Science Buddies: "Ask an Expert"

Hi Lakshita,

It is really good to hear from you again and I'm glad to hear that you and your family are staying well. Nobody knows when this pandemic will end, so we still need to be cautious. I heard on the news today that the number of cases in several states including Florida started increasing again. It may be because people are being less careful. We are all tired of staying home but we can't act like the virus is gone, because it isn't.

I'm glad you are planning to go for an honor's science project next year. I know whatever you do it will turn out great! I'll have to think about what you said that you were thinking about doing an extension of the SAP project. It is possible, but right off I don't have any ideas about what you could do that would be super interesting. I suppose, you could try the orancado extract on a large garden plot outdoors because this is something that a company would have to do to prove efficacy of the soil amendment under real farming conditions with rain, irrigation, fertilizer, pesticides, etc.

I love to garden myself and I have a big vegie garden. Someday I will make a bunch of orancado and try an experiment growing beans or corn in one plot treated with the soil amendment right next to an untreated plot. You could do that if you have a place in your yard where you can make a garden. Also, I garden organically using compost and manure and this is supposed to help soil hold moisture. It would be interesting to see if an organic garden would benefit from orancado as much as a non-organic plot where chemical fertilizers and pesticides are used, but no soil amendments.

These are just my first ideas, and I would love to hear what you are thinking of. There are many great areas for science research, but you are a little limited this year by not being able to work in the labs. You can do a lot at home, but there are many chemicals and supplies that are only sold to licensed organizations like schools and companies. Let's keep the conversation going through the summer and I'm sure you will be able to come up with a great plan for your next project.

Stay well,
Sybee

Hi Mr.Sybee,

Thanks so much for your email. I am so glad you are willing to help me this year too. Yes, as you mentioned I see cases are increasing in Missouri too. I see many are not wearing masks outside. Are you located in Florida. Yes my mom was saying all beaches are open there .
I am also really happy that you are planning to make orancado mixture for your organic garden. Let me know how that works.
I am also researching how to work on the continuation project. Seems like we have to create additional data tables which means adding new research topic to the existing research. I will write to you once I find something. I am hoping to finalize what I am going to do atleast by the end of this month.

Thanks. Stay safe.
Lakshita

Hi Lakshita,

I'm glad to hear that you and your family are fine. We just don't know what is going to happen. The schools will be opening in Florida in the fall, but the classrooms were already packed so I don't how they are going to fit everyone in and still keep 6 feet apart. Life has enough challenges without this too!

Do keep in touch and let me know what you think would make a good honors project. We will be leaving Florida to head back up to Maine in September, but I will continue to monitor Scibuddies for your questions.

Stay safe and well and happy,

Sybee

Dear Ms.Lakshita,
I have been trying to follow Ms.Kiara Nirghin procedure to make the Orange SAPs for 2 months but the final products can only absorb the water 5-10 times its weight. Are there any steps that I need to change or be extra careful in order for it to work like yours and Ms.Kiara ? I am really confuse right now because I tried to follow each step like it was described. I would be grateful if you could give me guidance regarding the Orange SAPs making procedure.

Thank you for considering my request,
Nathayuth

Hi Nathayuth,

I am sorry the orange SAPs didn't work for you yet. I followed the similar procedure as Kiara. Below are the steps I followed.

