Tanvir KhanEnvironmental Engineering Doctoral Program

Department of Civil & Environmental EngineeringMichigan Technological University

Q1 RESEARCH UPDATE

11/14/2013

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• Atmospheric-surface exchangeable pollutants (ASEPs)• Terrestrial-atmosphere exchange processes of ASEPs• Air-water• Air/soil-plant

• Research questions (Q1 – Q3)• Components of Q1 Tasks

• Environmental compartments of ASEPs• Parameters for database development for PAHs and PCBs• Parameterization for various environmental compartments • Air-surface exchange parameterization

• Comparison of global models of terrestrial net primary productivity

Presentation Outline

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Atmosphere-Surface Exchangeable Pollutants (ASEPs)

Atmosphere

Surface

ASEP characteristics

Resist rapid degradation

Accumulate in organic rich

media

Semivolatile

Proposed compounds to study:(1)Mercury (Hg) (2)Polycyclic aromatic hydrocarbons (PAHs)(3)Polychlorinated biphenyls (PCBs)

Sequestration

Atmospheric transport

Deposition

Natural &secondaryemission Ecosystem impact,

process change

Well-being

StressorsPopulation

growth Land use/cov

erEnergy

sourcesAnthropogenic

emissionClimat

echange

Perceptions,beliefs, goals

Governance,adaptation

Socioeconomicactivity

Human ASEP System

Safe waterSafe

air

Safe food

Ecosystem Services

Biogeochemical Cycle of ASEPs in Nature

Dynamically Coupled Human-Natural ASEP System

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Air-Water Exchange Process of ASEPs

Gas/particle partitioning

Wet deposition(particle + gas)

Dry depositio

n(particle)

Air-water exchange

Dissolved-phase Hg(0) DOM-

bound POPs

Sediment-bound POPs and Hg (II)

Dissolved-phase POPs,

Hg (II)

Dissolved-phase

POPs, Hg (II)Particle-

bound Hg (II), POPs

Particle-bound

POPs, Hg (II)

Gas-phase Hg (0)

Atmosphere

Gas-phase POPs, Hg

(II)

Resuspension

Settling Diffusive exchange

Water column

Inputs Loss through outlet

Burial into deep sediment

Surface layerSediment

Degradation

Rowe et al. (2008)

POPs=Persistent Organic Pollutants

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Air-Soil/Plant Exchange Process of ASEPsAtmosphe

reWet deposition(particle +

gas)

Particle dry

deposition

Top soilDiffusion

Reemission/Volatilization from soil

Intermediate soil

Reservoir Layer

Leaching

Burial

Uptake by plant

coverReemission/

Volatilization from plant cover

Uptake by plant root

Degradation

Gaseous dry

deposition

Palm et al. (2004)

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Low latitudes

(Re-emission > deposition)

Long-range atmospheric transport

Mid-latitudes(Re-emission and

depositiondominated by seasonal

cycles)

High latitudes(Deposition > Re-

emission)

Global Distillation

‘Grasshopping’ effect

Global ASEP Cycling

Vallack et al. (1998)

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Research Questions “What features of secondary emissions lead to added impact, in terms of elevated deposition, to ecosystems, now and in future, and in what environments does ASEP sequestration mitigate ecosystem service losses?”

Q1

“How will alteration in global secondary emissions of Hg due to global change alter U.S. regional household income due to health effects caused by fish consumption, and what assumptions are needed to extend this work to other ASEPs?”

Q2

“How can governance be improved to reduce the negative impacts of ASEPs and enhance adaptive management across multiple jurisdictional scales?”

Q3

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Tasks Involved in Answering Q1Model

Development

A) Development of PCB and PAH GEOS-Chem models (Selin Group)[Sensitivity analysis]

B) Improved method to incorporate land use/cover effects on ASEP cyclingC) Incorporate new ASEP air-surface exchange parameterizationsD) Improvement in NPP-ASEP coupling [Sensitivity analysis]

E) Scenario developmentF) Historical and current simulationsG) Future simulationH) Atmospheric deposition to fish[Sensitivity analysis]

Model Improvement

Model Applications

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Model ASEP Environmental Compartments

Lakes, rivers

Soils

Ocean

Lake, river, and ocean sediments

Leaves and grass

Snow/ice

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Parameters Needed to Describe PAH and PCB Measurements in soils

Sampling location details: Latitude, longitude, altitude, land utilization type, population in the sampling area, distance from major road networks, etc.

