Evaluating Landscape and Local Drivers of Pollination in Melittophilous Tallgrass Prairie Forbs: Effects of Surrounding Land-use on Pollen Limitation of Chamaecrista fasciculata & Prescribed Burning on Flowering and Pollination of Dalea purpurea

Abstract

Tallgrass prairies are one of the most endangered ecosystems in North America. Habitat loss and degradation of remaining prairies threaten both the biodiversity and functioning of these ecosystems. At the landscape scale, loss and fragmentation of existing prairie may limit regional pools of species and abundance of individuals, hampering movement of plants and animals between suitable habitats. At the local scale, degradation of prairies has been exacerbated by loss of native grazers and suppression of fire, the major ecological forces that historically shaped prairie species and communities. While the impacts of these factors on biodiversity in prairies is well-established, little is known about the role of these factors on plant-pollinator interactions, an important ecological process for many prairie forbs. As restoration of prairie habitats is one of the chief means of protecting prairie habitats and biodiversity, evaluating the roles of these factors in mediating ecological processes such as pollination will be critical to their reconstruction. Within this thesis, I explore how two important aspects of habitat restoration management, landscape context and prescribed burning, influence pollination in two common, widespread prairie forbs reliant on insects, namely bees, for pollination. The findings of these studies serve as initial assessments of two under-explored topics with relevance to tallgrass prairie conservation: how placement of a restoration effects recruitment of pollinators and the pollination they provision a habitat, and how animal-mediated pollination influences prescribed burning’s effects on plant reproduction.