• The peels were removed from 19 organic oranges including as much pith as possible and finely cut.
• 100 ml of organic lemon juice, measured using a graduated beaker, was added to the orange peels and left for 2 hours.
 1000 ml of distilled water, measured using a graduated beaker, was added to the finely cut orange peels and lemon juice, and the mixture was kept on the gas 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. This strained liquid was stored in a mason jar inside a refrigerator for future experimental purpose.
 Nine organic avocados were peeled, finely cut, and added to the cooked orange peels.
 The orange and avocado peel mixture was sun-dried indoors until the peels were fully dried. The total weight of the sun-dried peels was measured using a digital weighing scale and half of the weight was ground into a powder in a blender. This crushed orange and avocado peel powder served as one type of biodegradable superabsorbent polymer and was stored in a mason jar for later experiments.
 The remaining sun-dried peels were mixed with 250 ml of the strained liquid and the combined mixture was dried in a conventional oven for 15 minutes.
 The oven-dried mixture was ground into a powder in a blender. This crushed orange and avocado peel mixture served as the second biodegradable superabsorbent polymer and was stored in a mason jar for later experiments.
• The peels were removed from 19 organic oranges including as much pith as possible and finely cut.
• 100 ml of organic lemon juice, measured using a graduated beaker, was added to the orange peels and left for 2 hours.
 1000 ml of distilled water, measured using a graduated beaker, was added to the finely cut orange peels and lemon juice, and the mixture was kept on the gas 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. This strained liquid was stored in a mason jar inside a refrigerator for future experimental purpose.
 Nine organic avocados were peeled, finely cut, and added to the cooked orange peels.
 The orange and avocado peel mixture was sun-dried indoors until the peels were fully dried. The total weight of the sun-dried peels was measured using a digital weighing scale and half of the weight was ground into a powder in a blender. This crushed orange and avocado peel powder served as one type of biodegradable superabsorbent polymer and was stored in a mason jar for later experiments.
 The remaining sun-dried peels were mixed with 250 ml of the strained liquid and the combined mixture was dried in a conventional oven for 15 minutes.
 The oven-dried mixture was ground into a powder in a blender. This crushed orange and avocado peel mixture served as the second biodegradable superabsorbent polymer and was stored in a mason jar for later experiments.

Good Luck on your project.

Thanks,
Lakshita

Hi Mr.Sybee,

Thanks so much for your time. Even I am bit scared to get back to school as there would always be a huge rush of students walking up the staircase while switching classes after each hour. I probably won't share food with my friends like I usually do either. Here in Missouri, they opened second phase since yesterday. I can only imagine the precautions that will be taken during the upcoming school year.

I researched a few things and came up with the below idea. In my previous experiment, I measured the soil moisture using a soil moisture meter. I also mentioned in my limitations that "measuring the “degrees of moisture” in the soil using a soil moisture meter that estimates the volumetric water content in soil. For more precise measurements, it might be better to repeat the readings using a gravimetric method, which requires removing, drying, and weighing the samples. This would give a more precise percentage of water in a given volume of soil".

With that keeping in mind, I came across the below research done by an other student.

http://dissertations.mak.ac.ug/bitstrea ... sAllowed=y

Please go over and suggest me if I can opt this. I am not planning to do any other super absorbent polymers. But my test would be against the three samples which I did in my previous project. Potassium polyacrylate vs orange & avocado peel powder vs orange & avocado peel mixture.

Planning to exhibit the experiment procedure from page 24 of the above link.

The question to test is as the amount of SAP in the soil is increased, will the water retention of the soil also increase? The different SAP to soil ratios are 0:30,2:28 and so on. This is quite obvious statement if we think from the layman perspective. But if you suggest we can take up this experiment since it does soil retention in a more precise method rather than just using soil moisture meter.

Also planning to do biodegradablity test as mentioned in page 28.

Not sure what is the soil textural triangle mentioned in page 23. I am also planning to compare orancado SAP in different types of soil like top soil vs clay vs sand vs silt. The idea here is vague for me. But I sort of understood from the below link.

https://www.nature.com/articles/s41598-019-39412-x

In conclusion it was mentioned as : High SAP concentration decreased the clay content. Does that mean even if SAP amounts are high in the clay still the water retention will be low compared to that of sand?

They also mentioned about mulching. Can you please help me to develop this idea of testing between various soil types and let me know if it sounds interesting? Should we include mulching in our experiment?


Please also suggest if you think of any other ideas or if the above tests seems to be okay as part of the continuation project?

Thanks again for your time,
Lakshita

Hi Lakshita,

I share your concerns about school and keeping distance, which seems almost impossible. Hopefully by the end of the year we'll have a safe and effective vaccine and we can go back to just taking the same precautions we did for colds and the flu.

There's a lot of information and questions in your message, so let me think about it and I will get back to you. I'd like to see you do something really exciting, but under the circumstances with limited access to lab and the uncertainty of things, I guess it is better to keep it simple.

All best wishes,

Sybee

Dear Ms.Lakshita
I do have one batch left that will be tested this saturday. I reallyyyy hope it will work. My project is to compare between the Orange with avocado peels and Orange with kaffir lime peels. But I will have to successfully make the original orange SAPs first. Thank you so much for giving me your updated procedure. Good luck on your project this year too!

