Restoring woody biomass and carbon storage through tree

Restoring woody biomass and carbon storage through tree planting under varying hydrologic regimes J. E. Perry and H. W. Hudson 2015 SWS SAC Annual Meeting Athens, GA 26 Oct. 2015

Problem • Returning woody biomass with appropriate species to restored forested wetlands is not always successful (Shear et al. 1996, Morgan and Roberts 2003, Atkinson et al. 2005, Matthews and Endress 2008, De. Berry and Perry 2012, Charles 2013) • Quantifying biomass and carbon accumulation is challenging for saplings – Very few established equations for saplings – Sampling difficulties • We established an experimental field site to address these issues among others

Seven Species Three Stocktypes Variety of environmental conditions Bare Root (BR) Betula nigra (River Birch) Liquidambar styraciflua (Sweetgum) Platanus occidentalis (Sycamore) Tubeling (TB) Salix nigra (Black willow) Hydrology (Cells) Ambient Saturated Flooded Soil texture Sand Silt Clay Soil nutrients Carbon (OM) Nitrogen Phosphorus Quercus bicolor (Swamp white oak) Quercus palustris (Pin oak) Quercus phellos (Willow oak) 1 Gallon Container

Environmental Characteristics

Tree Morphological Measurements Measured 3 x/year (6 Years) Survival Height Crown Diameter at Breast Height (DBH) (convert to area) 1. 4 m (4’ 7”) Stem Cross-Sectional Diameter at Groundline (SCDG) (convert to Stem Cross-Sectional Area at Groundline (SCAG))

346 Trees Removed Above- and below-ground leafless biomass Winter 2011/12 – Year 3/4

221 Trees Removed -- Above-ground only 2013/14 – Year 5/6

Functional Groups: based on traditional forest successional sequence, differences in maturation and growth rates, dispersal mechanisms, and disturbance tolerance. Primary Species: consisted of 4 woody species (B. nigra, L. styraciflua, P. occidentalis and S. nigra) that are typically dominant during the early stages of succession. - have rapid growth and maturation rates, - have wind dispersed seeds and - are moderately tolerant of disturbance. Secondary Species: consisted of 3 species (Q. bicolor, Q. palustris, and Q. phellos) typically dominant in the later stages of succession. - have slower growth and maturation rates, - have large seeds that are dispersed mainly by animals and - are generally less tolerant of disturbance.

BGB ~ AGB (2011/12, n=346) BGB = a * AGBb + ε (Power-law equation ) • Generalized nonlinear least-squares regression (Pinheiro and Bates 2000) • Variance structure was modeled using the power of the covariate

Total Biomass ~ ESCDG (n=567) TBIO = a * ESCDGb + ε (Power-law equation) Estimated BGB (2013/14) using AGB and previous relationship Convert multiple SCArea. G to equivalent SCDiameter. G Determine relationship between ESCDG and total leafless biomass

20, 077 kg 9, 035 kg 196 kg a a b n=257 n=225 n=271 • AMB>SAT>FLD • PRI>SEC (AMB & SAT) b a a n=265 n=210 n=30

Calculated plant growth rates (AGR, RGR) from non-linear model (monomolecular) of ln(biomass) ~ time (Paine et al. 2012) Captures time and size dependent changes in growth

Discussion • AGB~BGB Departure from isometric relationship – Decreasing r: s ratios as trees grow • Total biomass ~ Stem Diameter – Coefficients (b) >= literature values with similar sapling species • Inclusion of BGB and early measurements • Biomass and Carbon after 6 years – AMB>SAT>FLD – PRI>SEC (AMB & SAT) PRI=SEC (FLD) • AGR and RGR: Primary accumulate more C than Secondary and at faster rates.

Conclusion – BEM can be used to determine the role of planted woody saplings in restoring carbon cycle function in created/restored forested wetlands; – Primary species biomass > Secondary species biomass after 6 years; – Stressful conditions reduce carbon accumulation.

Additional Research • Habitat Evaluation • Impact of Competition – Developed competition index based on nearest competing neighbors and biomass • Economic Analysis

Acknowledgements

OK –that’s all. Now where’s the BEER!

Wetland Restoration • Returning woody biomass is an important goal of forested wetland restoration – Trees are the dominant ecosystem structure in mature forested wetland systems (Rheinhardt et al. 2012) – Woody biomass production is an important ecosystem function and serves as an indicator of other functions and services • • • Accumulation and cycling of carbon and other elements Roots prevent erosion Potential flora and fauna habitat (food, shelter etc. ) Modify hydrologic regime Provides organic matter to downstream ecosystems • Trees are established in restored forested wetlands through natural colonization or tree planting

Sample Summary Primary Species Secondary Species Equivalent Stem Cross-Sectional Diameter at Groundline (cm) 0. 2 – 34. 3 0. 3 – 10. 5 Height (cm) 4 – 1155 9 – 710 Canopy Diameter (cm) 1 – 775 1 – 343 BGB (kg)* 0. 001 – 144. 6 0. 002 – 9. 9 AGB (kg) 0. 001 – 143. 8 0. 001 – 15. 5 Total Biomass (kg) 0. 002 – 273. 0 0. 003 – 19. 9 Average Root: Shoot (2011 Only) 1. 46 2. 26 Average Percent Carbon (2014 Only) 46. 7 46. 4 Average Percent Nitrogen (2014 Only) 1. 3 1. 4

Summer 2013 - Year 5

Bulk Density Percent Sand, Silt, Clay Percent C, N, P

Acknowledgements Peterson Family Foundation Wetland Studies and Solutions, Inc. Virginia Department of Forestry, New Kent Forestry Center Jim Perry, Liz Canuel, Randy Chambers, Frank Day, Mike Aust Lori Sutter, Sean Charles Chris Hauser Field Workers Master Naturalists Master Gardeners Friends of Dragon Run Christopher Newport University (Dr. Rob Atkinson) W&M, VIMS and ODU Students Friends and Family NSF GK-12 (DGE-0840804) Thanks! hwhudson@vims. edu @hwhudson 3