Metadata : Northern Territory weeds dataset

Index:


Metadata Details:

Name:AS/NZS ISO 19115 Geographic Information - Metadata, ANZLIC Metadata Profile

Version:1.0

Date Metadata Extracted:2022-10-02

Date Metadata Last Updated:2018-09-17

Current URL (HTML format) : http://www.ntlis.nt.gov.au/metadata/export_data?type=html&metadata_id=CDC9FABDCF7A22CDE040CD9B21443996

Current URL (XML format) : http://www.ntlis.nt.gov.au/metadata/export_data?type=xml&metadata_id=CDC9FABDCF7A22CDE040CD9B21443996


Citation

ANZLIC Identifier:CDC9FABDCF7A22CDE040CD9B21443996

Title: Northern Territory weeds dataset

Citation Date:2003-06-01

Date Type:creation

Custodian:Department of Environment, Parks and Water Security


Description

Abstract:

The NT weeds dataset describes the 'presence' only point dataset compiled from various weeds surveys conducted in the Northern Territory. It also draws information from herbarium records, historical weeds records and other vegetation surveys.

The Northern Territory Weeds Dataset is largely a compilation of data derived from GPS locations attributed to describe weed species present and the size and density of those infestations. The datasets are used to assist the Weed Management Branch and the Northern Territory Government identify existing weed infestation locations and new weed incursions, to monitor control measures and report to various funding bodies.

The datasets are stored using geographics in Datum GDA94 in an ESRI file geodatabase format. All point data contains coordinate locations in decimal degrees. The data is managed by the Spatial Data Manager of the Weed Management Branch. The custodian is the Director of the Weed Management Branch.

It is important to note that weed infestations frequently change, reducing with successful control or increasing, expanding without management. Accordingly, recorded observations are valid only for the date of the record and expert opinion sought as to the likely current extent of weed infestation.

ANZLIC Search Words:

Spatial Domain:

Bounding Coordinates:


Dataset Status

Dataset ID:

Language:English

Character Set: Latin 1

Progress:onGoing

Maintenance and Update Frequency:continual

Data Currency Start Date:2003-06-01

Data Currency End Date:2017-12-31

Access Constraint:

Download the spatial data package (contains spatial data, maps and reports) via data.nt.gov.au/

You are licensed to use the DENR geospatial products on the terms and conditions set out in: Creative Commons Attribution 4.0 International Public License (CC BY 4.0) at: creativecommons.org/licenses/by/4.0/legalcode

If you do not agree to the terms and conditions you must not use the geospatial products.

You are free to copy, communicate and adapt the licensed material, provided that you abide by the licence terms (including Attribution) and attribute the licensed material using the statement:

Supplied by the Department of Environment and Natural Resources. Copyright Northern Territory Government.


Data Quality

Lineage:The weeds data is drawn from various datasets with differing accuracy levels. Each record is annotated with a unit of accuracy which is further described in the positional accuracy section. Attention should be given to the REC_METHOD (recording method) field as it also provides an indication of the survey method and subsequent limitations.

NT_weeds _absent dataset contains the date of the record of the named weed, which was searched for and not found. Two common reasons for recording absent record is when a weed has been known to occurred in that area previously and when an area is comprehensively searched to find the present and absent of the named weed. AVAILABLE TO THE PUBLIC ONLY WHEN REQUESTED.

Positional Accuracy:Positional accuracy is described by category for each record in the attribute "REC_METHOD". Within each category the actual accuracy will vary as described below.

Single GPS....................Handheld GPS, typically accurate to +/- 15m;
Averaged GPS...............Handheld GPS, held to average. Typically accurate to +/- 5m;
Differential GPS.............GPS or survey equipment using base station or other correction systems. Typically accurate to +/- 10 cm;
Prior Record...................Method of positioning unknown. Typically accurate to +/- 100m;
Topo Map Ref.................No longer used;
Hand drawn on map.......Digitised from a hand drawn map. Typically accurate to +/- 250m;
On-screen Digitised........Digitised on a GIS or Google earth background. Typically accurate to +/- 50m;
Road Survey..................Observation point using the roadside survey method is typically accurate to +/- 15m, however the observed area can be up to 250m;
Aerial Survey.................Observed point using the aerial survey method is typically accurate to +/- 15m; however the observed area can be up to 250m;

Attribute Accuracy:The majority of records have been created by authorised weeds officers and should be considered as highly reliable within the context of the method used. Other reliable sources include early weed databases which were created and maintained by primary industries officers, Herbarium records and vegetation plots maintained by Flora and Fauna Division, Department of Land Resource Management.

TAXONOMY, NAME CHANGES AND COMMON NAMES: Weed species are recorded with the taxonomic name which was valid at the time the data was submitted. The Weed Management Branch maintains a taxonomic table of NT weeds which includes aliases, name changes and defines the recognised application of common name to species.

SPECIES AGGREGATES: Some species eg: Mission grasses, Sporobolous' are very similar and a sometimes treated as a collective. 'Sp' refers to a collective where only one species of the collective is known to present but it was not determined which species eg: annual OR perennial mission grass is present ie: Mission grass sp.

