinity ECEC SARSAR

Individual Soluble SaltsIndividual Soluble Salts Water Treatment MethodsWater Treatment Methods

Page 15: Managing Water Quality  in Growing Media

Growing Medium EC and pHGrowing Medium EC and pH

(from Lang 1996)(from Lang 1996)

SaturatedSaturated

PastePaste

1:21:2

DilutionDilution

PourPour

ThroughThrough

pHpH

All PlantsAll Plants 5.5-6.55.5-6.5 5.5-6.55.5-6.5 5.5-6.55.5-6.5

EC dS/mEC dS/m

Young PlantsYoung Plants 1-21-2 0.5-0.90.5-0.9

Established Established PlantsPlants

2-32-3 0.8-1.20.8-1.2 3-53-5

Page 16: Managing Water Quality  in Growing Media

Irrigation Water Alkalinity LimitsIrrigation Water Alkalinity Limits Irrigation Water Alkalinity LimitsIrrigation Water Alkalinity Limits

Minimum MaximumMinimum Maximumppmppm meq/l meq/l ppmppm meq/lmeq/l

Plugs and/or seedlingsPlugs and/or seedlings 3838 0.750.75 6666 1.31.3

Small pots/shallow flatsSmall pots/shallow flats 3838 0.750.75 8686 1.71.7

4" to 5" pots/deep flats4" to 5" pots/deep flats 3838 0.750.75 106106 2.12.1

6” pots/long term crops6” pots/long term crops 6363 1.251.25 131131 2.62.6

(from Bailey 1996)(from Bailey 1996)

Page 17: Managing Water Quality  in Growing Media

Irrigation Water Critical LimitsIrrigation Water Critical Limits

(from Biernbaum 1994)(from Biernbaum 1994)

MinimumMinimum MaximumMaximum

pHpH 5.55.5 7.07.0

EC (dS/m)EC (dS/m) 0.20.2 0.80.8

ppmppm

AlkalinityAlkalinity 4040 160160

CaCa 2525 7575

MgMg 1010 3030

SS 00 4040

NaNa 00 2020

ClCl 00 2020

FeFe 00 11

ZnZn 00 0.50.5

BB 00 0.10.1

CuCu 00 0.10.1

MoMo 00 0.10.1

FF 00 0.10.1

Page 18: Managing Water Quality  in Growing Media

Plant Nutrient Requirements Supplied Plant Nutrient Requirements Supplied by Irrigation Waterby Irrigation Water

NutrientNutrient

Minimum ppmMinimum ppm

To Supply PlantTo Supply Plant

RequirementsRequirements

SS 20-30 ppm20-30 ppm

CaCa 40 ppm40 ppm

MgMg 20 ppm20 ppm

BB 0.3 ppm0.3 ppm

Page 19: Managing Water Quality  in Growing Media

Sulfur Supplied by Irrigation WaterSulfur Supplied by Irrigation Water

(from Reddy 1996)(from Reddy 1996)20-30 ppm supplies most plant’s requirement20-30 ppm supplies most plant’s requirement

Page 20: Managing Water Quality  in Growing Media

Irrigation Water QualityIrrigation Water QualityIrrigation Water QualityIrrigation Water Quality

Water Treatment MethodsWater Treatment Methods

Page 21: Managing Water Quality  in Growing Media

Water Purification MethodsWater Purification Methods

(from Reed 1996)(from Reed 1996)

ReverseReverse

OsmosisOsmosis

WaterWater

SoftenerSoftener

AcidAcid

InjectionInjection

Aeration/Aeration/

OxidationOxidation

ActivatedActivated

Carbon/AlCarbon/Al

AlkalinityAlkalinity

(carbonates)(carbonates)XX XX

Total SaltsTotal Salts XX

SodiumSodium XX XX

ChlorideChloride XX XX

IronIron XX XX XX

BoronBoron XX

FluorideFluoride XX XX

ManganeseManganese XX XX XX

CopperCopper XX XX

CalciumCalcium XX XX

SulfateSulfate XX

Page 22: Managing Water Quality  in Growing Media

Reverse Osmosis UnitReverse Osmosis UnitReverse Osmosis UnitReverse Osmosis Unit

Page 23: Managing Water Quality  in Growing Media

Reverse Osmosis Water Purification To Decrease Salts

Reverse Osmosis Water Purification To Decrease Salts

Pretreatments:Pretreatments:

1) Polymer injection1) Polymer injection to coagulate due to high SDIto coagulate due to high SDI

2) Depth Filter2) Depth Filter to remove coagulated particlesto remove coagulated particles

3) Charcoal Filter3) Charcoal Filter to remove municipal chlorineto remove municipal chlorine

