Science Buddies: "Ask an Expert"

Hi Mr.Sybee,
Again thanks so much for your clarifications. This is helping me a lot to progress well in my project.

1. As you mentioned, yes I will go over the videos and include those details in my project.

2. Can you please validate my Title, Hypothesis, Question, Rationale and correct me if I am missing something and any verbal change.

Title:
Are Superabsorbent Polymers made out of Orange/Avocado Peels as efficient as Potassium Polyacrylate used in Agriculture and a more Eco-Friendly Biopolymer?
(The Average Fold Change of Water Absorption Capacity for various Superabsorbent Polymers)
(The Effect of various Superabsorbent Polymers on Average Soil Moisture over a period of 21 days)
(The Effect of various Superabsorbent Polymers on Average Plant Growth over a period of 21 days)

For science fair, they are expecting us to mention the graph title along with the title. Since I have 3 experiments for my projects, there are 3 graphs. Are the graph titles appropriate?

Hypothesis:
If types of superabsorbent polymers (Potassium polyacrylate, orange/avocado peel powder, and orange/avocado peel mixture) are compared for water retention ability, soil moisture efficiency, and plant growth efficiency, then the amount of water absorbed, soil moisture after 21 days, plant growth after 21 days would be high for Orange peel mixture and as efficient as Potassium polyacrylate.

Question:
When types of superabsorbent polymers like Potassium polyacrylate, Orange/Avocado peel powder, and Orange/Avocado peel mixture are compared for the water retention ability, soil moisture efficiency, and plant growth efficiency, will the amount of water absorbed, soil moisture after 21 days, and plant growth after 21 days be high for Orange peel mixture and as efficient as Potassium polyacrylate?

Rationale:
I wanted to do this project because biodegradable superabsorbent polymers is a highly debated subject. During my research, I found that with anticipated water stress in the future due to population growth, climatic changes, and environmental irrigation factors, hydrogel agriculture technology has been introduced. Hydrophilic polymers could store water and nutrients and release them in drought conditions in light soils. Therefore, an acceptable crop yield with less irrigation could be achieved. I learned that synthetic SAPs involves some toxic residual byproducts and it is expensive (USD3000-3500 per ton). It should be used as per the prescribed dosage. The process to mix potassium polyacrylate is very difficult for common farmers. Recently there are efforts to develop "natural" or fully biodegradable SAPs that might circumvent these limitations. Therefore, SAPs based on polysaccharides are attracting increasing attention lately. This project attempts to investigate if superabsorbent polymers made out of orange/avocado peels are as efficient as and more environmentally friendly than potassium polyacrylate. I really attempted to look at this because during my research it surprised me to see how global climatic anomalies, drought, and deficient precipitation has occurred across the globe in varying scales of severity and how that impacted agriculture.
3. Regarding growing plants, yes I am doing that. I got mini green house as well.

4. My first experiment is water absorption capacity, second experiment is effect on soil moisture, and third would be to check on the plant growth.

5. For second experiment, I am proceeding with the below steps:

o 3 biodegradable cups are filled with 3/4 top soil and 1/4 with each of the SAP. 1 cup is filled fully with top soil (for control testing).
o Saturate each of the 4 cups with 50 ml of distilled water
o After 21 days test the soil moisture in each of the 4 cups with soil moisture tester.

Please confirm if top soil is fine to use since I thought normal potting soil will have other fertilizers needed for growth that would change the readings.


6. For third experiment, I checked for mini plants. But I am not getting as expected. So I am planning for the below steps:
o 8 biodegradable cups are filled with top soil ( 2 cups with potassium polyacrylate, 2 cups with orange/avocado peel powder, 2 cups with orange/avocado peel mixture and 2 with no SAP)
I am taking 8 cups for each trial ( 2 with each SAP and 2 with no SAP). I am planning to germinate lima bean seed in each cup. I am taking additional cups so even if one seed does’nt germinate, I can use the other cup.
o I am planning lima bean seed in each cup. After germination, I am checking the height of the plant in each cup after 21 days.

Please suggest/correct me if I am missing something. Usually since lima bean takes less time to germinate, I chose this method to check the growth. Is it ok?

Thanks,
Lakshita

Hi Lakshita,

I am impressed with your skill in creating a great project and write-up. I hope you do decide to go into science. It is a very satisfying career and I think you would be very good at it.

Here are my revisions and (hopefully) answers to all your questions. Please feel free to disagree and use your own ideas. In some cases the grammar was wrong and had to be corrected, but in others I chose different words or eliminated some for clarity and readability. This is sort of a personal preference, so do follow your own style ideas.