Thanks,
Nathayuth

Dear Ms.Lakshita
The last batch that I mention to you in in the other post turn out be be another failed product. This will be my final request to you. Would you be willing to sent me the picture of your step by step process? I still have time for one last attempt and I want to make sure that everything went according to the procedure so that I can find out which step that make my product failed. I am sorry if this request cause you any inconvenience.
Thank you very much
Nathayuth

[Administrator note: Nathayuth - if you have questions about the project you are doing, we recommend you start a new thread to get assistance. Students are not able to provide copies of their projects, photos, or procedures via this forums. Each student does need to do their own work for their projects. And if the project doesn't turn out as expected, you may be able to get troubleshooting assistance in your own thread, but you may also need to report for your own project what happened, what went wrong, and what next steps you might take. Lakshu's photos and documentation of her project are of her individual project. They are not available for re-use.]

Hi Mr.Sybee,

Thanks for your time. How is Florida. Hope you are in Miami now. Sure go over my questions as you find time and please let me know your suggestions. I have scheduled virtual meeting with regional science fair coordinator next week to get more information on Honors rules. I will keep you posted.
I wanted to finalize what I am going to do in another 1 week atleast so I can start thinking on my procedure to do.

Thanks and stay safe,
Lakshita

Hi Lakshita,

I hope things are getting back to normal where you live. Florida has seen the highest number of new cases of the virus ever and that is pretty scary. Fortunately we do NOT live in Miami as that is one of the main problem areas. We are in the north central region near the University of Florida.

I will be getting back to you some time next week with my thoughts on your project. I am glad to hear that you have a meeting with the science fair coordinator. That was a smart thing to do. The rules are probably a little different this year because of the virus. Let me know what you find out.

Best wishes,
Sybee

Hi Mr.Sybee,
Yes my mom was mentioning about increase in cases in Florida and Texas. Please stay safe. Even in missouri, as of yesterday there were many new cases. I am not sure how they will be planning for school in August. Tomorrow I will be going to school for school supplies drop off.
I will definitely keep you posted on what I discuss with Science coordinator this Thursday.

Also regarding this year's project idea, I was going over many more ideas and trying to compile that as well. I guess I am getting some idea to make the project interesting. But definitely I would need your suggestions. I will send that also in couple of days so you can take a look and then we will finalize what we are going to do for this year. Based on that, I will send to science fair coordinator get the topic approved and then I will start ordering required materials and start my project. I am planning to complete the project before summer so I need not worry about weather conditions. Writing part of the project I can start at later time once I get hold of the project.

Thanks again for your valuable time. Stay safe.
Lakshita

Hi Lakshita,

Thanks for keeping me updated about your project plans. I really enjoy reading your messages and I am happy to be able to give you advice and suggestions. I hope your school will be able to hold classroom sessions safely in August. In person interactions really are necessary for full learning. I teach myself and keep my knowledge and skills up by reading journal articles, watching videos and tutorials and attending webinars, but its kinda lonesome and I miss talking to fellow researchers at the lab.

I have been thinking about what you might do with the orancado soil amendment, but aside from my first suggestion of setting up actual test plots outdoors, nothing really sounds that exciting or challenging. You seem to have more ideas, however, and I'm sure your mom offers suggestions so I know you will come up with something good for the honors science fair.

I will certainly help you with working out any details and checking your methods and statistics. I hope you have come to see that statistics is really the backbone of scientific research and the sooner you master the subject, the better for you. Science is a lot of work, but it is also incredibly satisfying and engaging. Einstein used to sit for hours mulling over his thought experiments, then he would go and try to write the equations that would prove his ideas were valid--or not. I wish I were more of a math person but I know my talents are more in observation and building things. A couple of years ago, we build an electrospinner at the lab to make nanofibers and now i have been reading that there's a company that is making antivirus masks out of electrospun nanofibers! They use 3D printers to make the frame of the mask and then attach the nanofiber part as a filter. They are very cheap to make and as effective as N95 masks. I guess I am like you. I want to use my science skills to make something that helps people now.

You stay safe too. Young people don't often get bad cases of COVID-19, but they could pass the virus to someone else so wearing a facemask is always a good idea to protect others as well as yourself.

So, Keep me in the loop as your personal science trainer. I am happy to help.