Types of soil: Natural, forest soil, urban, rural, upland soil, industrial soil, grassland, waste water irrigated soil, arable/paddy soil, etc.

Types of contamination:Non-contaminatedweakly/heavily contaminated

Depth of sediment core sampled: Minimum/Maximum/average depth

Sampling/identification technique

Other soil parameters: Black carbon content Organic matter content Organic carbon content Sediment grain size distribution Soil pH

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Surface microlayer measurement:Temperature Relative humidity Atmospheric pressure Wind direction/speed Sun irradiation

Concentrations of PCBs/PAHs:Dissolved, particulateconcentration in air concentration in water

Other parameters:Henry’s law constant Fugacities

Deep-ocean measurement:Sampling location, date (time period) meteorological parameters

Water quality parameters:oxygen contentSalinitytemperature

Parameters Needed to Describe PAH and PCB Measurements in Oceans, Rivers, and Lakes

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Parameters needed for snow/iceSampling location details:

Sampling period, geographic location (latitude, longitude, altitude)

Meteorological parameters: Annual precipitation, Snow precipitation, temperature, etc.

Snow sample characteristics: Sample types: (core or layer?)Snow depth Snow density Water equivalents Suspended particulate matter concentration in snow

PAH/PCB fluxes in snowPAH/PCB concentration:

Total PAH/PCB concentrationIndividual PAH/PCB concentration

Sampling location details: Types of forest (examples: deciduous, boreal coniferous forest, etc.)

Leaf characteristics: Leaf areaLipid contentExposure time

Sampling/identification techniques:Sampling tools Storage devicesExtraction methods

Parameters needed for leaves/grass

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Air-surface Exchange Parameterization

Mass concentration based model: Dissolved concentration (Cw)Gas-phase concentration (Ca)Mass-transfer coefficient (ka/w)Flux (F)

Fugacity based model:Dissolved concentration expressed in fugacity (fw)Gas-phase concentration expressed as fugacity (fa)Mass transfer coefficient (Daw) Flux (F)

Additional parameters:Molecular weight Henry's law constant Temperature Octanol-air partition coefficient (Koa)……more….

Concentrations of ASEPs:in soil (Cs) in air (Ca)

Fugacities of: in soil (fs)in air (fa)

Other soil parameters: Fraction of organic matter (fom) Octanol-air partition coefficient (Koa) Soil water partition coefficient (Kd) Soil air partition coefficient (Ksa) Henry's law constant Soil bulk density Aqueous solubility…..more…

Air-water exchange parameters

Air-soil exchange parameters

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Comparing Global Models of Terrestrial Net Primary Productivity

Terrestrial models of

biogeochemistry

Satellite-based models

Models for seasonal fluxes and vegetation

structure

Models for seasonal fluxes

CASA, GLO-PEM, SDBM, SIB2, and TURC #5BIOME-BGC, CARAIB 2.1, CENTURY 4.0, FBM 2.2, HRBM 3.0, KGBM, PLAI 0.2, SILVAN 2.2, and TEM 4 #9

BIOME3, DOLY and HYBRID 3.0 #3 Major processes are:

(a) Photosynthesis(b) Growth and maintenance

respiration(c) Evapotranspiration

(d) Uptake and release of N(e) Allocation of photosynthate to

various parts of plant

(f) Litter production and decomposition Cramer et al.

(1999)

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Comparison of Three Model Types

Satellite based models

Models for seasonal fluxes

Models for seasonal fluxes and vegetation

structure

1. Use satellite data2. Determine temporal behavior of

photosynthetically active tissue3. Asses climate variability of NPP

1. Use soil and climate characteristics to simulate fluxes

2. Describe functional changes within particular vegetation type

3. Possible re-distribution of vegetation is ignored

1. Equilibrium between climate and vegetation is assumed

2. Simulate changes in both ecosystem structure (vegetation distribution) and function (biogeochemistry)

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THANK YOU.

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ReferencesCramer et al. (1999) Comparing global models of terrestrial net primary productivity (NPP): overview and key results, Global Change Biology (5), 1-15Palm et al. (2004),Evaluation of sequentially-coupled pop fluxes estimated from simultaneous measurements in multiple compartments of an air–water–sediment system, Environmental Pollution (128) 85–97.Rowe, M.D. (2008), State Of Lake Superior, Ecovision World Monograph Series, Burlington, Canada.Vallack et al. (1998), Controlling persistent organic pollutants–what next?, Environmental Toxicology And Pharmacology (6) 143–175.