4) Ion Exchange4) Ion Exchange to remove residual polymerto remove residual polymer

Purification System:Purification System:

Reverse OsmosisReverse Osmosis using polyamide membranesusing polyamide membranes

(pH resistant, chlorine sensitive)(pH resistant, chlorine sensitive)

Production CapacityProduction Capacity

Purified Water Purified Water 5,760 gallons per day5,760 gallons per day

Blended Water (40/60)Blended Water (40/60) 14,400 gallons per day 14,400 gallons per day

Blend to EC ofBlend to EC of 0.75 dS/m (approx. 500 ppm)0.75 dS/m (approx. 500 ppm) (from Reed 1996)(from Reed 1996)

Page 24: Managing Water Quality  in Growing Media

Reverse Osmosis Water Purification To Decrease Salts

Reverse Osmosis Water Purification To Decrease Salts

CostsCosts

Lease and ServiceLease and Service $900 per month$900 per month

Water (1.09/1,000)Water (1.09/1,000) $700 per month$700 per month

ElectricityElectricity $200 per month$200 per month

TotalTotal $1800 per month$1800 per month

Purified Water CostPurified Water Cost 1 cent per gallon1 cent per gallon

Blended Water CostsBlended Water Costs 0.4 cents per gallon0.4 cents per gallon

Production Space IrrigatedProduction Space Irrigated

80,000 to 135,000 square foot of 6-inch production space80,000 to 135,000 square foot of 6-inch production space

(at 12-20 oz/6”pot/day at 0.9 sq. ft. space/6”pot)(at 12-20 oz/6”pot/day at 0.9 sq. ft. space/6”pot)

Purified Water Used ForPurified Water Used For

Salt sensitive foliage plants and mist propagationSalt sensitive foliage plants and mist propagation (from Reed 1996)(from Reed 1996)

Page 25: Managing Water Quality  in Growing Media

Acid InjectionAcid Injection80% Neutralization to Approx. pH 5.880% Neutralization to Approx. pH 5.8

Acid InjectionAcid Injection80% Neutralization to Approx. pH 5.880% Neutralization to Approx. pH 5.8

Fluid ounce of acid Fluid ounce of acid ppm ppm

per 1,000 of water,per 1,000 of water, per oz. perper oz. per

for each meqfor each meq 1,000 gal1,000 gal

AcidAcid of alkalinityof alkalinity waterwaterNitric (67%)Nitric (67%) 6.786.78 1.64 N1.64 N

Phosphoric (75%)Phosphoric (75%) 8.308.30 2.88 P2.88 P

Sulfuric (35%)Sulfuric (35%) 11.0011.00 1.14 S1.14 S

(from Bailey 1996)(from Bailey 1996)

Page 26: Managing Water Quality  in Growing Media

Fertilizer ProgramFertilizer ProgramFertilizer ProgramFertilizer Program Soluble Liquid FeedSoluble Liquid Feed Granular IncorporationGranular Incorporation Controlled Release IncorporationControlled Release Incorporation

Page 27: Managing Water Quality  in Growing Media

Factors That Impact Water Quality in Growing MediaFactors That Impact Water Quality in Growing Media

Page 28: Managing Water Quality  in Growing Media

EC of Soluble Fertilizers & Water QualityEC of Soluble Fertilizers & Water Quality

(from Peterson 1996)(from Peterson 1996)

Page 29: Managing Water Quality  in Growing Media

Fertility & Salt Stratification in the Root ZoneFertility & Salt Stratification in the Root ZoneSubirrigation – New Guinea Impatiens ‘Barbados’Subirrigation – New Guinea Impatiens ‘Barbados’

(from Kent & Reed 1996)(from Kent & Reed 1996)

Page 30: Managing Water Quality  in Growing Media

Irrigation MethodIrrigation MethodIrrigation MethodIrrigation Method Top-Watering vs. SubirrigationTop-Watering vs. Subirrigation Vertical Stratification of SaltsVertical Stratification of Salts Evaporation from SurfaceEvaporation from Surface Leaching FractionLeaching Fraction

Page 31: Managing Water Quality  in Growing Media

Factors That Impact Water Quality in Growing MediaFactors That Impact Water Quality in Growing Media

Page 32: Managing Water Quality  in Growing Media

Vertical Stratification of Soluble SaltsVertical Stratification of Soluble Salts

Page 33: Managing Water Quality  in Growing Media

Salt Stratification in the Root Zone with Different Salt Stratification in the Root Zone with Different Irrigation MethodsIrrigation Methods

