2022 Early Hearing Detection & Intervention Virtual Conference

March 13 - 15, 2022

<< BACK TO AGENDA

5/21/2019 | 2:15 PM - 2:30 PM | INTERACTIVE EFFECTS OF TEMPERATURE AND NITROGEN AVAILABILITY ON PRIMARY AND SECONDARY PRODUCERS | 253 AB

INTERACTIVE EFFECTS OF TEMPERATURE AND NITROGEN AVAILABILITY ON PRIMARY AND SECONDARY PRODUCERS

Altered temperature and nutrient regimes are important global drivers of ecological change. While each of these drivers has been intensively studied independently, less is known about how food webs and ecosystem processes respond to their interactive effects. We examined how four Icelandic streams, representing a gradient of mean annual temperatures (8°C-15°C), responded to whole-stream nitrogen (N) enrichment. We expected differences in community structure, basal resource availability, and metabolic rates across the thermal gradient, and thus divergent responses to N enrichment. Specifically, we predicted that: 1) N enrichment would alter primary producer community composition by reducing the abundance of non-palatable N2-fixing cyanobacteria in warm streams, and 2) increased production of palatable algae would enhance secondary production in warm, N-rich streams. Under ambient nutrient conditions, primary production increased with temperature, but biomass of palatable algae decreased by 47%. Following N enrichment, primary production was amplified across the thermal gradient, while biomass of palatable algae increased by 79%. We predict that these changes to the resource base will cascade to secondary producers, propagating the interactive effects of temperature and N enrichment to multiple properties of food web structure and dynamics.

Secondary Production
Food Webs
Temperature

Presentation:
This presentation has not yet been uploaded.

Handouts:
Handout is not Available

Transcripts:
CART transcripts are NOT YET available, but will be posted shortly after the conference

Presenters/Authors

Kate Henderson (), Montana State University, kahenderson121@gmail.com;