Poplar Plantations for Water Sustainability in the Southeastern USA.

Benefits and Concerns for Food, Energy, and Water Resiliency and Sustainability

Dennis Hazel, Harry Daniels, Shawn Shifflett, Damian Shea, Allison Culbreth, Solomon Ghezehei, Andrew McEachranDepartment of Forest and Environmental Resources

Wanda Bodnar (UNC-Chapel Hill), Mark Strynar (USEPA), Andrew Birch (NCDEQ)

NC Bioenergy Research InitiativeUSGS WRRI

NC Sea GrantUSDA/NIFA Water for Agriculture

City of Jacksonville, Town of Garner, Gibson, Mt. Olive, Edenton

Nielsen, L., E. Guthrie Nichols, D. Hazel. 2012. A GIS Database of Municipal Waste Land Application Sites in North Carolina for Potential Bioenergy/biofuel Crop Production

acres

1990s presentMixed pine/hardwoodSycamoreSweet gumGreen AshBald cypressRiver birchPopulus (2012)

City of Jacksonville6,000 ac (2,000 irrigated)

Slow-rate Forest Land Application (1” to 3” week) Secondary-treated municipal wastewater15 to 30 years, 50” ww + 50” rainfall per year

Nutrients & Metals

Regulated Organics

?

Hydrologic Function & Non-Regulated Contaminants

http://www.cascade-earth.com/default.aspx

HardwoodsHigh Intensity PineMixed Tree systems

BIOENERGY?

Water & Forest Resiliency and Sustainability for SE USA

Bald cypress

Sycamore

Natural stand –eastern cottonwood

Hybrid poplar – 1 yr

Sweet gum –coppiced twice

Loblolly pine

Ghezehei, S., Shifflet, S., Hazel, D, E. Guthrie Nichols. 2015. Journal of Environmental Management,160:57-66.

• Yes they are productive

• Competition for arable land for bioenergy?

• Need better forest management

BIOENERGY

BIOENERGYBIOENERGY

Right Water at the Right Place at the Right Time (USDA)

https://www3.epa.gov/climatechange/impacts/southeast.html

Wetter Winters

Salt Water Intrusion; Forest Death

Hotter, drier summers

Groundwater Capacity Use Areas

Forest Loss with Increasing Water Demands

Importance of Forest Water Reuse Systems• Maintaining forest lands• Provisioning wood products • Provisioning water for other agricultural crops

(directly or indirectly)• Regulating and provisioning surface water• Regulating and provisioning groundwater• Mitigating expected water availability variability• Mitigating expected salt water intrusion• Sequestering carbon• Regulating soil• Regulating GHG• Regulating biodiversity (forest and organisms)

Forested land-application of wastewater

• Avoidance of direct discharge• Lower costs (capital, energy) and

employs more people• Lower odor potential and high removal

of nutrients and BOD• Provision wood products and

bioenergy – optimized?• Groundwater recharge / water

storage?• Protect Water Quality?• GHG dynamics?• Biodiversity?

Hybrid Poplar Success – yes, if bedded0 yr

1 yr

2 yr

BED BED

BEDDED 49-177

NOT BEDDED 49-177

BEDDED DN-34

NOT BEDDED DN-34

BEDDED OP-367

NOT BEDDED OP-367

0.0

2.0

4.0

6.0

8.0

10.0

12.0

70% 75% 80% 85% 90% 95% 100%

Mea

n Vo

lum

e (d

m3 )

Percent Survival

Bedding generally improved survival for the evaluated genotypes, but the genotypes that produced the most volume tended to have lower survival.

Limitations:GenotypeWeed competitionPestsSecondary-treated WW

Primary wastewater and better genotypes

Trade offs:Lower productivity than intensive silviculturepractice – but that’s OK given associated services

Concerns…Frequent harvesting… Risk to soil compaction, cost, and loss of water infiltration

PPCPs release from convention sewage treatment plants are a concern for water-reuse and ecological toxicity

Pharmaceuticals?

Prescription DrugsHormones and reproductive effects1

Anti-depressants and behavioral effects2

Development of antibiotic resistance3

Mixtures effects4

PPCPs

Reference well

Upstream

Outlet

TA wells

TB wells

Non-irrigated stream

What happens to non-regulated contaminants (such as pharmaceuticals- PPCPs)

PPCPs?

PPCPs?soil

groundwaterPPCPs?

PPCPs?

PPCPs?

stream

Which PPCPs make it to surface water via soil infiltration and groundwater?

PPCPs in wastewater is variable

7d to 10d residence time reservoirs

Lack of use of particular PPCPsPhotodegradation

BiodegradationChemical degradation (pH swings – 11)

Sorption and sedimentation

Soil

GroundwaterWastewater

Caffeine

Presc/OTC

NSAIDs

Antibiotics

Cotinine

Caffeine

Presc/OTC

Hormones

Cotinine

Plasticizer

Presc/OTC

NSAIDsHormones

Plasticizer

0

50000

100000

150000

200000

Disc

harg

e (m

3 /da

y)

Natural Streamflow Wastewater

Sampling Dates

Greater fraction of wastewater in groundwater during low rainfall periods or intense rainfall (water discharge)

Low range 12% surface outletMedian range of 24%High range of 55%

The fraction of wastewater in surface waters (and PPCPs) is greatest during storm events and low rainfall periods.

Birch et al., 2016. Journal of Env. Quality

Do Forest Water Reuse Systems Export PPCPs?

X

XX

X

X

X

Surface water flow direction

PPCPs in Forest Water Reuse Systems are found at lower concentrations than downstream of conventional WWTPs.McEachran et al. (2015) Environ. Toxicol. Chem..

Pharmaceutical Compound

Forested LAS WatersGroundwater Surface

Literature ValuesSurface Waters

Pharmaceutical (ng/L) (ng/L) (ng/L)Cotinine 3-13 1-23 20-50a

Caffeine 6-25 5-7 105b

Carbamazepine 0-11 2 25a, 157c

Sulfamethoxazole 0-21 0-2 60-150a, 20b, 1c

DEET 6-150 6-80 22b

Trimethoprim 0-2 0-20 10-150a, 71c

Ibuprofen 0-2 0-2 200a, 28b

Erythromycin 0 0 3.4b

Estrone 0-20 0 3.6b

Naproxen 0-12 0-6 11a, 53c

Forest Water Reuse Design (FoRWD)…• We have more to learn!• Tree species, rotation matters but

there are trade-offs• Manage regulated and non-

regulated contaminants comparable to conventional WWTP treatment

• The potential role these systems can play for future climate change and water-reuse is exciting (but needs good science and stakeholder collaboration)

Mt. Olive, NC 10 yr old SycamoreTertiary-treated wastewaterDrip irrigation