ARTHROPOD FOOD WEBS IN ARCTIC TUNDRA: TROPHIC INTERACTIONS AND RESPONSES TO GLOBAL CHANGE

• Main Author: Asmus, Ashley Lila
• Other Authors: Gough, Laura
• Format: Thesis
• Language: English
• Published: 2017
• Subjects: Food web; Communities; Arthropods; Trophic structure; Intraguild predation; Wolf spiders; Insects; Herbivory; Nutrient addition; Arctic; Tundra
• Online Access: http://hdl.handle.net/10106/26956

Arctic ecosystems are undergoing rapid change. Terrestrial arctic arthropods (insects, spiders and others) are not only appreciably diverse, but also sensitive to their environment. As such, tundra arthropod communities and food webs could provide critical insight into the ecological consequences of global change in the Arctic. My dissertation explores the underpinnings of arthropod community and food web dynamics in arctic tundra. First, I explore how changes to plant production and plant community composition affect arthropod community composition, trophic structure and food web function. I also explored one key trophic interaction: cannibalism among wolf spiders, the most abundant terrestrial predator in most arctic systems. Last, I examine the effects of plant communities and weather on arthropod phenology and activity, key determinants of the rate and role of arthropod-mediated food web processes like predation, decomposition and pollination. Overall, my research reveals that arctic consumers are strongly limited not only by their resources, but also by cold temperatures in the Arctic. Early springs, warmer temperatures, increased plant production and greater shrub dominance – key consequences of arctic global change–will affect the composition of arthropod communities and the ecological functions they perform.