Title
Are Superabsorbent Polymers made out of Orange/Avocado Peels as efficient as Potassium Polyacrylate used in Agriculture and a more Eco-Friendly Biopolymer? I think your title is too long for a person to easily take in so I shortened it:

Eco-friendly, super-absorbent polymers made from orange and avocado peels—are they good for agriculture?


Figure Titles
The figure title should also be short. You can give the details of the experiment in the caption to the figure.
(The Average Fold Change of Water Absorption Capacity for various Superabsorbent Polymers)
Water absorption by super-absorbent polymers, average fold-change.
(The Effect of various Superabsorbent Polymers on Average Soil Moisture over a period of 21 days)
Effect of super-absorbent polymers on soil moisture.
(The Effect of various Superabsorbent Polymers on Average Plant Growth over a period of 21 days)
Effect of super-absorbent polymers on plant growth.

Hypothesis:
If types of superabsorbent polymers (Potassium polyacrylate, orange/avocado peel powder, and orange/avocado peel mixture) are compared for water retention ability, soil moisture efficiency, and plant growth efficiency, then the amount of water absorbed, soil moisture after 21 days, plant growth after 21 days would be high for Orange peel mixture and as efficient as Potassium polyacrylate.
A hypothesis needs to be in the form of a statement about what you expected to happen: The orange/avocado peel mixture shows greater water retention and plant growth compared to orange/avocado peel alone or polyacrylate.

Question:
When types of superabsorbent polymers like Potassium polyacrylate, Orange/Avocado peel powder, and Orange/Avocado peel mixture are compared for the water retention ability, soil moisture efficiency, and plant growth efficiency, will the amount of water absorbed, soil moisture after 21 days, and plant growth after 21 days be high for Orange peel mixture and as efficient as Potassium polyacrylate?
I think your question is also a little too long. Details like the length of time are best kept in the methods section. People looking at a poster like to read simple, direct statements.
Here’s my version of the question: How do orange/avocado peel formulations compare to the super-absorbent polymer, polyacrylate, in terms of water retention and effect on plant growth?

Here is my edited version of your Rationale:
Rationale:
I wanted to do this project because biodegradable superabsorbent polymers (SAPs) are a highly debated subject. During my research, I found that with the anticipated water stress in the future due to population growth, climatic changes, and effects of irrigation on the environment, hydrogel agriculture technology has been introduced. Hydrophilic polymers store water and nutrients and release them in drought conditions in light soils; therefore, an acceptable crop yield could be achieved with less irrigation. I learned that synthetic SAPs for agricultural use can be contaminated with toxic byproducts. They are also quite expensive (USD3000-3500 per ton) when used at the recommended level and the application process would be difficult for small farmers.

Recently there have been efforts to develop cheaper, biodegradable SAPs based on natural polysaccharides that might circumvent these limitations. In this project, I investigated whether superabsorbent polymers made from orange/avocado peels were as efficient as synthetic potassium polyacrylate at water retention while being more environmentally friendly. I chose to look at this question because during my research it surprised me to see how much global climatic anomalies, drought, and deficient precipitation have occurred across the globe in varying degrees of severity and how that has harmed agriculture, especially in developing countries.

5. Plain bagged soil should be fine for experiments 2 and 3, just check the label to make sure there is no fertilizer or water-holding ingredients added.

6. Bean seeds are perfect for your third experiment as they usually germinate well and the plants are vigorous growers. They do like a warm soil to germinate, however, so after planting the beans you should put the cups in a place where the daytime temperature is 22-28C. Also, beans need at least 6 hours of sunshine each day to grow properly so try to keep the pots in a south-facing window—but not too hot.

Good luck and keep posting!

Sybee

Hi Mr.Sybee,
Thanks so much for your compliments. Yes I will be studying science in my college. My parents wants to opt for medicine. But I love forensic/astronomy. I took Bio-Med in my school. Based on the job options and after talking with counsellor, I will choose the right subject to my interest. I am also in music (vocal) which my passion as well. So I will choose a career, that won’t disturb my musicals. I am confused still.
I noted down all your corrections. I will update based on your suggestions.
Regarding step 2 and step 3, thanks for clarifying. I will work on step 2 and step 3 this week end simultaneously.
I will keep you posted on what I see and will send you my other documentation for your review as and when I complete.
Thanks,
Lakshita

Wow! Music, forensics and astronomy--what a great combination. I like them all. Forensic archeology is really cool. Seeing reconstructions of Neanderthals makes me wonder what they were like. Probably not that different from us with regard to the basics. Astronomy and astrophysics are incredibly interesting too (Neil Tyson and Michio Kaku are two of my favorites) but quite daunting because of the advanced math needed to master the subject. Good luck and keep me posted on your progress.

