The methodology of HOTSPOT includes the use of existing data, sampling of new data, laboratory experiments, modelling and interviews and focus group discussions.
Pollutants to be investigated
HOTSPOT has a focus on the environmental effects of heavy metals (V, Ni, Pb, Cu, Cd, Zn, Hg, Cr, Ba), oil compounds, marine litter (including micro-plastics) and ‘emerging’ contaminants (e.g., pharmaceuticals), in combination with the stress caused by increasing sea surface temperature.
Maritime pollution in the coastal areas interacts with the land-based pollutants such as mining, industrial and municipal waste, and increasing sea surface temperature will influence the way organisms respond to pollutants. Maritime pollutants will thus need to be considered in the context with land-based pollution and climate change.
Seasonal sampling campaigns
The HOTSPOT project is building-up a capacity for the monitoring of coastal waters, including measurements of hydrography, nutrients, phytoplankton and zooplankton with sampling conducted from local fishing boats.
These monthly sampling campaigns are complemented by more intensive transect studies from Elmina fishing harbor towards the open sea, to investigate the types and concentrations of pollutants, and their spread and effect in the marine ecosystem. These field studies will provide the baseline understanding of the marine environment in the coast of Ghana.
In addition, we will investigate the bioaccumulation of contaminants in plankton and fish.
Laboratory experiments
To investigate the cumulative effects of stressors and the mechanisms behind species responses, we will conduct laboratory experiments measuring mortality, feeding, respiration and reproduction of key zooplankton species in a relevant range of concentrations of contaminants and their mixtures, and including 2-3 different temperatures. The contaminants to be investigated will be chosen based on the analysis of contaminant sources.
The bottle incubations with single species will be up-scaled to population and community levels. This will be done both using a mechanistic model and experimentally, in so-called mesocosms experiments. Mesocosms experiments will be conducted in land-based containers, with an enclosed natural plankton community manipulated by contaminants.
Modelling
Simple statistical models and individual-based models will be used for synthetizing the data, and can be included as modules in the more complex ecosystem models. In addition, data and insights obtained through the project will be synthetized in a conceptual model which will help to focus management actions to particularly sensitive seasons and areas, and will form a dissemination tool to authorities.
Socio-economic studies
The socio-economic studies in HOTSPOT will include key informant interviews with community elders, traditional fishery governance institutions, and relevant governmental organizations to better understand the history of fishing communities and decision-making processes that influence small-scale fishing.
In addition, focus group discussions with older male, older female and mixed gender youth will be carried out to explore the challenges each group is facing in respect to livelihood and migration strategies.
Furthermore, in-depth interviews with males and females of all ages, whose livelihoods depend on small-scale fishing, will be conducted.