Save the Soil

Testing for the most effective method to prevent flat farmland soil erosion from elemental factors. Factors include wind, rains, and flooding.
Arya Shetye
Grade 7

Hypothesis

Of the three widely known methods for farmland soil erosion - Erosion Control Blankets, weighing down the soil and fibre logging, an ECB is the most effective way to prevent soil erosion because of its fibrous, strong, widespread area that in turn protects the plants underneath.

 

Research

 

SOIL EROSION & LOSS OF PRECIOUS TOP SOIL

 

“After the mass agricultural disaster known as the Dirty 30s, drought conditions on the Prairies are once again raising the risk that farmers’ valuable topsoil will go blowing in the wind,” warned a recent article in The National Post

 

Severe erosion events and their increasing frequency cause dry and windy conditions and stir up dust clouds posing driving hazard and filling up irrigation canals to the brim with dirt.  But they do much worse by reducing agricultural productivity, both by removing nutrients fom the fields it flows from and by spreading weeds and damaging crops where it lands.

 

Both elemental factors such as wind, flooding and rain, and now increasingly man-made factors such as over ploughing and construction, are driving massive soil erosion. These factors result in the loss of topsoil turning perfect farmland into a wasteland. 

BLOW TO AGRICULTURE ECONOMY

Farming and agriculture contribute $7.5 billion to the Alberta economy. With eroded soil, the economic balance is in jeopardy, devastating not only the farmers, but the entire population. as it directly impacts our primary source of sustenance in the form of farm produce we consume.

A 2019 study published by the European Commission’s Joint Research Center put the estimated annual impact of erosion on global GDP at US$8 billion.

As per a 2016 study by University of Manitoba researcher David Lobb, the soil loss due to erosion costs the Canadian agriculture industry $2 billion a year in lost productivity.

                                                           EROSION CONTROL TECHNIQUES AND METHODS

 Natural interventions such as reforestation, cover cropping and plant rotation have existed for a long time. Planting trees and vegetation can cut down on erosion by a much as 75%. It is also a way to stabilize earth flows, gullies and shallow landslides that are actively eroding.Planting a cover crop when the soil is otherwise bare after the cash crop is grown, keeps the soil to the ground maintaining the living roots.

Erosion Control Blanket, or an ECB is made from a compound of jute, coir, straw, and excelsior fibres, the mix is then matted into its blanket form. Usually, an ECB is 1-2 inches thick. It prevents soil from shifting off and also give the undergrowth time to grow roots and stimulate long time growth.

Weighing down the soil:  This protects the young plants by acting as an armor against water runoff that could potentially sweep away topsoil. Using mulch and rocks is less expensive than ECBs, but at the same time can be unsustainable if used incorrectly. 

Fiber Logging: Made from jute matting and wood excelsior, this log is most effective on hillside/angled farms. It will allow runoff to come down, but rather than letting mud/wet topsoil slide down, it soaks the rainwater into the soil. Fiber logging, like ECBs, can be expensive, but many farms are now using up the hillside land to account for more plants and livestock. 

Importance of Erosion control

“Erosion control can definitely contribute to the economy by maintaining the productivity of the land, thus reducing the amount of chemical inputs needed to produce a crop. In addition, erosion control helps protect water bodies such as streams, rivers and lakes by reducing the amount of pollutants such as nitrogen and phosphorus from fertilizers entering these systems.”

How do erosion control methods help agriculture

“By using erosion control methods such as ECB and fibre logging, more topsoil is retained and less money has to be spent on soil amendments or importing soil. This means lower costs to the farmer which would then mean more money in their pockets. By treating erosion at the source, rather than trying to deal with the consequences of erosion, such as soil loss, they can focus on growing and perhaps even have more available area to grow crops.”

WHY SOIL EROSION CONTROL ESPECIALLY MATTERS TO ALBERTA

Alberta is often characterized as an oil-rich province with beautiful golden prairies and panoramic mountain landscapes. But what many people miss is that it is also an agricultural powerhouse!

Farming in Alberta has been happening for well over a century. With its nutrient-rich soil, the province is now a leading producer of canola, wheat, dry peas, barley and cattle, and is expanding its food processing capabilities. Alberta's arable lands, extensive irrigation network and abundance of sunshine make it an ideal region to produce agricultural products of all sorts.

Alberta has the most land classified as prairies-  vast tracts of flat and rolling plains. Most of Canada's crop farming takes place in the Prairie provinces (Alberta, Saskatchewan and Manitoba).