Sybee

Hi Mr.Sybee,

How are you. Hope you had great and safe July 4th. Here I fired fireworks at home but did't go anywhere. How is your place. I am really happy to see your email and the support you are giving me for my successful project. I am excited to see your idea of building electrospinner and how they are being utilized now in the current world to make masks. Really nice to think of this. Yes cheap but effective.

I wanted to update you so many things since the past couple of weeks.

- My school is offering both in-person and virtual option for the year 2020-21. My mom opted for virtual option. In virtual option, the time expected will be similar to in-person school day and instructional engagement will be as in-person with assesment and grading practices in consistent those of in -person classroom. Most of my friends also opted for virtual option while few opted for in-person. Hope this year goes well and anything might change in middle. Hope in Florida also they are offering the similar way of options in schools.

- Couple of weeks before, I had virtual meeting with St.Louis Regional science fair coordinator. She is willing to help me with filling forms, getting approval, and other necessities for Honors competition. She is already helping 14 students from different schools and she included me in her list . Also as you keep mentioning each time, she told statistics is very important. And she will teach me when I collect all of my data as I am not exposed to T-tests.

- I started researching how to proceed with the continuation topics and I guess I am getting good hold of it. I will share my ideas with you and please help me to finalize those by the middle of next week. I wanted to start this ASAP since my project involves plant growth, and I really want to complete it before fall as I am planning to do real time project.

- Also I got opportunity to participate in ASU - Sustainability science fair competition. Deadline for this is August 16th of this year. Science fair coordinator asked me to submit my old project. But there is lot of writing and video making specific for this competition which I am working on it.
Please guide me for my clarifications and provide your suggestions. I will share with you as I complete. Also there is word limit for each topic and I am trying to modify.

- My mom arranged tutoring for ACT prep with Washu researcher which is my dream college. So getting busy with that too.


Thanks again for all your time.
Lakshita

Wow, Lakshita! You really are having a busy summer. I hope you find time to do some fun things--like shooting off fireworks. We had sort of a block party July 4 with people wearing red. white and blue masks and sitting in chairs a little further away than usual, but we did really enjoy it. We are all in this problem together and the more we can do to help others, the better.

I think most universities in Florida are going to open with some in-class lectures, and biology and chemistry courses that have labs are going to have to meet in person. Elementary, middle and high schools were planning to open until virus testing in FL showed the huge spike in cases after the reopening of some businesses. It's more worrisome now because younger people in their 20s are getting sick--not bad enough to go to hospital, but they could transmit the virus to grandparents.

You can add me to your home-schooling contact list. I'm glad your mom decided to play safe and go with virtual schooling. I would do the same in her place, at least until the risk has dropped way down.

I was glad to hear that you made contact with the scifair coordinators for St. Louis and ASU. They can really help you and guide you so that you don't waste time and get the most out of what you are doing.

I am happy to be a part of your team! All you have to do is call on me when you need advice on project design and experiments and help with writing good persuasive proposals.

Stay safe and stay happy,

Sybee

Hi Mr.Sybee,

Thanks for your valuable support. Sure I will post my clarifications this week.

That is really nice you had great July 4th. Yes I fired crackers on that day and my whole neighborhood was super bright as everyone were firing crackers and it was really nice to watch.

Hope in FL also they have the virtual option for schools . It is really scary. Even in India, it is spreading more and they have implemented lockdown in many places.

Stay safe and I will keep in touch.
Thanks,
Lakshita

Hi Lakshita,

Things seem to be improving a little in Florida. I hope more people are taking this seriously so we can get through this faster. Wearing a mask and staying home may be inconvenient, but it is way better than ending up in the ICU.

I am happy to be one of your virtual teachers, so whenever you have questions or want to float some ideas just let me know. Adversity begets creativity, and humans are very resourceful or we would not be here today. Use the web for educating yourself but make sure of the facts and beware of scams.

Best wishes to you and your family,

Sybee

Hi Mr.Sybee,

I completely agree with you on how the Covid 19 situation should be handled. I am also trying to stay home as much as possible, however I am forced to go outside for necessities.

I am really lucky to have you as my virtual guide.

I researched on my next project ideas. My next project is based on the attached PDF. I am planning on simulating real time agriculture using the orange and avocado peel mixture.

