Mangrove Extents - GIS Layer


File ID: D33B0FED-6888-40EC-A56D-DA6C31E383DA
Hierarchy Level: dataset
Abstract: Spatial datasets showing the historic and current distribution for mangroves in the Waikato Region.
Statement: The mangrove extent and indicator harbour datasets are based delineating the mangrove extent on interpretation of aerial photographs taken in 2002, 2012 and 2017 from Waikato Regional Aerial Photographs (WRAPS), and historic imagery. The MANGROVE_EXTENT layer was created in December 2011 by BECA and Natural Solutions, and is currently (26th May 2021) being updated by Hannah Jones, WRC Coastal Scientist with more completed historic aerial imagery. Contact Hannah for data supply of this dataset. Field surveys of estuarine vegetation also assisted, and oblique aerial imagery have helped in the interpretation of the aerial photographs.
Keywords: Biodiversity,Coastal,Ecosystems,Harbour,Mangroves,Species,Trees,vegetation
Topic Category: environment:environmental resources, protection and conservation
oceans:features and characteristics of salt water bodies (excluding inland waters)
Resource Reference Date: 23/10/2012
Metadata URL: https://data.waikatoregion.govt.nz:8443/ords/f?p=140:12:0::NO::P12_METADATA_ID:1036

Responsible Parties

Role: owner
Position:
Organisation: Waikato Regional Council
Delivery Point: 160 Ward Street
City: Hamilton Central
Postal Code: 3204
Country: New Zealand
Phone:
Fax:
Email:
Role:
Position:
Organisation: Natural Solutions – Marine & Terrestrial Ecologists Ltd
Delivery Point: 8b Margaret Rd, Bellevue
City: Tauranga
Postal Code: 3110
Country: New Zealand
Phone: 07 576 0770
Fax:
Email: hamish@ecologist.co.nz
Role:
Position:
Organisation: BECA Ltd
Delivery Point: 32 Harington Street
City: Tauranga
Postal Code: 3110
Country: New Zealand
Phone: 07 578 0896
Fax:
Email:

Metadata

Language: English
Character Set: utf8
Standard: ANZLIC
Standard Version: 1.1

Metadata Constraints

Access Constraints: copyright
Use Constraints: copyright

Download Links

URLFormatNotes
 mangroves.htm HTML Mangrove options report webpage

Supporting Information Links

URLFormatNotes

General Notes: Users of this dataset should be aware of the difficulty with estimating the historical extent of mangroves from poor quality aerial photography and the inherent inaccuracies that will be in the polygons representing mangrove distribution. Mangrove Growth - Revised (EWDOCS # 1208680) Assessment of Different Mangrove Removal Options – Letter from Beca (EWDOCS # 1226565) Mangroves Option Report (EWDOCS #1196590). Mapping of historical extent of mangroves in Tairua Harbour – (EWDOCS # 2105871)