 

 

 

 

Variables

Manipulated: Types of soil erosion prevention methods

 

Responding: Amount of soil erosion that occurs


Controlled: Model scale farm size, plant type (wheatgrass), area of testing (Garage)

Procedure

 

Materials needed ~ Organic wood excelsior, Indoor Potting Soil Mix, a spray bottle filled with water, 3 (34.5cm x 24.6cm) aluminum lasagna pans, all organic Coir fiber, organic burlap matting, small wood chip mulch (ideally crafted for soil fertility), a MAINSTAYS pedestal fan, a cookie tray 3 centimeters larger around the perimeter of the lasagna pan, a 2x2 liter pop bottle, a washcloth, a 19 L Home Depot bucket, a small container, and a controlled room for the experiment.

 

PROCEDURE TO BUILD MODEL:

  1. Gather all materials needed
  2. Take the lasagna pan and cut 4 incisions into the corners of the pan. These incisions should create 4 flaps as shown in the picture below. Fold the flaps fully downwards to look like the model in the picture.

 

 

  1. Take about 7 cups of the soil and put it into the tray.
  2. Dampen the soil.
  3. Evenly spread about 1 ½ handfuls of the microgreen seeds. Make sure to get lots in the center and around the edges as these spots tend to have stunted growth. 
  4. Lightly massage the Chia seeds into the soil about a centimeter downwards.
  5. Water the Chia seeds.
  6. Place the model in a spot with full sun and in close proximity (not directly over) to a radiator.
  7. After 1-2 weeks of consistent watering at least thrice a day, the Chia should be sprouted and suitable for testing.

 

PROCEDURES TO MAKE FIBER LOG

  1. Lay the burlap sheet flat.
  2. Measure out two 20x30 and two 10x20 sheets with a ruler and pen
  3. Cut out all four sheets.
  4. Take the wood excelsior and lay it flat onto the four sheets.
  5. Tightly roll the burlap and excelsior into a log and secure with three burlap strings.

 

PROCEDURE FOR SETTING UP TESTING AREA:

  1. In a controlled room (preferably a large one with no external elements), set up a foldable table large enough to fit the model farm and other supplies
  2. Place the cookie tray underneath the model farm.
  3. Nearby, keep the hanger on a washcloth.

 

PROCEDURES FOR TESTING: (Make sure to run a mock test beforehand with NO prevention methods atop the farm model.)

Wind ~ 

  1. On the testing table, arrange the cookie tray so that it is underneath the model farm. 
  2. Place the fan so that it will be directly in front of the model farm.
  3. Set a timer for 15 minutes.
  4. Turn on the fan to the maximum setting (1400 CFM) and let it run for 15 minutes. Start the timer as soon as you have started the fan.
  5. After the timer goes off, survey the erosion done by the wind and record data on a separate sheet.

 

Rain ~ 1) Take your 2x2 liter pop bottle and a heated needle. The needle should be very small in diameter (0.7 mm).

            

2) After poking the holes 2 mm apart along the marked lines, take the 19 L bucket and fill it completely with water. 

3) Put the pop bottle into the bucket and walk to the testing area.

4) After having set up the cookie tray underneath again, quickly remove the bottle from the bucket. 

5) Shower vigorously all over the farm model until it has run out of water. (Should last about 2 minutes)

6) Record all data on the erosion on a separate sheet.

 

Flood ~ 

  1. Place the cookie tray underneath the farm model.
  2. Fill the small container with water.
  3. Set up the recording device.
  4.  Start recording. On a 45 degree angle, pour the water downwards slowly so that it “floods” the farm. 
  5. Record the erosion and other data onto a separate sheet.

 

The wind speed was 1201 Cubic Feet per Minute (high speed intensity equal to 156 MPH) 

 

Observations

Wind Erosion Test:

ECB TRIAL ONE

(before starting the test, the wheatgrass was growing proficiently.)

12 minutes in: No visible soil erosion, wheatgrass looked quite unstable.

6 minutes in: Minor debris visible around the bottom left corner of the cookie tray, particle was about 0.8 mm in diameter.

Trial end: Same results as 6 minutes with no changes.

Overall quality after testing: Very good, no visible changes to wheatgrass, only 3 miniscule particles observed.

 

ECB TRIAL TWO

(before starting the test, the wheatgrass looked relatively healthy, save for the few, odd, beige strands.)