(from Molitor, 1990, Warncke & Krauskopf 1983)(from Molitor, 1990, Warncke & Krauskopf 1983)

Page 34: Managing Water Quality  in Growing Media

Evaporation from SurfaceEvaporation from Surface

Causes Vertical Stratification of SaltsCauses Vertical Stratification of Salts

Page 35: Managing Water Quality  in Growing Media

(from Argo and Biernbaum 1995(from Argo and Biernbaum 1995Warncke & Krauskopf 1983)Warncke & Krauskopf 1983)

Effect of Evaporation on Salt StratificationEffect of Evaporation on Salt StratificationPoinsettia ‘Gutbier V-14 Glory’Poinsettia ‘Gutbier V-14 Glory’

Page 36: Managing Water Quality  in Growing Media

Effect of Evaporation on Salt StratificationEffect of Evaporation on Salt StratificationPoinsettia ‘Gutbier V-14 Glory’Poinsettia ‘Gutbier V-14 Glory’

(from Argo and Biernbaum 1995(from Argo and Biernbaum 1995Warncke & Krauskopf 1983)Warncke & Krauskopf 1983)

Page 37: Managing Water Quality  in Growing Media

Vertical Stratification of Soluble SaltsVertical Stratification of Soluble Salts

andand

Root DistributionRoot Distribution

Page 38: Managing Water Quality  in Growing Media

Salt Stratification & Root DistributionSalt Stratification & Root Distribution

Spathiphyllum in subirrigationSpathiphyllum in subirrigation

(from Kent & Reed, unpubl; (from Kent & Reed, unpubl; Warncke & Krauskopf 1983)Warncke & Krauskopf 1983)

Page 39: Managing Water Quality  in Growing Media

Track EC to MonitorTrack EC to Monitor Soluble Salt AccumulationSoluble Salt Accumulation Over FertilizationOver Fertilization Minimum Fertility LevelMinimum Fertility Level

Caution:Caution: DO NOT sample the top layer DO NOT sample the top layer

Page 40: Managing Water Quality  in Growing Media

Graphical Tracking: ECGraphical Tracking: EC

Crop: ______________________

Page 41: Managing Water Quality  in Growing Media

Leaching FractionLeaching Fraction

andand

Soluble Salt AccumulationSoluble Salt Accumulation

Page 42: Managing Water Quality  in Growing Media

Leaching in Top-Watering Vs. SubirrigationLeaching in Top-Watering Vs. Subirrigation

Page 43: Managing Water Quality  in Growing Media

Leaching Fraction in Top-WateringLeaching Fraction in Top-Watering

LF ~ 0.3-0.4LF ~ 0.3-0.4Low LFLow LF High LFHigh LF

LF LF EC ECww / (5(EC / (5(ECee(desired)(desired)-EC-ECww))))

Page 44: Managing Water Quality  in Growing Media

Effect of Leaching Fraction on Medium ECEffect of Leaching Fraction on Medium EC

Poinsettia ‘V-14 Glory’Poinsettia ‘V-14 Glory’

(from Yelanich and Biernbaum 1993,(from Yelanich and Biernbaum 1993,Warncke & Krauskopf 1983)Warncke & Krauskopf 1983)

0

1

2

3

4

5

6

ECdS/msat.ext.

2 4 6 8 10 12 14 16

Week

0.55 LF0.55 LF

0.35 LF0.35 LF

0.15 LF0.15 LF

0 LF0 LF

Page 45: Managing Water Quality  in Growing Media

Top Layer Salts and Wilting Upon IrrigationTop Layer Salts and Wilting Upon IrrigationEspecially Critical in SubirrigationEspecially Critical in Subirrigation

(from Todd & Reed 1998)(from Todd & Reed 1998)

Page 46: Managing Water Quality  in Growing Media

Leaching & Salt Removal From MediaLeaching & Salt Removal From MediaNew Guinea Impatiens ‘Blazon’ in SubirrigationNew Guinea Impatiens ‘Blazon’ in Subirrigation

(from Todd & Reed 1998)(from Todd & Reed 1998)

1 2 3 4 5 6 0 2 4 6 8 10 14 180

5

10

15

20

ECdS/m

Times LeachedmM CaCl2 + NaCl

Page 47: Managing Water Quality  in Growing Media

Determination of Determination of Soluble Salt Toxicity LimitsSoluble Salt Toxicity Limits

““Shoot Gun” ApproachShoot Gun” Approach

Page 48: Managing Water Quality  in Growing Media

Plant Response to 24 Texas Water SourcesPlant Response to 24 Texas Water Sources

(from Kent & Reed unpubl)(from Kent & Reed unpubl)

