This work package will assess the nutrient sources of major inputs from land, sea-ice and oceans and provide information on the key transformation processes that determine their eventual inputs to open-ocean ecosystems. Field observations and laboratory analyses will be used alongside satellite data, historical data (both observational and modelled) and projected changes in inputs, to gain insight into future impacts on supply to marine ecosystems.
We aim to answer the following questions throughout the project:
- What are the dominant processes that modify isotopic signatures, nutrient forms and lability between sources and the receiving marine ecosystem?
- How do physicochemical and biological processes influence the behaviours of organic and inorganic constituents?
- What conditions promote nutrient sorption-desorption from suspended sediments?
- Exactly how much microbial and photolytic production/consumption of dissolved organic matter and other nutrient pools is taking place in local freshwater autotrophic communities?
We will address the following main research question: What physical, chemical and biological processes modify elemental balance en route from source to polar ocean ecosystem, and what are their sensitivities to climate change?
To do this, our work will be split into the following sub tasks:
WP1.1 Nutrients and Tracers
How are nutrients supplied from land?
WP1.2 Source to Sea Processes
How are nutrient concentrations and ratios impacted by physical, chemical and biological processes downstream?
WP1.3 Mixing and tracking
How does mixing between different waters influence nutrients?
WP1.4 Sensitivity of large scale fluxes
How sensitive is the supply of nutrients to future climate change?