Session IV Marine Plastic Pollution: From sources to

Session IV
Marine Plastic Pollution: From sources to solutions
SVENJA BEILFUß1* and JOHANNA WIEDLING2
1
*BIOCONSULT Schuchardt & Scholle GbR, Reeder-Bischoff-Straße 54, 28757 Bremen,
Germany
2
Leibniz Center for Tropical Marine Ecology (ZMT) GmbH, Fahrenheitsr. 6, 28359 Bremen,
Germany
Plastic accounts for around 70% of the marine debris and since synthetic material has a
long decomposition time it poses a great risk for the marine environment. Physical,
chemical and biological degradation lead to smaller plastic particles. These microplastics
also accumulate in the marine environment bringing about yet unknown threads. Plastic
pollution is a complex subject causing tremendous ecological, economical and social
problems. Young researchers are invited to contribute with their work on plastic in the
marine environment and its associated problems to solve the gaps in our knowledge. We
would also like to encourage the presentation of management recommendations and
strategies on how to reduce and monitor marine plastic pollution.
Contents
Talks [time slot]
Werner [13.9.2013; 8.30 am] INVITED SPEAKER
Neumann et al. [13.9.2013; 8.45 am]
Evaluation of marine litter transport simulations in the German Bight from monitoring
perspective
Löder and Gerdts [13.9.2013; 9.00 am]
FT-IR analysis for monitoring marine microplastics
Mildenberger et al. [13.9.2013; 9.15 am]
Fouling and Degradation of Plastic in the Marine Environment
Nerheim et al. [13.9.2013; 9.30 am]
Diversity and Abundance of Plastic-Associated Marine Microorganisms
Haemer et al. [13.9.2013; 9.45 am]
Uptake, Transport and Deposition of Microplastics in Marine Isopods
Session IV Marine Plastic Pollution: From Sources to Solutions
1
Evaluation of marine litter transport simulations in the
German Bight from monitoring perspective
DANIEL NEUMANN1*, ULRICH CALLIES1, MICHAEL MATTHIES2, Marcus
Schulz2
1
Institute of Coastal Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Str. 1, 21502
Geesthacht, Germany
2
Institute of Environmental Systems Research, University of Osnabrück, Barbarastr. 12,
49076 Osnabrück, Germany
*corresponding author: [email protected]
Key words: marine debris, Lagrangian transport modeling, wind drift, intra-annual
variation, source-receptor relationship
Ensemble drift simulations were performed with an offline Lagrangian transport
model. Passive tracers, partly affected by additional wind drift, represented submerged
and atop floating marine litter items. Over 9 years every 28 hours particles were injected in
the German Bight and drifted 90 days forward and backward in time.
Forward simulations were evaluated with respect to real coastal monitoring sites.
Modeled time series of litter abundance at Sylt clearly show seasonal variations with
maxima in autumn. This is caused by varying distance of coast-parallel currents to the
coast of Schleswig-Holstein. Single backward simulations show a wide spectrum of
possible source regions. However, temporally averaged backward simulations started from
East Frisian Islands suggest primarily westerly located source regions. Particles started
from the North Frisian Islands originated from the Elbe estuary or also from the west. In
forward and backward simulations, additional wind has a considerable influence on the
particle drift: Particle abundance and residence times at coasts are increased. At the same
time residence times at the open sea decrease considerably. In time series of wind drifted
items, seasonal patterns are less developed than in those of not wind drifted ones and
noise is higher.
Results clearly show that seasonal variability in beach litter monitoring data partly
results from natural variability in ocean currents and winds. Combining litter monitoring
data with backward simulations seems reasonable. The parameterization of the vertical
position of litter items in the water column by scaling the wind drift is uncertain and adds
considerable uncertainty to model results.
Session IV Marine Plastic Pollution: From Sources to Solutions
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FT-IR analysis for monitoring marine microplastics
MARTIN G. J. LÖDER1* AND GUNNAR GERDTS1
1
Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Biologische
Anstalt Helgoland, Kurpromenade 201, 27498 Helgoland
*corresponding author: [email protected]
Key words: FT-IR spectroscopy, marine microplastics, monitoring
Persistent plastics are hardly degraded and accumulate in the marine environment.
Their fragmentation leads to an increasing amount of small plastic particles, so-called
microplastics. Due to their size, these have the potential of entering marine food webs.