Let me know the outcome of your experiments and if you have any questions at all, be sure to send them right away. I hope you are successful with the stat tests because those are absolutely essential in science.

All the best,
Sybee

Hi Sybee,

Thanks so much for your support and compliments. Definitely I will keep you posted on my career as well.
Regarding statistical tests, I have gone through little. But not really. I will make sure to include them in my project.

Can you please validate below and let me know if any corrections – Application to Life, Variables, Background information.

Application to Life:
When most people look at an orange peel as fodder for the trash can, the innovative product “Orange/Avocado peel mixture” (prepared using orange skin as the main element, and adding some lemon juice and avocado crust to the mix) is an all-natural and inexpensive alternative to the non-biodegradable super-absorbent polymers currently used to improve water retention in soil. This can be a revolutionary agricultural idea that could impact the African continent exponentially and could play an integral role in managing the effects of droughts (ex. starvation, economic losses). The solution is cheaper with a retail price of under $30 to $60 per ton and also proven to be a more effective water reservoir than existing SAPs. If the idea is commercialized and applied to real farms and real crops, the impact that drought has on crops would be reduced.

Variables:
Independent Variables: Type of Superabsorbent Polymers (Potassium Polyacrylate, Orange/Avocado peel powder, and Orange/Avocado peel mixture)
Dependent Variables:
The Average Fold Change of Water Absorption Capacity for various Superabsorbent Polymers
Average Soil Moisture for various Superabsorbent Polymers over a period of 21 days
Average Plant Growth for various Superabsorbent Polymers over a period of 21 days

Constants: Environmental location, Type of water (distilled water), Type of Oranges/Avocadoes/Lemon juice (Organic), Brand of Potassium Polyacrylate (H2OEcoGreen), Weight of each Superabsorbent Polymer (2 grams), Type and size of pots used (Jiffy Pots 4 inches), Type of soil (Top Soil), Brand of Potassium Polyacrylate (H2OEcoGreen), Amount of each Superabsorbent Polymer(2 tablespoon), Type of seeds used (Lima bean)

Control Group: Top Soil with no Superabsorbent Polymer added

Background Information:

Hydrogels are macromolecular cross-linked hydrophilic polymer chains. The most commercially successful hydrogels are superabsorbent polymers (SAPs/superabsorbent hydrogels). It can absorb water up to several hundred times of its own weight and turn into the natural gel from within seconds.
Polyacrylate is the principal material used in the SAP industry. Superabsorbent polyacrylates are prepared from acrylic acid and a crosslinker by solution or suspension polymerization. The type and quantity of crosslinker control both the swelling capacity and gel modulus.
Differences between 2 types of commercial synthetic superabsorbent polymers:
- Sodium polyacrylate will be decomposed into sodium salt which cause soil salinization and hence bad for soil.
Potassium polyacrylate (root watering crystals or water retention granules) contains Potassium, Phosphorus, and Nitrogen that releases the fertilizer efficiency slowly.

- Sodium polyacrylate is an absorbent material of diaper, sanitary napkins, etc.
Potassium polyacrylate is a water retaining agent for plants and soil amendment for improving soil physical and chemical properties.
Drawbacks for synthetic SAPs:
- Current manufacture is expensive
- It involves some toxic residual byproducts.
- It is expensive (USD3000-3500 per ton) per square feet. It should be used as per the prescribed dosage. The Process to mix Potassium Polyacrylate is very difficult for common farmers.
- Its absorbing capabilities reduces, if the water contains salts or any type of electrolytes.
- Current SAPs are all cross-linked by mean of chemicals which means they are NOT BIODEGRADABLE

