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TRANSCRIPT
MANEJO DE SALINIDAD
EN LOS
CAMPOS DE GOLF
David M. Kopec Ph.D.
University of Arizona
SALINE or SALTY WATER
OBJECTIVES :
1. Where “do salts come from”
2. Why is salt a problem- plant perspective
3. Irrigation options and cultural management
4. Grass selection
SALTS
• Are natural in soils from soil particles.
• Are applied in turf fertilizer.
• Are (mostly) soluble, so they end up in turf
irrigation water.
Water
• Water
• HOH
• H+ -OH
H+ -OH
SALTS
• Potassium nitrate
(KN03)
• Ammonium nitrate
((NH4)2 N03)
• Dolomite
(MgSo4)
No3 - +H
-OH
Water = H+-OH
TURFGRASS LEAF – A SWAMP COOLER
SOIL SALINITY …. Makes it
harder for the plant to…..
1. TAKE UP WATER at the roots
2. MOVE WATER up to the leaves
3. HAVE ENOUGH WATER inside the
leaves for leaf cooling,
photosynthesis, and growth.
4. Plants look “drought stressed” (blue)
5. Plants are dwarfed and compact !
SALT PROBLEMS IN TURF ??
Droughty looking plants,
even when soil moisture
is high !
Fails the screw driver soil
moisture probe test !
TURFGRASS IS STUNTED !
SALT PROBLEMS IN TURF ??
White crusts on the
soil surface around
the edge of the turf
an in between plants.
Water Testing for Salinity
Total salinity
electro-conductuvity “EC” (dS/m or
mmhos/ cm)
total dissolved solids “TDS” (ppm or mg/l)
Total Salinity Guidelines for
Irrigation Water
Salinity Hazard EC (dS m-1) TDS (ppm)
Low <0.75 < 500
Medium 0.75 – 1.5 500 -1000
High 1.5 – 3.0 1000-2000
Very High > 3.0 > 2000
Field Salinity Meter
Develop a STRATEGY for
dealing with the salt problem
Eliminate the source of the salts R.O.
Soil treatment
Drainage
Cultivation
Water options
Leaching fraction
Blending water sources
Drainage
Encourages
leaching of salts
when extra water
is added.
Cultivation Practices
Core cultivation
Slicing
Spiking
Deep-tine cultivation
Water injection
Drilling
Solid-tine cultivation
Vibratory plows
Deep tine
Drill and fill
AERIFICATION and SOIL LAYERS
IRRIGATION & SALTS
• Irrigate more frequently
• Irrigate with more water
• DRAINAGE
• DRAINAGE
• DRAINAGE
• DRAINAGE
LEACHING
REQUIREMNT
• How much extra of the same salty
water you need to apply to keep the
soil salts (in the saturated paste
extract) from reaching the level
where growth will be less than 100%
of normal.
• Percent of applied water that needs
to pass below the root zone !
WASH AWAY SALTS IN THE
WATER THAT THE ROOTS ‘SEE’
• LEACHING !
• Watering with more of the same salty
water !
• Prevents excess salts from building
up !
• Water enough to keep the salt level
at some ‘tolerable’ level.
Leaching Requirement
Calculations
Leaching Requirement = 2 pieces of data
EC(water)
EC(turf species) turf tolerance in soil solution
Leaching Requirement =
EC(water) _
5EC (turf species) - EC(water)
Turf Species Salt Tolerance
Species Name Salinity Tolerance Threshold EC
Alkaligrass Tolerant 8.5
Saltgrass Tolerant 20.0 (or higher ?)
Bermudagrass Tolerant 10.0
Tall fescue Tolerant 6.5
Perennial ryegrass Tolerant 6.5
Seashore Paspalum Tolerant 20.0 (or higher ?)
Creeping red fescue Moderately tolerant 4.5
Creeping bentgrass Moderately tolerant 3.7
Kentucky bluegrass Moderately sensitive 3.0
Zoysiagrass Moderately sensitive 2.4
Annual bluegrass Very sensitive 1.5
IRRIGATION ADJUSTMENT based on
the L.F.
target irrigation (inches)
1 – (L.R. )
EXAMPLE : Test Results have L.F. of 20%
IRRIGATION ADJUSTMENT based on
the L- F
0.4 inch target
[ 1 – (.20) ]
0.4 “
[ 0.8 ]= 0.50” actual
• Higher salinity of water ……….
• Higher L.R. value becomes …….
• Higher applied water amount becomes………
IRRIGATION & SALTS
• Choose salt tolerant species
• Choose salt tolerant cultivars
• ……affects the “LF” equation
EC( irr water)
5EC (grass tolerance) - (EC irr water)X 100
MORE WAYS TO DEAL WITH
SALTY WATER
1. Leaching fraction
2. Enhanced drainage (aerification)
3. Use more salt tolerant turf
grasses
4. Blend water
Turf Species Salt Tolerance
Species Name Salinity Tolerance Threshold EC
Alkaligrass Tolerant 8.5
Saltgrass Tolerant 20.0 (or higher ?)