Let me try to understand what should be done step by step:

In the first sub experiment, I am trying to measure the average fold change of the water absorption capacity of orange & avocado peel mixture in distilled vs tap vs saline water.
I understood from the attached PDF (I just gave the part of the project - first part since I am not able to attach the original PDF here due to size limit) and by research that the absorption capacity of the SAP strongly depends on the dissolved salts that are present in the solvent: the higher the amount of salts, the lower the absorption capacity. This aspect is crucial for the success of SAP in agriculture-related applications. So I think a greater amount of SAP should be used in water with higher salt content.

As we have done in the previous year project, I am planning to use the below procedure (still not yet finalized—I will need your help for the final editing and write-up, this is just the basic idea)


 2 grams of orange & avocado peel mixture were placed into 3 individual graduated beakers.
 Distilled water was added to one of the three beakers until the SAP could no longer hold any more. For accuracy, after 15 minutes, any excess water was carefully pipetted off so as not to disturb the polymer. This was repeated for Tap water and Saline water individually.
 Each of the beakers of water swollen polymers was weighed and the fold change (final weight of the SAP /initial weight of the SAP) was recorded.
 The above steps were repeated for trials 2 and 3 and the readings were recorded.


Find below my clarifications:

1. Based on my research, I found:
1 liter of saline water – 9 grams of salt (0.9%)
1 liter of tap water – 0.05 grams of salt ()
1 liter of distilled water – 0 grams of salt

Please let me know if the above amount of salt is correct. I don’t know about percentage. Can you please help me with that.

2. Also, I’m not sure where to purchase the saline water.

3. My assumption of the results of the experiment is that saline water should be the least absorbed by the SAP and the distilled water should be the most absorbed.

4. In the attached PDF, she has also tested to evaluate the effect of the environmental electrical conductivity on the swelling properties of the SAP. Starting from the water-saturated condition, the desaturation of the SAP was then monitored for seven days by weighing the amount of water that was released daily. I think that would complicate the hypothesis and hence I am trying to stick with just testing the absorption capacity in different types of water as my first sub experiment.
Please let me know your suggestions and idea on this.


I am researching on the second sub experiment testing in different types of soil. I am planning to use Tomato plant this year. I really wanted to finish off the experiment before Nov.

Thanks for the help and your time.
Lakshita

Hi Lakshita,

I'm glad to hear you are staying safe and able to work from home. It would be a sad world without the internet. One of my next projects is to install some solar panels on the roof of the porch so I can generate my own electricity. Then I will save up enough to buy a Tesla battery to store the power for use at night and on cloudy days.

I read the paper on the cellulose SAP and it seems to be a useful source of info for your salinity experiment. My suggestion would be to use more different concentrations of NaCl than two. Farmers in some parts of the world have to use brackish water for irrigation and could also benefit by adding a SAP to the soil so they would not have to irrigate as often. Using a lot of chemical fertilizer can also increase the salt levels in soil.

I think what I am trying to tell you is that I think 0.9% NaCl is much higher than any irrigation water would ever be. That's why I think you need to do several lower concentrations. I know that 0.9% NaCl is used in hospitals as 'normal' saline for i.v. drips, but you need to test maybe 0.01%, 0.05%, 0.1%, etc., as being closer to the saline water that a farmer might actually use.

One problem that I saw from reading the paper and from looking at some other references was that salinity is measured as electrical conductivity--probably because this is much simpler than any other method. Converting conductivity to a percentage of salt (or salts, not just NaCl) is not so easy as far as I can tell.

Testing many NaCl concentrations with your SAP will give you better statistics also. You will be able to plot water capacity vs NaCl concentration and see the trend line more accurately. I have no idea how sensitive the orancado powder will be to salts, but that is something you will find out from the experiment. Try to make a large single batch of orancado so that you will be doing all the tests from the same batch. I expect that there is some variation from batch to batch, so it would be most accurate to use the same batch for all experiments.

Your second set of experiments with different types of soil sounds even more interesting. I have always made compost and added it to my garden soil because it is mostly sand and does not hold water. The organic matter in the compost acts as a kind of SAP to hold and release water longer. I would expect that the maximum benefit of orancado would come from adding it to sandy soils which are quite common in arid parts of the world. Soil that contains a lot of natural organic matter would not benefit as much because it already has a pretty good water-holding capacity.

