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Where Innovation Is Tradition The Impact of Regional Development on Symbioses From the Potomac River...
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Where Innovation Is Tradition
The Impact of Regional Development on Symbioses From the Potomac
River Valley to the Chesapeake Bay
Maheen AzizAdam Carpenter
Eileen FlynnPete GoddardDana Griffith
Richard GrooverDamien HammondLaruen W. KinneCharles Milling
Dr. Dann SklarewWendy Stickel
Julia Welch
Where Innovation Is Tradition
Tonight’s Agenda
• Introduction
• Stressors to the PRV• Types and Causes
• Effects on Symbiosis• Terrestrial, Freshwater, and Brackish Ecosystems
• Prospects for the Future• Challenges and Remediation
• Conclusion
Where Innovation Is Tradition
I. Introduction
Potomac River Valley
Photo: http://tinyurl.com/sklarew2000
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What is symbiosis?
• “Two or more forms of life that have a relationship which may change over time which influence each other. “ Jan. 21, 2010
• What is mutualism?• “Interaction between species which benefits
both… a +/+ interaction” (Boucher et al. 1982)
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Thesis
• Development has begun to place stressors on the symbioses in the PRV, thus creating the potential for fundamentally altering the ecosystem services of those symbioses.
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Ecosystem Services in the PRV• Ecosystem Services: contribution of ecosystems to the benefit of populations, to both our physical
and psychological well-being. Not defined separate from human values (EPA, 2009).
• Provisioning Services-Oysters
• Regulating Services-Pollination
• Cultural Services-Aesthetics of the River
• Supporting Services-Mycorrhizae
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II. Environmental Stressors as a Result of Development
• Habitat degradation/fragmentation• Sediment• Nutrients (phosphorous & nitrogen)
• Endocrine disruptors (DDT, PCBs, etc.) • Toxics (heavy metals)
• Organic pollutants (medicines, hormones)
• Flow regimes
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• Suburban sprawl increases habitat destruction and fragmentation• Lots of clear-cutting• Lot sizes increased• Loss of contiguous forest• Loss of mycorrhizal associations
II. Environmental Stressors as a Result of Development
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• Habitat alteration allows for multiple stressors on ecosystem • Higher salinity• Changes in acidity/ alkalinity• Removal or uptake of nutrients in soils and
watersheds• Introduction of heavy metals into environment
II. Environmental Stressors as a Result of Development
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• Pollution• Nutrient runoff from the mainland can increase
nutrients in the water and cause algal blooms that cover and destroy the existing underwater vegetation.
• Pesticides, oil, and sediment can also be included in runoff from the mainland.
II. Environmental Stressors as a Result of Development
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Emerging Contaminants & the PRV
• 2004 in West Virginia tributaries of Potomac river
• USGS finds that 44 percent of male Smallmouth bass produced eggs and exhibited female
• “Intersex” fish, alligators, and frogs
• Endocrine disrupting compounds
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Nonpoint Source Pollution
• Nonpoint source pollution generally results from land runoff, precipitation, atmospheric deposition, drainage, seepage or hydrologic modification.
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Nonpoint Source Pollution
• Excess fertilizers, herbicides and insecticides from agricultural lands and residential areas
• Oil, grease and toxic chemicals from urban runoff and energy production
• Sediment from construction sites, crop and forest lands, and eroding stream banks
• Salt from irrigation practices and acid drainage from abandoned mines
• Bacteria and nutrients from livestock, pet wastes and faulty septic systems
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• Commerce• Detrimental oyster collecting techniques and deep
water trawling• Harvesting of different species for human
consumption• Ships that come into port bringing invasive
species and diseases.