Bermudagrass Tolerant 10.0
Tall fescue Tolerant 6.5
Perennial ryegrass Tolerant 6.5
Seashore Paspalum Tolerant 20.0 (or higher ?)
Creeping red fescue Moderately tolerant 4.5
Creeping bentgrass Moderately tolerant 3.7
Kentucky bluegrass Moderately sensitive 3.0
Zoysiagrass Moderately sensitive 2.4
Annual bluegrass Very sensitive 1.5
SALINITY TOLERANCE BENTGRASS
MOST SALT TOLERANT:
Mariner, Seaside II, Grand Prix, Seaside,
MEDIUM :
18th Green, Century, Backspin, L-93
LOW:
SR 1119, Regent, Putter, Penncross, Penn G-6,
Providence.
Ryegrass salt tolerance.
• Covet
• Galileo
• Magellan
• Brightstar
SLT
• Karma
• Sideways
• Mitey
• AllStar
• Penguin
• Penguin II
• Thrive
• Bandelero
• Hancock
• Stamina
• Navajo
• Zoom
Alkaligrass cultivars
‘Fult’s’ alkaligrass
‘Salty ’ alkaligrass
Kentucky Bluegrass Cultivar Salinity Tolerance
Good Fair Poor
NorthStar Nuglade Kenblue
Moonlight Abbey Park
SR-2000 Blacksburg Huntsville
Limousine Award Livingston
Eclipse Midnight P105
Challenger
Seashore paspalum
MORE WAYS TO DEAL WITH
SALTY WATER
1. Leaching fraction
2. Enhanced drainage (aerification)
3. Use more salt tolerant turf grasses
4. Blend water
BLENDING
BLENDING WATER
Mix “good water” with “poor
water”
Salt level is equal to the
proportional amounts of
both water sources that
make up the new 100%
blended water
EXAMPLE
WATER “A” has EC of 1800
ppm TDS (bad)
WATER “B” has EC of 500
ppm TDS (good).
What is the EC of 75% “B”
and 25% “A” ??? = “C”
EXAMPLE : EC of blended water
25 % of blended water has EC of 1800 ppm “A”
75% of blended water has EC of 500 ppm “B”
( .25 X 1800) + (.75 X 500) =
(450) + (375) = 825 ppm “C”
Develop a STRATEGY for
dealing with the salt problem
Eliminate the source of the salts (R.O.)
Soil treatment
Drainage
Cultivation
Water management
Leaching fraction
Blending water sources
STOP
Turf-type Saltgrass (Distichlis)
SALTS GET CONFUSED WITH
Sodium levels in water !
GYPSUM requirement ! (gypsum does not get rid of salt in the root zone solution)
High bicarbonates in water !
The need for acid injection !
CONSIDERATIONS
For TEX DEC 2004
Still has to go to
DELL
TURFGRASS IS STUNTED !
SALINITY AND GROWTH
SOIL SALINITY …. Makes it
harder for the plant to…..
1. TAKE UP WATER at the roots
2. MOVE WATER up to the leaves
3. HAVE ENOUGH WATER inside the
leaves for leaf cooling,
photosynthesis, and growth.
Increased salinity hinders germination of KBG when
temperature are low.
Tall fescue is unaffected by temperature regardless of salt
level.
REM : 6 mmho / cm = 3840 ppm.
Salinity
affects young
turf plants of
KBG more so
than tall
fescue
Salt stress is worse as temperature is increased !
Plant shape and appearance of weeping alkaligrass
and weeping lovegrass.
Left - Puccinellia distans, or Weeping alkaligrass.
Right - Eragrostis curvula, Weeping lovegrass
HARAVANDI 1
Canada 2
Duncan roots
Root growth is maintained under salt stress more than shoot
growth
GRASS < 4 4 – 8 8 – 16 > 16
KBG
Creep
Red Fes
Tall Fes
Per Rye
Creep
bentgrass
Alkali
grass
Poa triv
Ann blue
West
wheat
APPROXIMATE SALINITY TOLERANCE OF
TURFGRASS GROWING IN SOIL SOLUTION
Electrical conductivity [Ec] in ds/m or mmhos/cm
GRASS < 4 4 – 8 8 – 16 > 16
Centipede Blue
gramma
Bermuda
Zoysia
St. Aug.
Seashore
paspalum
Distichlis
> 38
APPROXIMATE SALINITY TOLERANCE OF
TURFGRASS GROWING IN SOIL SOLUTION
Electrical conductivity [Ec] in ds/m or mmhos/cm
Cultivar Selection - Salt Tolerant
Grasses?
Not in high demand
Not in high supply
Turf quality issues
Seed costs
Halo-phytes may be slow to establish
Some are “roadside” while some are better in
quality
CREEPING BENTGRASS VARIETIES vs.
SALINITY TOLERANCE
Good salinity tolerance : Seaside II,
Mariner Grand Prix, Sea Side, 18th
Green.
Poor Salinity Tolerance : Providence,
Pro/Cup Penn G-6, Penncross,
Putter, Regent SR 1119.