There are efforts to develop "natural" or fully Biodegradable SAPs that might circumvent these limitations. SAPs based on polysaccharides are attracting increasing attention lately.
Commonly used natural polymers on day-to-day basis:
Gelatin: Jell-O, a brand name, is in general made by heating gelatin (processed collagen) in water.
Pectin: It is a heteropolysaccharide sugar found in the walls of plants which can be used as a gelling agent, especially in jams and jellies. Although many plants have pectin, the peel of citrus fruits such as oranges is particularly rich in pectin.
Websites and books researched:
“Hydrogel - an Overview | ScienceDirect Topics.” Sciencedirect.Com, 2015, www.sciencedirect.com/topics/materials-science/hydrogel. Accessed 23 Dec. 2019.
“What Are Super Absorbent Polymers (And Are They Safe?).” Hello Natural Living, 7 Mar. 2017, http://www.hellonaturalliving.com/what- ... they-safe/. Accessed 9 Dec. 2019.
“Post | Alsta Hydrogel.” Alsta Hydrogel, 2019, http://www.hydrogelagriculture.com/sing ... -Potassium. Accessed 23 Dec. 2019.
“Biopolymer - an Overview | ScienceDirect Topics.” Sciencedirect.Com, 2016, www.sciencedirect.com/topics/chemistry/biopolymer.
Arnon, Hadar, et al. “Development of Polysaccharides-Based Edible Coatings for Citrus Fruits: A Layer-by-Layer Approach.” Food Chemistry, vol. 166, Jan. 2015, pp. 465–472, http://www.sciencedirect.com/science/ar ... 4614009479, 10.1016/j.foodchem.2014.06.061. Accessed 23 Dec. 2019.
“Emulsion Polymerization | Chemistry | Britannica.” Encyclopædia Britannica, 2019, www.britannica.com/science/emulsion-polymerization.
Books:
Kumbar, Sangamesh, et al. Natural and Synthetic Biomedical Polymers. Amsterdam;
Boston, Elsevier, 2014.
Reicosky, Don. Managing Soil Health for Sustainable Agriculture. Volume 1, Fundamentals. Cambridge, Uk, Burleigh Dodds Science Publishing Limited, 2018.

Thanks really for your time.
Lakshita

Great job! My edited copy is attached with some corrections in grammar, word choice and punctuation.

I had a question about the pots. Were they the kind of Jiffy pot made with peat? If so they can lose moisture quickly because of the wicking effect of the peat. It would be better to use a standard 4” plastic pot like what you buy nursery plants in.

Another question was about your statement that the H2OEcoGreen potassium polyacrylate: “…contains potassium, phosphorus, and nitrogen…” If it contains nitrogen and phosphorus as well as potassium, it will act as a fertilizer to stimulate plant growth. Check the label and if it contains fertilizer don’t use it.

When you have finished your write-up of the methods, results and conclusions, send those and I will edit them also.

Make it work!

Sybee

Lakshita,
One thing I forgot to mention was that I used Word's Track Changes when I edited your copy. I always use the Track Changes option for editing because then you can easily compare the original to the edited copy. I hope you know how to use it. If not there are plenty of online tutorials and I can answer any questions you have. Just be sure that you accept or delete the changes so that the editing marks don't show up in the printed copy.

Sybee

Hi Mr.Sybee,
Again thanks a bunch for your time and patience with me. Thanks for correcting my write-up. That really helped me.
- Yes I used word track to note down the changes.
- Yes sure, I will use plastic pots
- I wrote the statement about H2OEcoGreen potassium polyacrylate from google for my background information. When I saw the label I don’t see any mention about phosphorous and nitrogen.
- Yes I will write my other sections of write up and send it you this weekend.
I really hope this project should turn out good as expected. Will keep you posted.
Thanks,
Lakshita

You are certainly welcome, Lakshita. I try very hard to write scientific English clearly and accurately so that even a nonscientist can understand most of it. Keep sending your write-up and I will continue to help by making suggestions. And if there is anything that you are not sure about or want more information on, please ask. When the judges ask you questions, I want you to be able to answer them thoughtfully and accurately.

Oh--there's something I just thought of to tell you, although you probably have already thought of it. The polyacrylate and the orange/avocado preparations will absorb water from the atmosphere so they need to be stored in airtight containers like mason jars with tight sealing lids. You probably are doing that, but I just thought I better say something to make sure because this could definitely alter the experimental results.

All the best,
Sybee

Hi Mr.Sybee,
Yes I got lot of minute details from your write-up. Thanks really for your time. You already mentioned me about storing polyacrylate in mason jars and I did that already .
I started with my second and third experiment. Can you please clarify the below:
1. For the experiment testing soil moisture retention over the period of 21 days, my question: Is it ok for me to record the soil moisture on 0 day and at 21st day or do you think I need to record for every 7 days so it will be for 0, 7, 14 and 21 days.
I was thinking to record for 0,21 days . For graphical representation, show that graphically as bar graph just the soil moisture for 21 days for 3 SAPs.
But in the data table, record for control and 3 Saps and show for 0,21 days. Please provide your thoughts.
2. Similarly for the third experiment, plant growth over the period of 21 days, my idea is to record plant height after germination and again record the plant height on 21st day. Is it ok?
or do you think I need to record for every 7 days so it will be for 0, 7, 14 and 21 days.
I was thinking to record for 0,21 days . For graphical representation, show that graphically as bar graph just the plant height for 21 days for 3 SAPs.
But in the data table, record for control and 3 Saps and show for 0,21 days.

