Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.
-
Upload
merry-anthony -
Category
Documents
-
view
223 -
download
0
Transcript of Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.
![Page 1: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/1.jpg)
Thomas ObrezaSoil and Water Science Dept.
Univ. of Florida
Soil Fertility and pH
![Page 2: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/2.jpg)
Soil fertility: How soils hold nutrientsOrganic matterCation exchange capacitySorption (Sorb = To take up and hold).
Soil pH, liming, and acidification
![Page 3: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/3.jpg)
Soil fertility
Ridge
Flatwoods
![Page 4: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/4.jpg)
1. The ability of a soil to store nutrients in a form easily available to plants.
2. The degree to which nutrient leaching is prevented by a soil.
![Page 5: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/5.jpg)
1. Contained in organic matter (humus).Nitrogen, phosphorus, sulfur, etc.
2. Nutrient Soil electrostatic attraction, a.k.a. “Cation Exchange Capacity” (CEC).
Cations like H+, Ca2+, Mg2+, and K+.
3. Sorption by certain soil components.Phosphorus.
Movement of a non-retained nutrient like nitrate-N (NO3
-)is driven by water.
![Page 6: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/6.jpg)
Property Influence or Effect
Texture CEC; Sorption
Organic matter Nutrient storehouse; CEC
pH CEC; Sorption
Sand grain coatings Sorption
Water-holding cap. Movement of soluble nutrients
![Page 7: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/7.jpg)
Organic Matter
Nutrient retention mechanism #1
![Page 8: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/8.jpg)
Element Percentage
Carbon 50
Nitrogen 5
Phosphorus 0.5
Sulfur 0.5
Other nutrients Trace amounts
![Page 9: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/9.jpg)
For every 1% organic matter in the top 6 inches of soil, N mineralization =About 20 lbs N per acre per year.About ½ lb N per 1000 square ft per
year.
![Page 10: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/10.jpg)
Cation Exchange Capacity
Nutrient retention mechanism #2
![Page 11: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/11.jpg)
Clay or humus particle
Ca
Ca
Ca
KK K Mg
HH
H
H
_
_
_
__
_ __
__
__
_
Apply ammonium nitrate fertilizer: NH4+, NO3
-
CationExchangeCapacity
_
Clay or humus particle
__
_
__
_ __
_
__
__
+ 2H+, K+, NO3-
HH
NH4
KK
NH4
NH4 Ca
Ca
CaMg
![Page 12: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/12.jpg)
Cation exchange capacity:clay vs. organic matter
![Page 13: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/13.jpg)
MaterialApproximate CEC
(meq/100 g)
Quartz 1 – 2
Al and Fe hydrous oxides ≈ 4
Kaolinite clay 1 – 10
Illite clay 10 – 30
Montmorillionite clay 80 – 150
Vermiculite clay 100 – 200+
Organic matter 150 – 500
![Page 14: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/14.jpg)
Soil seriesCEC
meq/100 g% due to
clay% due to
OM
Candler(Central FL Ridge)
3.5 14% 86%
Immokalee(Gulf flatwoods)
4.8 6% 94%
Riviera(Indian River flatwoods)
4.8 19% 81%
![Page 15: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/15.jpg)
Sorption
Nutrient retention mechanism #3
![Page 16: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/16.jpg)
Nearlyinsoluble
Fe-P, Al-P
Nearlyinsoluble
Ca-P
Solublephosphate
H2PO4-
At low pH
Fe, Al
At high pH
Ca
pH 6.5Best P availability
Sorptionexample
![Page 17: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/17.jpg)
Is there a limit to the amount of P asoil can hold?
Yes.
What determines P-holding capacity?
Fe, Al, Ca
Why is sorption important?
Keeps P from leaching.
Can a sandy Florida soil hold P?
Depends on what’s in it.
![Page 18: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/18.jpg)
Coated sand Non-coated sand
![Page 19: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/19.jpg)
Tavares sand Immokalee sand
![Page 20: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/20.jpg)
NutrientIonic form in soil
solutionPrecipitation or sorption?
Mobile in sandy soil?
N NH4+, NO3
- No Yes
P PO43- Yes Yes/No*
K K+ No Yes
Ca, Mg Ca2+, Mg2+ Yes No
S SO4- Yes Yes/No*
Cu, Mn, Fe, Zn
Cu2+, Mn2+, Fe3+, Zn2+ Yes No
B, Mo, Cl H3BO3, MoO42-, Cl-
Mo – Yes
B, Cl – No
B, Cl – Yes
Mo – No
*Depends on soil properties
![Page 21: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/21.jpg)
Soil pH, liming, and acidification
![Page 22: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/22.jpg)
Measure of soil acidity or alkalinity.Importance:
Nutrient availability.Soil microbial activity.
![Page 23: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/23.jpg)
0 7 14
ACIDIC BASICNeutral
1 2 3 4 5 6 9 10 11 12 138
A decrease of 1 pH unit equals a10X increase in acidity.
![Page 24: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/24.jpg)
0
100
4.0 5.0 6.0 7.0 8.0
Plantbenefit
Plantinjury
Toxicity DeficiencyRel
ativ
e pl
ant
yiel
d (%
)
![Page 25: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/25.jpg)
Soil pHandnutrientavailability
![Page 26: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/26.jpg)
Portable pH meter
![Page 27: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/27.jpg)
Causes:Over-liming.Calcareous fill material.Alkaline irrigation water.
Symptoms:Micronutrient deficiencies.
![Page 28: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/28.jpg)
Over-liming
![Page 29: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/29.jpg)
Calcareous soil
![Page 30: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/30.jpg)
High pH construction residue
![Page 31: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/31.jpg)
Calcareous fill material
![Page 32: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/32.jpg)
Alkaline irrigation water
![Page 33: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/33.jpg)
High pH effects
![Page 34: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/34.jpg)
Magnesiumdeficiency
![Page 35: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/35.jpg)
Iron deficiency
![Page 36: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/36.jpg)
Iron deficiency
![Page 37: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/37.jpg)
Measuring soil pH
![Page 38: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/38.jpg)
1:2 soil/water mixture.
Wait 30 minutes.Check pH meter
calibration.Measure pH of
liquid above soil.
![Page 39: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/39.jpg)
![Page 40: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/40.jpg)
Supplies calciumNeutralizes acidityRaises soil pHUsually means calcium carbonate
![Page 41: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/41.jpg)
![Page 42: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/42.jpg)
![Page 43: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/43.jpg)
Acidification
![Page 44: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/44.jpg)
Can’t do much with soils filled with lime rock or shell.If you have to landscape these soils,
choose plants that grow well at high pH.
Marginally-alkaline soils can be acidified with elemental sulfur.
![Page 45: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/45.jpg)
![Page 46: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/46.jpg)
Sandy soils = Low fertility.Improve fertility with organic matter.Soil pH affects nutrient availability.Best pH range is 6.0 to 6.5.Apply lime to acidic soils.Apply sulfur to alkaline soils.It is not practical to acidify soils
containing lime rock or shell.
![Page 47: Thomas Obreza Soil and Water Science Dept. Univ. of Florida Soil Fertility and pH.](https://reader035.fdocuments.net/reader035/viewer/2022062407/56649d9c5503460f94a85a16/html5/thumbnails/47.jpg)
CreditsAuthor: Thomas ObrezaDepartment: Soil and Water SciencePhotographs: IFAS Communication ServicesCopyright 2008 University of Florida