Collaborators: Anna Duke, Ahlora Gartland, Darby Ford, Chinonso Ejere
Abstract: In this lab, seven samples of leaf litter and one sample of soil was collected. They then sat under a light for a week, drying out so the critters could be collected. Then, the amount of diversity in the samples was recorded. The leaves definitely had more diversity than the soil. However, they weren’t incredibly diverse. Many of the species found in the leaf litter were mites. The Simpson’s Index number was .79, therefore the Index of Diversity was .21 and the Reciprocal Index was 1.27.
Problem: How does the biodiversity in leaf litter compare to soil?
Hypothesis: The biodiversity of leaf litter will be higher than the biodiversity of soil.
Control Group- Soil
Experimental Group- Leaf litter
Independent Variable- Leaf and soil samples
Dependent Variable- Number of invertebrates
Materials-
· Dissecting microscope
· Berless funnel
· Leaf litter
· Alcohol
· Source of light
· Soil
Methods:
· Collect samples of leaf litter from the woods, and one soil sample
· Put the samples above a Berless funnel
· Put a light over top the samples, and wait for the light and heat from the light dry them out
· Have a cup at the bottom with alcohol for the critters to fall in once they die
Data:
Abstract: In this lab, seven samples of leaf litter and one sample of soil was collected. They then sat under a light for a week, drying out so the critters could be collected. Then, the amount of diversity in the samples was recorded. The leaves definitely had more diversity than the soil. However, they weren’t incredibly diverse. Many of the species found in the leaf litter were mites. The Simpson’s Index number was .79, therefore the Index of Diversity was .21 and the Reciprocal Index was 1.27.
Problem: How does the biodiversity in leaf litter compare to soil?
Hypothesis: The biodiversity of leaf litter will be higher than the biodiversity of soil.
Control Group- Soil
Experimental Group- Leaf litter
Independent Variable- Leaf and soil samples
Dependent Variable- Number of invertebrates
Materials-
· Dissecting microscope
· Berless funnel
· Leaf litter
· Alcohol
· Source of light
· Soil
Methods:
· Collect samples of leaf litter from the woods, and one soil sample
· Put the samples above a Berless funnel
· Put a light over top the samples, and wait for the light and heat from the light dry them out
· Have a cup at the bottom with alcohol for the critters to fall in once they die
Data:
Simpson’s Index: .79
Simpson’s Index of Diversity: .21
Simpson’s Reciprocal Index: 1.27
Simpson’s Index of Diversity: .21
Simpson’s Reciprocal Index: 1.27
Data Analysis: This data shows that the leaf litter is more diverse than the soil. However, the leaf litter isn’t very diverse itself. Most of the critters found in the leaf litter were mites. The Simpson’s Index is .79, meaning the Index of Diversity is .21. This means that if a random critter is pulled from the sample, there would be an 80% chance of it being a mite. The soil, however had one protura and one mite. Those were the only critters found in the soil. Also, these index’s show that the leaf litter in which they live in is not very rich or even. The richer the area, the more diversity. Since there isn’t a lot of diversity here, the area isn’t very rich.
Conclusions: This lab concluded the hypothesis to be true- The leaf litter is more diverse than the soil. It also gives the problem a clear answer. There could be several reasons why the organisms move away from the light and down the funnel. They could be nocturnal, and aren’t used to seeing light. Also, if they are used to living in cold and damp areas, then the light is hot and it dries things out. Because of this, they’re trying to stay away because they don’t want to get dried out. The biodiversity of the leaf litter in this lab appears to be low density. Since mites are the vast majority of the critters found, it’s likely that if you randomly pull out a critter, that it’ll be a mite. Also, the Simpson’s Index of Diversity of these results is .21. This shows that it has a low diversity.
If an environmental scientist was researching or studying biodiversity, he or she would need to take more than one sample, because different areas could have different diversities. For example, in the same forest, a wet and soggy area under a tree is going to have a different diversity than a drier area that gets more sunlight. If the scientist wanted to measure the diversity of the entire forest, he would need to take many different samples of the areas where diversity can differ, and then calculate the Simpson’s Index.
In Scientific American, they discuss the different types of critters found in leaf litter. Most of the critters found are invertebrates. They help the ecosystem because they feed on the leaf litter and break it up. Bacteria and fungi can help decompose the litter by converting it to chemicals that benefit the plants. Therefore, they are decomposers which is one of the most important things to have in an ecosystem. Leaf litter is a good place for some critters to hibernate, or to make their nests. Some spend their whole life in there, and some come and go depending on the season or time of year.
Citation:
Lin, Kevin, and CityScience. "Seasonal Science: What Lurks in the Leaf Litter?" Scientific American Global RSS. N.p., 18 Oct. 2012. Web. 05 Mar. 2014. <http://www.scientificamerican.com/article/bring-science-home-leaf-litter-biodiversity/>.
Conclusions: This lab concluded the hypothesis to be true- The leaf litter is more diverse than the soil. It also gives the problem a clear answer. There could be several reasons why the organisms move away from the light and down the funnel. They could be nocturnal, and aren’t used to seeing light. Also, if they are used to living in cold and damp areas, then the light is hot and it dries things out. Because of this, they’re trying to stay away because they don’t want to get dried out. The biodiversity of the leaf litter in this lab appears to be low density. Since mites are the vast majority of the critters found, it’s likely that if you randomly pull out a critter, that it’ll be a mite. Also, the Simpson’s Index of Diversity of these results is .21. This shows that it has a low diversity.
If an environmental scientist was researching or studying biodiversity, he or she would need to take more than one sample, because different areas could have different diversities. For example, in the same forest, a wet and soggy area under a tree is going to have a different diversity than a drier area that gets more sunlight. If the scientist wanted to measure the diversity of the entire forest, he would need to take many different samples of the areas where diversity can differ, and then calculate the Simpson’s Index.
In Scientific American, they discuss the different types of critters found in leaf litter. Most of the critters found are invertebrates. They help the ecosystem because they feed on the leaf litter and break it up. Bacteria and fungi can help decompose the litter by converting it to chemicals that benefit the plants. Therefore, they are decomposers which is one of the most important things to have in an ecosystem. Leaf litter is a good place for some critters to hibernate, or to make their nests. Some spend their whole life in there, and some come and go depending on the season or time of year.
Citation:
Lin, Kevin, and CityScience. "Seasonal Science: What Lurks in the Leaf Litter?" Scientific American Global RSS. N.p., 18 Oct. 2012. Web. 05 Mar. 2014. <http://www.scientificamerican.com/article/bring-science-home-leaf-litter-biodiversity/>.