Let me know your suggestions so I will proceed accordingly.
Thanks,
Lakshita

Hi Lakshita,

I'm glad you are thinking about the presentation of experimental data. It is important to show the results in a way that people can easily grasp and understand. In my scientific career I have been accused of going overboard in collecting too much data--more time points than are really needed. But it has often happened that an event occurred during the experiment, like a peak followed by a drop-off, that I would have missed if I had only taken readings at time zero and at the final time.

So I think you can guess what I'm going to tell you--take the additional readings at 7 and 14 days! Really, in my opinion, you can't have too much data. Also, from an aesthetic standpoint plotting several time points that you can connect with a curve looks more convincing than 0 and 21 days. Statistically, a set of experimental points can be fitted with a curve by using a mathematical formula and two curves can be compared as an additional way to prove a difference.

I'm glad you appreciated my changes to your write-up. In addition to my other duties, I am a professional editor and manager of a company that reviews and improves the English in scientific manuscripts for researchers whose native language is not English. That is why I am able to take someone's writing and revise it according to correct English standards and good readability. Good communication is as important in science as rigorous experiments and I try to accomplish both. That is why I emphasized that you should learn about statistics.

Enough preaching! I want you to have fun and enjoy science too. Finding out new facts and stories that nobody else has seen is incredibly exciting and satisfying. The truth is all around us. We just have to train our brains to see it.

Keep posting!

Sybee

Hi Mr. Sybee,
Thanks for your clarification. Also I am glad, you are reviewing my write-up and making changes. As far as your insight into science, I completely agree! I enjoy the fact the science discovers why and how the world works around us! This is also why I want to pursue a career in the field. Thanks for your time. I'm lucky to have you as my mentor!

Regarding the data, I am planning to include standard error and standard deviation, along with mean, in my data table, but not on the graph. I am not planning on creating a statistical graph with curves to shows the progression over time. I will definitely look at it next year! I am planning on doing a bar graph. I think putting data from 0, 7, 14, and 21 days can be a little overwhelming for the audience to interpret easily. Taking this to mind, I want to simply put the soil moisture level at 21 days on the bar graph for each of the 3 SAPs. For the control group, I'm planning on including its data only on a table--not a graph. Is this okay? Please let me know if I'm having a proper thought process with respect to the bar graph.

Thanks,
Lakshita

Hi Lakshita,

If you look at scientific papers published in the journals, certain kinds of data are always presented over a time course. This inclusion of data is important and usually required or the journal will not publish the paper.

In your case, a time course will make the trends for water retention and plant growth easier to see. Instead of just bars, you will plot each mean as one point with standard error bars above and below the mean value and connect the points with a line curve. This can easily be done on Excel and is really the best way to show the data.

Sybee

Hi Mr. Sybee,
Thanks for your clarification. I think I got it, but will send you my finished graph for checking. I will add standard error, standard deviation, and mean to both the data table and graph.

Thanks,
Lakshita

Hi Lakshita,
Thanks for checking. I want your project to be the best you can make it.

You can put standard deviations and standard errors in the table showing your data, but on the graph only use standard error (abbreviated SEM = standard error of the mean). If you put SD and SEM on the graph, it might be confusing. When you use Excel to plot the data, each mean will be one point on the curve and each point will have error bars one SEM above and one SEM below. This spread indicates to the viewer where the 95% confidence interval extends. Two means may look different, but if their error bars overlap, they probably are not different. That is when you do a statistical test to compare the two means to decide if they really are different.

I will help you with this later and you can watch some video lectures that explain about this until it becomes clear in your mind. I keep saying how important these statistical analyses are in science, and it is true as you will see. Your teacher will agree, and can also help you with specific questions and on using Excel if you are not familiar with it. There are other graphing packages with stat calculations, but most people have Excel and it will do almost everything for a basic analysis.

Good luck!

Sybee

Hi Mr.Sybee,
Really thanks for providing insight on statistical analysis. I was going through some videos. Also I already started my second and third experiment. I am also planning to take help from my math teacher if I am not sure on how to plot the graph. I will keep you posted where I am.

