PmP612s Lecture Notes - Carduus Nutans, Species Description, Superadditivity
Document Summary
The purpose of this study is to determine the effects invasive species would have for the purpose. To determine the effects of superadditive, additive, or subadditive invaders, three experiments using a response-surface design during the plant species life cycles was implemented. The researcher"s hypothesis of a stronger competitive effect of carduus nutans was not supported by the results. The results found no notable response towards competition between conspecifics vs. congeners and weak response both species had on combined density. The study concludes from the results that it would be better to focus efforts on unaffected areas because invaded areas will feel a marginal effect by newer invaders. The collection of each species data may not be completely correct. In the methods subheading of species description, the author admits to the difficulty of differentiating the species apart at the seedling and rosette stages. On top of this he writes that they both occupy similar habitats, primarily in pastures and roadsides.