II. Environmental Stressors as a Result of Development
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• Erosion:• Loose silt, sand and clay released in the environment
as sediment (sedimentation)• Nutrient run-off• Increased turbidity
• Carried through streams and rivers the Chesapeake Bay by surface run off.• One of the leading causes of the Bay’s decline.1
• Symbiosis affected at all levels. Chesapeake Bay Program. 2009. Sediments. http://www.chesapeakebay.net/sediments
II. Environmental Stressors as a Result of Development
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III. Impacts of Urbanization on Symbioses in the PRV
• Terrestrial– Mycorrhizae & Plants– Pollinators & Plants
• Aquatic• Freshwater
– Mussels & Fish– Shrimp & SAV
• Brackish water– Multiple Oyster Mutualisms– SAV
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A. Terrestrial: Mycorrhizae Fungi
Mycorrhizae: form mutualisms with plants• Ectomycorrhizae-form
sheaths around the roots of partner plants
• Endomycorrhizae-invade interior root cells of host plants
(Stamets, 2005)
(Margulis & Fester Eds., 1991) http://www.palaeos.com/Plants/Lists/Glossary/Images/
Endomycorrhizae.gif
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Mycorrhizae and herbaceous plants:
• Wild leeks (also called ramps) form mutualistic relationships with mycelium which promotes leek health by:
– Bioremediation
– Increasing surface area for water uptake
– Changing physical and chemical properties of soil
(Leyval & Binet, 1998)
http://greayer.com/studiog/wp-content/uploads/2009/04/mosaic1602239.jpg
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Impact of fossil fuel emissions
• Fossil fuels release polyaromatic hydrocarbons (PAHs)
• Increasing amounts of PAHs in the soil decrease mycorrhizal colonization of plant roots
• Plants with mycorrhizal associations are able to survive and grow in soils with higher amounts of PAH than plants without these associations
(Leyval & Binet, 1998)
(Bouchez et. al, 1995)
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Impact of Clear Cutting
• Removes Native Plant Species such as Virginia Pine (Pinus virginiana)
Photo: http://www.forestwander.com
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Impact of Clear Cutting
Study by Liu et al. (2001) found:• Clear-cutting and burning led to deficiency in
available nitrogen• Nitrogen fixation decreases for 18 months• Overall soil degradation occurs due to erosion
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Impact of Clear cutting
Removes top soil and associated mychorrhizae such as Thelephora terrestris
Photo: http://aboutenvironment.com/
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B. Terrestrial: Pollinators
Alfalfa Leafcutter, Megachile rotundata
>90 crops are benefited by honey bee
Alfalfa leafcutter bee pollinates alfalfa for seed
Bumblebees used for pollination services in greenhouses
(Sanford, 1998)
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Pollination Services in VA
Commercial honey bee hives scattered throughout holly orchard - Appleton et al., 2009
$23 million added value to apple industry
Major factors threatening pollinators
Loss of habitatLoss of symbiotic
partnerUse of pesticides
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In the freshwater PRV:•Historically the area supported 14 species of mussels
•Presently 7 species live in the PRV-two of which are Yellow lamp mussel (Lampsilis
cariosa) and tidewater mucket (Leptodea ochracea)-white perch is often a host along with other species
http://www.lsc.usgs.gov/SPN.asp?StudyPlanNum=02098
C. Aquatic (freshwater): Mussels & fish
bio.umass.edu
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Symbiosis between mussels & fish
•Fish hosts are requirement for mussels to complete their life cycle.
•Larvae attach to the gills or fins of the host and remain attached for one to four weeks while transforming into a juvenile mussel. As juveniles, they drop off the fish and begin their free-living life.
•Mussels have adaptations that ensure host interest such as mantles that resemble prey items (worms, etc) or mating colors and body shape similar to the host fish.
•Mussels lure the fish in and release the larvae into the water column or grab the fish by the head and inject the larvae into the gills or fins.
Help save America's pearly mussels - Virginia cooperative extension
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Ecosystem function:Mussels benefit the ecosystem by removing algae and suspended particles in the water column, especially from turbid and organically enriched waters near wastewater facilities and in fish farm effluents. Mussels repackage nutrients and mix the upper sediment layer.
