Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
This Land is My Land, A Study of Intraspecific Competition Among Marigolds (Tagetes patula) K. D. Farley Undergraduate Student Environmental Biology Tennessee Tech University Cookeville, TN 38505 A Summary ?The Question? How do plants effect each other in high population density areas? -Objectives- To observe and measure how population density effects; The number of matured seeds (survival rate) Plant stem, leaf, and root size and wieght -Hypothesis- Population density will have no significant effect on plant community growth. A Summary -The Plan- Planting different size communities in identical areas, with the only variable being population density, measure size and weight after three to four weeks. !Don’t Tell Me, I Know! (Expected Results) The greater the density, the more competition will exist for sustenance, hence the less the struggling plant will grow more. Introduction I have noticed that flowers that are planted close together are often of smaller size than the same kind of plant planted solitarily. Experiments have shown that, between competing species, a plant that needs less nutrients to survive will exclude and live longer and healthier than its competitor (Dybzinski 2007). Introduction Studies have also concluded that community size can affect the outcome of certain species in competitive exclusion (Fletcher 2005). Although these studies take in consideration population densities among different species, how do plants react in dense populations among their own kind. Introduction It has also been claimed that plants competing for nutrients have sacrificed reproduction for root mass (Hutchings 2007). But would the plants sacrifice stem and leaf growth for their root size? Objective The objective of this experiment is to observe and measure how population density effects the number of matured seeds (survival rate) as well as plant stem, leaf, and root size and weight. Hypothesis Hypothesis – Plants in high population areas will grow less than the plants in less crowded areas Null hypothesis - Population density will have no significant effect on plant community growth. Population Density – number of plants in per volume of soil with limited nutrients and light. Community Growth – average growth of the plant population (weight, leaf number, blooms, root mass, etc.). Methods/Materials Materials Eight identical flowering pots (4in by 4in plastic pots) Marigold seeds Potting soil Ruler Measuring cup Heat lamp (regular light if heating lamp cannot be found) Methods/Materials Methods Plant four different population densities in four different pots. The first pot should have 1 seed, the second pot should have 4 seeds, the third pot should have 8 seeds, and the fourth pot should have 16 seeds. Simply follow the potting instructions on the seed container. Repeat previous step for another test group if desired. Once the seeds are potted, give each pot the same amount of water and sunlight. It is crucial that the only variable among the different pots is the number of seeds in each pot. After allowing the plants to grow for several weeks it will be time measure and collect the data. Keep track of which pot each plant came from. Carefully measure the length of the stem, number of leaves, number of blooms (pedals), weight of the leaves, of the stems, and of the root systems. Expected Results/ Benefits The more densely populated the environment the less an individual plant will grow. Once an understanding of growth effecting density is obtained, then applications could be developed for use in the agriculture industry. Timeline 9/03/2007 purchase materials 9/05/2007 set up project 9/12/2007-10/17/2007 carry out experiment 10/17/2007 collect results and raw data Timeline Budget Item Cost Amount Total Seeds $0.97p/bag 1 $0.97 Pots Stolen 8 $0.00 Water Free As needed $0.00 Labor $1,000,000.00 p/hr 12 $12,000,000.00 Works Cited Dybzinski, R., and D. Tilman. 2007. Resource Use Patterns Long-Term Outcomes of Plant Competition for Nutrients and Light. American Naturalist 170: 305-318. Fletcher, R. J. Jr., and J. L. Orrock. 2005. Changes in Community Size Affect the Outcome of Competition. The American Naturalist 166: 107111. Gudelj, I., and C. R. MacLean. 2006. Resource Competition and Social Conflict in Experimental Populations of Yeast. Nature 441: 498-501. Hutchings, M. J., M. Semchenko, and E. A. John. 2007. Challenging the Tragedy of the Commons in Root Competition: Confounding Effects of Neighbor Presence and Substrate Volume. Journal of Ecology 95: 252-260. Tilman, D. 2007. Resource Competition and Plant Traits: a Response to Craine et al. 2005. journal of Ecology 95: 231-234. ?Questions?