The florida lime study
This presentation is the property of its rightful owner.
Sponsored Links
1 / 21

The Florida Lime Study PowerPoint PPT Presentation


  • 43 Views
  • Uploaded on
  • Presentation posted in: General

The Florida Lime Study. Rao Mylavarapu, Nancy Wilkinson, William d’Angelo, Jennifer Frey, Cassandra Admire, Alex Bournique, Murthy Kadiyala Soil & Water Science Department, IFAS University of Florida. Objective.

Download Presentation

The Florida Lime Study

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


The florida lime study

The Florida Lime Study

Rao Mylavarapu, Nancy Wilkinson, William d’Angelo, Jennifer Frey, Cassandra Admire, Alex Bournique, Murthy Kadiyala

Soil & Water Science Department, IFAS

University of Florida


Objective

Objective

  • Screen methods for determination of lime requirement for acid-mineral soils of Florida

  • Methods

    • University of Kentucky- Sikora method

    • Auburn University - Huluka method

    • Clemson University - Sikora-Moore method

    • University of Georgia- Single Titration method


Justification

Justification

  • The current Adams-Evans Buffer method involves p-Nitrophenol, an environmentally hazardous chemical

  • An environmentally friendly alternative method is needed

  • Primary need, however, is to identify a method that will be effective for acid-mineral soils of Florida


Materials and methods

Materials and Methods

  • Collected 12 soil samples from 10 different counties-

    Bradford, Clay, Columbia, Highlands, Hendry, Lake,

    Marion, Sumter, Putnam (3 samples) and Jackson counties

  • Samples were dried, sieved through 2.0mm mesh

  • The 4 methods were replicated 4 times

  • Water pH (1:2) was determined on all samples

  • Soil pH ranged from 4.0 to 5.4

  • AE-Buffer pH was determined and the Target pHs were identified as 6.5 and 6.8


Materials and methods1

Materials and Methods

  • Four replicates of each sample, weighing 200 grams, were sent to each state Lab

  • Each Lab ran their preferred method and determined the lime requirement and returned the data

  • Calcitic lime was added to all cups as per the recommendation from each of the state labs and the cups were incubated in the dark for a total of 63 days


Preparation

Preparation

  • The experiment was replicated 4 times

    • 200 g of sample was weighed into each cup

    • Labeled with county, Lab, lime rate and replicate

    • 12 counties labeled from A to L

    • 4 Labs were labeled I, II, III, IV

    • Lime rates for a Target pH of 6.5 were labeled as 1 and for a Target pH of 6.8 were labeled as 2


Preparation1

Preparation

  • Pure CaCO3 was added to the cups as prescribed by each Lab for Target pHs of 6.5 and 6.8, after converting from

    Lb Acre-1 to g cup-1

  • Soils was stirred well for homogeneity

  • All the sample cups were maintained at 30% moisture content for the entire duration of incubation by estimating the bulk density and pore space

  • The samples were weighed regularly and water was added using syringe inserted into a straw, which stayed inserted thru the incubation period, to bring the moisture content back to 30%


The florida lime study

Incubating cups were checked for any moisture loss through evaporation by weekly weighing

Water was injected slowly into the incubating

cups by a syringe inserted into a straw reaching the bottom of the cups to replace the moisture


Incubation

Incubation

  • All samples were kept in the dark and in a climate-controlled area at 72°F for 63 days for incubation


Post incubation

Post-incubation

  • All the straws were removed and the soils were stirred and let them dry for a couple of days

  • Determined the water pH (1:2) by subsampling the cups for 20 grams of soil and adding 40 ml of water.


The florida lime study

Results


The florida lime study

Lime requirement calculated for 6.5 target pH by different methods


The florida lime study

Lime requirement calculated for 6.8 target pH by various methods


The florida lime study

Measured pH after application of lime for target pH of 6.5


The florida lime study

Measured pH after application of lime for target pH of 6.8


The florida lime study

Average pH values measured after lime application


The florida lime study

Average target pH values measured in various county samples


The florida lime study

Take home messages

  • All the methods have over-estimated the lime requirements as indicated by the increase in pH beyond the Target pH at the end of the incubation period

  • Differentials in Target pHs were not realized even with different lime recommendation amounts, for any of the methods

  • Soil pH determinations showed a high amount of variation, with possible statistical significance in certain cases

  • Other soil physical and chemical parameters may be influencing the lime efficacy

  • Field calibrations may further increase the variability


Conclusion

Conclusion

  • There is a method that Florida can use……

    OR

  • There is no method that can be clearly identified as suitable

    AND

    Repeat the study with a few modifications !


  • Login