Aim Salt‐marsh foraminifera are widely used as robust sea‐level indicators. High‐resolution Holocene sea‐level reconstructions depend on the accurate characterization of modern foraminifera‐environment relationships representative of a study site. We investigate the relationship between modern foraminiferal assemblage distribution and key environmental variables, viz. elevation above land levelling datum (LLD), sediment grain size, organic content, pH and salinity. We hypothesize that the distribution of modern salt‐marsh foraminifera is primarily controlled by elevation above LLD. Location Knysna and Keiskamma estuaries along the southern coastline of South Africa. Methods Salt‐marsh surface sediment samples (n = 97) were collected along eight intertidal transects with corresponding environmental data (pH, salinity, organic content, sand, silt, clay and elevation). Multivariate ordination analysis (partial redundancy analysis; pRDA) was used to investigate the relationship between living foraminiferal assemblages and environmental controls, after accounting for spatial variability in community composition. Results The pRDA suggests that species composition varied spatially within estuaries, but was strongly influenced by elevation at Keiskamma (r = 0.63) and Knysna (r = −0.75). At Keiskamma, the main gradient in composition was also influenced by salinity (r = −0.63), in an equal and opposite manner to elevation. Composition at Keiskamma was influenced to a much lesser extent by sediment organic content (r = 0.20) and the clay fraction (r = −0.13). At Knysna, pH (r = 0.455) was a secondary determinant of composition, and sediment characteristics covaried with elevation. Main conclusion Elevation was found to be a key environmental variable controlling the distribution of salt‐marsh foraminifera at both estuaries, thereby validating the use of foraminifera as sea‐level indicators. Certain species were particularly sensitive to elevation changes and could thus serve as useful indicators of past sea‐level change. This is an important first step towards the development of high‐resolution sea‐level reconstructions for the South African coastline.

South Africa's extensive and topographically diverse coastline lends itself to interpreting and understanding sea-level fluctuations through a range of geomorphological and biological proxies. In this paper, we present a high-resolution record of sea-level change for the past ~1200 years derived from foraminiferal analysis of a salt-marsh peat sequence at Kariega Estuary, South Africa. A 0.94-m salt-marsh peat core was extracted using a gouge auger, and chronologically constrained using five radiocarbon age determinations by accelerator mass spectrometry, which places the record within the late Holocene period. Fossil foraminifera were analysed at a high downcore resolution, and a transfer function was applied to produce a relative sealevel reconstruction. The reconstructed sea-level curve depicts a transgression prior to 1100 cal years BP which correlates with existing palaeoenvironmental literature from southern Africa. From ~1100 to ~300 cal years BP, sea levels oscillated (~0.5-m amplitudes) but remained consistently lower than present-day mean sea level. The lowest recorded sea level of −1±0.2 m was reached between 800 and 600 cal years BP. After 300 cal years BP, relative sea level has remained relatively stable. Based on the outcomes of this research, we suggest that intertidal salt-marsh foraminifera demonstrate potential for the high-resolution reconstruction of relative sea-level change along the southern African coastline.In the southern African context, the application of foraminifera as biological indicators has been restricted to studies of stratigraphy 26 , temperature change 27 , sedimentology [28][29][30][31] and marine records 32 . The use of salt-marsh foraminifera to reconstruct relative sea-level change has been limited to a single published study at Langebaan. 33 Here we introduce an established sea-level proxy to determine proof of concept for South African sea-level research. This technique has the potential to contribute to our incomplete understanding of past sea-level change along the southern African coastline. HOW TO CITE:Strachan KL, Finch JM, Hill T, Barnett RL. A late Holocene sea-level curve for the east coast of South Africa. S Afr J Sci. 2014;110(1/2), Art. #2013-0198, 9 pages. http://dx.

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Salt-marsh foraminifera are used as precise sea-level change indicators as surface assemblages vary in relation to their position in the tidal frame. Surface-sediment samples were collected across an elevation gradient at Galpins salt marsh, South Africa, to study the vertical distribution of foraminifera and their potential use for sea-level studies. The marsh is divided into three vertical zones (high marsh, middle marsh, and mud flats) represented by three assemblage groups, with agglutinated species restricted to the upper reaches of the marsh and calcareous species more dominant towards the intertidal channel. The high marsh area is dominated by Jadammina macrescens with a presence of Trochammina inflata. The middle marsh is characterised by both T. inflata and Miliammina fusca. Calcareous species found in the mud flats consist of Haynesina germanica, Ammonia batava, and Quinqueloculina sp. This paper describes how marsh foraminifera can be used to define small-scale vertical zones along modern marsh surfaces and how these zones correspond to floral zones. We demonstrate that marsh foraminifera have potential to be used as precise indicators for sea-level reconstructions in South Africa.

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Name of collaboration Purpose of collaboration Urban resilience pilot projectCollaborative effort between different ministries for mapping and identifying climate risk areas in Blantyre, especially those prone to flooding disasters, such as landslides. Pilot project, with Blantyre as a pilot city, to be implemented across all city councils if seen to be effective in terms of building resilience in urban areas.8. Co-management of the environment between Blantyre City Council and city residentsTo engage the civic, educate residents and citizens on the importance of managing the urban tree system and forests, to avoid deforestation for charcoal, wood fuel or brick burning, as well as to manage human settlement encroachment on reserve areas (related to subsistence farming). 9. Multi-sectoral coordinating committees Multi-sectoral coordinating committees (working groups) that include stakeholders in the health, sanitation and environment sector, who come together to understand what scenarios would develop under different climate conditions, for example flooding or drought, and how this might affect residents and city service delivery mandates. 10. Environmental Affairs Department focal point deployment to town planning committee Through deployment collaboration, the Environmental Affairs Department (at national level) acts as a member of the Blantyre Town Planning committee in order to ensure that the issues of environment and climate change related issues are integrated in the planning at the city level. The role is to advise the planners with regards to these issues.