Thursday, March 12, 2009

Lake Core Investigation

By Molly, Nicole, Taylor and Robert

Question: How do diatoms differ from 50 cm to 70 cm?

Data: We did about 5 different slides at 50 cm and also at 70 cm. The diatoms differed between the two observations.


Claim: Both were the same size but they were shaped differently. The diatoms at 50 cm were shaped like bricks and the diatoms at 70 cm were shaped like ladders.

Evidence: There were more diatoms at 70 cm than 50 cm.

Reasoning: At 50 cm we didn't see many diatoms, but at 70 cm we saw more than 20 diatoms

Further Questions:

1. Would've our results changed if we went deeper than 70 cm?

2. Would the moisture or dryness of the soil change the amount of diatoms?

Lake Adley Diatom Count

By: Ellen D. & Brittany M.

Question: If we look at 2 different cores at the same depth would there the same kinds of diatoms.

Procedure: First we will clean off a slide, then take a small sample of core A at 20cm from the top. Then we will mix it with a drop of water and place a slide cover on top. We will then place it under a compound microscope and find as many diatoms as possible. We will then repeat these steps two more times. After recording our data we will take another slide sample, but this time from core B but still at 20Cm from the top. We will then look for more diatoms. Then we will repeat these steps 2 more times. After recording our data we will compare the types of diatoms we found.

Variable changed: cores
Variable measured: kinds of diatoms
Controls: Depth, amount of sediment

Core A
Slide 1: Anomoeoneis, Navicula/Pinnularia, Aulacoseira, Cymbella
Slide 2:Aulacoseira, Cyclotella, Hantzchia/Nitzschia, Surirella
Slide 3:Cyclotella, Navicula/Pinnularia, Aulacoseria

Core B
Slide 1:NONE
Slide 2:NONE
Slide 3:NONE

Conclusion: We conclude that there is a big difference in the 2 different cores. We came to the this conclusion because in the first core we saw many different types of diatoms, but when we looked at the next core we did not find any. We think this is a logical conclusion because there might have been more diatoms in one spot in none in the other

Friday, March 6, 2009

lake core sample

We did oberservations on the lake core sample of adley.
Our question:How many diatoms are there at 2cm than
Data:first day of the observations we found 1 diatoms under 2cm.
and under 10cm we found 3 diatoms.
the secound day of observations we found 2 diatoms under 2cm.
and under 10cm we found 3 diatoms.
the third day of observations we found 2 diatoms under 2 cm.
and under 10cm we found 2 diatoms.
conclusion: The concluison to our lake core sample is the more the
lake core sample goes in the ground the more diatoms appeat on the
slides , when we look at 2cm we found f diatoms over all and when we
did 10cm we found 8 diatoms over all.
further questions: 1) can we find more diatoms at 50cm than 10cm?
2)when you look at 10cm for diatoms and go 10cm down each time how
many ditaoms will you find
BY: Mark Hewitt and Justin Thomas

mackenzie, shelby, and alex

Question: How many different diatoms are there at 10 cm down and 60cm down?

Variables change: depth
Variables measure: how many different diatoms
Controls: same core, same materials

lake core
compoud scope
tooth picks
slip cover
note book

1 clean slide
2 get sample from 10cm down and put on slide
3 put water on and spread
4 examine under a compound scope
5 repeat #1 and get a sample from 60cm down
6 repeat #3 and #4
7 record data in note book
8 when finished, clean slide and put stuff away

Slide #1 at 10cm down
asterionella tormosa-1
Slide #2 at 10cm down
Slide #3 at 10cm down
Slide #1 at 60cm down
Slide #2 at 60cm down
Slide #3 at 60cm down
fragilaria capucina-3

claim-at 10cm down we found 6 different kinds of diatoms and at 60cm down we found 9 different kinds of diatoms.
evidence-we made three slides from each depth and examined them from under the compound scope. of all the slides we took from 10 cm down we found five synedra, one asterionella formosa, ten melosiera, one amphora, one cyclotella, and one planothidium/achnanthes. of all the slides at 60cm down we found one epithemia, nine navicula/pinnularia, two cyclotella,14 melosiera, two gyrosigma, one rhopalodia, one synedra, three amphora, and three fragilaria capucina.
reason-we think there are more at 60cm down because it's older and maybe there were more diatoms at that time. it may have been at the end of the drought period so maybe the habitat would have been different. and we have a lot of benthic and they hangout towards the bottom of the lake. we believe that this was also before lake adley became polluted.

