A novel approach to measure nutrient fluxes in permeable sediments

Lead Research Organisation: NATIONAL OCEANOGRAPHY CENTRE
Department Name: Science and Technology

Abstract

Around the globe, the coastal ocean is of immense importance, as it provides critical functions for the environment, society and economy. Sediments play a fundamental role in the wellbeing of the coastal ecosystems as they are able to convert, store and release chemical compounds that affect and control life. For example, sediments are a major sink for oxygen, but it is also suggested that coastal sediments are very important in the recycling of nutrients, a process that controls primary production, but also plays a role in the production of algal blooms or low oxygen conditions in coastal waters. However, due to the specific geophysical characteristics of many coastal sediments (i.e. they often are composed of loose sand grains), measurements that quantify the nutrient exchange between the sediments and water column are very difficult and hence the recycling capacity of nutrients in these sandy sediments is not well quantified, even though it is likely to be highly important.

Here we propose a proof-of-concept study to develop a new capability to quantify the exchanges of nutrients between different types of sandy sediments and the water column. To achieve this, we will adapt a well-known technique to measure oxygen exchange between sediments and the water column (i.e. so called benthic chambers). We will equip these flux exchange recorders with novel miniaturized sensors that autonomously can measure nutrient concentrations in an enclosed volume of water. We will also integrate them with sensors measuring water flow and sediment bed properties. We first will verify the functioning of the new approach in the laboratory and then demonstrate it in a real-world scenario. For this we have chosen an area along the UK South Coast, that is known for high nutrient levels, caused by agricultural discharges, wastewater, urban runoff and sewer overflows, and where high nutrient inputs historically already led to algal blooms and low oxygen concentrations in the water column. This novel capacity can produce knowledge that is urgently needed to sustain a healthy environment and manage our natural resources and on the longer-term can be adapted to measure other geochemical species, e.g. other pollutants and in different environments.

Publications

10 25 50
 
Description We were able to develop a new method to autonomously measure nutrient exchanges between the water column and the sediment in coastal areas what up to now was difficult. This new method now enables us to understand the nutrient loading in this highly dynamic environment and can be applied in coastal/ sandy areas worldwide.
Exploitation Route Once published this data will be useful for environmental impact assessment by governmental and non-governmental organization and other researchers.
Sectors Communities and Social Services/Policy

Environment

 
Description Engagment with local community
Geographic Reach Local/Municipal/Regional 
Policy Influence Type Participation in a guidance/advisory committee
 
Description Sandman (A novel technology to understand environmental changes in marine sediments)
Amount £1,489,823 (GBP)
Funding ID MR/X035387/1 
Organisation United Kingdom Research and Innovation 
Sector Public
Country United Kingdom
Start 05/2024 
End 05/2028
 
Title Benthic chamber for nutrient fluxes 
Description The new method is a benthic camber that now can also autonomously measure the exchange of nutrients between the sediment and the water column in coastal sediments 
Type Of Material Technology assay or reagent 
Year Produced 2023 
Provided To Others? No  
Impact Too early to say 
 
Description CEFAS collaboration 
Organisation Centre For Environment, Fisheries And Aquaculture Science
Country United Kingdom 
Sector Public 
PI Contribution We applied to for the PhD fellowship, provide the technology and team expertise.
Collaborator Contribution A phD student ship has been granted by INSPIRE on this topic and CEFAS co-sponsered the PhD student and gives access to research data, facilities and shiptime
Impact no outputs yet
Start Year 2023
 
Description AWI field station advisory board 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Member of the advisory board of field station infrastrucure of the Alfred Wegener Institute to give advise on how improve their facility and engage better with the international community
Year(s) Of Engagement Activity 2023,2024
 
Description Engagment with local community 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Public/other audiences
Results and Impact Discussion with the local public and scientists from other fields about the water quality of the River Itchen, which is important for the area and also a unique environment (chalk river). The intended purpose was to find and advise on the best scientific approach to test the local water quality.
Year(s) Of Engagement Activity 2023,2024
 
Description Video and press release 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Film team participating in field work and making short movie about the importance of project. Distrubution through different NOC channels.
Year(s) Of Engagement Activity 2023