S&S 12.1 Soil Nutrients and Fertilizers GLEs , 3.1.3, 3.2.4

Lesson Target Compare the nitrogen [N] content of two different soils and discover how well each soil absorbs nitrogen [N] from fertilizer

Testable Question How does the type of soil [potting soil OR local soil] affect the amount of nitrogen that can be absorbed?

FYI Like all living organisms, plants need nutrients to survive and grow The soil in which a plant grows is the source of most of these nutrients Like all living organisms, plants need nutrients to survive and grow The soil in which a plant grows is the source of most of these nutrients

SOIL A mixture of rock, mineral particles, and organic matter; mixture of living and non-living matter

SOIL FERTILITY The ability of soil to store nutrients in a form that can be absorbed by plant roots [Some soils are naturally more fertile that others] The ability of soil to store nutrients in a form that can be absorbed by plant roots [Some soils are naturally more fertile that others]

FERTILIZERS Substances rich in plant nutrients that are often used to increase the fertility of soils, especially soils used to grow agricultural products

Fertilizers cont. Fertilizers commonly contain nitrogen [N], phosphorus [P], and potassium [K]. These 3 elements are essential for plant growth Fertilizers commonly contain nitrogen [N], phosphorus [P], and potassium [K]. These 3 elements are essential for plant growth

Fertilizers cont. Farmers have used naturally occurring decaying organic matter, such as manure and compost, as fertilizers, because they contain abundant supplies of N, P, and K, as well as other essential nutrients.

Fertilizers cont. The increased crop yields of today are due to the use of MANUFACTURED fertilizers, which are mixtures of chemicals produced at factories These fertilizers are expensive because fertilizer production is a costly, energy-intensive process The increased crop yields of today are due to the use of MANUFACTURED fertilizers, which are mixtures of chemicals produced at factories These fertilizers are expensive because fertilizer production is a costly, energy-intensive process

In this Activity… You will test fertilized and unfertilized soils for the presence of nitrates [NO 3 - ], the form of nitrogen most easily used by plants. You will also test the nitrate level found in the runoff water that is not absorbed by the soil You will test fertilized and unfertilized soils for the presence of nitrates [NO 3 - ], the form of nitrogen most easily used by plants. You will also test the nitrate level found in the runoff water that is not absorbed by the soil

RUNOFF Runoff often ends up in streams, lakes, and other bodies of water, including reservoirs that provide drinking water. You will convert the nitrates to nitrites [NO 2 - ] and then allow them to react with a dye that turns pink in the presence of nitrites. Runoff often ends up in streams, lakes, and other bodies of water, including reservoirs that provide drinking water. You will convert the nitrates to nitrites [NO 2 - ] and then allow them to react with a dye that turns pink in the presence of nitrites.

PROCEDURE PART A - Testing Soil 1. Label on vial A and the other B 2. Place 1 g potting soil into A and 1 g local soil into B 3. Add 5 mL of nitrogen extraction solution to each vial, cap and shake for 1 minute PART A - Testing Soil 1. Label on vial A and the other B 2. Place 1 g potting soil into A and 1 g local soil into B 3. Add 5 mL of nitrogen extraction solution to each vial, cap and shake for 1 minute

PROCEDURE cont. 4. Set the vials aside until most of the solids have settled out and the liquid is clear enough to see through 5. Using a pipet, transfer 3 mL of the liquid from vial A to Cup A on the SEPUP tray 4. Set the vials aside until most of the solids have settled out and the liquid is clear enough to see through 5. Using a pipet, transfer 3 mL of the liquid from vial A to Cup A on the SEPUP tray

PROCEDURE cont. 6. Rinse the pipet and transfer 3 mL of the liquid from vial B to Cup B on the SEPUP tray 7. Add 10 stir-stick scoops [0.5 g] of Nitrate Testing Powder to Cup A and stir to mix. 8. Rinse and dry the stir stick and Add 10 stir-stick scoops [0.5 g] of Nitrate Testing Powder to Cup B and stir to mix. 6. Rinse the pipet and transfer 3 mL of the liquid from vial B to Cup B on the SEPUP tray 7. Add 10 stir-stick scoops [0.5 g] of Nitrate Testing Powder to Cup A and stir to mix. 8. Rinse and dry the stir stick and Add 10 stir-stick scoops [0.5 g] of Nitrate Testing Powder to Cup B and stir to mix.

PROCEDURE cont. 9. Let the mixtures stand for 5 minutes. 10. Clean up all of your other dirty lab equipment so it is ready for Part B of this Investigation. 11. After 5 minutes, estimate the Nitrogen content of each sample using the Nitrogen Color Chart 9. Let the mixtures stand for 5 minutes. 10. Clean up all of your other dirty lab equipment so it is ready for Part B of this Investigation. 11. After 5 minutes, estimate the Nitrogen content of each sample using the Nitrogen Color Chart

PROCEDURE PART B - Testing Runoff 1. Use a clean SEPUP tray, funnel, and filter paper to prepare a filtering setup that will drip into Cup D of your tray PART B - Testing Runoff 1. Use a clean SEPUP tray, funnel, and filter paper to prepare a filtering setup that will drip into Cup D of your tray

PROCEDURE cont. 2. Fill the filter paper cone with with local soil, then SLOWLY pour 5 mL of fertilizer solution over the soil. Allow the fertilizer solution to percolate [filter gradually] through the soil and drip into Cup D

PROCEDURE cont. 3. Transfer 1 mL of the runoff liquid that collects in Cup D to Vial A, then transfer 1 g of the fertilized soil in the filter paper cone to Vial B 4. Add 5 mL of nitrogen extraction solution to both vials; cap and shake each vial for 1 minute 3. Transfer 1 mL of the runoff liquid that collects in Cup D to Vial A, then transfer 1 g of the fertilized soil in the filter paper cone to Vial B 4. Add 5 mL of nitrogen extraction solution to both vials; cap and shake each vial for 1 minute

PROCEDURE cont. 5. Set both vials aside until most of the solids settle out and the liquid in Vial B is clear enough to see through 6. Using a pipet, transfer 3 mL of the liquid from Vial A to Cup A 7. Rinse the pipet and transfer 3 mL of the liquid from Vial B to Cup B 5. Set both vials aside until most of the solids settle out and the liquid in Vial B is clear enough to see through 6. Using a pipet, transfer 3 mL of the liquid from Vial A to Cup A 7. Rinse the pipet and transfer 3 mL of the liquid from Vial B to Cup B

PROCEDURE cont. 8. Add 10 stir-stick scoops [0.5 g] of nitrate testing powder to Cup A and stir to mix 9. Rinse the stir stick, then add 10 stir-stick scoops [0.5 g] of nitrate testing powder to Cup B and stir to mix 8. Add 10 stir-stick scoops [0.5 g] of nitrate testing powder to Cup A and stir to mix 9. Rinse the stir stick, then add 10 stir-stick scoops [0.5 g] of nitrate testing powder to Cup B and stir to mix

PROCEDURE cont. 10. While these mixtures stand for 5 minutes, clean up your lab materials. 11. After 5 minutes, use the Nitrogen Color Chart to estimate the nitrogen content of the soil sample AND the runoff liquid 10. While these mixtures stand for 5 minutes, clean up your lab materials. 11. After 5 minutes, use the Nitrogen Color Chart to estimate the nitrogen content of the soil sample AND the runoff liquid

Conclusions Write conclusions for this Lab Investigation, as instructed by your teacher. Write conclusions for this Lab Investigation, as instructed by your teacher.