Author
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De Queiroz, Tara |
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Submitted to: Arctic and Alpine Research
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 4/15/2009 Publication Date: 8/10/2009 Citation: Forbis, T.A. 2009. Negative Associations Between Seedlings and Adult Plants In Two Alpine Plant Communities. Arctic, Antarctic and Alpine Research. 41(3):301-308. Interpretive Summary: Plant species’ requirements at seed and seedling stages are critical in determining their distributions. Proximity to adult plants, as well as the presence of litter or rocks on the soil surface can influence seedling success. By comparing the microsite characteristics of points occupied by naturally occurring seedlings to the characteristics of unoccupied points in fellfield and dry, moist, and wet meadow alpine plant communities on Niwot Ridge, Colorado, U.S.A., this study addresses the following questions: Are seedlings more likely to be near an adult plant or in litter than are unoccupied points? Does the proximity of seedlings to adult plants vary among communities? In the fellfield community, are seedlings more likely to be located next to a rock than are unoccupied points? I found that seedlings were farther from adult plants than were unoccupied points in the wet meadow, a community with dense vegetation cover and wet soils. Contrary to expectation, I also found that seedlings were farther from adult plants than were unoccupied points in the fellfield, the driest, most barren community. Seedlings were not more likely than unoccupied points to be located in areas of litter buildup, and fellfield seedlings did not occur disproportionately within the protection of a rock. This study suggests that competition between adult plants and seedlings may be taking place both in highly productive and in very unproductive alpine plant communities. Technical Abstract: Plant species’ requirements at seed and seedling stages are critical in determining their distributions. Proximity to adult plants, as well as the presence of litter or rocks on the soil surface can influence seedling success. By comparing the microsite characteristics of points occupied by naturally occurring seedlings to the characteristics of unoccupied points in fellfield and dry, moist, and wet meadow alpine plant communities on Niwot Ridge, Colorado, U.S.A., this study addresses the following questions: Are seedlings more likely to be near an adult plant or in litter than are unoccupied points? Does the proximity of seedlings to adult plants vary among communities? In the fellfield community, are seedlings more likely to be located next to a rock than are unoccupied points? I found that seedlings were farther from adult plants than were unoccupied points in the wet meadow, a community with dense vegetation cover and wet soils. Contrary to expectation, I also found that seedlings were farther from adult plants than were unoccupied points in the fellfield, the driest, most barren community. Seedlings were not more likely than unoccupied points to be located in areas of litter buildup, and fellfield seedlings did not occur disproportionately within the protection of a rock. This study suggests that competition between adult plants and seedlings may be taking place both in highly productive and in very unproductive alpine plant communities. |