SCIENCE.sdeadmin.MANGROVE_EXTENT

 
File Identifier: C71C19B1-1D74-491E-A269-9F266AF019AA Parent Identifier: B8277C22-4116-4E95-958E-5AEFF1407F7C
Hierarchy Level: feature Hierarchy Level Name:feature of Mangrove Extents - GIS Layer
Abstract: Mangrove extent for 8 different years from 1944 – 2002. This work was carried out by BECA and Natural Solutions in December 2011. The dataset MANGROVE_EXTENT_INDICATOR_ESTUARIES now replaces this data layer as of October 2021.
Statement: Mangrove extent for 8 different years from 1944 – 2002.
Other Information: Geographic Extent: Mangrove2002, Mangrove1993, Mangrove1978, Mangrove1965, Mangrove1963, 1973, 1978, Mangrove 1944 - Whangamata Harbour from its northern-most reaches to just upstream of the Port Road Wharf and the Moanaanuanu Estuary upstream to the SH25 Bridge. Mangrove1973 - Moanaanuanu Estuary Tairau Harbour New Zealand Transverse Mercator. Northern Extent: 5902009, Southern Extent: 5896956 Eastern Extent: 1854226, Western Extent: 1851843 NZ Map Grid Co-ordinates: Whangamata: Centred on NZMS260 T12:645-425 Positional Accuracy: Whangamata Data is indicative only and has been captured from registered imagery. Tairua Harbour: The aerial photograph tiles that make up each year do not accurately overlap, with up to a ~40m offset between them. The aerial tile with the clearest picture was used for determining mangroves, and this tile name is recorded in a column in the attribute table for each mangrove polygon. Period and Frequency of Record: Whangamata: Relied on the availability of Aerial Photography. 1944, 1963, 1966, 1973, 1978, 1993 aerials available but only 1993 and 1978 were complete for the whole Harbour. 1944 ,1965 and 2002 data was sourced from Cawthron Institute Data. Tairua Harbour: This is a one-off assessment, although it could be updated with improved geo-rectification. Data Acquisition Method(s): Whangamata Data was sourced from Beca and Cawthron Institute. Methodology involved: 1. Hard copy aerial photography supplied by Waikato Regional Council to Beca. 2. Aerials scanned at 200 DPI and registered against cadastral data (SKM 01/02/07) 3. Extent of mangroves manually digitised off aerials. Where image coverage was unavailable the extents were inferred from an available data set closest in time to that particular date (See below). 4. Data and registered imagery supplied to Waikato Regional Council. 1944, 1965 and 2002 data sourced from earlier Cawthron Institute project. Methodology unknown. Mangrove Data Capture Summary from Beca: The data capture for the mangroves was based around data supplied from Paul Barter Marine Scientist - Coastal & Freshwater Group ,Cawthron Institute (original AVRE Data supplied on Beca CD), and Aerial photography that has been registered against cadastral boundaries. The differing coverage’s of the photography has resulted in the following procedures being used for the production of the following mangrove layers. Mangrove 1944 Very poor photograph coverage for this year. Used the AVRE 1944 data and removed small polygons (<100m2, too small for this investigation) Mangrove 1963 Very poor photograph coverage. Used the 1965 data and added one polygon to the south that could be seen on the little imagery that there was. This layer was not used for the investigation as data too unreliable. Mangrove 1965 No 1965 photography available so used the AVRE 1965 data and again removed small polygons (<100m2, too small for this investigation) Mangrove 1973 Very poor photograph coverage. Captured polygons where photography allowed. Did not use this data set in the investigation as the coverage was too small and only southern part of the harbour was covered. Mangrove 1978 Good photograph coverage, only the very Southern and Northern extents of the harbour missing. Used the 1973 captured data for the Southern tip and 1965 data for the Northern tip of the harbour. Apart from this data capture was from the registered photography. Mangrove 1993 Complete photograph coverage. Used current (2002) AVRE data as base and clipped this back to follow registered 1993 imagery. Mangrove 2002 No photograph coverage at all, used the current (2002) AVRE data. Tairua Harbour: The probable occurrence of mangroves in Tairua Harbour from the 1944 and 1971 aerial photographs is estimated. These estimates are based on the visibility of mangroves in the aerial photographs and field experience mapping estuarine vegetation from aerial photographs. The following are the type of errors that will be present in the mangrove area data mapped: It is likely that small mangroves or isolated