1.11.1

1.01.0

1.21.2

0.40.40.20.20.50.5

0.10.10.50.50.80.8

0.10.1

0.90.9 0.30.3

0.80.8

0.70.70.30.3

0.20.20.50.5

Page 49: Managing Water Quality  in Growing Media

Growth Versus EC with 24 Water SourcesGrowth Versus EC with 24 Water SourcesVinca ‘Apricot Delight’ Grown in SubirrigationVinca ‘Apricot Delight’ Grown in Subirrigation

(from Kent & Reed unpubl)(from Kent & Reed unpubl)

Page 50: Managing Water Quality  in Growing Media

Growth Versus EC with 24 Water SourcesGrowth Versus EC with 24 Water SourcesVinca ‘Apricot Delight’ Grown in SubirrigationVinca ‘Apricot Delight’ Grown in Subirrigation

(from Kent & Reed unpubl)(from Kent & Reed unpubl)

Page 51: Managing Water Quality  in Growing Media

Growth Versus EC with 24 Water SourcesGrowth Versus EC with 24 Water SourcesVinca ‘Apricot Delight’ Grown in SubirrigationVinca ‘Apricot Delight’ Grown in Subirrigation

(from Kent & Reed unpubl)(from Kent & Reed unpubl)

Page 52: Managing Water Quality  in Growing Media

(from Kent & Reed unpubl)(from Kent & Reed unpubl)

Growth Versus Na + Cl with 24 Water SourcesGrowth Versus Na + Cl with 24 Water SourcesVinca ‘Apricot Delight’ Grown in SubirrigationVinca ‘Apricot Delight’ Grown in Subirrigation

Page 53: Managing Water Quality  in Growing Media

Determination of Determination of Soluble Salt Toxicity LimitsSoluble Salt Toxicity Limits

Studies on Individual SaltsStudies on Individual Salts(cation + anion combinations)(cation + anion combinations)

Page 54: Managing Water Quality  in Growing Media

Chrysanthemum

Rose 0 mM 2.5 mM

0 mM

5 mM

7.5 mM 10 mM

2.5 mM 5 mM

7.5 mM 10 mM

Toxicity Limits to Sodium BicarbonateToxicity Limits to Sodium Bicarbonate

(from Valdez, PhD)(from Valdez, PhD)

Page 55: Managing Water Quality  in Growing Media

RoseRose MumMum VincaVincaHibiscus Hibiscus ‘Mango ‘Mango Breeze’Breeze’

Hibiscus Hibiscus

‘‘Bimini Bimini Breeze’Breeze’

SPAD SPAD Index Index

decreasedecreasePredicted mPredicted mMM NaHCONaHCO33

10%10% 0.80.8 3.23.2 6.06.0 2.12.1 4.24.2

20%20% 1.71.7 4.84.8 7.47.4 4.24.2 8.58.5

30%30% 2.82.8 6.16.1 8.48.4 6.36.3 12.712.7

40%40% 4.24.2 7.27.2 9.39.3 8.48.4 16.816.8

Predicted NaHCOPredicted NaHCO33 Toxicity Limit as a Toxicity Limit as aFunction of Chlorosis Function of Chlorosis

(from Valdez, PhD)(from Valdez, PhD)

Page 56: Managing Water Quality  in Growing Media

Determination of Determination of Soluble Salt Toxicity LimitsSoluble Salt Toxicity Limits

Studies on Individual SaltsStudies on Individual Salts(cation + anion combinations)(cation + anion combinations)

Problem With This ApproachProblem With This ApproachDo not know if the effect is due to the Do not know if the effect is due to the

cation or the anioncation or the anion

Page 57: Managing Water Quality  in Growing Media

Determination of Determination of Soluble Salt Toxicity LimitsSoluble Salt Toxicity Limits

Separation of Anion and Cation Separation of Anion and Cation Effects Using Mixture ExperimentsEffects Using Mixture Experiments

Page 58: Managing Water Quality  in Growing Media

½:0:½

Y0:1:0

X1:0:0

Z0:0:1

½:½:0

0:½:½

2/3:1/6:1/6

1/6:2/3:1/6 1/6:1/6:2/3

1/3:1/3:1/3

Pure blends

Tertiary blends

Centroid

Binary blends

Mixture ExperimentMixture ExperimentDesignDesign

Page 59: Managing Water Quality  in Growing Media

Rb+7.5mM

K+ 0 mM

Na+7.5mM Na+ 0 mM

2.5

3.5

4.5

5.5

Rb+ 0 mM

K+ 7.5mM

Mixture-Amount Experiments to Separate the

Na+ and HCO3- Effect in Sodium

Bicarbonate

Mixture-Amount Experiments to Separate the

Na+ and HCO3- Effect in Sodium

BicarbonateNa+ tox./K+ def.=-19%

HCO3- effect=-15%

Sh

oot

Dry

M

ass (

g)