*Evidence from cancer research suggests that some mussels may be resistant to certain types of cancer and that the extraction of cancer-curing drugs from mollusks may be feasible in the future.
http://www.lsc.usgs.gov/SPN.asp?StudyPlanNum=02098
C. Aquatic (freshwater): Mussels & fish
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Impact of Sedimentation
Help save America's pearly mussels - Virginia cooperative extension
•Sedimentation deeper than 2mm shown to cause 100% mortality in white perch larvae
•Decrease in fish population will decrease mussel population, affecting rate of filtration
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D. Aquatic (freshwater): Shrimp & Wild celery
Freshwater grass shrimp Palaemonetes paludosus &Wild celery Vallisneria americana
•Sherpaguides.com/chesapeake_bay/natural_history(Lowe et. Al, 1990)
www.mass.gov
Petshrimp.com
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Relationship/Ecosystem Function:•Grasses produce oxygen, hiding places and food
•Shrimp feed on algae, detritus, aquatic insects, crustaceans, and meiofauna and, in turn, are eaten by fishes and other predators
•Sherpaguides.com/chesapeake_bay/natural_history•(Lowe et. al, 1990)
D. Aquatic (freshwater): Shrimp & Wild celery
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Impact of Erosion and Nutrient Loading
•Nutrient loading (from development) can cause algal blooms that cloud the water, blocking light to grasses
•Urban sprawl produces 5-7 times more sediment and phosphorus than an old-growth forest
•Only 11% of the Bay’s historic SAV grasses remain
Pant, H and Reddy, K. Phosphorus Sorption Characterizes of Estuarine Sediments under Different Redox Conditions www.sacramentoaquariumsociety.org
Thekrib.com
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E. Aquatic (Brackish): Oyster Mutualisms
• Filter feeder
• Reef-builder
• Substrate for invertebrates
• Nutrient-cycler
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Role of oysters in PRV• Decades of over-harvesting have substantially reduced
role of oysterloss of crucial ecosystem services:
• Reduced grazing of phytoplankton has led to increased turbidity and reduced photosynthesis by SAV
• Lower rate of filtration = less effective curb on pollution• Reduced reefs, reduced refuge and limited substrate has led to
reduced species richness and fish abundance• Fewer biodeposits to fertilize sea grasses
• Contributes to reduced resilience of entire estuarine eco-system
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Impact of development on oysters & sea grass
• Excessive nutrient flows create algal blooms which lead to hypoxia, limiting supply of oxygen to oysters and other benthic fauna.
• Siltation increases turbidity, affecting density of sea grass communities which offer refuge to oyster (and other) larvae.
Photo: http://www.life.umd.edu Photo: http://www.chesapeake-bay.org
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Impact of development on oysters & sea grass
• Hydrological flow regimes which limit flow of freshwater in PRV increase salinity levels, exacerbating population of protozoa that cause Dermo disease
• Years of dredging have reduced height of oyster reefs exposing surviving oysters to increased risks of hypoxia, reducing further what is left of the oyster population and creating barriers to restoration.
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Positive Feedback Loops
• Increased turbidity decline of seagrasses no buffer for wave action increased re-suspension of sediment increased turbidity decline of seagrasses (Newell and Koch 2004)
• Loss of reef substrate decline of sea-nettles increase in comb jellies increased predation on oyster larvae reduced oyster abundance loss of reef substrate (Goldman 2004)
• The “eutrophication cascade”: increased nutrient loadingphytoplankton growth and sinkingincr benthic respirationincr recycling of N and Pincr nutrient-fed phytoplankton growth (Kemp 2005)
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F. Aquatic: Submerged Aquatic Vegetation (SAV)
• A foundation species with multiple roles:
• habitat and refuge• flow management• nutrient buffering
• Dramatic decline in SAV from 1950s
• Recent signs of recovery
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Causes of SAV Decline
• Primary cause is poor water quality from pollutants• SAV as “canary of coastal water”• Chlorine and other chemicals• Herbicides• Sediments and algal blooms affecting turbidity
• Other causes-Over-grazing-Warming of water temp-Storm events -Disease
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IV. Conservation
A. Human Land Use Changes (policy & action)1. Strategic development2. Treatment facilities3. Cultural changes 4. Changes in Regulatory Structures
