Recommended
Recommended
More Related Content
More from melnhe
More from melnhe (20)
Recently uploaded
Recently uploaded (20)
HB 2018-Timing of foliar N and P resorption
- 1. Foliar N and P Resorption by Species and Treatment Dan Hong Tim Fahey Melany Fisk Mariann Johnston Ruth Yanai
- 2. Before the leaves fall… • Trees retranslocate nutrients from senescing leaves Nutrient conservation and recycling prior to frost damage = foliar resorption Tree growth Soil fertility Forest health
- 3. Single element hypothesis The resorption of an element should be lower when that element is in high supply. Multiple element hypothesis The resorption of an element should be affected by other elements available. Nutrient Availability NutrientResorption N Availability PResorption P Availability NResorption ?? Multiple element interaction
- 4. Single element hypothesis The resorption of an element should be lower when that element is in high supply. Multiple element hypothesis The resorption of an element should be affected by other elements available. Nutrient Availability NutrientResorption N Availability PResorption P Availability NResorption ? Multiple element interaction See et al. 2015. Ecology
- 5. Single element hypothesis The resorption of an element should be lower when that element is ADDED. Multiple element hypothesis The resorption of an element should be affected by other elements ADDED. Nutrient Addition NutrientResorption N Addition PResorption P Addition NResorption Multiple element interaction
- 6. Research questions: • How do foliar concentration and resorption vary with respect to nutrient additions (N, P, N+P & )? • How do species vary with nutrient additions? • Does the pattern of resorption change over time with nutrient additions? • If so, do certain species resorb more nutrients earlier in the litterfall season, or later?
- 7. Field Methods • Green leaves collected by tree in August of 2015 and 2016. • Litter collected in 2015 by plot. • Litter collected in 2016 by tree and by plot. Stand Green Leaves & Litter C1 C4 C6 C8 C9 HBM HBO JBM JBO Trip1: 10/7 – 10/9 Trip2: 10/17 – 10/19 Trip3: 10/21 – 10/23 Trip4: 11/4 – 11/6 2015 BE, RM BE, RM BE, RM BE, SM BE, SM BE, RM, SM BE, SM BE, SM BE, SM 2016 BE, PC, WB PC, WB, YB PC, WB, YB YB YB WB, YB YB PC, WB, YB YB Kara Phelps Me
- 8. Laboratory Methods • P and other elements by Optima 5300 DV ICP-OES (Perkin-Elmer) • Green leaves were ashed and hotplate-digested • Others are being microwave-digested by MARS 6 Microwave Digestion System (CEM) • N by a FlashEA 1112 analyzer (Thermo Scientific)
- 9. N N treatment p < 0.0001 P treatment p < 0.05 N * P p < 0.19 Species p < 0.0001 2015 Green Solid N:P of 14-16 Dotted N:P of 10-20
- 10. P N treatment p < 0.70 P treatment p < 0.0001 N * P p < 0.51 Species p < 0.15 2015 Green Solid N:P of 14-16 Dotted N:P of 10-20
- 11. N:P N treatment p < 0.0001 P treatment p < 0.0001 N * P p < 0.30 Species p < 0.05 2015 Green Solid N:P of 14-16 Dotted N:P of 10-20
- 12. 2015 Resorption
- 13. N N treatment p < 0.003 P treatment p < 0.97 N * P p < 0.98 Species p < 0.0001 Green leaf P concentrations (mg/g) 1 2 3 4 5 GreenleafNconcentrations(mg/g) 20 30 40 50 BE PC WB YB 2016 Green Solid N:P of 14-16 Dotted N:P of 10-20
- 14. P N treatment p < 0.01 P treatment p < 0.0001 N * P p < 0.40 Species p < 0.0001 Green leaf P concentrations (mg/g) 1 2 3 4 5 GreenleafNconcentrations(mg/g) 20 30 40 50 BE PC WB YB 2016 Green Solid N:P of 14-16 Dotted N:P of 10-20
- 15. N:P N treatment p < 0.0001 P treatment p < 0.0001 N * P p < 0.12 Species p < 0.0001 Green leaf P concentrations (mg/g) 1 2 3 4 5 GreenleafNconcentrations(mg/g) 20 30 40 50 BE PC WB YB 2016 Green Solid N:P of 14-16 Dotted N:P of 10-20
- 16. BE 0 6 12 18 24 Ca(mg/g) 4 6 8 10 12 14 PC WB YB Con N P NP Ca p < 0.002 Ca Con N P NP Ca Con N P NP Ca Con N P NP Ca BE 0 6 12 18 24 Mg(mg/g) 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 PC WB YB p < 0.07 Mg Con N P NP Ca Con N P NP Ca Con N P NP Ca Con N P NP Ca Al, B, Fe, K, Mn, Na, S, Sr, Zn
- 17. What now…? • 250 green leaf samples • 826 litter samples Thank you and stay tuned!
