Biodiversity, Disturbance, and Resilience: Evaluating the Role of Biodiversity in Moderating Ecosystem Response to Interacting Disturbances

Biodiversity contributes to ecological resilience (resilient systems are those that maintain, through internal processes and feedbacks, their essential structure and function when disturbed), yet experimental evidence of the relationship between resilience and biodiversity in large–scale field settings is sparse.

Goals

By systematically introducing multiple disturbances to research units established within large restoration plots, aims to bridge the gap between tightly controlled mesocosm experiments and uncontrolled observational studies linking biodiversity and ecosystem functioning.

Current Status

During the summers of 2015 and 2016, research was conducted on a tallgrass prairie restoration owned and maintained by the Nature Conservancy of Nebraska. Disturbances were introduced to both low– and high– diversity plots in the form of rain interception (simulating drought), biomass harvesting (to simulate haying), nitrogen additions (representing nitrogen runoff from agricultural use), and paired biomass removal/nitrogen additions.

 Pre–disturbance sampling from 2015 revealed a strong gradient in soil organic matter and associated differences in plant communities, rates of invasion, and soil microbial activity. This gradient illustrates one reason for researching biodiversity and resilience in situ; by studying how natural environmental heterogeneity influences ecosystem responses to added disturbances, we can develop a more nuanced understanding of the magnitude of the role of biodiversity in maintaining system resilience, and when the benefits of biodiversity may be more or less pronounced than suggested by more tightly controlled greenhouse experiments.

 In 2016, post–disturbance data was collected for several soil and plant community characteristics in order to quantify the responses of each experimental unit to our added disturbances, and a second round of disturbances added. This study is expected to continue through 2017, with results presented to a thesis committee in the summer of 2017.

Rain shelter in field
Rain shelter in field
Inside view of a rainout shelter in the field (courtesy Becca Bevans)
Inside view of a rainout shelter in the field (courtesy Becca Bevans)
Principal Investigator(s)
-Craig R. Allen, NE CFWRU
Graduate Student(s)
-Rebecca Bevans, M.S.
Project Duration
May 2015 - July 2017
Funding
-UNL Institute for Agriculture and Natural Resources
-The Nature Conservancy
Project Location
Nebraska Platte River Prairies Restoration