Diatom Investigation

Question: Are there different diatoms at 10 cm and at 90 cm?
By: Becky, Brianna, Hunter, and Jason

Procedure:Take a sample of the lake core from 10cm. Make a smear slide by putting the dirt on and adding some water. Put the smear slide under a compound microscope and record what diatoms we see in our notebook. Repeat these same steps 2 times. Take a sample of the lake core from 90 cm. Make a smear slide by putting the dirt on and adding a few drops of water. Put the smear slide under a compound microscope and record what diatoms we see in our notebook. Repeat 2 times.


  • toothpick

  • compound microscope

  • slide

  • slipcover

  • lake core


At 10 cm:

  • 2 Fragilaria Capucina

  • 2 Synedra

  • 2 pieces of Gyrosigma

  • 2 pieces of Asterionella Formosa

  • 1 Navicula/Pinnularia

At 90 cm:

  • 4 pieces of Asterionella Formosa

  • 3 Fragilaria Capucina

  • 7 synedra

  • 2 pieces of Gyrosigma

Claim/Evidence: We found out that there are different kinds of diatoms at 90 cm and at 10cm. At 90 cm there were 4 pieces of Asterionella formosa, there were also 3 Fragilaria Capucina, 7 synedra and 2 pieces of Gyrosigma. At 10 cm we found 2 fragilaria capucina, 2 Synedra, 2 pieces of Gyrosigma, 2 pieces of Asterionella Formosa and 1 Navicula/Pinnularia.

Reasoning: Maybe we incorrectly evaluated which diatoms were what. Maybe one of those areas of time were drier so only certain kinds of diatoms were able to survive. It could have been wetter one year so there were different diatoms.

Further Questions: What different kinds of pollen are there at different depths? When the sediment is larger are there more or less diatoms?

lake core investigation

zach sax, zach Question: What depth are the most diatoms found at. 10cm or at 80cm. Claim: we found more diatoms at 80cm. there were less diatoms at 10cm

Data: 80cm=16

Reasoning: The sediment that is deeper is older. Which gives more time to collect at the bottom.

Further question: how many more diotoms are at 20cm then 70cm
: what diatoms will you find the most

Thursday, March 5, 2009

Diatoms in the Lake Adley core sample

By Trent, Connor, Tyler and Dominic

Question: How many different kinds of diatoms are at 4cm and at 24cm?

1 take 2 samples one from 4 cm deep and one from 24 cm

2 put the samples on seprate glass slides

3 compare slides on a microscope

4 write down comparisins and differences between the diatoms on the slides

Variable Changed: Depth

Variables Measured: Number of Diatoms

Controls: Number of samples taken


With many slides at the correct depth of 4cm and 24cm our results were we did not find any diatoms at 4 cm at 24cm we found several cymbella and synedra for this maybe as the depth increases your diatoms may increase. Because they live on the bottom you will find more than the ones that float.

Wednesday, March 4, 2009

Osakis Diatom Study

Olivia, Avery, Taylor, Tyler

Question: Are there more Diatoms at two cm or at 80 cm?

I. Clean off slide
II.  Put two drops of water on the slide
III. Take one toothpick and put it in the mud about one-half cm
IV. Take it out
V. Take a circular motion to spread the mud around
VI. Look under a microscope
VII. Count all the Diatoms that can be identified

I. Slide
II. Toothpick
III. Cover Slide
IV. Microscope
V. Mud
VI. Water
VII. Water Dropper
VIII.  Notebook/Paper

Two cm deep five different Diatoms- 4 slides, types are: Melosira, Nitzchia, Diatoma, Stephanadiscus, and Cocconeis
Eighty cm deep six different Diatoms- 4 slides, types are: Cymbella, Melosira, Frustulia, Nitzchia, Surirella, Euontia 

Claim: Eighty cm deep had one more Diatoms that two cm.
Evidence: We took four slides of each and found that there was just one 
more Diatoms at two cm than at eighty cm.
Reasoning: The reasoning we came up with was that eighty cm could've 
settled so that they could've cross bred to make a different Diatom or they just be different conditions the farther they go.

Questions/Comments: Very interesting shape description in the experiment by Nick, Dylan, Eric, RC

Osakis Earth Science Investigations

Lake Core Investigation, Osakis High School

Names: Paul, Rachelle, Becka, John

Procedure: 1. Drop two drops of water on glass slide.
2. Smear the sample onto the slide with tooth picks.
3. Put the cover slip on.
4. Examine the samples under a microscope.

