Conclusion- Michael Savio

        I think both Kristen and I had our ups and downs in this lab, but overall it was an interesting and insightful experience. Needless to say I now know a lot more about soil than I had in the past (who would've guessed that dirt is different than soil?) and am glad to learn more about what I'm stepping on everyday. I for one never really thought about the fact that there are millions of microorganisms that live and function in the soil, hence making soil in fact alive. I also learned just what makes soil fertile and able to grow crops through all the labs and then in the remediation and controlled experiment labs. The labs helped me understand the fundamentals of soil and its various components.
        People should be more aware of the dangers of soil overuse in agriculture. We use so much soil in agriculture nowadays and use the soil more than we're able to replenish it, and if we don't slow down our production and use it sustainably, we could end up not being able to feed large portions of the world. Although I was absent for most of the salinization lab, I know that the amount of salt we put into the soil can cause many problems for the soil and can cause it to lose its fertility. Like many of our natural resources, soil is a part of the environment we take for granted, and we are in serious jeopardy of losing it in the near future if we don't change our agricultural practices.
        The lab was sometimes tiresome work, but I think it allowed us to learn about soil in an intriguing and effective way. And although sometimes I may still call it dirt, I'll know deep down that it is and always will be soil.
        Also, I am responsible for the remediation, berlese funnel, soil fertility analysis, and soil porosity posts while Kristen is responsible for all the others.

Kristen's Conclusion

This lab focused on the composition of soil and tests that one can do to learn more about what is in the soil. Many things can influence how well things grow in soil like whether it is clay or sandy which influences water drainage. During this lab I have become more aware of how much thought goes into different aspects of soil. Before this I did not know that things like pH in soil mattered to the health of the soil and organisms growing in it. I knew that soil had living organisms but I did not know how influential these were in the development of the soil and how all the different layers were made.The most important part of the lab I think was learning how to test for different chemicals because it’s important to know how much is already in your soil. As we learned earlier a lot of the chemicals in soil like nitrogen and phosphorus are important in keeping the environment healthy, and we need to use these sustainably. By knowing how much the soil has you can tell how much is needed so that there isn't an excess amount being used. I think it is important for people to know this along with the benefits of using different fertilizers because paying attention to what’s being put in your soil is something easy to do unlike some things like the porosity which are more time consuming to figure out. Although organic is seen as better it also has down sides because there's no way to know exactly what is being put in the soil. 

Salinization

In the salinization test we were assigned to create a bag of 4g/100mL concentration of salt for each lab table. Since we had to use 120mL of water we used the equation 4g/100mL=Xg/120mL to figure out the amount of salt we would need to keep the proportion the same. This came out to be 4.8g of salt so we mixed this in with 120mL of water. Then we put one paper towel with beans on top and poured 20mL of water into each of the 6 bags. In order to also compare red vs white beans we were to split up 3 bags of white and 3 bags of red beans. With our own bags we observed that the only growth was seen in the 0g of salt concentration bag. However, in other groups the .5g beans were also growing just as well and one group even had the start of a root breaking through in a 2g bag. 

.5g concentration

Overall, the higher concentrations were incapable of growing and most were even molding and had a green color to them. The same patterns in growth seen in the red beans were seen in the white beans.

This led us to the conclusion that things can not grow if there is too much salt. In order to remediate salty soils you can add sulfur, add carbon to reduce soil dispersion and the amount of sodium. Also tilling and leaching the soil can help.

white beans with .5g concentration

Controlled Experiment

remediated (left) control (right)

Despite our efforts, in our experiment our controlled soil grew better than our remediated soil. It was close because both were growing but the lettuce in the controlled cup was taller and was beginning to grow faster. The lettuce in our remediated soil was limp and beginning to fall over whereas the lettuce in our controlled soil was much more straight up. We predict this is because in our efforts to help our remediated soil flourish we smothered it with too many chemicals. However neither of our soils produced very good lettuce as both only had three of the seeds grow and each only had two leaves at the top. The leaves of both were a light green and the stems were an off white with a tint of a greenish hue. They grew at about the same slightly below average rate but towards the last couple of days the controlled soil was distinctly becoming taller. Lettuce tasting different could be because of many factors. The location that the soil was from could have an impact because different organisms and factors influenced the development of the soil and the composition. We knew going in that we had soil that was at a disadvantage and had little life or beneficial characteristics due to where we had collected it from. Our lettuce probably would taste very toxic because we had to add chemicals in lrder to even the playing groun with the other soils. the taste Of remediated soil it could have changed based on different chemicals added. Depending on how much fertilizer was put in or if the fertilizer was organic or inorganic could effect the taste.

control (left) remediated (right) on the last day

Remediation

      Our soil was not exactly as fertile as we would have hoped. Through the results of our tests, we found that our soil was low on nutrients, organic matter, and life, which isn't extremely spectacular for growing crops, but it is also at a good neutral pH and a silt-loam complexion, which are more beneficial traits. So our focus for creating the best possible soil for our lettuce centered around adding more nutrients to the soil to support the plant's growth.