B. Bioremediation1. Bioindicators2. Symbioses as agents of bioremediation
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A. Human Land Use Changes
• Considerations of Land Use is Required to Address Environmental Issues including Global Climate Change1
• Development in theory is not that bad– It is the WAY we develop
• Loss of forests and native species, as well as top soil
• Impervious surfaces
• Fragmentation of existing forestland
• Construction Areas• Existing Roadways
1Lecture: Lovejoy, April 8, 2010
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• Larger Environmental Easements and Buffers• Remove Native Species Only Where Necessary • Leave Layer of top soil and at least 30 percent of existing
plant species– Mychorrhizae associations provide services
• Soil formation and retention• Absorption of naturally occurring phosphorous
• Develop Fewer Impervious Surfaces• Plan More Direct and Narrow Roadways • Replant Native Species Along Roadways and Parking Lots
as Environmental Species
1. Strategic Development
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Example of Strategic Development
• Development & land use
• Increase in impervious surfaces
• Loss of natural percolation filtration
• Increase in runoff velocity causes erosion
Solutions
•Decrease impervious surfaces
• Green roof
• Rain gardens
• Installing water absorbing plants around highways
Problems
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2. Wastewater Treatment Plants (WWTPs)
• WWTPs minimize environmental contamination from surface runoff, industrial, agriculture, & residential sources • Multiple WWTPs discharge into the PRV
http://www.epa.gov/nps/whatis.html
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2. Alexandria Sanitation Authority
• Tertiary treatment plant with UV & oxygen to effluent processes over 54 million gal/day (12 billion)
• Filters 4.3 million lbs of N & 746,000 lbs of P per year • Minimize algae blooms that feed on nitrogen and create
oxygen dead zones
• Use methane gas to heat and cool plant (780 homes annually)
http://www.alexsan.com/how_does_asa_clean_dirty_water.asp
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2. Wastewater Treatment Plants & the PRV
• Effluent from wastewater treatment plants is currently the most notably identified point-source contribution of endocrine disrupting contaminants in the Potomac River.
• Emerging contaminants in the Potomac include personal care products, pharmaceuticals and over-the-counter medications, agricultural pollution, animal feedlots, and industrial byproducts.
http://www.potomac.org/site/snapshot-watershed/index.php
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3. Changes in Culture
• End the “Zero-Sum Game” mindset• You can’t reach a “win-win” resolution if you’re not
looking for one
• Look at problems (and for solutions) holistically • Myopic understanding of problems encourages
simplistic (not simple) solutions that tend to be ill-suited to the complex reality... then no one wins
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3. Changes in Culture
• Enshrine the concept of the “Precautionary Principle” at the same level as that of the concept of “Progress”• Neither is bad and neither is the enemy of the
other; they must be used in a complimentary manner
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Conserve/Help/Protect Vulnerable Symbioses
•Better education for the offenders•Better enforcement of the laws•Strengthen environmental laws
3. Changes in Culture (through education)
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4. Changes in Regulatory Structure
• Recognize and prioritize Ecosystem Services
• Neglecting or taking for granted what nature provides tends to result in losing that value
• Assigning economic value is one way to handle this in a free-market system… this does not necessarily mean buying and selling
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4. Changes in Regulatory Structure• Require “Cradle-to-Grave” and/or “Cradle-to-
Cradle” analysis for products and processes• Often the most damaging things we do are
accidental/incidental, related to an aspect or feature we overlooked or don’t understand; only by eliminating those blind-spots can we make decisions that can even ATTEMPT to be mutualistic
• Acknowledge that previous failures to understand such complex systems could presage future failures• “Measure twice, cut once” – learn from past mistakes
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B. Bioremediation
• How can we utilize local species and the relationships between these species to help monitor, conserve and rejuvenate the Potomac River Valley for future generations?
