Poster

         Ecology

Floral and pollinator trait variation in high-elevation meadows of the Madrean Sky Islands

Presenting Author
Liliana Benitez
Description
In the face of shifting global biodiversity patterns, it has become increasingly critical to recognize that ecosystem function is not only mediated by species-level diversity, but also by interactions between species. Mutualistic interactions, such as those between plants and their pollinators, seed-dispersers, and mycorrhizal associates, play a critical role in ecosystem function. Previous research has shown that greater species-level diversity in partner trophic levels enhances plant reproductive success, gene flow, and nutrient cycling. This is believed to be driven by species’ functional trait diversity, however, it is understudied in the context of mutualistic interactions. Furthermore, complementary traits between interacting partners, known as trait matching, have been proposed as an additional mechanism governing ecosystem function, particularly for functions that rely on interspecific partnerships. Over the period of 3 years, we collected floral and bee trait data at 25 independent and approximately 3 ha-sized meadows across the Madrean Sky Islands system, an iconic region consisting of over 30 isolated mountain tops with high-elevation meadows. We additionally obtained climate and soil data for the region from the PRISM climate group database and the U.S. Forest Service Terrestrial Ecological Unit Inventory geodatabase. We aim to evaluate whether ecologically similar patches contain plant and pollinator communities with similar trait spaces. Preliminary results also show that our sites exhibit substantial variation in trait diversity (e.g. mean tongue lengths range from 1.06mm - 4.27mm, mean corolla tube lengths range from 3.6mm - 13.2mm), and trait matching (e.g., site regression coefficients for tongue and corolla lengths range from 0.03-0.98, with a value of 1 representing full trait matching). Climate conditions also varied considerably across sites and years. For instance, total July precipitation during the start of the monsoon season ranged from 83 mm to 249 mm in 2017, 79mm to 183 mm in 2018, and 66 mm to 236 mm in 2021. Our ongoing work will assess the impact of trait composition on pollination network metrics within the same study sites.