Materials: 1. Glass slides
2. Cover slips
3. Compound microscope
4. Pencils.
5. Science journal
6. Tooth picks
7. Water dropper
8. Core sample (at 1cm and 33cm).
Data/Result: Total Diatoms-166

Conclusion: We found that there are more diatoms at 33 cm that at 1 cm.  Three out of four of our people had more diatoms in 33 cm than in 1 cm.  We think that there are more diatoms at 33 cm because it had more time to develop. 

Do only certain diatoms live during a certain time or doesn't it matter when or where they lived.

Tuesday, March 3, 2009

Osakis Earth Science Investigations

Students from Osakis High School will soon be publishing their research from the Lake Adley sediment cores collected last February.  Eighth graders will be reporting their counts of diatoms at two separate depths of the 90 centimeter core sample.  

Friday, February 27, 2009

Diatom Investigations


Are there more dirrerent kinds of diatoms in the core A at 60 cm. than in core B at 5cm?


1. Make a smear slide from the 1st core at 60cm.
2. Look at the slide under a microscope.
3. Make another slide from the 2nd core at 5cm.
4. Repeat step two.
5.Compare the results


Slides, toothpicks, lake core, microscope, pencils, notebook


Core A 4 kinds 60cm. two slides
Core B no kinds 5cm 4 slides


Claim: Core A had more dirrerent kinds of diatoms thatn core B.

Evidence: We took two slides from core A and four slides from core B and core B still didnt have any diatoms. We found four kinds of diatoms in core A and no kinds in core B.

Reosoning: The reason we didnt find any diatoms in core B may be because when we took the sample in core B it was at 5cm. and thats younger than core B at 60cm and core B had more time to produce because the fact that it is older, and core B at 5cm. has not had as much as a chance to form diatoms as core A did because its younger at 5cm.

2 Further Questions: What would happen to the number of diatoms if we moved the sample to 5cm. in core A, and move the sample in core B to 15cm. extead of 5cm.?

What core has the most diatoms at 20cm. in core A and B?

Nick Mace, Danny Aldrich, Ty Honkala, Theo Jahnke

Lake Core Investigation

Hi our names are Amelia, Brittany, Jessica, and Madison. We are from Parkers Prairie High School. We are doing an investigation on diatoms in 8th grade Earth Science. For this investigation we are using a core sample 90 cm deep in Lake Adley.

Question: How many different kinds of diatoms are found at 30 and 90 cm from the surface of the core.

Variables Changed: Depth sample was taken at.
Variables Measured: Kinds of diatoms.
Controls: Core, amount of sediment taken for slide, and procedure.


  1. First we will take a core sample with a toothpick from 30 cm deep.
  2. Put sample on slide and add a drop of water, then put a cover slip on top.
  3. Then view the slide under a compound microscope and look for kinds of diatoms. (mark this in notebook.
  4. Take the same steps at 90 cm deep.


  • core/core sample
  • toothpick
  • slide
  • cover slip
  • compound microscope
  • water
  • diatom sheet
  • pipette


Diatoms found at 30 cm deep

  • Navicula/Pinnularia
  • Fragellaria
  • Cymbella
  • Aulacoseira
  • Amphora
  • Cyclotella

Diatoms found at 90 cm deep

  • Cyclotella
  • Asterionella
  • Hantzchia/Nitzchia
  • Melosiera
  • Navicula/Pinnularia
  • Synedra


Claim: There are mostly different diatoms at 30 and 90 cm, but some are the same. We found about the same number of different diatoms at each site.

Evidence: We found 7 kinds of diatoms at 30 cm. They are the following. Navicula/Pinnularia, Cyclotella, Aulacoseira, Cymbella, Amphora, Asterionella, & Fragellaria. At 90 cm we found Navicula/Pinnularia, Hantzchia,Nitzschia, Cyclotella, Melosiera, Synedra, & Asterionella. We found three diatoms consisting in both sites. They were Cyclotella, Asterionella, & Navicula/Pinnularia.

Reasoning: We believe that the reason we found three of the same diatoms at both sites is because those three diatoms can live in multiple environments. The reason there are different ones found at 30 and not 90 cm could be because the water environment was different when 90 cm was the top of the lake bottom.

Further Questions

1) How long ago was 90 cm deep on the core the surface.?

2) How are different diatoms formed?

Wednesday, February 25, 2009

Lake Core Investigation

Hello, our names are Ally, Dana, Courtney, and Derek, we are in earth science and we are studying lake cores about diatoms.

Question: How many diatoms are there at 60cm compared to 10cm?

