Title

Port Phillip Bay 1:25,000 Seagrass 2000 

Alternate title

SEAGRASS_PORT_PHILLIP_BAY_2000 

Purpose

SEAGRASS_PORT_PHILLIP_BAY_2000 is a 1:25,000 layer that represents spatial extent, species distribution and density of seagrass and other aquatic vegetation within Port Phillip Bay. This layer forms part of a baseline survey of seagrass within Victoria. Ecological research into the health of seagrass meadows requires the type of detailed information collected in this baseline survey. 

Credit

David Ball and Penny Morris 

Supplemental Information

Relationship to other Datasets: The landward boundary of the layer corresponds to the 1:25,000 coastline (SHORE25). The coastline is subject to change especially in areas subject to erosion or mass movement of coastal sediments and at the entrance to the inlets. This layer forms part of a State-wide program to map seagrass throughout Victoria. Other seagrass layers exist for Gippsland Lakes, Corner Inlet/Nooramunga, Western Port and minor inlets of eastern Victoria (originally planned as a single layer, but now separated into individual layers for Anderson, Shallow, Sydenham, Tamboon, Wingan and Mallacoota Inlets). Current Design Issues: This information represents a "snap-shot" in time of the spatial extent of seagrass meadows in Port Phillip Bay. The area of coverage and density of the various species of seagrass changes with time, both seasonally and yearly. Future Design Issues: These may include adding extra species and recording the condition of the seagrass in relation to epiphyte coverage. Related Documents: None 

Status

Completed  

Horizontal Accuracy

25m  

Code

4283 

Maintenance and update frequency

As needed  

Topic category

• Biota

Use limitation

. 

Classification

Unclassified  

Statement

Dataset Source: 1:20,000 Colour Aerial Photography enlarged to a scale of 1:10,000 Photography flown on 25th and 31st March 2000, and 2nd and 3rd of April 2000. Dataset Originality: Primary 

Description

Collection Method: Remote Sensing - Aerial Photography, Field Measurements 

Description

Source description not available 

Description

The delineation of the seagrass meadows was conducted through Aerial Photograph Interpretation. The linework was digitized from stable base overlays plotted on 1:10,000 colour photo prints. Polygons were attributed with species and density from data collected at sample sites in the field (see PPB_SEAGR25 Field Work layers). Polygons were ground-truthed in the field by direct observation of the seabed from a submersible pod in small vessel. 

Classification

Unclassified  

Attribute Quality

Comments

All attributes have been verified by DPI Queenscliff, and are complete. 

Positional Accuracy

Comments

Horizontal accuracy ranges from 5 to 10 metres. 

Conceptual Consistency

Comments

Attributes checked by DPI Queenscliff 

Missing Data

Comments

This layer is complete for Port Phillip Bay 

Excess Data