For a reliable evaluation and an assessment of food web effects, a detailed quantitative
and qualitative monitoring of microplastics in the marine environment is highly required
and thus stipulated within the framework of the Marine Strategy Framework Directive
(MSFD). Due to the sampling procedures and the sample analyses currently used, the
scarce data on microplastics concentrations are mostly biased towards larger particles.
Therefore, reliable data on concentrations of the total size spectrum of microplastics in
marine systems and especially in German coastal waters are still lacking. Furthermore, the
polymer origin of potential microplastic particles needs to be verified during analysis.
Fourier Transform infrared (FT-IR) spectroscopy offers the possibility of proper
identification of plastic particles in environmental samples. However, standard FT-IR
spectroscopy still requires time- and labour-consuming pre-sorting of particles by hand.
Hence, small or less abundant microplastics are potentially overlooked. A highly promising
FT-IR extension (FT-IR Imaging) allows for detailed and unbiased high throughput analysis
of total microplastics in a given sample without prior pre-sorting by hand. Thus the project
MICROPLAST aims on (1) the development/optimisation of appropriate methods for the
extraction of microplastic particles from complex matrices (e.g. sediment, plankton, tissue),
(2) the evaluation of FT-IR imaging for the analysis of microplastics and the development
of procedures for its routine application, (3) the first-time production of valid data on the
pollution of the pelagic and benthic zone with microplastic particles in German coastal
waters.
Session IV Marine Plastic Pollution: From Sources to Solutions
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Fouling and Degradation of Plastic in the Marine
Environment
TOBIAS MILDENBERGER1, ANDREAS EICH2, JOHANNA WIEDLING3,
CHRISTIAN LAFORSCH1 AND MIRIAM WEBER*,4,5
1
University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
2
University of Bremen, Bibliothekstraße 1, 28359 Bremen, Germany
3
Leibniz Centre for Marine Tropical Ecology, Fahrenheitsstraße 6, 28359 Bremen,
Germany
4
Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359 Bremen, Germany
5
HYDRA Institute Field Station Centro Marino Elba, Via del Forno 80, Fetovaia, I-57034
Campo nell’Elba (LI), Italy
*corresponding author: [email protected]
Key words: biodegradable plastic, marine pollution, biofouling, biodegradation
Increasing amounts of plastic accumulate in the oceans and harmful consequences
for marine ecosystems have already been shown. Hence, knowledge on biodegradation in
marine environments is a prerequisite to foster management strategies in the future. Since
plastic debris serves as substrate for microorganisms, this biofilm may result in
biodegradation of the polymer. However, little is known about the composition of these
biofilms and how it affects the degradation of plastic. This pilot-study aimed investigating
microbial biofouling of biodegradable and conventional plastic bags.
We exposed conventional and biodegradable plastic to the Mediterranean Sea in
the Bay of Fetovaia, Elba, Italy. Additionally a mesocosm experiment with controlled
parameters was performed. We investigated the microbial settlement in the first 5 weeks
after plastic bag pieces had reached the ocean. Therefore the amount of biofilm and
diatoms (including classification) were measured. The total microbial activity was
determined measuring oxygen consumption/production rates and oxygen profiles
throughout the biofilm. For estimating degradation, tensile properties were investigated.
The tensile strength of both plastic types declined indicating biodegradation in our
experiments. No differences could be observed between both plastic types. The settlement
of microorganisms on the plastic surface increased with time on both plastic types. We
assume that the growing biofilm changes the microenvironment on the plastic surface
compared to the surrounding water and thereby its degradation. The net consumption of
oxygen driven by microorganisms was higher than the oxygen production. This indicates
that the degradation takes place under anoxic conditions.
A better understanding of plastic degradation in the marine environment will help solving
the global problem of plastic in the oceans.
Results clearly show that seasonal variability in beach litter monitoring data partly
results from natural variability in ocean currents and winds. Combining litter monitoring
data with backward simulations seems reasonable. The parameterization of the vertical
position of litter items in the water column by scaling the wind drift is uncertain and adds
considerable uncertainty to model results.
Session IV Marine Plastic Pollution: From Sources to Solutions
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Diversity and Abundance of Plastic-Associated Marine
Microorganisms
MAGNUS S. NERHEIM1,2* with HENRY S. CARSON1, KATHERINE
CARROLL1, MARCUS ERIKSEN3 and with GUNNAR BRATBAK2, SANDRA
I. SCHÖTTNER2
1
Marine Science Department, University of Hawai ʻi at Hilo, Hilo, Hawai ʻi USA
2
Department of Biology, University of Bergen, Bergen, Norway
3
Five Gyres Institute, Los Angeles, California USA
*Corresponding author: [email protected]
Key words: Marine debris, Plastic, Microorganisms, Bacteria, Diatoms
Several key-processes regarding the fate and impact of plastic pollution in the
ocean are likely mediated by microorganisms, including degradation, buoyancy, chemical
adsorption, and colonization or ingestion by larger organisms.
