Tuesday, November 23, 2010

October 24, 2010: Grasslands. Kathryn and Kate.

Figure 1.  Our transect on Nose Hill.  Photo by KS.
One foggy morning in September, we had to get up early to go to school. We weren’t too excited about having to walk all the way to Nose Hill Park, and so as we walked along we were trying to think of a research question. We decided that for the sake of it we were going to research how abiotic factors affect biotic factors in the grasslands. We thought it was going to be a really boring project, but instead it turned out to be pretty fascinating.
The first thing we saw when we got to Nose Hill was grass everywhere. We put our tools down and began climbing up the hill to build a transect, shown in Figure 1. That was when we realized that there wasn’t just boring grass everywhere like we originally thought, but also bushes and thistles and some beautiful flowers. Looking closer, we could see the diversity of species among the grasses and other plants, and we started collecting samples of them.
After cutting down plants for testing biomass, we hammered a soil corer into the dirt and pulled out samples of soil from the top and the bottom of our transect. While collecting soil, we found a caterpillar and a worm, and we decided to take the caterpillar back to the lab. Finally, we were allowed to leave the cold hill and go back into the school right in time for lunch, which was good because we were very hungry by then.
Figure 2.  Springtail.  Photo by KS.
Over the next couple weeks at school, we dried out our plants so we could measure biomass and classify the different species, and we also tested our soil to find bugs. After getting extremely frustrated with the research we had to do, we were able to find quite a lot of information on our plant and insect species that helped us answer our research question.
Under the microscope, we found a tiny insect (Figure 2) in the soil sample we took at the top of the hill. It had a fork-like tail called a furcula and this helped us identify it as a Springtail, most likely from the family Isotomidae. The springtail is an arthropod, an invertebrate with a hard exoskeleton and jointed legs. Springtails live in humid, colder climates, so it wasn’t that surprising that we were able to find it in the top layer of the soil because it was a cold day; the temperature at ground level on the top of the hill was only 9.6˚C, not taking into account the frosty wind that was blowing around the hills at the time. Calgary in general is a very dry area, but the springtail has a special organ called the collarphore which scientists think helps it to absorb moisture from the soil in order to maintain their need for humid conditions. This would be an adaptation to abiotic factors in the Nose Hill environment that allows it to live there.
As for plants, we found that the majority of our plants were able to grow in both shade and sun, and also grew best in fairly well-drained soils. Where they grew on the hill depended on how much sun they needed. Along the top of the hill grew pasture sage and asters that need to be exposed to full sunlight, whereas Wood’s rose grew in a sheltered nook farther down the hill where it could be in partial shade.  Because the hill was very steep, we knew that the soil would drain well because water would easily make its way down the hill, both on the surface and underground. One of the more common grasses we found was called brome. It was able to grow all over the hill, which is because it has a massive root system. Since its roots wind deeply into the soil, they act as both an anchor for the grass against the strong winds and supply it with water from belowground, as well as helping control soil erosion of the hills.
We didn’t think that this was enough evidence to answer our question, so then we went to Edworthy Park to take more samples and do more research. The transect at Edworthy (Figure 3) was very flat, so it was a slightly different environment than Nose Hill, but it was still a grassland area.
Figure 3.  Our transect at Edworthy Park.  Phhoto by KB.
In the soil samples from Edworthy, we found more springtails. At the area we had taken soil samples from, there was lots of moss and fungi and decomposing matter; springtails are decomposers and feed on fungi and decaying vegetation. We also found a soil mite from the family Orbatidae. The mites also eat fungi and in fact live in very similar conditions as springtails. They are usually found in the top layer of the soil, which at Edworthy was covered with decomposing leaves and plants.
            There were also a lot of grasses at Edworthy and a large amount of thistles, but no shrubs. According to our research, all of the species we were able to identify grew in full sun, which made sense since there were no large bushes or trees nearby our transect area to create shade. Since the land was so flat, there wouldn’t be much opportunity for water to gather in it, and so it made sense to read that both goldenrod and prairie sage were highly drought tolerant. Since grasses made up the majority of the plants at Edworthy, their large root systems would allow them to access water far below the ground. This would explain why other plants wouldn’t grow there, as their roots would not be long enough to reach as deep as the grasses.
            After doing all this research, we found that species definitely adapt to the abiotic factors in their environments in order to survive. Whether it be a bug changing its diet to the food sources available or a plant developing long roots to reach water supplies, all species must conform to the limitations of their environments.

Resources (Listed in order of information used)

Meyer, John. (2009) Collembola: Springtail. Retrieved Oct. 18, 2010 from the Internet: http://www.cals.ncsu.edu/course/ent425/library/compendium/collembola.html
Buginfo.com. (2010) Springtails. Retrieved Oct. 17, 2010 from the Internet: http://buginfo.com/article.cfm?id=94
Murray, Tom. (2007) Isotomidae springtails. Retrieved Oct. 17, 2010 from the Internet: http://www.pbase.com/tmurray74/springtails_family_isotomidae
Bowes, Garry, and Peat, Heather. (2005) Management of Pasture Sage. Retrieved Oct. 12, 2010, from the Internet: http://www.agriculture.gov.sk.ca/Management_of_Pasture_Sage
Ray, Crystal. (2006) Planting, Growing, and Caring for Asters. Retrieved Oct. 12, 2010, from the Internet: http://www.associatedcontent.com/article/32311/planting_growing_and_caring_for_asters.html?cat=32
GardenGuides. Wood’s Rose (Woodsii) and Smooth Brome (Inermis). Retrieved Oct. 11, 2010, from the Internet: http://www.gardenguides.com/taxonomy/woods-rose-rosa-woodsii/ and http://www.gardenguides.com/taxonomy/smooth-brome-bromus-inermis/
VanDyk, John. (1999) Lowa Insect Information Notes: Springtails. Retrieved Oct. 17, 2010 from the Internet: http://www.ipm.iastate.edu/ipm/iiin/sprinta.html
Minor, Maria. (2004) Soil Mites and Other Animals. Retrieved Oct. 18, 2010 from the Internet: http://www.massey.ac.nz/~maminor/mites.html
England, Angela. (2008) Plant Profile Goldenrod (Solidago). Retrieved Oct. 16, 2010 from the Internet: http://www.suite101.com/content/plant-profile-goldenrod-solidago-a72562
University of Texas Wildflower Center. (2010) Artemisia ludoviciana: Asteraceae (Aster family). Retrieved Oct. 16, 2010 from the Internet: http://www.wildflower.org/plants/result.php?id_plant=arlu

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