Layer Groups Click on one of the links below to jump to that group of layers.
GIS Layers Click on the name hyperlink of a layer to jump to the detailed description information for that layer.
| Birds |
|
Data on 16 different birds and their habitats for 1991 and for 2007. All bird maps for 1991 have been digitised from the book: The Estuary Where Our Rivers Meet The Sea (1992), edited by S.J Owen. The source of information is Andrew Crossland, Park Ranger, Christchurch City Council. While a single original map included different species with their spatial and temporal distributions, the digitised ones have been created on a per bird basis. Each layer is named after the bird suffixed by source year. Data generally covers species type, roosting and nesting sites, seasonal, tidal and maximum distributions, and main and secondary feeding areas. Data attributes are the same in all layers, with a species code and year (plus the oid) making a record unique. The attributes include common bird name, bird code, maori name, scientific name, area/habitat type, area type/habitat code, period of data, a sort year, source details, and publication time. Using the 1991 GIS maps as a base, Andrew Crossland manually updated the birds data for 2007, and these were then screen-digitised. Due to time constraints, only the following birds were selected by Andrew for processing from a wider variety of the estuary birds: White-faced Heron, NZ Shoveler, Black Swan, Canada Goose, South Island Pied Oystercatcher, Eastern Bar-tailed Godwit, Pied Stilt, Pukeko, Royal Spoonbill, Little Cormorant, Black Cormorant, Little Black Cormorant, Pied Cormorant, Spotted Shag, Variable Oystercatcher, Black-billed Gull and Southern Black-backed Gull. |
| Shags and Cormorants |
| Pied Stilts |
| Gulls |
| Pied Oystercatcher |
| Variable Oystercatcher |
| Godwits |
| Royal Spoonbill |
| Pukeko |
| Black Swan |
| Canadian Geese |
| White-faced Heron |
| NZ Shoveler |
| Birds Habitats |
| Benthic fauna |
|
Benthic fauna are organisms attached to or resting on the bottom or living in the bottom sediments of a water body. The layer within this group shows five sampling sites, where the type of benthic fauna was identified and numbers counted (per 0.25m2 and per 0.0133m2) at each site. The five different sites each measure 60mx40m in area. 15 different samples taken at each site. Atributes within each layer provides link where users can download the results data. |
| Sampling Quadrants |
| Fish |
|
Fish data on species variety, size in length, counts and density (per 1000m2) is being gathered by NIWA on an on-going study commissioned by the Christchurch City Council since 2005. The data available now is for 2005 and 2006, with 2007 being processed by NIWA now. Data was gathered through two main methods: Seine (beach sites) and Trawl (through the main channels). Seine sites were provided in a geographic point shapefile and trawl lines in a polygon shapefile, and the actual fish data in tables. The geographical sites were then mapped to their tabular data based on the site id and four data layers created. Each layer represents a method for each year. Layers are named to reflect this breakdown: Fish2005seine.shp, Fish2005Trawl.shp, Fish2006Seine.shp, Fish2006Trawl.shp. A record is unique in each layer through the combination of fish species and site identifier. |
| NIWA Study |
| Seagrass |
|
Seagrasses (e.g. Zostera, Posidonia ) are rhizome angiosperm grasses adapted to live underwater in shallow estuaries and sheltered lagoons. Conservation of seagrass beds is important for nutrient productivity and to provide habitat for juvenile fish. Point locations of main clusters of seagrass were recorded with a Garmin GPS unit in 2004 for Associate Professor Islay Marsden in the Biological Sciences Department at the University of Canterbury. The recordings were repeated again in February 2007 by the same person. Along with the seagrass locations, markers on the eastern and western sides of the estuary on the same (or close) latitude were taken. All data were transferred out of the Garmin machine in a software called Mapsource, and the coordinates reprojected in ArcMap to come up with the shapefiles. Each years data was extracted into its own file, and the survey markers also extracted into a markers file. Currently only 2004 data is displayed on the portal. 2007 data will be cleared by Islay Marsden later for use on the portal. No useful attribute data is in these files, except for the coordinates. The last seagrass layer is from the Cawthron Institute, a part of a larger dataset on the broadscale habitat mapping of the estuary Cawthron did from aerial photos flown in January 2000. |
| University of Canterbury Study |
| Cawthron Institute Study 2002 |
| Salt marsh |
|
Saltmarsh data is from two different sources on the areal locations of salt marshes within the Avon-Heathcote Estuary. Kimberly Jupp, a student in Geography from the university of Canterbury undertaking a summer project in 2006/2007 recorded using a GPS unit the locations of saltmarshes around the estuary, and identified the dominant species in specific saltmarshes. This was done to repeat a previous study and to compare results against, therefore not all salt marshes were captured. Other data on salt marshes are provided by the Cawthron Institute who undertook a study from 2000/2002 which mapped estuarine substrates and habitats on a broadscale of 9 estuaries around the country, including the Avon-Heathcote Estuary. This was done through image analysis of a January 2000 Aerial photograph of the Avon-Heathcote estuary, and its habitats classified and broadly mapped through this technique. |
| University of Canterbury Study |
| Saltmarsh - Cawthron Institute Study 2002 |
| Water Quality |
|
These layers include those assocaited with water quality, in particular contaminant sampling. The water quality contaminants layer shows sampling sites in the estuary currently used by Environment Canterbury. Classification of water quality for contact recreation is given for various sites. The suitability for recreation grades indicate which sites would be suitable for recreation/swimming. |