In a study on marine debris from the North Pacific Gyre, we related the abundance
and diversity of plastic-associated microorganisms to a variety of physical and biological
factors, including location, temperature, salinity, plankton abundance, plastic
concentration, item size, surface roughness, and polymer type. Plastic fragments and
pellets (<1 cm diameter) were collected from surface waters along a transect through the
eastern part of the gyre using manta trawls and examined for microorganisms using
Scanning Electron Microscopy (SEM). The plastic-associated microbial community was
dominated by rod-shaped bacteria (mean 1,664±247 cells mm -2) and pennate diatoms
(1,097±154 mm-2), but also included coccoid bacteria (169±39 mm -2), centric diatoms (9±6
mm-2), and rare instances of dinoflagellates, coccolithophores, and radiolarians. Bacterial
abundance was patchily distributed, but increased significantly on foamed polystyrene
compared to polyethylene or polypropylene. Diatom abundance increased in the transect
center, along with increasing plastic concentration, and was higher on items with rough
surfaces. Morphotype richness increased slightly on larger items, and a biogeographic
transition occurred between pennate diatoms as the transect moved northeast. Overall,
these results clearly document the presence of heterogeneous biofilm communities on
marine plastic debris, and suggest that investigating the effects of plastic-microbe
associations could be important to understanding the consequences of plastic pollution in
the ocean.
Further insights into plastic-associated marine biofilms will be gained from an in-situ
experiment in a Norwegian coastal ecosystem. Based on DNA and whole-cell analyses,
such as Automated Ribosomal Intergenic Spacer Analysis, Flow Cytometry, Fluorescence
In-situ Hybridization and SEM, microbial diversity and abundance will be related to plastic
type, location in the water column (surface, sub-surface, sediment-water interface), and
concentration of plastic-associated organic pollutants.
Session IV Marine Plastic Pollution: From Sources to Solutions
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Uptake, Transport and Deposition of Microplastics
in Marine Isopods
JULIA HAEMER1,2*, LARS GUTOW1 AND REINHARD SABOROWSKI1
1
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research – Functional
Ecology - Am Handelshafen 12, 27570 Bremerhaven
2
Ruhr-University Bochum - Department for Animal Ecology, Evolution and Biodiversity Universitätsstraße 150, 44780 Bochum
*corresponding author: [email protected]
Key words: microplastics, invertebrates, isopods
Plastics are synthetic organic polymers. Its durable, light-weight and cheap
properties made plastics become an integral part of our daily life. The annual production
accounts for > 265 Mt whereof an estimated amount of 10% ends up in our oceans as
“marine litter”.
Harmful effects of plastics have been documented for more than 267 marine animal
species. Particularly birds, mammals and reptiles die after ingestion of plastic fragments or
entanglement in plastic ropes. Smaller particles of less than 5 mm originating e.g. from
fragmentation or hygienic products are denoted as microplastics. These particles can be
ingested by a wide range of organism and thus, are recognized as a severe environmental
problem.
In order to estimate possible effects of microplastics on aquatic crustaceans we
studied the uptake of fluorescent microplastic fibres, fragments and beads and the
transport and deposition of the particles in the digestive tract of the marine isopod Idotea
emarginata. Microplastics were offered in agar-based algal food to the animals. In choicefeeding assays I. emarginata non-selectively ingested food pieces supplemented with
microplastics. Ingested microplastics were traced through the intestines using histological
methods. Fluorescent particles occurred in high numbers in the stomach and in the gut
while the tubules of the midgut gland were void of microplastics. Apparently, the unique
anatomy of the stomach with the fine-meshed proventricular filter press efficiently prevents
the passage of microplastics into the midgut glands. Effects of long-term exposure to
ingested microplastics on the isopod fitness were assessed in biotests. Microscopic fibres
and fragments had minor effects on the size increment, moult cycle and ingestion rates of
I. emarginata. However, our results indicate that daily doses of 10 µm microbeads
prolonged the intermoult period. Additionally, the isopods had lower ingestion rates for food
containing microbeads.
Session IV Marine Plastic Pollution: From Sources to Solutions
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