Marine Ecosystem Map

First version of an integrated coast map including coastal ecosystem types from the terrestrial, marine, and estuarine realms

This layer includes the threat status and protection level of the Marine Ecosystems 2018 assessed for the National Biodiversity Assessment 2018

Collation of available estuary submerged macrophyte distribution shapefiles. Presently 97 estuaries (listed in the appendix) are captured, and new maps will be added periodically as produced. The maps collated range in date from 2004-2018. Estuaries have been mapped as per the Estuary Health Index to determine Present Ecological Status. Some estuaries were mapped as Nelson Mandela University student theses. Shapefiles were also obtained from SANParks (Swartvlei and Wilderness estuaries). Currently nine data capturers were responsible for the development of GIS estuary maps. Macrophyte habitat descriptions may have been altered from the original published maps so as to standardize macrophyte habitat types. Distribution maps differ in extent, scale and accuracy as they were produced for differing outcomes. The shapefile is formatted in accordance with SANBI specifications. More recent maps produced are delineated according to the Estuarine Functional Zone (EFZ) which is considered the 5 m topographical contour (van Niekerk and Turpie 2012).

An extraction of the zone terrestrial land mass of South Africa until the ecologically determined dune base line from the first version of an integrated coast map including coastal ecosystem types from the terrestrial, marine, and estuarine realms

NBA2018_Terrestrial Ecosystem Threat Status and Protection level remaining extent layer is associated with the NBA2018_Terrestrial Ecosystem Threat Status and Protection level. While the a NBA2018_Terrestrial Ecosystem Threat Status and Protection level remaining extent provides the data for Protection level and threat status for the historical (pre 1750AD) extent of the terrestrial ecosystems, this layer shows the protection level and threat status of the current remaining extent of terrestrial ecosystems. More detail can be found in NBA 2018 Technical Report Volume 1: Terrestrial Realm, http://hdl.handle.net/20.500.12143/6370

An extraction of the zone from the dune base line to the edge of South Africa’s Exclusive Economic Zone (EEZ) from the first version of an integrated coast map including coastal ecosystem types from the terrestrial, marine, and estuarine realms

This is the most recent version of the Estuarine Functional Zone Map. The map was developed as a collaborative effort and delineates the Estuarine Functional Zone for South Africa (Van Niekerk et al. 2019). In South Africa, the EFZ is defined as the area that not only encapsulates the estuary waterbody, but also the supporting physical and biological processes necessary for estuarine function and health. It includes all dynamic areas influenced by long-term estuarine sedimentary processes, i.e. sediment stored or eroded during floods, changes in channel configuration, aeolian transport processes, and/or changes due to coastal storms. It also encompasses the multiple ecotones of floodplain and estuarine vegetation that contribute detritus (food source) to the estuary and/or provide refuge during high flow events. The EFZ captures the natural, historical estuarine extent and should not be confused with setback/management lines that often exclude developed areas. The EFZ purpose is to identify the ‘space’ in which estuarine physical and biological functions take place over long time scales (>decades). Development in the EFZ is captured as an aspect of habitat degradation or decline in overall estuary condition. The upstream boundary of the estuaries was determined as the limits of tidal variation or salinity penetration, whichever penetrates furthest. The estuary mouth was taken as the downstream boundary of an estuary. The highly dynamic nature of this area presents a significant challenge to accessing change in biodiversity and even managing estuaries. To account for this, and to allow for a seamless integration with the Marine and Coastal Realm, the concept of ‘Estuarine Shore’ was introduced to reflect the dynamic nature of the interface between estuaries and the coast. Estuarine Shores refers to sand berms or bars that form in front of estuaries. They vary substantially in size and shape over decadal scales and can be completely absent during a flood or a near permanent feature during periods of low flow. Estuarine Shore was defined as the area from the base of the foredune, or where this line would be if dunes were present, to the back of the surf zone. The full extent of the Estuarine Shore is encapsulated in the EFZs and not be considered separate from the functional unit. The surfzone was included to reflect a continuum in estuarine-marine connectivity through estuarine inputs to the surfzone, either as direct flow through an open mouth or in seepage through the berm in a closed system.

nba2025_terr _RLE_EPL_remnants layer forms part of the NBA2025 and is associated with the nba2025_terrl_RLE_EPL (large-scale industrial development) layer. The remnants layer shows the protection level and threat status of the current remaining extent of terrestrial ecosystems. It forms a key part of the National Biodiversity Assessment. For further details, see the relevant ecosystem threat status and protection level pages.

The nba2025_terr_rle_epl layer forms a key part of the National Biodiversity Assessment. The Red List of Ecosystems (commonly referred to as ecosystem threat status) and Ecosystem Protection Level are the two headline indicators used in South Africa to report on the state of its biodiversity. This dataset contains the historical / potential extent (circa 1750) of each of the 463 ecosystem types assessed. This means that patches of ecosystems lost to anthropogenic activities such as mining or croplands are part of the dataset. A separate dataset (nba2025_terr_rle_epl_remnants.shp) is also available and contains only the natural remaining remnants of each ecosystem type. This represents a revision of the “List of terrestrial ecosystems that threatened or in need of protection” published in the government gazette in December 2022. The revision is based on the best available data and uses the IUCN RLE risk assessment framework version 2.0 (IUCN,2024). Terrestrial ecosystems are categorised into one of four classes representing their risk of collapse; in descending order of risk: Critically Endangered, Endangered, Vulnerable, and Least Concern. The national vegetation map, 2024 version (Mucina and Rutherford 2006; Dayaram et al., 2025 in prep) provided the units of assessment for the RLE (Vegetation Unit / Type level) assessments. For further details, see the relevant ecosystem threat status and protection level pages.