Can you also please review the below procedural steps. I am continuing to write the rest.

Procedure:

The below points were considered before performing the experiment:

• When preparing biodegradable superabsorbent polymers from orange peels, lemon juice was added to lower the pH of the mixture and neutralize the negative charges on the polysaccharide strands of pectin, so they assembled into a network and formed gel.
• Avocado peels containing natural oils was added to orange peels containing previously extracted pectin, enabling Emulsion polymerization. The process forms micelles (very small molecular containers that are hydrophilic on the outside and hydrophobic on the inside) and super-long pectin polymers absorbing lot of water.
• For measuring any product weight using a digital weighing scale, initially the weight of the container was recorded and then the weight of the product was calculated by subtracting the weight of the container from the combined weight of the product and the container.


Step1: All the required materials were gathered.


Step2: Preparation of Biodegradable superabsorbent polymers:
 19 Organic oranges were taken, peeled (including as much pith as possible), and finely cut.
 100 ml of organic lemon juice, measured using a graduated cylinder, was added to the orange peels and left for 2 hours.
 1000 ml of distilled water, measured using a graduated cylinder, was added to the finely cut orange peels and lemon juice mixture and kept on the stove for heating. The timer was switched on as soon as the liquid began to simmer and the time taken for the peels to be softened was noted for personal reference.
 The mixture was strained overnight using a kitchen sieve with fine wire mesh.
 9 organic avocados were peeled, finely cut, and added to the cooked orange peels.
 The orange/avocado mixture was sun-dried indoors until the peels were fully dried. The total weight of the sun-dried peels was taken using a digital weighing scale and half the weight was crushed into a powder in a grinder/mixer. This crushed orange/avocado peel powder served as one biodegradable superabsorbent polymer and was stored for experimental purpose.
 The remaining sun-dried peels were mixed with 250 ml of the strained liquid and the combined mixture was dried in the conventional oven for 15 mins.
 The oven-dried mixture was crushed into powder in a grinder/mixer. This crushed orange/avocado peel mixture served as the second biodegradable superabsorbent polymer and was stored for experimental purpose.


Step 3: Measuring the Average Fold Change of Water Absorption Capacity for various Superabsorbent Polymers (Potassium polyacrylate, orange/avocado peel powder, and orange/avocado peel mixture):
 2 grams of each of the three polymers (Potassium polyacrylate, orange/avocado peel powder, and orange/avocado peel mixture) were weighed and taken in the individual graduated cylinders.
 Distilled water was added to each cylinder until the SAP could no longer hold. For accuracy, any excess water was pipetted off.
 Each of the water-swollen polymers were weighed and the fold change (final /initial weight) was recorded.
 The above steps were repeated for trials 2 and 3 and the readings were recorded.

Thanks,
Lakshita

Hi Mr.Sybee,

I finally plotted graph to start with 0 days (initial value). The attached excel is for soil moisture retention experiment (0 days).

- Can you please check and correct me if I am going wrong anywhere.
- Please clarify if SD and SE in data table can be rounded off to tenth decimal as I have done here.
- I haven't modified the title, legend and labels. This is just for your reference to make sure if I am proceeding with graph in correct direction

Thanks for your time.
Lakshita

You're doing great, Lakshita! I'm impressed with your talent.

Rounding off the mean, SD and SE is perfectly OK as you did it. The SD and SE should not have more significant figures than the mean.

The graph of the soil water retention data should use symbols, not bars. The x-axis will be time in days (0, 7, 14 and 21) and the y-axis will be whatever units the moisture meter reads in. Each of the four conditions will have a different symbol and the standard ones used in scientific journals are: open circles, filled circles (black), open triangles and filled triangles. There are many other symbols that could be used but these are the standard ones that most journals require.

Set up the graph with the axis labels and input the data as you get it over the three week period.

The plant growth experiment will have a graph similar to this one except for a different y-axis.

The data from the experiment to compare the water-holding abilities of the three SAPs can be shown as a bar graph with fold-increase in weight on the y-axis and the SAPs on the x-axis.

Good luck, and do keep me updated on your progress.

Sybee

Hi Mr.Sybee,
Thanks for your clarification. Sure I will do and plot as you mentioned. So I guess my SD and SE is correct right?
Also can you please check my procedure write up that I have sent you before my previous post and let me know if any changes?
I am working on writing limitations for this project. Can you please help me with any limitations for this project you think of? I am also working on it and future study for this project.
Thanks for your help.
Lakshita

Hi Lakshita,

I did not calculate the SD and the SE, but since you used Excel they will be correct. The readings are very close, so the SD and SE are small.