PERENNIAL RYEGRASS
• ‘ BRIGHSTAR SLT ‘
• ‘ NAVAJO ‘
Turf-type Saltgrass (Distichlis)
AMOUNT OF WATER NEEDED TO LEACH IS
RELATED TO:
• What is the actual salt level of the irrigation water.
EC( irr water)
• What is the salt level in the drainage water , or
what is the salt level of the soil (soil EC = saturated
paste extract) that the grass will tolerate before any
growth is reduced.
EC (drain water)
LEACHING FRACTION:
EC( irr water)
EC (drain water)X 100
EC( irr water)
EC (drain water)X 100
1. The more salty the irrigation water is,
2. The less salty the salt tolerance of the turf is,
…… the higher the leaching fraction will be !
EXAMPLE : LF calculation
KENTUCKY BLUEGRASS
• EC (irr water) of irrigation water is 0.8 dS m-1
• EC (max. value for No Growth Reduction) is 4.0 dS m-1
0.8 dS m-1
4.0 dS m-1X 100 = 20%
SALT LEVELS IN IRRIGATION
WATER
Hazard Class EC (dSm-1) TDS (ppm)
low < 0.75 < 500
medium 0.75 -1.5 500 -1,000
high 1.5 - 3.0 1,000 - 2,000
very high > 3.0 > 2,000
Warm
Season< 4 4 – 8 8 – 16 > 16
Centipede Blue
gramma
Bermuda
Zoysia
St. Aug.
Seashore
paspalum
Distichlis
> 30
APPROXIMATE SALINITY TOLERANCE OF
TURFGRASS GROWING IN SOIL SOLUTION
Electrical conductivity [Ec] in ds/m or mmhos/cm
GRASS < 4 4 – 8 8 – 16 > 16
KBG
Creep
Red Fes
Tall Fes
Per Rye
Creep
bentgrass
Alkali
grass
Poa triv
Ann blue
Western
wheat
APPROXIMATE SALINITY TOLERANCE OF
TURFGRASS GROWING IN SOIL SOLUTION
Electrical conductivity [EC] in ds/m or mmhos/cm
Cool
Season< 4 4 – 8 8 – 16 > 16
KBG
Creep
Red Fes
Tall Fes
Per Rye
Creep
bentgrass
Alkali
grass
Poa triv
Ann blue
Western
wheat
APPROXIMATE SALINITY TOLERANCE OF
TURFGRASS GROWING IN SOIL SOLUTION
Electrical conductivity [EC] in ds/m or mmhos/cm
YOUR FRIEND
VACUOLE
Soft lined Water bag !
By pulling inside
minerals and other
charged molecules
inside the vacuole,
more water is attracted
to move inside the
vacuole.
Plant Soil Salinity Tolerance(saturated soil paste extract, ECe)
Soil Salinity Tolerance
ECe at 0% Yield
Reduction
(threshold ECe*)
ECe at 50% Yield
Reduction
Tolerated by very
sensitive plants<1.5 1.5-5
Moderately sensitive
plants must be used1.5-3 5-10
Moderately tolerant plants
must be used3-6 10-15
Tolerant plants must be
used6-10 15-21
Very tolerant plants must
be used>10 >21
*ECe above which a reduction in yield will occur
IRRIGATION & SALTS
HELP THE SOIL DRAIN !
Aerification
Tile drains
“Sandy” soils
SALTS DISSOLVE IN WATER.
• Change the chemical properties of
water (+) and (--) charges to compete
with water itself !
• Conduct an electrical charge (can be
measured)
SALTS
• Salts are the combination of any
negative ion (--) called an (anion)
………
• and any positive ion (+) called a
ca+ion.
SALTS ARE ACTUALLY DRY COMPOUNDS !
SALTS GET CONFUSED WITH
Sodium levels in water !
GYPSUM requirement ! (gypsum does not get rid of salt in the root zone solution)
High bicarbonates in water !
The need for acid injection !
Plant Soil Salinity Tolerance(saturated soil paste extract, ECe)
Soil Salinity Tolerance
ECe at 0% Yield
Reduction
(threshold ECe*)
ECe at 50% Yield
Reduction
Tolerated by very
sensitive plants<1.5 1.5-5
Moderately sensitive
plants must be used1.5-3 5-10
Moderately tolerant plants
must be used3-6 10-15
Tolerant plants must be
used6-10 15-21
Very tolerant plants must
be used>10 >21
*ECe above which a reduction in yield will occur
WATER QUALITY FOR TURF IRRIGATION
Only one “part” of a water quality test.
COMPONENTS:
1. SALIN ITY
2. Sodium hazard
3. Residual sodium carbonate
4. Specific ion toxicity
5. pH
Determining the SOURCE of the salts
Soil
Irrigation water
Water table
“Added salts”
1. Over fertilization
2. Deicing salts/road
spray
SOIL MOISTURE as affected
by salinity
ET Requires Water
Salinity decreases … the amount of
AVAILABLE soil water.
A.k.a.
- More salt in water….
water stress / wilting occurs at higher soil moisture contents.
decreases available water
that plant can take up
nnnuptakeWater
decreaseed
Transpiration
Turf wilts even
though soil is wet.
Slow water Movement
into roots
Increasing
salinit y 2
1
3
4
