plant competition for nutrients in a phosphorus-limited ...€¦ · plant competition for nutrients...
TRANSCRIPT
Plant competition for nutrients in a phosphorus-limited tundra ecosystem
Emily Pickering PedersenJoseph Gaudard, Bo Elberling, Anders Michelsen
ITEX meeting 2019, Parma, Italy
Temperature
Arctic tundra ecosystems
Belowground changes
Plants
Temperature
Arctic tundra ecosystems
Belowground changes
Plants
Increased decomposition →
Increased nutrient availability
Plant species community
Ecosystem functions
Temperature
Arctic tundra ecosystems
Belowground changes
Plants
Increased decomposition →
Increased nutrient availability
Plant species community
Ecosystem functions
OrganicN
Nutrient availability and uptake
Nutrient availability and uptake
Abiotic factors↓
Precipitation
Bintanja & Andry, 2017
Nutrient availability and uptake
Geology↓
P-limitation
Bintanja & Andry, 2017
Abiotic factors↓
Precipitation
Nutrient availability and uptake
Geology↓
P-limitation
Microorganisms
Biotic interactions↓
Competition
Bintanja & Andry, 2017
Abiotic factors↓
Precipitation
Nutrient availability and uptake
1. Does increased summer precipitation alter plant N uptake?
2. Does P-limitation restrict plant N uptake?
3. What are the patterns of plant-plant and plant-microbe competition for nutrients?
Precipitation P-limitation Competition
Field location
Disko Island, Greenland69°14’ N 53°32’ W
Experimental design
PH2O
• Full factorial design• 8 mm precipitation/week• 10 g P/m2 (growing season)
Experimental design
PH2O
• Full factorial design• 8 mm precipitation/week• 10 g P/m2 (growing season)
Amino acid(glycine)
13C15N(0-10 cm depth)
Microbes
Plants
Ecosystem
Data Slides Removed
Conclusions
1. Increased precipitation reduces plant N uptake → plant stress
Conclusions
1. Increased precipitation reduces plant N uptake → plant stress
2. P accumulates, but limitation effects are unclear
Conclusions
1. Increased precipitation reduces plant N uptake → plant stress
2. P accumulates, but limitation effects are unclear
3. Plant-plant and plant-microbe competition is apparent → species community change
Thank you