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The effects of Intraspecific competition in Trifolium repens L. Brian Roberts Student Education Department Tennessee Tech University Cookeville, Tennessee 38505
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Introduction Do plants compete for resources? Do plants compete for resources? Does this competition affect growth or survival? Does this competition affect growth or survival? It is important to understand how organisms interact with each other. It is important to understand how organisms interact with each other. Organisms interact in a variety of ways, some of which may be harmful. One of these interactions is called competition, in which individuals compete for resources such as food, nutrients, water, light, and so on. Organisms interact in a variety of ways, some of which may be harmful. One of these interactions is called competition, in which individuals compete for resources such as food, nutrients, water, light, and so on. Intraspecific competition is when individuals compete only with members of the same species. Intraspecific competition is defined as the relative reduction of germling growth and survival in high- density cultures compared with low-density cultures (Steen 2003). Intraspecific competition is when individuals compete only with members of the same species. Intraspecific competition is defined as the relative reduction of germling growth and survival in high- density cultures compared with low-density cultures (Steen 2003).
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Introduction Because plants are sessile after they germinate, local conditions around individual plants, including the densities and sizes of neighboring plants, have a crucial influence on growth and survival (Suzuki et al. 2003). Because plants are sessile after they germinate, local conditions around individual plants, including the densities and sizes of neighboring plants, have a crucial influence on growth and survival (Suzuki et al. 2003). Three general effects of intraspecific competition have been identified for plants growing in dense stands (Yoda et al. 1963). Stands with higher densities generally have reduced sizes, reduced survival probabilities, and changes in size-distribution. Three general effects of intraspecific competition have been identified for plants growing in dense stands (Yoda et al. 1963). Stands with higher densities generally have reduced sizes, reduced survival probabilities, and changes in size-distribution. The experiment was done to determine the effects of intraspecific competition in Trifolium repens L. (white clover) on survival and growth. The experiment was done to determine the effects of intraspecific competition in Trifolium repens L. (white clover) on survival and growth.
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Introduction Intraspecific competition was tested by planting clover in different densities and then measuring variables (growth rate, survival, average plant mass, ect...) over a five week span. Intraspecific competition was tested by planting clover in different densities and then measuring variables (growth rate, survival, average plant mass, ect...) over a five week span. I expected that the plants grown in larger densities would display a lower survival rate and would exhibit growth differences. I expected that the plants grown in larger densities would display a lower survival rate and would exhibit growth differences. The experiment was expected to disprove the null hypothesis, which states the clovers’ growth and survival will not be affected by intraspecific competition. The experiment was expected to disprove the null hypothesis, which states the clovers’ growth and survival will not be affected by intraspecific competition.
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Objective/Hypothesis Statement Objective Statement Objective Statement To determine the effects of intraspecific competition in Trifolium repens L. on survival and growth. To determine the effects of intraspecific competition in Trifolium repens L. on survival and growth. Null Hypothesis Null Hypothesis Intraspecific competition will not have an effect on the survival or growth of Trifolium repens L. Intraspecific competition will not have an effect on the survival or growth of Trifolium repens L.
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Methods and Materials The methods and statistical approach used in this experiment were taken from a lab manual (Brown 2004). The only variation to the original experiment is the deletion of some of the variables measured. The methods and statistical approach used in this experiment were taken from a lab manual (Brown 2004). The only variation to the original experiment is the deletion of some of the variables measured. We took pots and filled each with soil up to within 1 cm of the top of the pot. We took pots and filled each with soil up to within 1 cm of the top of the pot. Then, we planted different density sets of clover in each of the pots. The densities were: 3, 5, 10, 18, 34, and 68 seeds in their respective pots. Then, we planted different density sets of clover in each of the pots. The densities were: 3, 5, 10, 18, 34, and 68 seeds in their respective pots. We thinned the pots to 2, 4, 8, 16, 32, or 64 plants after germination. We thinned the pots to 2, 4, 8, 16, 32, or 64 plants after germination.
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Methods and Materials Over a 5 week period, we provided water and sunlight for the plants and made the following measurements: growth rates, survivorship, average plant mass, and stem mass per plant. Over a 5 week period, we provided water and sunlight for the plants and made the following measurements: growth rates, survivorship, average plant mass, and stem mass per plant. Data Analysis: Data Analysis: We used t-tests to compare mean plant weight, mean stem weight, and mean growth rate for the different densities. We used t-tests to compare mean plant weight, mean stem weight, and mean growth rate for the different densities.
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Results
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Discussion In chart 2 the mean plant weight shows a slight decrease as density increases. In chart 2 the mean plant weight shows a slight decrease as density increases. This may be an effect of intraspecific competition although the t-test results show there is not enough significant evidence to reject the null hypothesis involving mean plant weight for any of the densities. This may be an effect of intraspecific competition although the t-test results show there is not enough significant evidence to reject the null hypothesis involving mean plant weight for any of the densities.
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Results
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Discussion Chart 3 illustrates the result of intraspecific competition on mean stem weight is a decrease in mean stem weight as density increases. Chart 3 illustrates the result of intraspecific competition on mean stem weight is a decrease in mean stem weight as density increases. Again, the t-tests show there is not enough evidence to reject the null hypothesis in all of the densities Again, the t-tests show there is not enough evidence to reject the null hypothesis in all of the densities
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Results
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Discussion Chart 6 compares mean growth rate with density. Chart 6 compares mean growth rate with density. Again, we see a slight decrease in the variable (mean growth rate) as density increases. Again, we see a slight decrease in the variable (mean growth rate) as density increases. But again, the t-test results are nonsignificant and fail to reject the null hypothesis in all of the densities. But again, the t-test results are nonsignificant and fail to reject the null hypothesis in all of the densities. Therefore, intraspecific competition does not affect the mean growth rate of our clover plants. Therefore, intraspecific competition does not affect the mean growth rate of our clover plants.
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Results
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Discussion In chart 7, the number of plants originally planted is compared to the number of plants surviving. In chart 7, the number of plants originally planted is compared to the number of plants surviving. The chart illustrates an increase in the number of plants surviving as the density of original plants planted increases. The chart illustrates an increase in the number of plants surviving as the density of original plants planted increases. However, the percentage of plants surviving reduces by almost half from the lowest density (100%) to the highest density (53%). However, the percentage of plants surviving reduces by almost half from the lowest density (100%) to the highest density (53%). The densities and the percentage of plants surviving are as follows; 2:100%, 4:91%, 8:81%, 16:80%, 32:79%, and 64:53%. The densities and the percentage of plants surviving are as follows; 2:100%, 4:91%, 8:81%, 16:80%, 32:79%, and 64:53%. So, the percentage of plants surviving decreases as the density increases, which could be due to intraspecific competition. So, the percentage of plants surviving decreases as the density increases, which could be due to intraspecific competition.
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Conclusion Overall, the results fail to reject the null hypothesis in the interspecific experiment, which states intraspecific competition will not effect the survival and growth of the clover plants. Overall, the results fail to reject the null hypothesis in the interspecific experiment, which states intraspecific competition will not effect the survival and growth of the clover plants. Although the effects differ for different variables, none were strong enough to be significant according to the t- tests. Although the effects differ for different variables, none were strong enough to be significant according to the t- tests. The results disagree with the research done in support of the effects of intraspecific competition by Yoda, Steen, and others mentioned previously. The results disagree with the research done in support of the effects of intraspecific competition by Yoda, Steen, and others mentioned previously.
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