Variable Measured- How many diatoms.
Variable Changed- The sample at 60cm compared to 10cm.
1. Get the cores out and materials ready.
2. Get sample at 60cm, and put on a slide
3. Look at the sample under the microscope and count the diatoms.
4. Wash the one sample off.
5. Get sample at 10cm and put it on a slide.
6. Count the diatoms and record data.
7. Wash that slide off and do all the data.
8. Repeat the steps at each spot 4 times and count the diatoms from each one and record data.

- 8 slides
- Core sample (at 60cm and 10cm)
-8 slide covers
-8 tooth picks
-Water dropper

Sample 1- At 10cm we found 3 diatoms, and at 60cm we found 2 diatoms
Sample 2- At 10cm we found 4 diatoms, and at 60cm we found 5 diatoms
Sample 3- At 10cm we found 2 diatoms, and at 60cm we found 2 diatoms
Sample 4- At 10cm we found 5 diatoms, and at 60cm we found 2 diatoms
Total- At 10cm there were 14 diatoms total and at 60cm we found 11 diatoms total!


Claim- we found that there are more diatoms at 10 cm then at 60 cm. there were 14 diatoms at at 10 cm an 11 diatoms at 60 cm.

Evidence- We took 4 samples at both 10 and 60 cm. The first sample at 10 cm had 3 diatoms the 2nd one had 4 diatoms, the 3rd one had 2 diatoms and the 4th one had 5 diatoms. totaling 14 diatoms. Our 4 samples at 60 cm at 2 diatoms on the first slide, 5 diatoms on the 2nd one, 2 diatoms on the 3rd one and 2 diatoms on the 4th one, all totaling 11 diatoms.

Reasoning- This may be becuase at 60cm it was older because it was closer to the bottom, so there would be older and less diatoms then there would be at 10 cm, because the soil at 10 cm is newer and closer to the top.

Further Questions-
1. Would the amount of diatoms differ if we took samples at 20 and 70 rather then 10 and 60 cm?
2. If we used 2 different core samples and took samples at 10 cm and 60 cm would the amount of diatomns differ between the two cores?

Tuesday, February 24, 2009

Lake Core Investigation

Hello, our names are Nick, Dylan, Eric, and RC. We are doing an investigation on Lake Core Sediments.This is our investigation!

Question: Does the size of a sediment change wirh the core depth of 70cm to 90cm?

Slide Cover Piece
Copound Microscope
Lake Core Samples

1.Gather up all of our materials or supplies
2.Put a tiny bit of the lake sample on slide from 70cm
3.Put 1 drop of water on slide
4.Put slide cover piece over sample
5.Put slide under compound microscope
6.Find sediment size
7.Repeat steps 2-6 but take sample from 90cm
8.Compare sizes of sediment
9.Write down what we see

Variables Changed:We tooks samples from 70cm and 90cm

Variables Measured: Sediment Sizes


We use the same materials

We did the same procedure

Same core sample

And how much we sampled


At 70cm we found out:

Slide 1: smallish shape, long, ovalis, clear, dark specks scattered

Slide 2: slightly bigger, more ovalish, alot of dark specks, less clear, clear spotlight

Slide 3: bigger then slides 1 and 2, less roundish, clear on 1 side, lot of specks, lines coming off of it

Slide 4: same size as #2, very ovalish, lots of specks, clear in center, 1 corner missing

At 90cm we found out:

Slide 1: very large, clear stripes, lots of dark specks, a pointed bottom, flat top

Slide 2: 1/2 size as 1st, egg shape, less clear, lots of specks, 2 bigger specks, another sediments close to it.

Slide 3: slightly smaller than 1st, clear spots on edge, lots of dark specks, design looks like finger print, green lines on it, turtle shape

Slide 4: Same size as 2nd, it has a turdish shape, has a point on the top and the bottom was round, 1 large darks spot, lots of sediments surronding it


We found out that at 90cm there are larger and less clear. Another thing is that in the 70cm mark almost all of the sediments were ovalish and at the 90cm they were a lot bigger and more of a wierd shape, such as eggish, coneish, and one even looked like a dog turd!!! we know it was dryer at 90 than at 70 because the sediments were larger at 90 than at 70. We know this because when it is dryer the sediments stick together than get blown into the lake. But when it is wet out and constantly raining the sediments stay apart from each other and get drained into the lakes when they are smaller.

2 Further Questions:

1. Are ther different types of diatoms at different depths?

2. Does the climate effect how long a diatom lives? If so how?

diatom study

Hi, our names are Alec, Mitchell, Brendon, and Shawn. And we are studying diatoms.

