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Database Title	10.1 Aquatic Plants Database
Keywords Type1. Type 11.	Aquatic plants; lakes Macrophytes
Abstract	This contains a framework of 990 lakes with geophysical information from Irwin (1975). Aquatic plant data for 100 surveyed lakes forms the core of the database. Many of the lakes surveyed for aquatic plants have been revisited and so there are multiple entries for a number of lakes.
Geographical Coverage	New Zealand. NZ map grid is used to define position.
Dataset start date.	1978
Dataset end date.	Current
Status/currency.	In progress
Update frequency.	As new data becomes available. There is no regular pattern for resurvey work which is now client driven.

 

Technical Evaluation
Parameters- what is measured	For each aquatic plant species the following are measured: minimum depth and maximum depth maximum cover within a 2x2m square from anywhere within its range average cover within its range (cover is measured on a 6 point scale) maximum height of the species in the profile estimated average height of species in the profile. Site information (e.g. length of profile, sediment composition) is also collected
Parameters- what is calculated	For each lake: depth range for each species total number of profiles with each species minimum, maximum and typical depths for each species maximum and average cover for each species % dominance of exotic versus native species relative % cover of different species the stability of the plant communities stylised profiles of lake plant communities
Methods used to measure parameters	The rapid survey method as described in Clayton (1983).
Secondary sources of data	N/A
Scale of use.	N/A
Number of records	There are records for 100 lakes. This includes multiple records for some lakes.
GIS compatibility.	This is being investigated. Grid reference is identified at each site.
Available formats for users.	The data is stored on a Microsoft access database. Usually the data is made available by way of an interpreted report, rather than as raw data
Access constraints.	The database is generally available for NIWA staff only.
Measurement Accuracy	To be completed by database manager.
Completeness of dataset	Includes records for most accessible lakes with submerged vegetation as a significant component of the ecosystem.
Positional accuracy	Variable depending on whether sites were located by topographical feature (c. km for large lakes), or by GPS (c. 100m).
Database steward	NIWA
Database custodian	NIWA
Database custodian contact person	Mary de Winton
Database custodian Contact Address Phone Fax Email	P.O. Box 11 115 Hillcrest Hamilton +64 7 856 7026 +64 7 856 0151 m.dewinton@niwa.cri.nz
References	Clayton, J.S. 1983. Sampling freshwater macrophyte communities. In: biological methods for water quality surveys. Water and Soil Technical Publication 54. Irwin, J. 1975. Checklist of New Zealand lakes. Oceanographic Institute Memoir 74
Date metadata record prepared.	October 1999
Author of metadata record.	Victoria Froude

 

Management Evaluation
Original purpose.	To centralize records; and to standardize data collection, data entry and interpretation for aquatic plant data. The database provides a reliable way to assess changes in aquatic plant distribution / relative abundance.
Relationships with classification systems.	N/A
Relationships with other databases	N/A
Known relationships with proposed EPIP indicators.	N/A
Who uses this database?	NIWA staff. Clients who have management responsibilities/interests in water bodies (DOC, regional councils).
Public awareness of the database	Low
Database strengths.	reproducibility of data data has been collected using standard methods much useful historical data was collected when there was public funding for data collection good time series data that shows changes for a number of lakes. This includes documenting alien invasions and the decline of many lakes
Database limitations.	only addresses lakes only includes lakes that can be driven to or require only a relatively short walk (exceptions: Lakes Poteretere and Lochnagar). some lakes have only limited records specialized knowledge is required to interpret the data on the database as resurvey and new survey require a client there is now a considerable reduction in the data being entered into the database

 

What are the Current and Emerging Uses of the Database for:
Assisting with determining historic state/baseline.	The database can be used to reconstruct vegetation patterns in lakes. It can also be used to show change over the period of records for a particular lake.
Assisting with determining current state/baseline.	The database is used extensively to describe the current situation with aquatic plants in lakes.
Assisting with modeling possible future outcomes.	The database can be used to model changes in characeans for New Zealand and within a specific water body given particular levels of alien plant invasions.
Risk assessment.	The database can be used to identify risks associated with alien plant invasions and the decline in lakes dominated by alien plant species.
Monitoring site selection and sample design.	The database can be used to identify representative sites.
Aggregating and reporting data locally, regionally or nationally.	Data can be reported by lake and nationally. It can also be reported for most regions. There is a lack of information in some regions, e.g. Southland.