plants that are not obvious on the aerial have been missed. A precautionary approach has been taken and where it is uncertain whether or not a shape is mangrove it has not been mapped as mangrove. Some areas that look like mangrove, and have been mapped as such, may in fact not be. Data Quality: Whangamata: There is confidence in the trends depicted and scale of mangrove change with time. However, the use of inference to map mangrove extents when aerial imagery is unavailable means that there is considerable uncertainty as to the actual extents at that time. Data was captured from registered imagery which was not orthorectified and is approximate only. Tairua Harbour: Where possible, the source data utilised to create this dataset comprises the most current available information and is derived from quality assured regional council or nationally recognised datasets and expert knowledge. Due to variance in georectifying of the different year aerial photographs the mangrove areas mapped cannot be overlayed to show a time sequence of change. A layered time sequence of mangrove areas could be attempted, but this would require improved geo-rectifying of the different aerial photographs between years and between the aerial tiles that make up each year. Attribute Accuracy: There are very few attributes supplied by BECA or Natural Solutons. Only some area attributes are populated and these appear to be done using true spheroidal measurement interpretation. All area calculations checked were accurate to within 0.003 of a hectare. The update in October 2012 to include Tairua Harbour data included area and perimeter calculations on the polygons supplied by Natural Solutions to populate the attributes. No changes were made to the Whangamata data at this point other than to rename attributes fields to make them more generic for future proofing. Completeness: - Mangrove1973 only covers Moanaanuanu Estuary. - Mangrove1993, Mangrove1978, Mangrove1973, Mangrove1963 and Mangrove1944 have no perimeter attributes. - Mangrove1978 and Mangrove1973 have no area attributes. The use of inference to map mangrove extents when aerial imagery is unavailable must mean there is considerable uncertainty as to the actual extents at that time. This would be considered a generalisation that is applied to the data. The limitations of the data sets increase depending on how much of the data was digitised off registered imagery or inferred from other data sets. It appears the 2002 layer would have few limitations as it may have been digitised directly off a complete coverage of accurate orthorectified imagery. The data is indicative only, and should be considered more an estimate of mangrove extent, especially where inference has been used. The data should not be used for purposes other than where indicative data is appropriate. The dataset is complete for the Tairua Harbour. Logical Consistency: Data from the Cawthron Institute (1944, 1965, 2002) was used to verify other data that was digitised but the accuracy and methodology behind the Cawthron data is unknown. It is unknown of any other QA carried out on the data sets. Area attributes were randomly checked in GeoMedia using Analyze Geometry. Due to the use of inference some data sets have the same boundaries in places (1963/1965, 1973/1978, 1993/2002). Data Form: Digital spatial data / images. Whangamata data was provided on a CD by Beca. The CD contained GIS files (Mapinfo and ESRI) of Mangrove extents, Original Historic images that ere used to capture data, various spreadsheets with attributes and calculations and a Powerpoint displaying some of the images and GIS data. Tairua Harbour data was supplied as ESRI shape files. Applications: The data sets are designed to provide an overview of ‘historic baselines’ for mangrove extents Reports that use the data include: Mangroves Option Report (EW Docs #1196590). Mapping of historical extent of mangroves in Tairua Harbour – (EWDOCS # 2105871) Websites that use that data include: Mangrove options report webpage (http://www.waikatoregion.govt.nz/projects/whangamata/mangroves.htm). The data is shown as maps in the Mangrove Options Report (EW Docs # 1196590) and as thumbnails and full size popups on the mangrove options report webpage (http://webdevel/projects/whangamata/mangroves.htm).
Keywords: Biodiversity,Ecosystems,Harbour,Mangroves,Ocean,Species,Trees,vegetation
Topic Category: environment:environmental resources, protection and conservation
oceans:features and characteristics of salt water bodies (excluding inland waters)
Resource Reference Date: 23/10/2012