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1. Bioindicators
• Use mycorrhizae and other mutualisms as bioindicators of ecological system health
• Foraminifers as bioindicators of coral reefs• Zooxanthellate and foraminifers have similar water-
quality requirements• Short life span provides differentiation between long-
term water quality decline and episodic events• Small and abundant
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Symbioses as Bioindicators
• Symbiosis degradation can be a measure of impact
• Monitoring the health of these relationships as a measure of ecosystem health
• Symbiosis success can be a standard to achieve
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2. Bioremediation using symbioses
• Many mutualisms affect pollution
complex systems in wetlands filter water by:• Removing metals, nutrients, silt, etc.• Promoting new wetlands growth and biodiversity
which could help decrease pollutant levels
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Bioremediation using mycorrhizae
• Mycorrhizae bioremediate through bacterial recruitment and improving soil conditions
• Bacteria that are recruited can use PAHs as a source of carbon and thus break them down and detoxify them
• Leeks (wild ramps in the PRV) could help detoxify fossil fuel emissions from major highways
(Leyval & Binet, 1998)
(Bouchez et. al, 1995)
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Soil Stabilization and Nutrient Recruitment by Mycorrhizae• Andersson et. al (1994) found that Paxillus
involutus, a mycelium associated with Picea abies (Norway spruce) and (Betula pendula) silver birch increased nitrate assimilation
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Bioremediation by Native Species
Virginia Cooperative Fish and Wildlife Research Unit 2010
Mussels
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Six Hours Later
• One mussel can filter ~0.5 gallon/hr
Virginia Cooperative Fish and Wildlife Research Unit 2010
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More Solutions/Symbioses
• Development of an intelligent robot to:• To wander through the PRV waters
• To seek-out pollutants
• To process and eliminate pollutants
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Conclusions• Stressors play a defining role in symbioses
• Environmental education and legislation is essential for the protection of our ecosystems
• Bioremediation is a powerful tool in protecting and cleaning up ecosystems
• Symbioses can play an integral role in the process of bioremediation
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Floor is Open for Questions
Where Innovation Is Tradition
Resources• Adamson, N. (2009, April 18). Native Bee Pollinators for Crops. Retrieved April 16, 2010, from
http://www.slideshare.net/sdroege/native-bee-pollinators-for-crops• Andersson, S., Arnebrant, K., & Söderström, B. (1994). Growth and Assimilation of NH4 + and NO3 -
by Paxillus involutus in Association with Betula pendula and Picea abies as Affected by Substrate pH. New Phytologist, 128(4), 629-637.
• Appleton, B., Spivey, A., & French, S. (2009). Virginia Cut Holly Production: Holly Pollination and Honey Bees – Virginia Cooperative Extension. Retrieved March 23, 2010, from
http://pubs.ext.vt.edu/430/430-468/430-468.html• Booth, D. M., and Heck, K.L. (2009). Effects of the American oyster Crassostrea virginica on growth
rates of the seagrass Halodule wrightii, Marine Ecology Progress Series, Vol 389: 117-126.• Bouchez, M., Blanchet, D., and Vandercasteele, J.P. (1995). “Degradation of polycyclic aromatic
hydrocarbons by pure strains and by defined strain associations: inhibition phenomena and cometabolism.” Applied Microbiology and Biotechnology. 43.1: 156-164.
• Brown, B. E. (1997). Coral bleaching: causes and consequences. Coral Reefs, 16, S129-S138. Development - Bay Pressures - Chesapeake Bay Program. Retrieved March 18, 2010, from http://www.chesapeakebay.net/developmentpressure.aspx?menuitem=19514
• Cloern, J. E. (2001). Our evolving conceptual model of the coastal eutrophication problem, Marine Ecology Progress Series, Vol 210: 223-253.
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Resources• Fulford, R. S., et al. (2007). Effects of oyster population restoration strategies on phytoplankton
biomass in Chesapeake Bay: a flexible modeling approach, Marine Ecology Progress Series, Vol. 336: 43-61.
• Goldman, E. (2004). Recovering Resilience: Can Restoration Bring Back the Bay’s Buffers? Chesapeake Quarterly, Vol. 3, No. 3.
• Heithaus, R., & Humes, M. (2003). Variation in communities of seed-dispersing ants in habitats with different disturbance in Knox County, Ohio. The Ohio Journal of Science, 103(4), 89–97.
