poplar trees field in kurdistan region of iraq.pptx
MELNHE overview 2016
1. 3 sites:
•Jeffers Brook
•HBEF
•BEF
2 stands per site:
1 mid-age
1 mature
9 stands at BEF:
3 young
3 mid-age
3 mature
Multiple Element Limitation in Northern Hardwood Ecosystems
2.
3. Five Years with MELNHE: What have we learned?
LIMITATION
Foliar N:P is in the colimitation range.
Mature stands respond to P, young to N, in aboveground growth. NP no better.
Adding N decreases soil respiration. No change with P addition.
P decreases sap flow, Ca increases sap flow.
Adding P increased microbial P, adding N decreased microbial N.
Root biomass is increased by both N and P addition.
INTERACTIONS
N uptake by plants and/or microbes increases in response to P addition.
Foliar N is reduced by P addition.
MECHANISMS
Foliar N and P resorption are increased by P and N additions, respectively.
Roots forage for P when P is not added, grow more when N is added.
Soil phosphatase is higher where N availability is high
…rooting depth? AM/EM dominance? …
4. NLIMITATION
PLIMITATION
CHALLENGES TO BALANCED NUTRITION
MECHANISMS FAVORING BALANCE
P binding
N fixation
N deposition
EM fungi
enzymes
shallow roots
N resorption
weathering
tree allometry
P fertilization
N losses
AM fungi
enzymes
deep roots
P resorption
N fertilization
Editor's Notes
Tim was going to be a key presenter in this session, but he had a bike accident two weeks ago, on June 28. The good news is that he went home from the hospital on Friday, and he’s back in business—mental function unimpaired, and we need him for this grant proposal. The bad news is that he has fractures in 6 ribs, his pelvis, and his shoulder blade.
Please pick up one of these diamonds and write a note for Tim. We will assemble them to tile a plane and give it to him as a poster.
Tim was going to be a key presenter in this session, but he had a bike accident two weeks ago, on June 28. The good news is that he went home from the hospital on Friday, and he’s back in business—mental function unimpaired, and we need him for this grant proposal. The bad news is that he has fractures in 6 ribs, his pelvis, and his shoulder blade.
Please pick up one of these diamonds and write a note for Tim. We will assemble them to tile a plane and give it to him as a poster.
Tim was going to be a key presenter in this session, but he had a bike accident two weeks ago, on June 28. The good news is that he went home from the hospital on Friday, and he’s back in business—mental function unimpaired, and we need him for this grant proposal. The bad news is that he has fractures in 6 ribs, his pelvis, and his shoulder blade.
Please pick up one of these diamonds and write a note for Tim. We will assemble them to tile a plane and give it to him as a poster.