Editor's Notes
- Make sure the title matches the content. Maybe just green?
- Foliar nutrient concentrations are good indicators of growth, soil fertility, and forest health. They can provide a snapshot of how trees allocate their nutrients under different conditions, such as elevated levels of N and P.
- Craig See found that P resorption efficiency increased with soil N. P resorption increased with soil P, which goes against the hypothesis. P resorption was high with low resin-available P in Oe. N resorption was high with low
- Craig See found that P resorption efficiency increased with soil N. P resorption increased with soil P, which goes against the hypothesis. P resorption was high with low resin-available P in Oe. N resorption was high with low
- Don’t talk about time yet? Add a slide at the end about future work. Are leaves more sensitive to N or P.
- Mention highschool students.
- Adding N increased N concentrations, pushing it towards P-limitation. Adding P increased P concentrations but decreased N concentrations, to a point of co-limitation or even towards N-limitation. Adding N and P together prompted a shift towards co-limitation. BE remained in the P-limited zone even with P addition, but maples seemed to accumulate more P. Foliar N:P ratios increased with N and decreased with P addition. The solid and dotted lines delineate co-limitation between N:P of 14-16 and 10-20, respectively.
- Adding N increased N concentrations, pushing it towards P-limitation. Adding P increased P concentrations but decreased N concentrations, to a point of co-limitation or even towards N-limitation. Adding N and P together prompted a shift towards co-limitation. BE remained in the P-limited zone even with P addition, but maples seemed to accumulate more P. Foliar N:P ratios increased with N and decreased with P addition. The solid and dotted lines delineate co-limitation between N:P of 14-16 and 10-20, respectively.
- Adding N increased N concentrations, pushing it towards P-limitation. Adding P increased P concentrations but decreased N concentrations, to a point of co-limitation or even towards N-limitation. Adding N and P together prompted a shift towards co-limitation. BE remained in the P-limited zone even with P addition, but maples seemed to accumulate more P. Foliar N:P ratios increased with N and decreased with P addition. The solid and dotted lines delineate co-limitation between N:P of 14-16 and 10-20, respectively.
- P resorption efficiency declined with P addition, but no effect of N or P addition on N resorption efficiency
- Adding N increased N concentrations and decreased P concentrations, pushing it towards P-limitation. Adding P increased P concentrations, to a point of co-limitation or even towards N-limitation. Adding N and P together prompted a shift towards co-limitation. PC accumulated more N than the birches. PC accumulated more P than BE and WB. Foliar N:P ratios increased with N and decreased with P addition.
- Adding N increased N concentrations and decreased P concentrations, pushing it towards P-limitation. Adding P increased P concentrations, to a point of co-limitation or even towards N-limitation. Adding N and P together prompted a shift towards co-limitation. PC accumulated more N than the birches. PC accumulated more P than BE and WB. Foliar N:P ratios increased with N and decreased with P addition.
- Adding N increased N concentrations and decreased P concentrations, pushing it towards P-limitation. Adding P increased P concentrations, to a point of co-limitation or even towards N-limitation. Adding N and P together prompted a shift towards co-limitation. PC accumulated more N than the birches. PC accumulated more P than BE and WB. Foliar N:P ratios increased with N and decreased with P addition.