Metadata Constraints

Access Constraints: copyright
Use Constraints: copyright

Maintenance Information

Maintenance frequency: asNeeded
Last Load Date: 23/10/2012

Spatial Representation Information

Recommended Scale:
Reference System: EPSG2193
Spatial Representation Type: vector

VectorGridGeographic Bounding Box
GeometricObjectType : surface
geometricObjectCount : 267
topologyLevel : geometryOnly
Number of Dimensions :
Cell Geometry :
Transformation Param Available : N
westBoundLongitude : 1854869.6139
eastBoundLongitude : 1851843.3703
southBoundLatitude : 5877785.6748
northBoundLatitude : 5902008.6244

Responsible Parties

Role:
Position:
Organisation: Waikato Regional Council
Delivery Point: 160 Ward Street
City: Hamilton Central
Postal Code: 3204
Country: New Zealand
Phone:
Fax:
Email:

Data Constraints

Data Access Constraints : copyright
Data Use Constraints: copyright
Data Distribution: Third party, internal permission
Licence Type : To be determined
Licence:
Licence Expiry:
Licence Conditions: Contact Hannah Jones for data supply as at 26th May 2021 as this layer may be improved with other data layers as they become available.
Copyright : All outputs showing the data should include the following acknowledgement: ‘Whangamata Mangrove Extent sourced from Waikato Regional Council and is indicative only. COPYRIGHT RESERVED.’
Data Disclaimers : ‘DISCLAIMER : While Waikato Regional Council has exercised all reasonable skill and care in controlling the contents of this information, Waikato Regional Council accepts no liability in contract, tort or otherwise howsoever, for any loss, damage, injury or expense (whether direct, indirect or consequential) arising out of the provision of this information or its use by you.’ The following disclaimer from Beca must also be included where applicable: ‘This map contains data derived in part or wholly from sources other than Beca, and therefore, no representations or warranties are made by Beca as to the accuracy or completeness of this information.’ Tairua Harbour - There must be acknowledgement of Natural Solutions – Marine & Terrestrial Ecologists Ltd as the creators of the dataset.
Data Use Limits : This work was carried out by BECA and Natural Solutions in December 2011, and is currently being updated by WRC (26 May 2021)using more complete historic aerial imagery by Hannah Jones, WRC coastal scientist.

Download Links

URLFormatNotes

Supporting Information Links

URLFormatNotes

General Notes: phone: (06) 869 0474

Attribute Information

NameDescriptionNotesRestrictedPrimary Key
YEAR Year Extent Represents N N
AREA See individual year information* historically been supplied as a mixture of square metres or hectares. Details are as follows: Years 1993, 1978, 1963, 1944 (Whangamata) – Area is shown in hectares. All other years and 1944 (Tairua) the Area attribute is in square meters or not populated N N
HECTARES Area of polygon in hectares N N
PERIMETER Perimeter of polygons in metres N N
GEOMETRY N N
SUPPLIER_LAYER The name of the layer originally supplied N N
AERIAL_TILE The aerial photograph tile within which the polygon sits N N
ID1 The unique identifier for the Beca supplied polygons only N N
ID WRC primary key and unique identifier N Y

SCIENCE.sdeadmin.MANGROVE_EXTENT_2012

 
File Identifier: 6F0C1A6A-4015-1668-E055-000000000001 Parent Identifier: D33B0FED-6888-40EC-A56D-DA6C31E383DA
Hierarchy Level: feature Hierarchy Level Name:Feature of Mangrove Extents - GIS Layer
Abstract: Mangrove Extent using WRAPS 2012 as a basis to delineate mangroves in the Waikato Region.
Statement: This dataset used WRAPS 2012 as a basis to delineate mangrove extent in the Waikato Region. However this dataset is by no means a comprehensive improvement as there are still notably Waikawau Bay and Raglan Harbour that needs further work. These areas will be updated as needed. The mangrove extent used ESUTARINE VEG 2007 data layer as a basis and included more later mangrove improvements using the latest version of BIOVEG 2012 (v.4) and manual digitizing to delineate boundaries more accurately. Google street view was also used to check mangrove vegetation growth. TCDC Urban imagery 2015 was used for mapping mangrove removal from 2012-2015 for Whangamata Harbour.
Other Information: Other datasets used were ESTUARINE VEG 2007, and specifically querying out mangroves, BIOVEG 2012 (v.4 2018 update), HGMSP ESTUARINE VEGETATION, and Google Street View was used where roads were close to mangrove areas and validate mangrove growth and extent. TCDC Urban imagery 2015 was used for mapping mangrove removal from 2012-2015 for Whangamata Harbour. THese areas are identified in the DATA_SOURCE field, and show areas of mangrove removed in the 2015 imagery. If you want to remove these mangroves from the data to show mangroves in Whangamata Harbour as at 2015. In ArcGIS Data layer > Properties> Definition query tab > copy in - DATA_SOURCE NOT IN ('Mangroves removed in 2015 TCDC urban imagery') This function will remove mangroves to match imagery at 2015 (2015 TCDC Urban Imagery). Data layer descriptions refer to https://discover.wairc.govt.nz/otcs/llisapi.dll/link/12664616
Keywords: Aerial photography,Harbour,Mangroves,Ocean,vegetation
Topic Category: biota:flora and/or fauna in natural environment
environment:environmental resources, protection and conservation
geoscientificlnformation:information pertaining to earth sciences
oceans:features and characteristics of salt water bodies (excluding inland waters)
Resource Reference Date: 20/06/2018