12 minutes in: A small particle about 2 mm in diameter was noted in the bottom left corner of the cookie tray, the wheatgrass was stable.

6 minutes in: A small quantity of particles had gathered around the bottom left corner of the cookie tray.

Trial end: All particles had clustered in the bottom left corner of the cookie tray, the rest of the tray was clean.

 

MULCH TRIAL ONE 

(before testing, the wheatgrass looked incredibly healthy.)

12 minutes in: A 2 cm piece of mulch had been blown away and sat in the bottom left corner of the cookie tray.

6 minutes in: Erosion was visible, many particles of soil were noted around the four corners and edges of the cookie tray, the wheatgrass in the center had become dislodged.

Trial end: The center of the model farm was completely ravaged, debris visible around the edges and even on the table itself. This shows that the mulch did not do well against the wind test.

Overall quality after testing: Deficient results, model farm center completely uprooted, many particles of debris including pieces of mulch were noted showing significant erosion.

 

MULCH TRIAL TWO

(before testing, the wheatgrass was growing adequately with some strands growing awkwardly and in a different position on the contrary to the rest due to the changing position of the sun.) 

12 minutes in: A 2 cm mass of soil had flown to the top left corner of the cookie tray, wheatgrass looked quite stable.

6 minutes in: At least 12 particles were noted in the bottom and top left corners of the cookie tray, the wheatgrass in the center of the tray was beginning to slowly rise out of the soil.

Trial end: Several particles were noted in the bottom and top left corner of the cookie tray, while on the right-hand side of the tray, only 9 (exact count) particles were noted. This could be a result of the angle of the fan changing slightly over the course of 15 minutes.

Overall quality after testing: Average (less damage than expected, less damage than trial one), center was again uprooted (trend), larger particles were noted (1 mm - 2 cm).

 

FIBER LOG TRIAL ONE - 

(before testing, the wheatgrass was growing in multiple directions with some strands facing north while others faced east or south. This could be a result of sunlight being blocked out partially from the sun's changing position.)

12 minutes in: No visible soil erosion, wheatgrass looks stable.

6 minutes in: Exactly 3 particles have eroded into the bottom left and right corners of the cookie tray. Wheatgrass, though tangled on the right, looks quite stable.

Trial end: Same results as the 6 minute mark, no changes on the model farm or the cookie tray. 

Overall quality after testing: Adequate, this trial when compared to that of the mulch and ECB was a middle. The wheatgrass remained steady, though erosion by wind did occur.

 

FIBER LOG TRIAL TWO - 

(before testing, the wheatgrass had similar growth patterns like the trial one of fiber logs ; The grass was even more severely tangled. I infer that this was due to the log(s) themselves blocking the sunlight hence creating a mangled growth.)

12 minutes in: A particle 0.7 mm in diameter had eroded into the bottom right corner of the cookie tray.

6 minutes in: Same results as 12 minutes, no changes to the tray or model farm. Wheatgrass looks moderately unstable with some strands on the verge of being uprooted.

Trial end: Only two particles were recorded in the cookie tray, but the wheatgrass throughout the duration of the trial looked unstable. (none were uprooted though)

Overall quality after testing: Satisfactory results with minimal erosion, the fiber logs did a very good job of sheltering the “crops” from the wind!

 

TRENDS:

  1. When wind erosion occurred, the debris almost always eroded into the bottom left corner of the cookie tray. This happened a total of 6 times through all 6 trials with the three soil erosion prevention method types. I infer that this was due to the angle fan which could have been slightly tilted to the left. 
  2. With the fiber log test, both model farms carried wheatgrass with mangled growth, and as stated before in the comments, I can infer that this was due to the changing position of the sun and/or the log(s) themselves blocking out vital rays of sunlight.

 

OUTLIERS: 

  1. On mulch (trial one), the debris had scattered to all four corners of the cookie tray. The mulch trials fared worst against the wind yet I still find it surprising that so many particles scattered to the four corners instead of the usual bottom left. I cannot come up with a reasonable answer as to why this may be.
  2. On mulch (trial two), the debris eroded into the top left corner rather than the bottom left or even the four corners. This, unlike the first trial I do have a reasonable explanation for. When folding the flaps to create the model farm, there could have been a dip near the top left corner causing more erosion to occur.

 

Side note: I was quite surprised at how well the fiber logs fared; Typically they are used on slopes but out of curiosity I wanted to see how they would fare on a flat farm.


 

 


 

Rain Erosion Test ~ 

ECB TRIAL ONE:

(before testing, the wheatgrass was growing neatly and in small tufts.)

