Biomes in a BoxBiomes in a BoxRainforest vs. Grassland vs. Desert – Who will win?Rainforest vs. Grassland vs. Desert – Who will win?

Our project was how rainforest, desert, and grassland biomes affect different organisms such as worms and grasses.The first thing we did was research the soil composition of the three biomes. Then we constructed our biomes. We added worms, embryos and grass seeds to each biome box. We observed and recorded the growth of the grass for several weeks. We then deconstructed our biomes and observed the differences of the soil, grass, worms, and embryos.We found out that some soils make the grass

grow differently. Several of the worms died during the process of this project. Our data indicated that by changing the amount of water added to the B boxes, RB and GB did the best because they received the most water, and DB did the worst because it had the least amount of water. Our A boxes tested for the effect on grass and worms by soil composition. Our findings were that RA grass grew the best and had living worms and hatched embryos.In conclusion soil composition and water affects the way that

organisms interact within their environment.

Mrs. Shields 6th grade classLincoln Elementary School

Stockton, California

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Rainforest Grass GrowthBiomes Grass Growth

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Grassland Grass GrowthDesert Grass Growth

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IntroductiIntroductionon

Rainforest:•RB grass was almost always taller than RA. RA and RB showed us a drop in growth rate at the same time, but RB’s drop was the greatest.•RA and GB had worm embryos hatch. RB and RA had adult worms that survived.

From our results we are able to conclude that the type of soil and the amount of soil moisture has a lot to do with the growth rate of our seeds. Our original idea was that grassland would grow the most, but based on our findings DA’s grass grew the best. We believe this is because there is more sand. We still want to know why this is so. When we changed the amount of water that was added to the B boxes we originally thought that RB and GB would do the best because they received the most water and DB would do the worst because it had the least amount of water. Our findings support this belief. We also did a soil analysis to help us understand what was happening in the soil, but the results were inconclusive. This is something we would like to research. Of the thirty-six embryos that were inserted in the boxes only three hatched. We are not sure whether this was a result of soil, moisture, faulty embryos, or temperature or we just weren’t able to find them. Also most of our worms died. The deaths could have been a result of any of the above factors.

Procedures -Collected all the materials. -Figure the composition of the different types of soil.-Put the soil amounts into the boxes.-Mixed the soil.-Put 2 earthworms into the soil.-Spread 1/4 cup grass in each box.-Put 6 embryos down one side of each box.-All the “A” boxes got 30 squirts of water . DB got 20 squirts of water. RB got 60 squirts of water , and GB got 50 squirts of water.

-Observed daily-Recorded grass growth rate.-Tested the soil for pH, P, K, N-Empty boxes and searched for worms, embryos, and made soil observations.

Soil Composition

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Rainforest Grassland Desert

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–We chose to do this project because we were learning about biomes, and we wanted to know what would happen if we put grass and worms in the biomes. We chose to do the Desert (D), the Rainforest (R), and the Grassland (G) biomes, because we were interested in seeing what the differences would be. The Rainforest was the wettest biome, the desert was very dry and very little grew, and the Grassland was in the middle.– We took differently composed soil samples and put them in a 19-liter clear container. In the Desert boxes we had more sand than other biomes because we researched that the desert has more sand than organic matter and clay/silt combined. The grassland had the same percentages of all the soil components. The rainforest had a small amount of organic matter and was mostly composed of silt and clay.-We learned that all of the biomes have some type of grass. We decided to use grass as a plant in each biome to watch how the soil and watering effected them. To keep the grass alive we added water to whatever biome it was supposed to go to. All the “A” boxes got 30 squirts of water, all the “B” boxes got water depending on the type of biome. Rainforest got the most water followed by the grasslands, and lastly the desert. We put in lots of different grasses, 68% ryegrass, 10% bluegrass, 10% red fescue, 10% chewings fescue (2% of inert material).We put earthworm embryos in our boxes to complete the biomes.

Grassland:GA and GB grass both started at approximately 1.1cm and ended at about 9cm. GB had a steady growth pattern, whereas GA had some ups and downs.

•Desert:• DA grass grew taller at a steadier rate then DB. DB had lots of ups and downs. On January 21 DB grew grater than DA.

The three biomes compared do not show a significant difference in growth:GA had denser grass when compared to the others. It also was the most affected by the 2 small droughts that the boxes experienced. DA had the steadiest growth rate with the least amounts of ups and downs. RA began well, but dropped at the very end.