Allie+Faivre

The Effectiveness of Different States of Agricultural Lime on Soil pH

Problem: Does the state of agricultural lime applied on soil affect how well it raises the pH of the soil?

Background: Many farmers use nitrogen-based fertilizers that make the soil acidic. (What is leaching exactly? -Eleanor) Leaching, different crops, and pollution also play a role in making soil acidic (Hill 4). (What is leaching? - Sarah Beth) Because acidic soil is bad for crops, farmers apply agricultural lime to the soil to make it less acidic. (Why is acidic soil so bad for raising crops? -Eleanor) The agricultural lime has calcium and magnesium carbonates that counteract the hydrogen ions that make the soil acidic (Beegle 1). To have a successful cash-grain system, soil needs to have a pH between 6.0 and 7.2 (Chapter 83). There are many different choices for agricultural lime, also known as aglime. Chemical purity, magnesium content, moisture, and state of matter are some factors that affect the quality of the aglime. “[Equivalent neutralizing value] is a measure of the effectiveness of the material… calculated by multiplying the [calcium carbonate equivalent] by a factor based on the fineness of limestone" (Beegle 12). Liquid and solid aglime are both available, along with different sizes of solid aglime. There are pellets, powders, chunks, et cetera (Seeger 11). Liquids have no definite shape, so they can move around and soak into the soil easier. Solids have a definite shape, so in order to be completely used, it would have to break down from the outside-in. The speed at which the agricultural lime breaks down would influence the effectiveness of the agricultural lime on the soil pH (Wilbraham 36). Another way speed is involved is in the spreading of the agricultural lime. The tractor's speed would affect how evenly the aglime is spread. If the tractor moves too fast, there could be spots without any aglime added, which would not help neutralize the soil. However, if the tractor goes really slow, it would not be worth the cost of gas to spread the aglime. After the agricultural lime is spread, many farmers till the soil. Tilling causes force, which could break up the aglime, causing it to break down faster. Also, it mixes the lime into the soil, which also speeds up the reaction. The agricultural lime is surrounded by soil that needs to become less acidic.

Hypothesis: If liquid agricultural lime is applied on moderately acidic soil, it will work more effectively than a solid agricultural lime. Work more effectively in terms of making the soil even less acidic? Perhaps make this hypothesis more specific in terms of pH, speed, or cost (whichever you are going for) rather than using words like 'effective' that can have a lot of different meanings! (Bri Mosher)

Materials: Total: $434.54
 * 1 Digital pH Probe ($41.95)
 * 7.5 mL Liquid Agricultural Lime __($___) Would the liquid lime and the solid lime go through different process to get them into the farmers hands? So would like the compitsion of the two types be a little different? (Savanah Weston)
 * 5g Solid Agricultural Lime __($___)
 * 22.5 m 3 Dr. Earth Natural and Organic Potting Soil ($11.33) (If someone was replicating this experiment, would the type of potting soil change the results dramatically? Does it have to be this type exactly? What makes this one better than another type of soil? -Eleanor)
 * sixteen 150mL beakers ($5.00 each x 16= $80)
 * one 125 mL flask with stopper ($30 )
 * 4.5 L distilled water ($12)
 * 1 balance and weigh boat ($207)
 * 1 scoopula ($2)
 * 1 graduated pastette (transfer pipette) ($19.21)
 * 1 pair of safety goggles ($5.05)
 * 10 pairs of gloves. (between $4-$10)

Methods:
 * 1) Put on all safety equipment.
 * 2) Gather all materials. Maybe be more specific with what equipment and what materials. (Savanah Weston)
 * 3) Label 5 beakers “Solid AgLime”.
 * 4) Label 5 beakers “Liquid AgLime”.
 * 5) Label 5 beakers “Control: No AgLime Added”
 * 6) Separate soil out into 15 groups of _g.
 * 7) Place each group into its own labeled beaker.
 * 8) Evenly spread __1.0g__ solid aglime on the soil labeled “Solid AgLime”.
 * 9) Evenly spread __1.5m__L liquid aglime on the soil labeled “Liquid AgLime”.
 * 10) Keep soil moist, but not wet. How are you going to manage how moist the soil is, could this effect the data of someone trying to replicate your experiment later on? (Savanah Weston) In order to keep the soil the same moisture all the time will you have to control how much water goes into the soil at all times as well as what room temperature is/how it may differ throughout the day? (Sarah Beth)
 * 11) Let soil sit for one week to allow aglime to break down.
 * 12) Use a solution to quantitatively measure the pH of the soil.
 * 13) Using a scoopula, weigh boat, and balance, measure out 5g of soil. How are you going to collect the 5 g from the beaker? Ms. Miller
 * 14) Transfer the 2.5 g of soil into the 125 mL flask with stopper.
 * 15) Add 50 mL distilled water to the 2.5 g soil.
 * 16) Put the stopper on the flask.
 * 17) Shake the flask for one minute.
 * 18) Let it settle for one hour.
 * 19) Transfer the solution to a 150 mL beaker.
 * 20) Use the digital pH probe to test the pH of the solution. Record.
 * 21) Repeat steps 11-12 with each beaker of soil once a week.
 * 22) Repeat steps 10-13 until the pH of the soil is between 6.0-7.0.

How is the pH test strip going to be a qualitative measurement? Is there number readings that correspond with words that will make 13.1-13.9 qualitative data? (Bri Mosher)

http://www2.ca.uky.edu/wkrec/pH-Ammonia.htm

Works Cited

Ball, Jeff. "Understanding and Correcting Soil Acidity." Understanding and Correcting Soil Acidity. Samuel Roberts Noble Foundation, n.d. Web. 24 Oct. 2013.

Beegle, Douglas B. Soil Acidity and AgLime. University Park, PA: Pennsylvania State University, 1995. PDF.

"Chapter 11: Soil Testing and Fertility." Illinois Agronomy Handbook, 1999-2000. Ed. Phyllis Picklesimer. Urbana, IL: University of Illinois at Urbana-Champaign, College of Agricultural, Consumer and Environmental Sciences, Dept. of Crop Sciences, University of Illinois Extension, 1998. 78-87. Print.

Hill, Stephen. "MPA - Mineral Products Association - Products." Mineral Products. Mineral Products Association, 2013. Web. 18 Oct. 2013.

Mitchell, Charles C. "Soil Acidity and Liming Overview." //Clemson Crop and Soil Environmental Science Extension //. Clemson University, n.d. Web. 20 Feb. 2014.

Pullinger, Eileen. "In This Section." Lime Effectiveness. Agricultural Lime Association, n.d. Web. 22 Oct. 2013.

Pullinger, Eileen. "PH Value and Lime Requirements." Ph Value and Lime Requirements. Agricultural Lime Association, n.d. Web. 22 Oct. 2013.

Seeger, Arleen. "Lime Basics FAQ." Lime Basics. National Lime Association, n.d. Web. 22 Oct. 2013.

Wilbraham, Antony C. Pearson Chemistry. Boston, MA: Pearson, 2012. 36. Print.