Sorry I missed your other message last time with the procedures. I have edited them and the doc is attached. I made some more suggestions that you can consider.

Let me know as soon as you get some water retention data. I am really curious to know how good your polymer preparations are. Remember to keep them dry so they don't absorb any water before the experiment.

The limitations would be primarily with regard to what scientists call scale-up, the taking of a small lab procedure and increasing it to an industrial scale for bulk production. If you think about what would be involved, a factory would need a machine to peel the oranges and avocados (or in countries where money is scarce, this could be done by people), a source of heat to simmer them, a strainer and an area for drying them, then a grinder to make the powder, and a packager to seal the mixture into air-tight bags. Tests would need to be done to determine the shelf-life of the SAP and how long its water retention properties would last in the soil. Remember, there are bacteria and fungi in the soil that can digest organic matter and they might find your orange peel product quite tasty.

I'm sure there are other limitations, like the source and cost of the oranges. If the remains of oranges after juicing could be used, a deal could be set up with an OJ processor to take their orange waste and turn it into a soil amendment. The orange waste might be acquired for the cost of hauling it away.

Keep posting! You are doing great.

Sybee

Hi Mr.Sybee,

Thanks so much for your time checking my write up and providing suggestions. I looked into it and made changes as needed. Again, I am really lucky to have you as my mentor.

Sure I will send you all the readings.

Can you also please check on the below write up for the additional procedure steps and provide your suggestions:

Step 4: Measuring the average soil moisture retention of potassium polyacrylate, orange/avocado peel powder, and orange/avocado peel mixture over the period of 21 days:

 Four planting pots were filled three-fourths full of top soil and 2 tablespoons of each of the three polymers (Potassium polyacrylate, orange/avocado peel powder, and orange/avocado peel mixture) was added to the three pots. One pot, used for the control group, was left with no added SAP.
 Each of the 4 pots was saturated with 50 ml of water. Initial soil moisture for each pot was recorded using a soil-moisture meter (with scale of 1-10, 1 being most dry and 10 being most wet)
 On the 7th, 14th and 21st day, the soil moisture for each pot was again recorded using a soil-moisture meter.
 The above steps were repeated for trials 2 and 3 and the readings were recorded.


Step 5: Measuring the average plant growth with potassium polyacrylate, orange/avocado peel powder, and orange/avocado peel mixture over the period of 21 days:
 Four planting pots were filled three-fourths full of top soil and 2 tablespoons of each of the three polymers (Potassium polyacrylate, orange/avocado peel powder, and orange/avocado peel mixture) was added to the three pots. One pot, used for the control group, was left with no added SAP.
 One Lima bean seed was planted in each of the 4 pots and saturated with 50 ml water.
 All the 4 pots were kept in the indoor greenhouse and monitored on a day-to-day basis.
 On the 7th, 14th and 21st day, plant height (in centimeters) in each was recorded.
 The above steps were repeated for trials 2 and 3 and the readings were recorded.


Thanks,
Lakshita

You are certainly welcome, Lakshita! Good job so far.

I edited your experimental steps and made some suggestions based on the way scientists usually approach a project like this. If you have questions, please let me know.

Sybee

Hi Mr.Sybee,

Thanks a lot for your comments. I made changes as suggested by you to my procedure. I will keep posted on my progress.

Thanks,
Lakshita

Happy to help you!

If you have ANY questions at all, don't hesitate to post them. Practice describing your project and the results to a friend or sibling and make a note if you get stuck or your listener says they don't understand so you can make a change to eliminate the confusion. Making diagrams or flow charts of your experiments that you c an post on your science fair board helps when you are talking about them. And, of course, take lots of photos and print the ones that show your experimental setups and results.

Good luck!

Sybee

Hi Mr.Sybee,

Yes I am taking step by step photos as you mentioned and working on data tables/graphs. I have started with my log book as well. Thanks again for all your time and valuable feedback without which this project would not have come to this point.

Can you please check on the below for limitations and Further study which will be added to my conclusion:

Limitations:
One limitation or error that could have occurred throughout the experiment would be the fluctuations in temperature and humidity which were not considered but may have resulted in better/worse polymer quality and variabilities of results. Another limitation would be the organic method opted for triggering emulsion polymerization (adding natural oils from avocado peels and pectin from orange peels) which couldn’t be controlled since more precise measurements were not considered. A third limitation would be measuring just the “degrees of moisture” in the soil using a soil moisture meter that estimates the volumetric water content in soil. For more precise measurement, it might be better to reconsider the measurement using a gravimetric method which requires removing, drying, and weighing the sample. This could give a precise percentage of water in a given volume of soil.

