Environmental Health

Healthy, unpolluted seas are required to support food provision, recreation and other marine services such as waste remediation. We are developing novel models to track the fate and biological impact of microplastics, in particular looking at interference to zooplankton feeding and sinking of organic waste. Our models also track the development of environmental conditions that can promote Harmful Algal Blooms (HABs) and support the EU Marine Directive by simulating  indicators of Good Environmental Status.
 

Marine microplastics

Microplastics are small plastic particles measuring between a few microns and several millimeters in size. The term includes plastic pellets or beads that are manufactured to be of a small size, and microplastics that are formed following the fragmentation of larger plastic items, such as plastic bags, bottles or polystyrene sheets. Microplastics may enter the marine environment directly via rivers and sewage outflows, or be formed at sea. In the marine environment they may persist for hundreds or thousands of years due to the slow rate at which they breakdown. Microplastics are a cause for widespread environmental and economic concern. Their small size makes them easily ingested by a wide range or marine organisms, including fish and large zooplankton.

PML is at the forefront of research on microplastics. We use models to track the movement of microplastics in UK coastal waters in order to better understand the factors controlling their transport and distribution (see animation). In collaboration with the University of Exeter, we are also building models to help increase our understanding of the consequences of microplastic exposure or ingestion for marine life.

Further information

Please contact: James Clark

Related publications

  • Cole M, Lindeque P, Fileman E, Halsband C, Goodhead R, Moger J and Galloway TS. 2001. Microplastic Ingestion by Zooplankton Environmental Science & Technology, 47, 6646-6655, doi:10.1021/es400663f
  • Cole M, Lindeque P, Halsband C and Galloway T. 2011. Microplastics as contaminants in the marine environment: A review Marine Pollution Bulletin, 2011, 62, 2588-2597, doi:10.1016/j.marpolbul.2011.09.025
This animation shows the probable location of buoyant plastic particles following their release into Plymouth Sound. The animation covers a time perdiod of 48 hours with blue triangles showing the location of field sampling sites.

This animation shows the probable location of buoyant plastic particles following their release into Plymouth Sound. The animation covers a time period of 48 hours with blue triangles showing the location of field sampling sites.

 
 

Harmful Algal Blooms (HABs)

Harmful algal blooms have been increasing in frequency, magnitude, and duration worldwide.  This rapid growth of algae can kill fish, contaminate seafood with toxins, form unsightly scums or detrimentally alter ecosystem function. HABs develop when particular environmental conditions (e.g. the right temperature, salinity, nutrients) occur at the same time. They can be harmful to marine species as well as humans (from simple nuisance to permanent brain damage), causing serious damage to economic activities like fishery, aquaculture and tourism. Although HABs can occur naturally in a pristine environment, human activities and climate change can increase the risk of HAB events.

The ERSEM model, in combination with a suitable hydrodynamic model such as NEMO or FVCOM, is ideally suited to predict the potential for changed HAB distributions, as it combines an ecosystem approach with short- and long-term environmental change drivers. For example, by using a bioclimatic modelling approach in the North West European shelf, the potential effects of nutrient loading and climate change on blooms of the dinoflagelltae Prorocentrum sp. can be explored (see associated animation).

Further information

Please contact: Yuri Artioli

Related publications

  • Glibert PM, Allen JI, Artioli Y, Beusen A, Bouwman L, Harle J, Holmes R and Holt J. 2014. Vulnerability of coastal ecosystems to changes in harmful algal bloom distribution in response to climate change: projections based on model analysis. Global Change Biology 20:3845-3858, dio: 10.1111/gcb.12662
The figure shows the risk of the right conditions for groups of HABs in the North Sea in the present climate and at the end of the century.

The figure shows the risk of the right conditions for groups of HABs in the North Sea in the present climate and at the end of the century.

 
 

Indicators for Good Environmental Status

One of the key objectives of the European Union’s Marine Strategy Framework Directive is to achieve Good Environmental Status (GES) of EU marine waters by 2020. GES is defined as “The environmental status of marine waters where these provide ecologically diverse and dynamic oceans and seas which are clean, healthy and productive”.

Models can support marine policy by assessing the state of marine ecosystems and its response to natural and human induced pressures by looking at biogeochemical indicators. Such indicators drive, or are driven by, ecosystem dynamics such as the concentration of nutrients, chlorophyll, and dissolved oxygen. We can simulate, predict and provide scenarios of biogeochemical indicators to support the management of marine health and the implementation of international legislation like the European Marine Strategy Framework Directive.

Further information

Please contact: Stefano Ciavatta

Related projects

Marine Ecosystem Dynamis and Indicators of North Africa) MEDINA
Vectors of Change in Oceans and Seas Marine Life, Impact on Economic Sectors (VECTORS)

Related publications

  • Picart SS, Allen JI, Butensch√∂n M, Artioli Y, de Mora L, Wakelin S, & Holt J (2014). What can ecosystem models tell us about the risk of eutrophication in the North Sea? Climatic Change, 1-15. DOI 10.1007/s10584-014-1071-x
Orange shows areas vulnerable to oxygen deficiency.

Orange shows areas vulnerable to oxygen deficiency.