Surprising natural variation in nutrient availability and nutrient

Surprising natural variation in nutrient availability and nutrient resorption Craig See SUNY-ESF Photo: USFS

Before the leaves fall. . . 45 -63% less nitrogen 43 -73% less phosphorus (Boerner 1984) • Nutrients move from leaves to stem tissues • Resorption Efficiency = percent of leaf nutrients resorbed before abscission • Is it a predictor of site nutrient status? • Higher efficiency in nutrient poor sites (Flanagan and Van Cleve 1983, Boerner 1984) • No effect (Chapin and Moilenan 1991, Schlesinger 1989)

Resorption in the MELNHE stands In 2009, trees in mid and old stands resorbed more phosphorus relative to nitrogen than in the younger stands.

2010 Methods • Stands Sampled: Young: C 1, C 2 Mid: C 4, C 6, HB-mid, JB-Mid Old: C 8, C 9, HB-Old, JB-Old • Fresh leaves sampled August, litter sampled in October • Stand level resorption efficiency calculated as the mean of plot efficiencies. • STILL PRETREATMENT

90% 2009 BEECH 80% Resorption Efficiency 70% 60% 50% 40% 30% 20% 10% 0% C 1 C 2 C 4 C 6 C 8 C 9 HB-M HB-O JB-M JB-O 2010 BEECH 90% 80% Resorption Efficiency 70% 60% 50% 40% 30% 20% 10% 0% C 1 C 2 C 4 C 6 C 8 C 9 HB-M HB-O JB-M JB-O

90% 2009 SUGAR MAPLE 80% Resorption Efficiency 70% 60% 50% 40% 30% 20% 10% 0% C 1 C 2 C 4 C 6 C 8 C 9 HB-M HB-O JB-M JB-O 2010 Sugar Maple 90% 80% Resorption Efficiency 70% 60% 50% 40% 30% 20% 10% 0% C 1 C 2 C 4 C 6 C 8 C 9 HB-M

90% 2009 YELLOW BIRCH 80% Resorption Efficiency 70% 60% 50% 40% 30% 20% 10% 0% C 1 C 2 C 4 C 6 C 8 C 9 HB-M HB-O JB-M JB-O 2010 Yellow Birch 90% 80% Resorption Efficiency 70% 60% 50% 40% 30% 20% 10% 0% C 1 C 2 C 4 C 6 C 8 C 9 HB-M HB-O JB-M JB-O

Root P Concentrations by Stand

1 2 3 4

C 8 ROOT P CONCENTRATIONS (0 -10 cm depth) 1 2 3

AVAILABLE SOIL P FROM RESIN STRIPS Oe layer Oa layer 40 25 35 20 Resin P (ug/g) 30 25 20 15 10 10 5 5 0 0 1 2 3 4 B layer 3 2 Resin P (ug/g) 15 2 1 1 0 1 2 3 4

CUMULATIVE P CONCENTRATION FOR AMMONIUM CHLORIDE + PEROXIDE + COLD NITRIC ACID LEACHES 0, 180 0, 160 P Concentration (mg/g) 0, 140 0, 120 0, 100 0 -10 cm 0, 080 10 -30 cm 30 -50 cm 0, 060 0, 040 0, 020 0, 000 1 2 Plots 3

FOLIAR CONCENTRATIONS Beech 1, 6 1, 4 1, 2 1 0, 8 fresh leaves 0, 6 litterfall 0, 4 1 0, 8 0 0 3 4 1 Yellow Birch 2 1, 8 1, 6 1, 4 1, 2 1 0, 8 0, 6 0, 4 0, 2 0 fresh leaves litterfall 1 2 3 4 litterfall 0, 4 0, 2 2 fresh leaves 0, 6 0, 2 1 Phosphorus (mg/g) Sugar Maple 2 3 4

Conclusions • Data suggests that site nutrient availability does affect nutrient resorption • Many of the MELNHE stands (Not C 8 -3) may be phosphorus limited • Nutrient limitation at what scale?

Thank You • • • Ruth Yanai Melany Fisk Steven Hamburg Tim Fahey Matt Vadeboncoeur Doug Ryan Kikang Bae Shinjini Goswami Braulio Quintero Shoestring Crew

REFERENCES Aerts, R. 1996. Nutrient resorption from senescing leaves of perennials: Are there general patterns? Journal of ecology 84: 597 -608 Boerner, R. 1984. Foliar nutrient dynamics and nutrient use efficiency of four deciduous tree species in relation to site fertility. Journal of Applied Ecology, 21: 1029 -1040 Chapin, S. , and L. Moilenan. 1991. Nutritional controls over nitrogen and phosphorus resorption from Alaskan birch leaves. Ecology 72: 709 -715 Cote, B. , J. W. Fyles, H. Djalilvand 2002. Increasing N and P resorption efficiency and proficiency in northern deciduous hardwoods with decreasing foliar N and P concentrations. Flanagan, P. W. , and K. Van Cleve. 1983. Nutrient cycling in relation to decomposition and organic matter quality in taiga ecosystems. Canadian Journal of Forest Research 13: 795 -817. Ryan, D. F. , Bormann, FH. 1982. Nutrient resorption in northern hardwood forests. Bioscience 32: 29 -32. Schlesinger, W. H. , E. H. De. Lucia, and W. D. Billings. 1989. Nutrient-use efficiency of woody plants on contrasting soils in the western Great Basin, Nevada. Ecology 70: 105 -113