1. Oak Hill Case Soil Chemical Problems

2. SALT - RELATED PROBLEMS Ion Toxicities Ion Imbalances Soil Permeability Water Deficits

3. SALT - RELATED PROBLEMS Ion Toxicities Ion Imbalances Soil Permeability Water Deficits

4. Water deficits reflect salinity problems from salt concentrations Soil permeability reflects sodicity problems from sodium concentrations

5. Salinity A measure of the salt concentration of water

6. Common Salt Ions Ca 2+ K+K+ NO 3 - Mg 2+ HCO 3 - Na + SO 4 2- CO 3 2- Cl -

7. Salinity Measurement Measured as the electrical conductivity of water (EC w ) Expressed as decisiemens per meter (dS/m); formerly as mmhos/cm.

8.  sw vs EC e

9. Transpiration High salt concentration

10. Salt-Induced Water Deficits  WATER UPTAKE  cytokinin synthesis  leaf wilting  cell-turgor pressure  cell-turgor extensibility  DESICCATION  GROWTH  stomatal opening  photosynthesis  respiration  transpirational cooling

11. Sodium Hazard 0.25 0.75 2.25 1 2 3 4 Class Salinity Hazard EC(dS/m) at 25 o C C1-S4 C1-S3 C1-S2 C1-S1 C2-S4 C2-S3 C2-S2 C2-S1 C3-S4 C3-S3 C3-S2 C3-S1 C4-S4 C4-S3 C4-S2 C4-S1

12. Sodicity A measure of the sodium [Na + ] concentration in relation to the calcium [Ca +2 ] and magnesium [Mg +2 ] concentrations of water

13. Sodicity Measurement Measured as the sodium absorption ratio of water (SAR w ) Expressed as the ratio: Na + / ([Ca +2 + Mg +2 ]/2) 1/2 Where the concentration of each ion is expressed in milliequivalents per liter (meq/L)

14. Problem With a water-quality report providing sodium, calcium, and magnesium concentrations as 76, 146, and 39 mg/L, how do we express these in meq/L?

15. Atomic Weights

18. Sodium: 76 mg/L / 23 mg/meq = 3.3 meq/L Calcium: 146 mg/L / 20 mg/meq = 7.3 meq/L Magnesium: 39 mg/L / 12 mg/meq = 3.2 meq/L SAR W = 3.3/ ([7.3 +3.2]/2) 1/2 = 3.3/(5.25) 1/2 = 3.3/2.29 = 1.44

19. Sodium Hazard 0.25 0.75 2.25 1 2 3 4 Class Salinity Hazard EC(dS/m) at 25 o C C1-S4 C1-S3 C1-S2 C1-S1 C2-S4 C2-S3 C2-S2 C2-S1 C3-S4 C3-S3 C3-S2 C3-S1 C4-S4 C4-S3 C4-S2 C4-S1

20. Problem With a water-quality report providing a bicarbonate concentration of 366 mg/L, how do we express this in meq/L and what is its significance?

21. Residual Sodium Carbonate RSC = [CO 3 -2 ] + [HCO 3 - ] - [Ca +2 ] + [Mg +2 ] Where [ ] = ion concentrations in milliequivalents per liter (meq/L)

22. Atomic Weights

23. Residual Sodium Carbonate RSC = [0] + [6.0] - [7.3] - [3.2] = -4.5

24. RSC Hazard

25. Amendments Required to Neutralize Residual Carbonates RSC * 234 lbs gypsum/acre-foot RSC * 133 lbs sulfuric acid/acre-foot

26. soil aggregate

27. O O O O O O Na H H H H H H H H H H H H +

28. Na Effects on Soil Permeability  O 2 status   hardness water  infiltration  drainage  percolation  retention Soil Porosity  macroporosity  pore continuity aeration strength

29. Salt-Affected Soils

30. Soil Types

31. Soil Salinity Hazard

32. Soil Sodium Hazard

33. Turfgrass Salinity Tolerance