MISSING DATE NOMENCLATURE: Records without an exact date are included in the recordset if they are deemed to be otherwise reliable. Where a year can be determined the date is represented as 1/1/19XX, where XX represents the year of the record (most such records are pre 2000, post 2000 records would appear as 20XX). For example, a record occuring some time in 1986 would be assigned 1/1/1986. Where neither the exact date or the year can be determined, the record would be assigned the date 1/1/1900. Where a record is known to be within a range of years, but the exact date is unknown, it should be assigned the date 1/1/1900 and can be commented to that effect if desired.
Note : No actual weed records have been recorded on the first of January in any year.

Logical Consistency:Not documented

Completeness:Complete


Contacts

NameOrganisationPositionRolePhoneFaxEmail
Data Requests OfficerDepartment of Environment, Parks and Water SecurityGeospatial Services Branch (on behalf of department)distributordatarequests.depws@nt.gov.au

Data Dictionary

AttributeAttribute DescriptionPossible CodeCode Description
1.1 INDEXDefinition: Unique record identifier, database generated.

Number is generated by hosting software and may be subject to re-indexing, cannot be relied upon as a reference to a record. The INDEX field is system dependent, may also be known as FID, OBJECT ID or ID.
1.2 SITE_ID Text (string), 15 characters
Waypoint ID or other similar source identifier for this record applied by the observer.

- This is not a unique identifier.
- The intention of this field is to assist in tracing a record back to its field observation source.
- Blank values can be entered. Null or empty string value designates no data value. Note that some software (including FME) is sensitive to null vs empty values and will require handling at application level.
1.3 SITE_MONText (string), 15 characters
Example DALY0001
Identifies spatially unique site with the intent of revisiting to monitor progress.

- This is not a unique identifier.
- Ideally, a monitoring protocol should be used in association with a site identified by this field.
- Blank values can be entered. Null or empty string value designates no data value.
- Note that some software (including FME) is sensitive to null vs empty values and will require handling at application level.
2.1 WEED_NAME Text (string), 40 characters

Common name of the weed species.
Example: Mimosa

Values are case sensitive; refer to Commonwealth government style guide for capitalisation standards.
2.2 GENUS_SPP Text (string), 60 characters

Scientific or Botanical name of the weed species ie Genus species.
Example: Mimosa pigra

Set Values: Required. Refer to Appendix A NT Weed Species listing for correct spelling conventions,

- Blank values are not acceptable
- Values are case sensitive
3.1 DATE_REC The date of the recorded observation. Note, record in format 1/1/2011 if the exact day/month is unknown

Format: DD/MM/YYYY
Example: 12/03/2005

- Blank values are not acceptable
- Record in format 1/1/2011 if the exact day/month is unknown
- Record in format 1/1/1900 if the date is unknown
4.1 LAT_G94 Number (Double)

Example: -13.02345
The latitude (Y coordinate, determines North - South), identifying the location of the weed infestation site. This must be entered in Decimal Degrees ideally to 5 decimal places (equivalent to 1 metre on the ground). The location should be recorded in the centre of the weed infestation, if possible.

- All data is stored using the datum GDA94. (Geocentric Datum of Aust 1994)
- For POLYLINE or POLYGON data the latitude is calculated for the centroid of the line
- Blank values are not acceptable
4.2 LONG_G94 Number (Double)

Example: 131.45761
The longitude (X coordinate, determines East - West), identifying the location of the weed infestation site. This must be entered in Decimal Degrees ideally to 5 decimal places (equivalent to 1 metre on the ground). The location should be recorded in the centre of the weed infestation, if possible.

- All data is stored using the datum GDA94. (Geocentric Datum of Aust 1994)
- For POLYLINE or POLYGON data the latitude is calculated for the centroid of the line
- Blank values are not acceptable
4.3 REC_METHODText (string), 25 characters
Method used to define the weed infestation location. Current set values should be used wherever possible, historical set values have been retained for compatibility with existing record.

SET VALUES:
Aerial spray
Aerial survey
Differential GPS
Onscreen digitised
High precision GPS
Itracker device
Low precision GPS
Not recorded
Corridor survey

RETIRED:
Averaged GPS
Hand drawn on map
Topo map ref
Single GPS
Topo map ref

- Blank values are not acceptable
- Some values within the set list are redundant ie: different list values represent the same level of accuracy. They are retained to allow users to enter values that are more intuitive than if they were listed by strict functional categories
- This field renames the PRECISION field in the previous standard; this is to avoid confusion with existing formal definitions for the term `precision' used in surveying and related fields.
5.1 RECORDER Text (string), 40 characters

Example: Phil Hickey
The name of the person responsible for capturing the weed data information. In the case of supervised teams the supervisor's name should be entered against the data. Check previous submitted entries to maintain consistency of name.