The test lasted a total of 1 minute and two seconds. During the test, a puddle of water formed in the center of the model farm. The crops were well protected and did not erode into the cookie tray. Though the coir fiber was completely drenched, it held together in a  strong bond. After the 2x2 liter bottle had emptied, 12 large particles were noted. There was quite a bit of soil scattered around the tray. In conclusion, trial one was a success ; The model farm held up relatively well, the “crops” were well protected and still intact after testing and minimal erosion occurred.

 

ECB TRIAL TWO: 

(before testing, the wheatgrass was bright green and healthy, growing in small, neat tufts.)

The test lasted for 1 minute and 1 second. During the test, a large puddle of water formed in the middle of the model farm. The coir fiber blanket began to lift slightly on the edges, resulting in more erosion. This happened on the left side of the model farm. The crops were protected enough to stand, but more particles of soil eroded into the cookie tray. After the 2x2 liter bottle had emptied, 19 large particles were noted throughout the entirety of the cookie tray. In conclusion, trial two was adequate; while the crops were well protected, if this had been a real farm, the amount of soil lost would have been devastating.

 

MULCH TRIAL ONE:

(before testing, the wheatgrass was growing in neat, healthy tufts.)

The test lasted a total of 56 seconds. Unfortunately, I had to stop the flow of the rain because the erosion was spilling everywhere and caused a huge mess in the garage. Right off the bat, an extremely large puddle formed in the center of the model farm. The wheatgrass seemed to be moving up and down and looked to be teetering every which way. After about 30 seconds, the soil began to rise and eroded heavily into all four corners of the tray. After the 2x2 liter bottle had emptied, it was indistinguishable as to how many particles eroded into the tray. If I hadn’t stopped the water flow, the garage floor would have been covered in eroded soil! In conclusion, trial one was unsatisfactory. Had this been a real farm, the damages would have completely ravaged everything!

 

MULCH TRIAL TWO:

(before testing, the wheatgrass looked healthy and grew in tufts.)

The test lasted for exactly 1 minute. After roughly ten seconds of testing, a hefty puddle formed in the center and right side of the model farm. This caused the soil to swell upwards, and after 20 seconds of continuous rain, spilled into the cookie tray. I may have squeezed a bit hard on the bottle causing an increase in pressure because a portion of the model farm which looked relatively fine eroded swiftly. After the 2x2 liter bottle had emptied, many large particles were noted in the cookie tray. The wheatgrass remained intact. The cookie tray was also spilling out onto the experiment table with excess water. In conclusion, trial two was below par; Although the wheatgrass remained intact, the soil erosion was too much for the model to handle. 

 

FIBER LOG TRIAL ONE:

(before testing, the wheatgrass was again askew. There were slightly visible tufts, but there were plenty of wayward strands growing in all directions in between as well.)

The test lasted for 1 minute and 2 seconds. The logs acted as a barrier for the water creating a pool immediately. The wheatgrass was beginning to erode as well, with some strands floating in the water. After 30 seconds, the water had risen to the top of the logs, but by then the pressure of the rain was dropping due to the decreasing amount of water. After the 2x2 liter bottle had emptied, some medium soil pieces had eroded into the cookie tray. In conclusion, trial one was a partial success. The erosion was less when compared to that of the mulch trials, but the wheatgrass was not protected well enough. On a real farm, crop loss would have a devastating impact on the total yield costs (they would decrease) and recovering the land would also prove costly.

 

FIBER LOG TRIAL TWO:

(before testing, the wheatgrass was exactly the same as the trial one from the rain test. No differences noted.)

The test lasted for 1 minute and 3 seconds. Unlike trial one, the water seeped from underneath the logs, taking some debris alongside. The wheatgrass looked stable, nothing showed signs of being uprooted. The fiber logs were starting to become unsteady, but they didn’t fall over. After the 2x2 liter bottle had emptied, a thin film of eroded soil had accumulated over the cookie tray. In conclusion, trial two was an unsatisfactory trial. Like some other trials, the wheatgrass held steady, but the loss of soil erosion was a tipping factor. Had this been a real farm, the erosion would have had a negative effect on the land itself.

 

Flood Erosion Test ~ 

ECB TRIAL ONE

Water absorption: Good, the wheatgrass remained intact.

Runoff level: The runoff was minimal, but some debris carried with it contained traces of coir fiber.

Debris Amount: Not much, no large, eye-catching debris as such.

