Natural history of Shortgrass Prairie Plant Species at the Pueblo Chemical Depot 2018-2019

  • Cody Allyn Back Colorado State University-Pueblo
Keywords: Shortgrass prairie, Plant biodiversity, Floristic provinces, Drought, Perennials, Annuals, Undisturbed


Undisturbed shortgrass prairie is a rich, diverse ecosystem that is becoming endangered due to disturbance by humans in the Midwest. We surveyed the effects of droughts and heavy precipitation years to analyze the plant composition on an undisturbed shortgrass prairie ecosystem located on the Pueblo Chemical Depot. We found that during drought years, there are few species of plants capable of growing, all plants were perennials, and there were few invasive species of plants. When comparing the floral compositions between a wet year and a dry year we found that wet years have higher diversity, more invasive species, more annual plants, and that most drought-year plants were not found again during the wet year. Our results demonstrate that drought years select for native perennial plants, wet years create more possibilities for annuals and invasive plants, and drought-year plants are most likely outcompeted by other plants during wet years.


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Natural Sciences