Response diversity: elucidating the long sought-after mechanisms underpinning ecosystem stability

Research Project

Project/Area Number	22K21332
Research Category	Grant-in-Aid for Research Activity Start-up
Allocation Type	Multi-year Fund
Review Section	1101:Environmental analyses and evaluation, environmental conservation measure and related fields
Research Institution	Okinawa Institute of Science and Technology Graduate University
Principal Investigator	ROSS Samuel 沖縄科学技術大学院大学, 統合群集生態学ユニット, ポストドクトラルスカラー (60961795)
Project Period (FY)	2022-08-31 – 2024-03-31
Project Status	Granted (Fiscal Year 2022)
Budget Amount *help	¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000) Fiscal Year 2023: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000) Fiscal Year 2022: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
Keywords	ecology / stability / response diversity / resilience / duckweed
Outline of Research at the Start	I will conduct 3 experiments on floating plants. 1: a simple test asking does response diversity produce less variable biomass. 2: an extension to different dimensions of stability (resistance, resilience etc.). 3: an extension to spatially-linked communities where dispersal/competition are possible
Outline of Annual Research Achievements	The JSPS Kakenhi Grant-in-aid for Research Start-up award has allowed me to begin research on my topic of response diversity. I have thus far bought many of the necessary equipment for my upcoming experiment (commencing June 2023) and have hired a research assistant to help with the experiment. Specifically, I have purchased 75 large plastic buckets, which will act as "mesocosms" for floating plant communities, as well as the necessary chemicals to keep the plants alive and to add Nitrogen stress. I will soon purchase a camera lens to keep daily photographs to measure plant growth, and will collect the plants locally to begin the experiment next month. My goal is to experimentally manipulate the number of plant species in each mesocosm and the amount of nitrogen plants are exposed to. Together, this will allow me to test whether the range of growth rates among species (that is, the response diversity of those plants to Nitrogen) affects their temporal variability (stability), which is a vital parameter for ensuring consistent ecosystem functioning.
Current Status of Research Progress	Current Status of Research Progress 2: Research has progressed on the whole more than it was originally planned. Reason I am currently following my planned timeline, and now have the necessary equipment to conduct several follow-up experiments after the initial experiment.
Strategy for Future Research Activity	I will conduct an experiment this summer (May-August) using floating aquatic plants in large 100L mesocosms. The goal of this experiment is to ask whether response diversity can drive the stability of floating plant communities despite Nitrogen addition. After successful completion of this experiment, I will write up the results for publication and present them at academic conferences. Next year, I intend to conduct another follow-up experiment with the equipment already purchased for this year's experiment. The follow-up experiment will dive deeper into the mechanisms shaping stability by manipulating environmental conditions (e.g. Nitrogen or temperature) with different periodicities, such that I will produce multiple pulse disturbances with different frequencies and intensities. This will allow me to stretch our understanding of the link between response diversity and stability in a range of ecologically realistic environmental conditions.