- Field RECORDER and ORG_NAME must not both be blank ie: RECORDER & ORG_NAME
- Where blank values are applicable, null or empty string value designates no data value. Note that some software (including FME) is sensitive to null vs empty values and will require handling at application level.
- Values are case sensitive
5.2 ORG_NAME Text (string), 50 characters

Example: Weed management branch
The name of the organisation submitting the weed data information Check previously submitted entries to maintain consistency of name of the organisation. Where the organisation is unknown or an individual is submitting data should the value should be entered as blank.

- Field RECORDER and ORG_NAME must not both be blank - RECORDER & ORG_NAME.
- Where blank values are applicable, null or empty string value designates no data value. Note that some software (including FME) is sensitive to null vs empty values and will require handling at application level.
- Values are case sensitive
6.1 SIZE_DIA_MText (string), 40 characters
Approximate diameter of the weed infestation area (using metres)

SET VALUES:
5
20
50
100
200 - Aerial surveys only
7.1 DENS_CATNumber (Integer), Short

Weed density is the estimated area occupied by the weed expressed as a percentage of the designated site area size, whether assessed by;
- surface area occupied (for aquatic plants, smaller grasses and herbs)
- projected canopy cover (for larger grasses, vines, tall shrubs and trees)

This information can illustrate changes in severity of weed infestations across the landscape over time.
Ref: p 20. McNaught, I. et al (2008) A field manual for surveying and mapping nationally significant weeds; Bureau of Rural Sciences, Canberra.

Set Values: 11 Density classes or categories

Category No and Description
1 Absent
2 < 1%
3 1 - 10%
4 11 - 50%
5 > 50%
6 Present but density unknown
7 Not known
8 Not assessed
9 Aquatic - scattered
10 Aquatic - 100% cover
11 Eradicated and monitored

- Where sites have been successfully treated but standing vegetation that can be positively identified remains ie: dead trees, bushes, or remnants of grass, the remaining dead vegetation should be assessed in the density category score.
- Blank values are not acceptable; data administrators should force all `no data', blank or null values to sentinel value -1. Take care to ensure sentinel values are not included in summary statistics.
7.2 TREATMENTText (string), 40 characters
Definition: What was the treatment applied today, if any?

SET VALUES:
No treatment
Unknown
Treated
Foliar spray
Residual application
Basal bark
Cut stump
Stem injection
Aerial spray
Slashed or cut
Burn
Hand pull
Shaded or covered
Combination treatment

This field should best describe the treatment applied to the weed area on the day the record is taken.
8.1 PROJECT Text (string), 150 characters
Project description, where work is carried out for a specific project.
Example: Daly catchment strategic mimosa control

- Care must be taken with project names to ensure they are entered consistently for each record, apply application level controls where possible
- Actual project names may contain punctuation characters which cause difficulties for GIS or database processing, users should be made aware of these restrictions and application level controls applied where possible.
- This field may cause update, addition and deletion data anomalies, apply application level controls where possible.
8.2 SEEDLINGS Text (string), 15 characters
Are seedlings present at the site?

SET VALUES:
Yes
No
Unknown
Not recorded
8.3 JUVENILESText (string), 15 characters
Are juveniles present at the site?

SET VALUES:
Yes
No
Unknown
Not recorded
8.4 ADULTSText (string), 15 characters
Are adult plants present at the site?

Adult plants include any plants which have produced seed. Adult plants also include any plant that has reached a size or appearance of maturity of being fully grown or likely to produce seed.

SET VALUES:
Yes
No
Unknown
Not recorded
8.5 SEED_PRESText (string), 15 characters
Are seeds present (visible) at the site?

SET VALUES:
Yes
No
Not assessable
Not recorded
8.6 PAST_TREATText (string), 15 characters
Is evidence of previous treatment impacts visible at the site?

SET VALUES:
Yes
No
Unknown
Not recorded
9.1 HERBICIDEText (string), 40 characters
What was the active ingredient(s) of the herbicide applied today, if any?

SET VALUES:
No treatment
Not recorded
Glyphosate
Glyphosate 360gL

Notes:This field renames the TREAT_CHEM field in the previous standards. This is to clarify the purpose of the field as recording active herbicide ingredients rather than brand names, adjuvants or other additives which are handled in other fields.
9.2 YEARText (string), 4 characters
The year the weed data was recorded
Format: YYYY Example: 2006

Record as value `1900' if the year is unknown
9.3 COMMENTSText (string), 150 characters.
- This field contains information about an observation or site relevant only to the data collector or their organisation.
- Comments should be restricted to information used in the short term such as aiding data entry, or reminding the observer to enter a file note or follow up with a landholder.
- No set values

Notes: Comments are an unreliable way to store information in the medium or long term as they are difficult or impossible to search or aggregate, and may become detached from the record in data entry or processing. Attribute fields, file notes or other comment management systems should be used in preference.
SYM_1Symbology 1 field represents the "TREATED" column information. This field is used for NR Maps symbology only.
SYM_2Symbology 2 field represents the "DENS_CAT" column information. Used only for NR Maps symbology

Supplementary Information

Further information about the application and limitations of weed data records is available by contacting the Weed Management Branch weedinfo@nt.gov.au
nt.gov.au/environment/weeds

This record maintained using the NTLIS Metadata Tool