• Helfrich,Loui and et al. Help save America's Pearly Mussels. Virginia Cooperative Extension. At:http://pubs.ext.vt.edu/420/420-014/420-014.html
• Hughes, A. R., et al. (2009). Associations of concern: declining seagrasses and threatened dependent species, Frontiers of Ecology and the Environment, 7(5): 242-245.
• Jackson, J.B.C., et al. (2001). Historical overfishing and the recent collapse of coastal ecosystems, Science: July 27, 2001, p. 629.
• Kemp, W.M., et al. (2005). Eutrophication of Chesapeake Bay: historical trends and ecological interactions, Marine Ecology Progress Series, Vol. 303: 1-29.
• Kneeland, S. and Rhymer, J. (2008). Determination of fish host use by wild populations of rare freshwater mussels using a molecular identification key toidentify glochidia. Journal of the North American Benthological Society 27(1):150-160.
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Resources• Lenihan, H. S., and Peterson, C.H. (1998). How habitat degradation through fishery disturbance
enhances impacts of hypoxia on oyster reefs, Ecological Applications, 8(1).• Leyval, C., and P. Binet. (1998). "Effect of polyaromatic hydrocarbons in soil on arbuscular
mycorrhizal plants." Journal of Environmental Quality 27.2: 402-7. Applied Science Full Text. Web. 13 Feb. 2010.
• Liu, F., Toda, H., & Haibara, K. (2001). Effects of clear-cutting and burning on characteristics of nitrogen mineralization and microbes in the forest soil of a Pinus massoniana plantation in Southern China. Ecological Research, 16(3), 531-542.
• Lowe, Brian and Provenzano,Anthony. (1990). Survival and reproduction of Palaemontes paludosus in saline water. Journal of Crustacean Biology, 10(4):639-647.
• Margulis, L., and R. Fester (Eds.). (1991). Symbiosis as a source of evolutionary innovation: speciation and morphogenesis. MIT Press, Cambridge Mass. Retrieved from:http://books.google.com/books?id=3sKzeiHUIUQC&printsec=frontcover#v=o
nepage&q=&f=false• Morgan II, R., Rasin, J. and Noe, L. Sediment Effects on Eggs and Larvae of Striped Bass and White
Perch. Appalachian Environmental Laboratory, Center for Environmental and Estuarine Studies, University of Maryland.
• Pant, HK and Reddy, KR. (2001). Phosphorus sorption characteristics of estuarine sediments under different redox conditions." Journal of Environmental Quality 30:1474-1480.
• Sanford, M. (1998). Pollination, The Forgotten Agricultural Input. Proceedings of the Florida Conference and Trade Show, 45-47.
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Resources• Stachowicz, J. J. (2001). Mutualism, Facilitation, and the Structure of Ecological
Communities. BioScience, 51(3), 235. • Stamets, P. (2005). Mycelium running : how mushrooms can help save the world. Ten
Speed Press, Berkeley Calif. Retrieved from: http://books.google.com/books?id=NPI8_omzvsC&dq=mycelium+running&printsec=frontcover&source=bn&hl=en&ei=2PN5S93XOZCqNpuayLQH&sa=X&oi=book_result&ct=result&resnu m=6&ved=0CCIQ6AEwBQ#v=onepage&q=&f=false
• Villella, Rita. Impact of aluminum-laden sediment discharge on viability of native freshwater mussels in the Potomac River; Detailed project information for study plan 02098. At: www.lsc.usgs.gov/SPN.asp?StudyPlanNum=02098
• Virginia Cooperative Fish and Wildlife Research Unit. 2010. U.S. Fish and Wildlife Service, Department of Fisheries and Wildlife Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia.
• Winegar, Deane. Longstreet highroad guide to the Chesapeake Bay. Retrieved from: www.sherpaguides.com/chesapeake_bay/natural_history/
• Zahran, H. H. (1999). Rhizobium-Legume Symbiosis and Nitrogen Fixation under Severe Conditions and in an Arid Climate. Microbiol. Mol. Biol. Rev., 63(4), 968-989.