QUESTION: Are there more diatoms at 10cm. than at 70cm.

our procedure is 1. Walk over to the core. 2. Take tooth pick out of bag. 3. Take sample on slide. 4. Put sample on slide. 5. Put a drop of water on sample. 6. Smear sample and add coverslip. 7. Repeat three times at 10 cm and three times at 70 cm.8. Compare slides.

Variables: Change Depth
Variabled Measured: number of diatoms
Controls: same core, same amount at dirt

Conclusion: We found out that there where more diotoms at 70cm compared to 10cm. At 70cm there where 105 diatoms on three slides at 10cm there where 29 diatoms on three slides. at 70cm the time period could have been when they dumped sewage in the lake making more fertalizer for the plants and make more habitat for the diatoms.

2 Further Questions: 1. Does tempature effect the nubmer of diatoms? 2. Does the depth of water effect the number of diatoms?

Monday, February 23, 2009

Hi our names are LaDeanna, Brenna, Cole, and Dakotah. we were assigned to do a investigation on a sample core. this is our investigation!

Question: What is the difference in sediment size at 10cm compared to 90cm?

Procedure: 1. First we will take a sample from the core at 10cm. 2. Then we will create a slide for the 10cm sample. 3. Next we will take a sample fromt he core at 90cm. 4. Then we will create a slide for the 90cm. sample. 5. After, we will compare the two sediment samples under a microscope. 6. Finally, we will record our data in our notebook.

Materials: 1 spatula, 2 toothpicks, 2 slides, 2 coverslides, 1 microscopes.

Variable changed: 10 cm to 90 cm

Variable Measured: Sediment size

Controlls: same magnification, same size samples, same depths in core.


  • Sediments in 10cm are more clear than the 90 cm sediments.
  • Sediments at 90 cm are larger than sediments at 10 cm.
  • loosly formed ovals at the 10 cm & 90 cm measurements
  • sediments at 10cm are 2 times larger than the size of the pointer
  • sediments at the 90cm are 4 times larger than the size of the pointer


Claim-the 90cm sample we took has larger sediment than the sediments at 10cm

Evidence- the sediments in the 90cm sample were about 4 times the size of the pointer. The sediments in the 1ocm sample were only 2 times the size of the pointer.

Reasoning- We think that climate could determine the size of the sediments. We think so because when it's wet, sediments break off each other into smaller pieces, but when it's drier, they stay in one large sediment clump. So when it's dry, your going to have the larger clumps blow in because the smaller ones won't wash in due to lack of rain.

Futher Questions:

1. would the sediments sizes change, if we took our samples by the highway versus by a forest?

2. If the core was taken during the wetter season, would the sediments at 90cm have been smaller?

Friday, January 16, 2009

Diatom Investigation Results

Hi, My name is Anna! I am in 11th grade and for Earth Systems my teacher had me do an investigation with diatoms.

Question: What is the difference in species of diatoms in the different layers?

Materials: Core sample, toothpicks, microscope, glass slide, pencil, notebook, meter stick, cover slips, permanant marker, water, eye dropper

Procedure: 1. Take the core sample out of the wrapping. 2. Use the toothpick to scrape some of the sample up. 3. Spread what you have on the toothpick over the glass slide. So it is coated but not to thick. 4. Put one drop of water and place a cover slip over it. 5. Mark sample with the marker at 5 cm. 6. Put the slide under the microscope and see what you find. 7. Write down and see what you find in your data table. 8. Repeat steps 2-7 for 45cm, 95cm too.


Types of Diatoms Found:

5 cm-Tabellaria, Navicula, Cocconeis, Meridon, Pinnularia

45 cm - Tabellaria, Cocconies, Fragellaria, Surirella, Melosira, Diatoma

95 cm - Tabellaria, Surirella


I found out that from all three layers where I took samples, there was only one diatom that was in all of them. It was the Tabellaria diatom which is in the Pennales class. Other than that the layers had very different species of diatoms.

In 5 cm, I found Tabellaria, Navicula, Cocconeis, Meridon and Pinnularia. In 45 cm, I found some of the same ones which were Tabellaria and Cocconeis. The different ones I found were Fragellaria, Surirella, Melosira and Diatoma. In 95 cm, there were not any different species. It had Tabellaria, which was found in 5 cm and 45 cm, and Surirella, which was found in 45 cm. The reasons I think my data turned out the way it did is because I just used wet slide samples and I didn't use any chemicals to remove dirt. I think this is shy at 95 cm I did not find many diatoms. I also think I did not make the layer of sediment on the slide thin enough.

Further Questions:

1. How does a new species of diatoms come about?

2. What kind of story do amounts of diatoms tell?