| Environment Canterbury Layers |
| Estuary structures and edges |
|
This group of layers consist of data collected mainly through the use of GPS units. Most are from the University of Canterbury courtesy of student Kimberly Jupp from the department of Geography. Kimberley recorded the margins of the estuary in January and February 2007, and classified into different layers what material the edges were made of. This included soft and hard edges. Positons of built structures like bridges, ramps, jetties and metal tracks, and natural things like freshwater inlets were all captured. Other structures data come from Environment Canterbury such as reclamations and stormwater culverts. From the individual edges data, two estuary margins layers have been created in line and polygon formats. Where there have been gaps, screen digitising have filled them in to complete the outlines. |
| Margin outlines |
| Structures |
| Modified boundaries |
| Tracks |
| Channels |
| Macroalgae |
|
Data on macroalgae come from two different sources. Macroalgae distribution maps from studies conducted over time were referenced and recompiled in a 2003 masters thesis by Melanie Bressington, University of Canterbury. The studies ranged from 1950/51 to Melanie's own study data of 2003. The replicated maps and her own original maps from the thesis were georeferenced to the estuary areal map, and digitised. A common database was used for all layers with the attributes capturing period of survey, what percentage cover the algae took up, the name of researcher and time study got published. Other data on macroalgae comes from the Cawthron Institute as part of a larger dataset from their study: Estuarine Environmental Monitoring and Assessment: A National Protocol (2002). Macroalgae areas within the Avon-Heathcote estuary were classified as such from analysis of an aerial photograph flown for Environment Canterbury in January 2000. |
| Percentage Cover 1950-2003 - Bressington 2003 |
| Broadscale Mapping - Cawthron Institute 2002 |
| Sediment |
|
One lot of sediment data is from the two councils. From five sampling sites, sediment grain sizes are measured to identify type, and the concentrations of the metals cadmium, chromium, copper, lead, nickel and zinc in the sediment are measured. Samples taken 2005 and 2007, at five different sites each measuring 60mx40m in area. At each site, 10 different samples taken for all sediment measures. Data on sediment from the Cawthron Institute were sourced from their 2000/2002 study which mapped estuarine substrates and habitats of 9 estuaries on a broadscale using image analysis. The Avon-Heathcote estuary's substrates were mapped from a January 2000 Aerial photograph. |
| Sampling Sites |
| Mud/Sand Flats |
| Navigational ByLaws |
|
Layers relating to navigation safety issues including separating areas for particular purposes such as water skiing, swimming and sailing; and the wearing of lifejackets by children in small craft. navigational hazards like sand banks; restricted areas and craft allowed/not allowed areas; facilities and speed limits. |
| Regional Coastal Environment Plan Areas (Environment Canterbury) |
| Bylaws |
| Soils and Geological |
|
Soiling characteristic mapping for the areas surrounding the estuary, clipped from a larger Christchurch City Soil Map courtesy of Landcare Research. The data includes attributes on soil type, land use capability and urban use classification. |
| Soils Types |
| Heritage, Special Character |
|
Layers related to locations and buildings that have been identified as being of cultural, heritage, historical, & ecological value to the community, or have special character. These layers were sourced from the Christchurch Ciy Council. |
| Heritage settings and areas |
| Ecological and natural areas |
| Archeological sites |
| Amenity areas |
| Erosion |
|
Layers related to erosion including areas of risk, recorded instances of, areas of remediation and management. These layers were sourced from Christchurch City Council and the University of Canterbury. |
| Management and remediation |
| Erosion risk and historical observations |
| Regional and administrative areas |
|
Layers depicting admisinstrative boundaries, surface water catchments, areas of Crown land, and land use activity designated within the city plan |
| Waterfront |
|
Layers related to the waterfront area, including vegatative and geomorphic change on Brighton Spit, and regulatory areas such as the Coastal Marine Area landward boundary, the Coastal Hazard Zone boundary, and the Coastal Setback boundary |
| Historical observations of Brighton Spit |
| Regulatory Areas |
| Esplanades and reserves |
| Water network structures |
|
Layers related to the Christchurch's water courses and water utility network (water supply, stormwater, and wastewater), particularly in the vicinity of the Avon-Heathcote Estuary Ihutai. |
| Rivers, streams and drains |
| Stormwater |
| Watersupply |
| Wastewater |
| Facilities and recreation |
|
Layers showing the location of recreation and community facilities near the Avon-Heathcote Estuary Ihutai, including walking tracks, and sports grounds. |
| Tracks |
| Facilities |
| Background and base layers |
|
These layers show base information designed to help locate objects, including areas and lines of interest within the estuary and in the surrounding suburbs, and are currently used in the Bibliographic Tool on the Avon-Heathcote Estuary Ihutai Trust website. These areas of interest are created as polygons, and annotated labels used to identify them. For the purposes of this where such areas are used as identifiers of landmarks, the polygons display transparently to avoid clutter and the labels identify the general vicinity of these areas. |
| Cadastral and road layers |
| Landmarks |
| Other layers |