Enough rambling for now. Let me know what you think about what I said about the salinity.

Keep in touch and stay safe,

Sybee

Hi Mr.Sybee,
Your new project is such a nice idea! Once you mentioned it, I feel interested to try that out once I have enough money as an adult. Please let me know how it goes.
I read your email and below are the changes I thought of. Please provide your suggestions and correct me.
1. As you mentioned, I am planning to experiment with the water used in real time cultivation.
- Surface water ( I am planning to collect water from Missouri river)
- Groundwater from wells
- Rain water
- Brackish water – I guess I can try asking Petco for Brackish water or get coralife salt from them and mix with regular water. Please suggest.
Hope the above types of water is good for comparision right or do you want me to compare distilled water, Tap water and saline water as well?

2. I researched on TDS meters that read electrical conductivity (EC), which is related to charged particles in the water (ions).

- I saw ‘3 In 1 TDS EC PPM Multifunctional Water Quality Meter Tester Pen LCD Display’
In walmart.

- TDS meter gives the reading in ppm. Hope we can use the same for the graph purpose right?

- More TDS means more EC right? Higher the TDS less water is absorbed. Is that correct?

- If I compare the above types of water for water absorption with SAP, then Rain water should absorb more followed by Groundwater, then surface water and then Brackish water. Correct me if I am wrong.

3. Please also let me know what would be my control variable for this sub experiment.

Thanks so much for your time. Based on your suggestions, I will start ordering materials for this sub experiment. Next week we are getting rain here so I can keep some buckets outside and collect rain water.

Thanks,
Lakshita

Hi Lakshita,

I'm glad to hear that you are making such good progress getting started on the project.

If you want to keep your experiment more realistic, you need to test water that has salt, but not too much. Brackish water has a little salt but is way less salty than sea water, which would kill plants if used for irrigation. That's why I suggested a range of NaCl concentrations from 0 to 1%.

1% is one part per 100, which is the same as 10,000 parts per million (ppm). Check the Walmart conductivity meter online and compare it to other meters. If you are going to buy a meter, you need to know if it will be sensitive enough to read the salt content of your solutions. And, yes, the more salt in the water, the better it conducts electricity. That is how the meter works. If you put the probe in distilled water, the reading should be zero.

Let's say the lowest NaCl concentration that you test is 0.01%. That is equivalent to 100 ppm. So, the meter has to be able to accurately read salt down to 100 ppm or below. I'm sure water testing can be more complicated but for now this should be enough. Remember that well water and river water will contain many different kinds of salts (technically, 'ions') and some like nitrate and phosphate and potassium are necessary for plant nutrition, so don't get the idea that all salts are bad. It's the same with humans. I'm suure you have heard that excess sodium (as in NaCl) in the diet is associated with higher risk of heart disease, but potassium (as in KCl) is OK.

I'm trying to teach you chemistry and physics as we go along, so please look up anything you don't understand online and ask questions. Now that in-class education is being replaced by virtual classrooms, it is becoming more your responsibility to self-educate. The internet is the greatest resource ever for self-educators, just try to make sure the source of information is reputable. Sites associated with known universities and companies are usually reliable. And, it is always good to go to a number of sites to compare. Just be careful of those that are advertising something, or want you to register with an email so they can solicit you with offers.

That's enough lecturing for now. Post again later.

Stay safe,
Sybee

Hi Mr.Sybee,

Thanks so much for your inputs. I did research based on your email and got what you are saying. Please find below my clarifications.

- If I understand correctly, you want me to compare water with different NaCl concentration (0-1%) and check for the water absorption capacity correct?

- I understand TDS meter checks for all the dissolved salts not specifically NaCl which are interested in. I also got higher the salinity levels will affect irrigation.
I found the following meter which checks the NaCl concentration in water in amazon. Can you please take a look and let me know if I can go ahead and use this.
eSeasonGear SALT-3050 Waterproof IP65 Meter, Digital Salinity PPM Temperature Tester for Salt Water Pool and Koi Fish Pond

- I was initially thinking to compare different types of water usually used in the agriculture like surface water/tap water/rain water and so on.

