Toward a Harmonized Approach for Monitoring of Riverine Floating Macro Litter Inputs to the Marine Environment

A high percentage of the litter entering the marine environment is assumed to come from land-based sources, but freshwater litter inputs have not been quantified. The lack of data and knowledge on fluxes of riverine litter to the sea, i.e. quantities and sources, hinders implementation of appropriate environmental regulations and mitigation measures. Estimations of riverine litter inputs require a consistent and harmonized approach to gather comparable data. The visual observation of floating litter on rivers has been selected as a simple and robust methodology for litter monitoring. A collaborative network of 32 institutions has been set-up for large spatial coverage. Currently 54 rivers are being observed regularly. A tablet computer application has been developed for the monitoring of floating macro litter (> 2.5 cm) to harmonize the visual observations. The application allows recording of the observed items, their size and geo-position data during monitoring sessions. A common agreed list of litter items and size ranges is used, providing a common harmonized approach for data collection and reporting.

[1]  Julia Reisser,et al.  Plastic Pollution in the World's Oceans: More than 5 Trillion Plastic Pieces Weighing over 250,000 Tons Afloat at Sea , 2014, PloS one.

[2]  Other,et al.  UNEP/IOC guidelines on survey and monitoring of marine litter , 2009 .

[3]  F. Galgani,et al.  Global Distribution, Composition and Abundance of Marine Litter , 2015 .

[4]  Sven E. Kerwath,et al.  Observer bias and detection probability in underwater visual census of fish assemblages measured with independent double-observers , 2013 .

[5]  Giuseppe Suaria,et al.  Floating debris in the Mediterranean Sea. , 2014, Marine pollution bulletin.

[6]  Michael Jasny,et al.  A critique of the UK's JNCC seismic survey guidelines for minimising acoustic disturbance to marine mammals: best practise? , 2009, Marine pollution bulletin.

[7]  Richard C. Thompson,et al.  Accumulation and fragmentation of plastic debris in global environments , 2009, Philosophical Transactions of the Royal Society B: Biological Sciences.

[8]  Richard C. Thompson,et al.  Sources, fate and effects of microplastics in the environment: a global assessment , 2015 .

[9]  C. Laforsch,et al.  Beyond the ocean : Contamination of freshwater ecosystems with (micro-) plastic particles , 2015 .

[10]  Martin Thiel,et al.  Floating marine debris in fjords, gulfs and channels of southern Chile. , 2009, Marine pollution bulletin.

[11]  Brian D. Smith,et al.  To See or Not to See: Investigating Detectability of Ganges River Dolphins Using a Combined Visual-Acoustic Survey , 2014, PloS one.

[12]  G. Hays,et al.  The broad-scale distribution of five jellyfish species across a temperate coastal environment , 2007, Hydrobiologia.

[13]  K. Hyrenbach,et al.  Habitat associations of floating debris and marine birds in the North East Pacific Ocean at coarse and meso spatial scales. , 2011, Marine pollution bulletin.

[14]  C. Wilcox,et al.  Plastic waste inputs from land into the ocean , 2015, Science.

[15]  P. Ryan.  A simple technique for counting marine debris at sea reveals steep litter gradients between the Straits of Malacca and the Bay of Bengal. , 2013, Marine pollution bulletin.

[16]  Lois A. Harwood,et al.  Factors influencing the Effectiveness of Marine Mammal Observers on Seismic Vessels, with examples from the Canadian Beaufort Sea Facteurs influençant l'efficacité des observateurs de mammifères marins sur les navires sismologiques, avec des exemples pour la mer de Beaufort canadienne , 2009 .