(from Valdez, PhD)(from Valdez, PhD)

0 mM HCO30 mM HCO3

7.5 mM HCO37.5 mM HCO3

Page 60: Managing Water Quality  in Growing Media

0.00 1.00

0.25 0.75

0.50 0.50

0.75 0.25

1.00 0.00

1.00

2.00

3.00

4.00

5.00

6.00

2.5 HCO3-

2.5 mM total binary 2.5 mM total binary mixturemixture

0 HCO3-

Proportion of K+ and Na+

Na+=-19%

HCO3-=-19%

Sh

oot

Dry

M

ass (

g)

Na+

K+

Binary Mixture Experiments to Separate the

Na+ and HCO3- Effect in Sodium

Bicarbonate

Binary Mixture Experiments to Separate the

Na+ and HCO3- Effect in Sodium

Bicarbonate

(from Valdez, PhD)(from Valdez, PhD)

Page 61: Managing Water Quality  in Growing Media

Mixture-Amount Experiments To Separate Mixture-Amount Experiments To Separate Chloride, Bicarbonate and Sulfate EffectsChloride, Bicarbonate and Sulfate Effects

(from Kent & Reed unpubl)(from Kent & Reed unpubl)

Page 62: Managing Water Quality  in Growing Media

Separation of Chloride, Bicarbonate and Sulfate Effects Separation of Chloride, Bicarbonate and Sulfate Effects with Mixture-Amount Experimentswith Mixture-Amount Experiments

30 meq/l30 meq/l 45 meq/l45 meq/l 60 meq/l60 meq/l

Vinca ‘Pacifica Red’ in SubirrigationVinca ‘Pacifica Red’ in Subirrigation

HCOHCO33 HCO3HCO3HCO3HCO3

ClCl ClCl ClClSOSO44 SOSO44

SOSO44

Cation = NaCation = Na Cation = NaCation = Na Cation = NaCation = Na

(from Kent & Reed unpubl)(from Kent & Reed unpubl)

Page 63: Managing Water Quality  in Growing Media

Mixture-Amount Experiments To Separate Mixture-Amount Experiments To Separate Chloride, Bicarbonate and Sulfate EffectsChloride, Bicarbonate and Sulfate Effects

30 meq/l30 meq/l(1,700 to 2,500 ppm)(1,700 to 2,500 ppm)

45 meq/l45 meq/l(2,300 to 3,400 ppm)(2,300 to 3,400 ppm)

60 meq/l60 meq/l(2,800 to 4,400 ppm)(2,800 to 4,400 ppm)

Vinca ‘Pacifica Red’ in SubirrigationVinca ‘Pacifica Red’ in Subirrigation

HCOHCO33 HCO3HCO3HCO3HCO3

ClCl ClCl ClClSOSO44 SOSO44

SOSO44

Cation = NaCation = Na Cation = NaCation = Na Cation = NaCation = Na

(from Kent & Reed unpubl)(from Kent & Reed unpubl)

Page 64: Managing Water Quality  in Growing Media

ThanksThanksThanksThanks

Page 65: Managing Water Quality  in Growing Media

0

1

2

3

4

0 100 200 300 400

Soluble Fertilizer ppm N

EC

dS/

m20-20-2015-10-30

EC of Soluble Fertilizers & Water QualityEC of Soluble Fertilizers & Water Quality

Page 66: Managing Water Quality  in Growing Media

Rb+7.5mM

K+ 0 mM

Na+7.5mM Na+ 0 mM

2.5

3.5

4.5

5.5

Rb+ 0 mM

K+ 7.5mM

HCO3- effect=-15%

Na+ tox./K+ def.=-19%

Separation of Sodium and Bicarbonate Effect Separation of Sodium and Bicarbonate Effect Using Mixture ExperimentsUsing Mixture Experiments

(from Valdez, (from Valdez, Ph.D. dissertation)Ph.D. dissertation)

ggshootshootmassmass

Page 67: Managing Water Quality  in Growing Media

Leaching & Salt Removal From MediaLeaching & Salt Removal From MediaNew Guinea Impatiens ‘Illusion’ in SubirrigationNew Guinea Impatiens ‘Illusion’ in Subirrigation

(from Todd & Reed 1998)(from Todd & Reed 1998)

1 2 3 4 5 6 0 2 4 6 8 10 14 180

5

10

15

20

EC dS/m

Times Leached mM CaCl2 + NaCl