Please let me know your thoughts if I still can have the independent variable as types of water. Ofcourse I will be providing the salinity level in each type of water.
If you suggest me to use the types of water as independent variable , what types of water should I use.
I saw in the PDF experiment, she compared just distilled water vs Tap water which doesn't make sense. Please suggest on what types of water should I use?

- Since Brackish water will kill the plants, I guess we need not test with Brackish water right? Please let me know.

- what would be the control variable in this case. Should I take Distilled water as my control as it has no salts.

Thanks so much for your valuable time without which I would not have got this much of information.

Thanks,
Lakshita

Hi Lakshita,

Your description is absolutely correct, but you can still test tap water, rain, river water, lake water--whatever you have access to. Brackish water may be usable on some kinds of plants. It depends on how much salt it contains. Brackish is less salty than seawater but more salty than fresh, but I did not see an average ppm range. Water from wells along the coast of Florida sometimes turns brackish because of intrusion of salt water from the Gulf of Mexico. If it is only slight then the water is still usable.

Some plants are quite salt tolerant, and there is research being done now to try and insert the genes for salt tolerance into plants lacking salt tolerance so they could be grown in areas where the farmers have to use brackish water for irrigation.

I took a look at the salinity meter that you found on Amazon and I'm a little concerned about this statement in the description:
*** Works ONLY for Salt Water Pool and Koi Fish Pond Salt level testing.
*** Will NOT work for Sea/Marine/Salt Water Fish Tank Salt level testing *** Will NOT work for Food salt level testing! *** Will NOT work for any other application!

I don't understand how a meter that measures ppm NaCl could tell the difference between water from a Koi pond and water from a salt water fish tank, but it makes me a little suspicious, so I would look for a different meter. In the scientific literature, conductance is measured in a unit called siemens (named for the discoverer) abbreviated S. The conductance is given as S per meter and usually as milliS (one thousandth of an S) or microS (one millionth of an S) per meter. If you can find a meter that measures in these units and ppm, that does not cost more than $50, then it would be more useful. Otherwise just find one that measures ppm salt without the restrictions to Koi ponds (!?).

Yes, DW should be the control. The water types and salt solutions are the independent variables and water absorption by the SAP is the dependent variable. I guess your hypothesis would be: The greater the salinity the lower the water absorption. There would be a lower limit of detection I suspect where you would not be able to measure a difference. Rainwater can be quite pure and might give the same absorption as DW. Even tap water might be the same as DW unless you have a water purifier that exchanges mineral ions of sodium.

Let me know what you decide about the meter.

Best wishes,

Sybee

Hi Mr.Sybee,

Thanks for your time. This really helps.

- I was under the impression that the previous salinity meter does not work only in marine water/sea water as it reads only till 5000 ppm and salinity is more in marine waters. But when I did more research on that and with reviews, that meter doesn't seem to give accurate results.

I found another meter. I think this looks good. But you also please take a look and let me know if I can use this for measuring NaCl concentration. This product is also in Amazon.

Pen Type Salinity & Temp TDS Salt Checker Tester Meter ATC NaCl, 100 PPT / 9999 ppm / 10% / 0.95-1.08 SG Pond Pool Saltwater Aquarium Seawater Drinking Water Quality

- As you suggested I will take DW as my control. I am planning to compare NaCl concentration in Tap water/River water/Well water/Brackish water. Please suggest if this ok.

- Can you also please tell me where do I find Brackish water. Is there a way to get Brackish water from Petco?
If I go to Petco, I can convince my mom to get pet fish for me. I have no pets and siblings and so I am lonely

I am also started researching on my next sub experiment. Once I get hold of first sub experiment, I will post my clarifications for my second.

Thanks so much. Stay safe.
Lakshita

Hi Lakshita,

I checked the meter description on Amazon and it looks like it will do everything you need for your experiments. I suggested getting a conductance meter that reads in Siemens/meter, but I think those are all too expensive.

Brackish water has more salt than tap water but less than sea water. I don't think you can buy 'brackish' water, or that you need to because it is just water with a little salt added. There are towns along the west coast of Florida where so much fresh water has been pumped out of the aquifer that the salt water from the Gulf of Mexico is able to filter through the limestone and make the well water a little salty--brackish. Sometimes it is still drinkable, but other times not.

When you make the series of NaCl standards to test the meter, all these water samples will be brackish.