Metadata Constraints

Access Constraints: copyright
Use Constraints: copyright

Maintenance Information

Maintenance frequency: asNeeded
Last Load Date: 11/01/2019

Spatial Representation Information

Recommended Scale: 1:2,000
Reference System: EPSG2193
Spatial Representation Type: vector

VectorGridGeographic Bounding Box
GeometricObjectType : surface
geometricObjectCount : 3339
topologyLevel : geometryOnly
Number of Dimensions : 2
Cell Geometry :
Transformation Param Available : N
westBoundLongitude : 1856074.8753
eastBoundLongitude : 1762719.0958
southBoundLatitude : 5811335.6045
northBoundLatitude : 5955132.4881

Responsible Parties

Role: pointOfContact
Position: Coastal Scientist
Organisation: Waikato Regional Council
Delivery Point: 160 Ward Street
City: Hamilton Central
Postal Code: 3204
Country: New Zealand
Phone:
Fax:
Email:

Data Constraints

Data Access Constraints : license
Data Use Constraints: license
Data Distribution: Unrestricted
Licence Type : Creative Commons - CC BY 4.0
Licence: https://creativecommons.org/licenses/by/4.0
Licence Expiry:
Licence Conditions: Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Copyright : Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
© Waikato Regional Council 2012 Mangrove Extent. Licensed under CC BY 4.0.
Data Disclaimers : While Waikato Regional Council has exercised all reasonable skill and care in controlling the contents of this information, Waikato Regional Council accepts no liability in contract, tort or otherwise howsoever, for any loss, damage, injury or expense (whether direct, indirect or consequential) arising out of the provision of this information or its use by you.
Data Use Limits : Limitations on scale used 1:2,000. Data used WRAPS 2012 so what is shown is only indicative of current extent. WRAPS 2017 was not available for this work.

Download Links

URLFormatNotes

Supporting Information Links

URLFormatNotes

General Notes: Data input descriptions https://discover.wairc.govt.nz/otcs/llisapi.dll/link/12664616

Attribute Information

NameDescriptionNotesRestrictedPrimary Key
OBJECTID_1 N N
AREA_HA Area in hectares Area in hectares N N
LOCATION Location of mangrove extent Location of mangrove extent N N
ESTUARINE_VEG_TYPE Estuarine vegetation type Estuarine vegetation type N N
AERIAL_IMAGERY Aerial imagery Aerial imagery year used to delineate mangrove extent N N
DATA_SOURCE Data source Name of data source used, or multiple types of data sources used. N N
ID N N
GEOMETRY N N