The two variables (before adding fertilizer)

       But first, we needed to decide exactly what traits we wanted to enhance in our soil. Looking at the tests we'd done on our soil, we found that because of the data from our berlese funnel test (there were no living organisms in our soil) we definitely needed to do something to create the best possible conditions for our plant to grow. We looked at the results from the soil texture tests and the percolation rate tests and found that the soil most likely has mostly a silt or silt-loam texture because the data from the qualitative and quantitative tests pinpoint a silt-like complexion and the data from the percolation rate test shows us that our soil was more similar to clay than sand but was not extremely close to that of clay. Our soil having a more silt-like texture was favorable in our opinion because we did not want the soil to be too sand-like or clay-like to detract from the growth rate of the lettuce, so we decided not to alter the soil texture. We also looked at the results from the percent organic matter test and correlated it with the soil fertility analysis to find that the low organic matter may be a factor of how low the soil's nutrients are. Organic matter contributes to the foundation of the soil's nutrients because without organic matter, the soil cannot take in as many nutrients and becomes less fertile.
      Taking these results into consideration, we decided that it would be best to use inorganic fertilizer to give our lettuce the best chance of not being terrible. That doesn't sound super positive. I meant to say, to give our lettuce the best possible chance of being the best gosh-darn lettuce the world has ever seen! That's slightly better, maybe a little overdone, but let's keep this optimistic.

Stop! Hammer time

      Anyway, because our lettuce has such low nutrient levels, we decided to use the inorganic fertilizer because we felt that it would be better to use specific known amounts of nutrients that would be added into the soil instead of organic fertilizer in which we'd have no idea the exact amounts of what we were adding to our soil. We didn't need to add anything to alter the pH because we thought a pH of 7 would be sufficient, we didn't add anything to the soil texture because we thought soil with mostly silt would be good for growing this type of seed, and we didn't add any more organic matter because we thought that adding more nutrients would be more helpful than adding more organic matter.

The two variables (after adding fertilizer)

      In our remediated soil, we added Vigoro fertilizer to add the essential nutrients we needed. The control soil weighed 262.7 grams and the remediated soil weighed 260.4 grams to begin the lab, and we appropriately added 12.8 grams of Vigoro into the water we used to water the remediated soil. We used 20 mL of water each day (except on days we were off school) to water the two plants, and we left the plants in natural sunlight each day.
       We expect that the lettuce made in the remediated soil will be healthier and tastier than that of the controlled soil because of the nutrients added. Let's hope the remediated soil lettuce will be less terrible than the other. I'm sorry, I mean both of them will be fantastic, but maybe the lettuce with the enhanced soil will be even better!

Berlese Funnel

Our beautiful bottle of soil

      Our Berlese Funnel test was set up correctly and carried out in accordance with the correct procedure; however, we found no organisms. In the ethanol from the petri dish there was nothing living that could be seen by the naked eye. Each day, the bottom of the soda bottle had a little more soil that had fallen through the funnel, but not enough that it would throw off the results of the experiment, so I think our soil sample just didn't have any macroinvertebrates.

Looking good under the lamp

     
      When we were collecting the soil, we found some insects and worms that were in the soil, but somehow (as in through human error) we had none of these organisms in our soil sample. In particular, we saw earthworms in our soil when we collected it, and these organisms' function is to recycle nutrients and carbon in soil. We didn't see any other distinct organisms that were in the soil, but the worms do play an important role in the formation of soil.

No organisms :(

      After discussing the lab with other groups in the class, many had similar results as us in the fact that they had either very few organisms or none at all. This could be a result of many different scenarios, but perhaps it could be because of the fact that each group's collected soil was unfertilized and may have had less nutrients than nutrient-heavy soil that would attract and contain more macroinvertebrates. This overwhelming lack of organisms creates a pattern throughout the class of low levels of macroinvertebrates in the soil.


     

Soil Fertility Analysis

Savio shaking his groove thang

     The fertility analysis revealed information about how well our soil will be able to grow plants. The soil responded to the tests in various ways and helped us understand the positive and negative traits of our collected soil.

Phosphorous test

      We started with the phosphorous test, which showed us that there were only trace amounts of phosphorous in our soil. In our nitrogen and potassium tests, the results were not very encouraging either: the nitrogen test results showed us we had trace amounts of nitrogen in our soil, and because the potassium test took so many droplets of the solution to turn the other solution a light blue color, it was revealed that we had low levels of potassium in our soil (0-120 lbs/acre). All the nutrients we tested for in the soil were at low or very low levels, which does not bode well for producing crops in this soil. Because the soil was unfertilized, we now understand why so many farmers use fertilizers on their crops because if they had soil like ours then it would be much more difficult to grow productive crops with soil with low nutrient levels.

pH test

Potassium test

Cuba Marsh

     Our pH test had a more positive result. Through the test, we found that our soil's pH level was very close to precisely 7, meaning that the soil was very neutral, neither too acidic nor too basic. In the area of Cuba Marsh in which we collected our soil, there were mostly grasses and some trees, but not an incredibly abundant amount of plant life. The plants did not necessarily look healthy around us, but the season was turning towards winter when we collected the soil so it may have been that the plants were changing in accordance with the seasonal change. However, most plants need a soil pH of between 5.5 and 7.0 to truly thrive, so I think the pH level of our soil is good, and most plants that can survive in this climate could live in this soil based solely on its pH level (in terms of nutrients and formation perhaps not so much). The grasses and trees around the area in which we collected our soil were surviving and were successful based on the soil pH but may have looked not as healthy due to seasonal change or the low nutrient levels in the soil.