Kaylee Smit

PHD candidate
Kaylee Smit


 

Using a trait-based approach to identify indicators of ecosystem condition using subtidal rocky reefs in the Natal bioregion of South Africa.

An ecosystem-based approach to Marine Spatial planning is predicated on the principle of achieving good ecological status for oceans. However, in situ measurements of ecosystem condition at broad scales remains a global knowledge gap as does a better understanding of the cumulative impact of human uses on ocean ecosystems. Most important is the absence of a standardised data-derived approach to measure ecosystem condition. This poses challenges for national assessments, for example, the National Biodiversity Assessments (NBAs) and environmental monitoring requirements of national government. The NBA currently relies on a proxy of cumulative human impacts to infer good, fair or poor ecosystem condition at a national scale, creating the need for fine-scale ecosystem-based condition assessments using ecological data. To address these needs, a trait-based approach was tested to identify functional indicators of rocky reef condition using fish and invertebrate community data collected by remote imagery methods. The proportion of traits in a community and functional indicators like functional richness, diversity and RAO’s quadratic entropy reflected changes in ecosystem processes and how well the community functions, regardless of the type of species that occur. The functional structure of the Pondoland marine protected area provided reference conditions to illustrate the impacts of cumulative human pressures on ecosystem function. This projected thus identifies possible indicators that can be used to measure ecosystem condition of rocky reefs, and which can be applied across bioregions and broad habitat types. Measuring ecosystem condition will inform national reporting and aid with mitigating further degradation from cumulative human impacts.

Registered at: Nelson Mandela University (NMU)

Supervisor: Amanda Lombard (NMU)
Co-supervisors: Dr Anthony Bernard (SAIAB); Dr Kerry Sink (SANBI)