Further Study:
If I were to continue and advance this experiment, I would test the orange peel super absorbent polymers’ performance in different soil types and test to see if they could be used to create an oasis in the desert. I would also like to see how they react with different types of liquids, as we know that it is not always water that gets poured into the soil. I would like to test how these superabsorbent gels react to fertilizers, pesticides, gasoline, or other toxins and if it would create a concentration of toxins that could get into our food. As superabsorbent polymers have a very absorbing future, I would be thrilled to do my part in joining the water conservation effort to quench the thirst of the arid Earth.

Thanks,
Lakshita

It is my pleasure to help you, Lakshita. You are doing all the work--I'm just the guide. I hope you will call on me again in the future for your next project.

I like your writing especially the future studies section where your voice really comes through. You should get up in front of the United Nations along with Greta Thunberg and present your case for creating "oases in the desert". I'll bet they would pay attention!

Good luck!

Sybee

Hi Mr.Sybee,

That means so much to me! You really have been more than a guide though. I can't imagine doing this project and any future projects without you. I will definitely keep you updated on any future experiments. I will keep the United Nations stuff on my mind though I have taken your suggestions and changed my limitations and further study. I will keep posting my questions.

Thanks,
Lakshita

You are so welcome, Lakshita. I will be happy to continue as a virtual mentor to see you well embarked on a joyful scientific career. I always wanted to help people but did not feel I had the makings of a medical doctor, so went into research and teaching instead. You can make a real positive contribution to people's happiness and well-being through your dedication to solving an environmental problem like water shortage, which is only getting worse with climate change and over-population.

Keep reading and educating yourself and thinking about what most interests you and I will continue to be here as a guide and giver of advice.

All the best,

Sybee

Hi Mr.Sybee,
Sure I will definitely be in touch with you on my career plans. I am so happy to let you know that my plants are growing and I am making good progress tracking the readings, and writing log book. Can you please review the below write up on my reflections.
Reflections:
After my research and experiment on biodegradable superabsorbent polymers made out of Orange/Avocado peels, I was thinking how important it was to successfully make farmers aware of this inexpensive way to create mini reservoirs of water in the soil, and overcome the drought in agriculture. The polymer has the added benefit of sustainability as it uses recycled and biodegradable waste products. In addition, efforts to reduce the use of commercially based SAPs in agriculture must be expanded on how these hazardous, nonbiodegradable and extensive use causes environmental problems.

I suddenly got doubt while plotting graph. I remember, you mentioned to use SD and SEM in the data table and in graph plot only SEM right?

I am following the below steps while plotting SEM on graph. Please correct me if I am wrong.
- I am selecting more error bar options
- Vertical Error bar (both), End style CAP
- Custom specify value (specify SEM value) for both positive and negative error value

Please let me know if this is correct. Why I am confused is I am getting only small error bars on top of each bar. Is that right?

Thanks so much for your time. Sorry I have not been introduced to SD and SEM in school and I learnt by myself which is confusing me.

Thanks,
Lakshita

Hi Lakshita,

I am so happy to hear that you made the effort to learn about means and standard deviations and SEM on your own--yaay! That's what I hoped you would do. I just wish I was there to answer your questions so that you would not be confused. Eventually you will reach the point where it all makes sense, and that is a great feeling. If you will post some of your raw data or upload the Excel file, I will take a look at it and let you know what I think about the error bars. If your SD is very small then your error bars will also be small, which is good because it means your readings are very consistent.

I read over your reflections and made a few minor corrections--otherwise, very nice!

Reflections:
After finishing my research and experiments on biodegradable superabsorbent polymers made from orange and avocado peels, I was thinking how important it was to reach out to farmers and make them aware of this inexpensive way to create mini-reservoirs of water in the soil, and to overcome the effect of drought on their crops. The polymer has the added benefit of sustainability as it recycles waste products that would otherwise be thrown away and it is biodegradable itself. In addition, the availability of a good substitute would enhance the efforts to reduce the use of commercial SAPs in agriculture so that these expensive, hazardous, non-biodegradable chemicals will not causes further environmental damage.

Keep up the good work, Lakshita. I am proud of you!

Sybee