 

ECB TRIAL TWO

Water absorption: Adequate, the wheatgrass remained intact however the ECB itself looked to be moving up and down.

Runoff level: Medium, water that ran off the edges embedded with lots of debris though not much water actually ran off.

Debris Amount: Some major debris clustered around the corners, otherwise only a film of small debris sat atop the water.


MULCH TRIAL ONE

Water absorption: Poor, the mulch and soil both eroded quickly. Wheatgrass remained intact.

Runoff level: Heavy, water ran off from the center down carrying heavy debris.

Debris Amount: Lots of large pieces floating in cookie tray, thick film of soil atop the water.

 

MULCH TRIAL TWO

Water absorption: Poor, a puddle formed quickly and eroded carrying lots of debris. Wheatgrass began to uproot.

Runoff level: Heavy, water ran off from center to all directions (like a fountain).

Debris Amount: Chunks of debris floating around in a cluster, thin film of soil atop the water.

 

FIBER LOG TRIAL ONE

Water absorption: Inadequate, due to the barricade-like structure of the fiber logs, a pool of water formed. Wheatgrass began to uproot.

Runoff level: Moderate, with the pool of water, small debris eroded over the edges along with some strands of wheatgrass.

Debris Amount: Only 3 large pieces of debris were noted, otherwise only a thin film sat atop the water.

 

FIBER LOG TRIAL TWO

Water absorption: Poor, again, the barricade like structure of the fiber logs caused water to spill over the edges.

Runoff level: Severe, the water that spilled over the edges was dark brown and ridden with spots of wheatgrass and fertilizer.

Debris Amount: A film of soil, wheatgrass and fertilizer had formed over the entirety of the cookie tray.   

 

Analysis

TRIAL 1

TRIAL 2

AVERAGE LEVEL OF SOIL COHESION. (Scale of 1-5, 1 is compacted soil cohesion, 5 is completely eroded.)

AVERAGE LEVEL OF PLANT INTEGRITY. (Same scale format as the soil cohesion graph.)

 

Conclusion

In conclusion, the soil erosion prevention method that helped protect against the elements on the farm the most was the erosion control blanket. The erosion control blanket used its fibrous, widespreadness to hold the wheatgrass in place. Upon closer inspection, the coir fiber seemed to be interlocked, holding the wheatgrass solidly. This data proves my hypothesis, which states that the erosion control blanket would shelter the “crops” best. Some limitations that occurred were the inconsistent growth of the wheatgrass among the fiber log farm models, the partial decline in growth over the period of time when I went on holiday, and the possibility of farm models being influenced by internal factors such as the temperature of the house (stunted plant growth). In the future, I can solve consistency issues by setting the farm models in a controlled environment where the temperature is always the same. (indoor greenhouse) 

 

Application

Albertan farms on a 180 degrees angle 

- If I suited my project for angled or hillside farms, areas such as Mongolia which are prone to soil erosion would benefit quite a bit

Agricultural Farming in Mongolia - Mongulai

As you can see, Mongolian farmland is also quite flat. The windy conditions would need durable soil erosion prevention methods, like the Erosion Control Blanket to protect the delicate soil beneath.

Sources Of Error

Some limitations that occurred were the inconsistent growth of the wheatgrass among the fiber log farm models, partly due to internal factors such as the temperature of the house (stunted plant growth). In the future, I can solve consistency issues by setting the farm models in a controlled environment where the temperature is always the same (indoor greenhouse) .

 

Citations

Soil and Land use change.

Ryusuke Hatano, Hokkaido University

Soil erosion: causes and effects

October, 2012, Ontario.ca

Soil Health and Management

2021, Laura L. Van Eerd ,Kate A. Congreves, Melissa M. Arcand, Yvonne Lawley and Caroline Halde at OpenPress.usask.ca

(Recommended by expert, article on how soil erosion and other factors impact the overall soil health.)

National Soil Erosion Research Laboratory : USDA ARS

Directory of pedologists, agrologists and soil scientists given to me by Chris Renschler at NSERL.

Soil Erosion Control

By BC.gov

Cover Cropping on the Prairies

April 3, 2023, Mark Halsall, Grainews.ca

Canadian farm soils still on the move

April 1, 2021, Robin Brooker, Producer.com

 

Acknowledgement

Thank you to my family for helping fund the trials, my experts Rich Farell and Caroline Atsley, and my teacher Mrs. Turner for reviewing contemporary errors.