SCIENCE.sdeadmin.MANGROVE_EXTENT_INDICATOR

 
File Identifier: CF5F21B4-8601-504E-E055-000000000001 Parent Identifier: D33B0FED-6888-40EC-A56D-DA6C31E383DA
Hierarchy Level: feature Hierarchy Level Name:feature of Mangrove Extents - GIS Layer
Abstract: Spatial dataset showing the historic and current distribution for mangroves in four estuaries in the Waikato Region. This layer replaces the MANGROVE_2002_INDICATOR_HARBOURS, MANGROVE_2012_INDICATOR_HARBOURS, and MANGROVE_2017_INDICATOR_HARBOURS which will be made obsolete.
Statement: This layer was created in 2021. Mangrove extent in the Firth of Thames, Coromandel Harbour, Tairua Harbour, and Whāingaroa (Raglan) Harbour, was digitised from available historical, orthorectified aerial photographs taken between 1944 and 1997, and WRAPS images taken in 2002, 2006, 2012 and 2017. These were digitised in ArcGIS Pro at between 1:1,000 and 1:3,000 scale. Field surveys of estuarine vegetation undertaken between c. 2000 and 2012, and oblique aerial imagery captured in 2016, helped in the interpretation of recent aerial imagery. For the purposes of the digitisation, the boundary of mangrove extent was defined as where mangrove exceeded c. 50 % cover. Mangrove coverage is often patchy, and the boundaries of mangrove stands are sometimes not well defined, especially where there are smaller trees and seedlings on the seaward mangrove fringe. Mangrove trees can also be mixed with other types of vegetation, such as saltmarsh, especially on the landward fringe. These factors can make it difficult to determine and digitise the exact location of the boundary between mangrove and other habitat. Mangrove extents should therefore be considered approximate
Other Information: This datasets is used in the production of the “Extent of Coastal Habitats” environmental indicator on the WRC website.
Keywords: Biodiversity,Coastal,Ecosystems,Harbour,Mangroves,Species,Trees,vegetation
Topic Category: environment:environmental resources, protection and conservation
oceans:features and characteristics of salt water bodies (excluding inland waters)
Resource Reference Date: 28/10/2021

Metadata Constraints

Access Constraints: copyright
Use Constraints: copyright

Maintenance Information

Maintenance frequency: notPlanned
Last Load Date: 10/11/2021

Spatial Representation Information

Recommended Scale: 1:5,000
Reference System: EPSG2193
Spatial Representation Type: vector

VectorGridGeographic Bounding Box
GeometricObjectType : surface
geometricObjectCount : 12649
topologyLevel : geometryOnly
Number of Dimensions : 2
Cell Geometry :
Transformation Param Available : N
westBoundLongitude : 1854333.7443
eastBoundLongitude : 1762693.5421
southBoundLatitude : 5811333.1494
northBoundLatitude : 5929879.9976

Responsible Parties

Role:
Position:
Organisation: Waikato Regional Council
Delivery Point: 160 Ward Street
City: Hamilton Central
Postal Code: 3204
Country: New Zealand
Phone:
Fax:
Email:

Data Constraints

Data Access Constraints : license
Data Use Constraints: license
Data Distribution: Unrestricted
Licence Type : Creative Commons Attribution 4.0 International (CC BY 4.0)
Licence: https://creativecommons.org/licenses/by/4.0/
Licence Expiry:
Licence Conditions:
Copyright : Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
© Waikato Regional Council 2021. Mangrove Extent Indicator Estuaries
Data Disclaimers : ‘DISCLAIMER : While Waikato Regional Council has exercised all reasonable skill and care in controlling the contents of this information, Waikato Regional Council accepts no liability in contract, tort or otherwise howsoever, for any loss, damage, injury or expense (whether direct, indirect or consequential) arising out of the provision of this information or its use by you.’
Data Use Limits : Unrestricted data use, contact Hannah Jones, Coastal and marine group WRC for queries relating to this dataset.

Download Links

URLFormatNotes

Supporting Information Links

URLFormatNotes

General Notes:

Attribute Information

NameDescriptionNotesRestrictedPrimary Key
OBJECT_ID Object ID field generated by ArcGIS Object ID field generated by ArcGIS N Y
LOCATION Geographic location of mangroves Geographic location of mangroves N N
ESTUARINE_VEG Description of estuarine vegetation type Description of estuarine vegetation type N N
AERIAL_IMAGERY Aerial imagery used to delineate mangrove extent Aerial imagery used to delineate mangrove extent N N
DATA_SOURCE Data source used to delineate mangrove extent Data source used to delineate mangrove extent N N
YEAR Year of aerial survey used to delineate mangrove extent Year of aerial survey used to delineate mangrove extent N N
AREA_HA Area of mangrove extent measured in hectares Area of mangrove extent measured in hectares N N
GEOMETRY N N