Let me know when you get the meter and try it. Do some more reading on salt water and crop plants. It is an interesting area for research and highly useful as much potential farmland is unusable because of salinity in the soil.

Stay well,

Sybee

Hi Mr.Sybee,

How are you doing. Today here it is thuderstorms, so I kept big vessel to store rain water for my project

Thanks for all your suggestions. From your email, I saw you mentioned about making series of NaCl standards. I am not planning to make salt concentrations for my project due to lack of lab facility, rather use different types of water and test NaCl concentration in those types using meter and mention the concentrations for my test results. My hypothesis for this sub-experiment would be "Higher NaCl concentration lesser is the absorption capacity". I will try finding Brackish water somewhere near by. Testing would be to compare Tap water vs Rain water vs River water vs Brackish water taking Distilled water as control.

If I am correct with my understanding, Rain water should be most absorbed, followed by Tap water , River water and Brackish water the least.

Please correct me if I m misunderstood with my research planning for this sub experiment.

I will start posting my second experiment questions from tomorrow.

Thanks and stay safe,
Lakshita

Hi Lakshita,

So, you got some rainwater for your experiment--great! Did you collect it directly? I wouldn't use what came out of a drain spout because it might have some dirt or salts in it.

You don't need a school lab to make some NaCl standards. These will be very useful for checking your meter and comparing with the conductivity results of your various water types. You have a digital scale that weighs in grams, don't you? Otherwise, you could just use the approximate weight of one teaspoon of table salt = 6 g. So, to make a 1% (10,000 ppm) NaCl solution, just dissolve 1 tsp of salt in 600 ml of DW. You can use a 4-cup measure with milliliter markings to measure 600 ml. To make 0.05% (5000 ppm) NaCl, dilute 50 ml of 1% with 50 ml of DW. To make 0.01% (1000 ppm) NaCl, add 1 tsp (~5 ml) of 1% NaCl to 500 ml DW. To make 0.001% (100 ppm) NaCl, add 1 tsp of 0.01% NaCl to 500 ml DW. And there you have it--NaCl standards from 0 to 1% in five concentrations. These NaCl solutions are all brackish, so you can choose the one that seems like it could be usable for irrigation, maybe 100 ppm.

Did you order the salt concentration meter? Let me know when you get it and try it to make sure it reads correctly.

Make a large batch of orancado SAP so you will have enough to use the same batch for all experiments (three runs for each test, at least).

Good luck!

Sybee

Hi Mr.Sybee,

Thanks so much for giving me details how to make concentrations. I will do as you suggested. Also I started preparing orange & Avocado SAP mixture. Yes I am making it in large quantity. I threw the last year's left over mixture . I didn't know I will end up doing the extension of the same project. Anyways I started preparing and first step completed. It is in the process of drying.

I tried to catch rain water directly in huge vessel. But only some got collected. Not sure why. We had hail storm yesterday and only little got collected. I will be trying to catch this whole week.

I haven't ordered the meter still. Will be doing this week. I will keep you posted.

Thanks for all your help. I will post my second sub-experiment questions tomorrow.

How is Florida. Here in St.Charles county the cases are increasing and got mail from school that they may take decision based on health department whether to open or close for this semester. I am really missing my school and wish this pandemic should end soon.

Stay safe
Thanks,
Lakshita

Hi Mr.Sybee,

I am attaching herewith the rest of the project (second and third steps) where she is testing with different types of soil. I am starting to research based on her ideas and will post my clarifications. Please go over the document and let me know how you suggest we can proceed with the next experiment. I am planning to go with just tomato plant.

Thanks,
Lakshita

Hi Lakshita,

I hope you and your family are well.

I took a look at the experimental protocol you sent and it has a lot of variables--plant species, soil type, depth of placement of SAP and watering regimen, etc.. Which variables are you planning to test with tomato plants?

I found a number of problems with the experimental description. How was the SAP prepared and stored? Where did the soil come from? Was it sterilized? Why is the pH so high (>8.0)? Tomato plants do poorly in alkaline soil. What was the temperature? Was supplemental light used in the greenhouse?

In my opinion, it would have been statistically better to test fewer variables and use more samples per test to get more accurate results.

Let me know your plans and attach your methods section so I can check it. Are you planning on starting the project soon?

Sybee