Parent Layer:
Aquatic Biodiversity Theme
Name: Estuarine Functional Zone
Display Field: Estuary_Name
Type: Feature Layer
Geometry Type: esriGeometryPolygon
Description: 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.
Service Item Id: d127b5639ad04693b5a403f6d7eb383f
Copyright Text:
Default Visibility: false
MaxRecordCount: 2000
Supported Query Formats: JSON, geoJSON, PBF
Min Scale: 500000
Max Scale: 0
Supports Advanced Queries: true
Supports Statistics: true
Has Labels: false
Can Modify Layer: true
Can Scale Symbols: false
Use Standardized Queries: true
Supports Datum Transformation: true
Extent:
XMin: 1773386.0013059054
YMin: -4146138.932439881
XMax: 3728713.897298745
YMax: -3100420.2851963164
Spatial Reference: 102100
(3857)
Drawing Info:
Renderer:
Simple Renderer:
Symbol: Style: esriSFSSolid
Color: [214, 133, 137, 255]
Outline:
Style: esriSLSSolid
Color: [0, 0, 0, 255]
Width: 0
Label: N/A
Description: N/A
Transparency: 0
Labeling Info:
Advanced Query Capabilities:
Supports Statistics: true
Supports OrderBy: true
Supports Distinct: true
Supports Pagination: true
Supports TrueCurve: true
Supports Returning Query Extent: true
Supports Query With Distance: true
Supports Sql Expression: true
Supports Query With ResultType: false
Supports Returning Geometry Centroid: false
Supports Binning LOD: false
Supports Query With LOD Spatial Reference: false
HasZ: false
HasM: false
Has Attachments: false
HTML Popup Type: esriServerHTMLPopupTypeAsHTMLText
Type ID Field: null
Fields:
-
OBJECTID
(
type: esriFieldTypeOID, alias: OBJECTID
)
-
Shape
(
type: esriFieldTypeGeometry, alias: Shape
)
-
EstuaryID
(
type: esriFieldTypeSmallInteger, alias: EstuaryID
)
-
Estuary_Name
(
type: esriFieldTypeString, alias: Estuary_Name, length: 70
)
-
SENSITIVIT
(
type: esriFieldTypeString, alias: Sensitivity category:, length: 15
)
-
THEME
(
type: esriFieldTypeString, alias: THEME, length: 40
)
-
SENSFEAT
(
type: esriFieldTypeString, alias: Sensitivity features:, length: 100
)
-
DEVELOP
(
type: esriFieldTypeString, alias: DEVELOP, length: 50
)
-
Shape_Length
(
type: esriFieldTypeDouble, alias: Shape_Length
)
-
Shape_Area
(
type: esriFieldTypeDouble, alias: Shape_Area
)
Supported Operations:
Query
Query Attachments
Query Analytic
Generate Renderer
Return Updates
Iteminfo
Thumbnail
Metadata