Sample Placement Page for Presence/Absence Sampling

Sample Type

Size of Grid Cell

Length of side of square grid cell.

Grid Cell Units

Units associated with the size of the grid cell.

Composite Options

Composite Samples

Check this box to group the grid cell samples into composite samples

Samples per Composite

Maximum number of grid cell samples to include in each composite (note:  some composites may have fewer than this number of grid cells)

Maximum Distance

Individual grid cells that are farther than this distance away from a composite group will not be included with the composite group.

Maximum Distance Units

Units for the maximum distance between composites.

Placement Method

Simple random sampling

Places samples in sample areas in a random arrangement using the selected random number generator.

Systematic grid sampling

Places samples in sample areas in a systematic grid arrangement.

Random Start

Check this box to start the systematic grid at a random offset within the sampling surface.

Grid Type

Square

Use a square grid pattern for systematic grid placement.

Triangular

Use a triangular grid pattern for systematic grid placement.

Rectangular

Use a rectangular grid pattern for systematic grid placement.

Rectangle Width/Height

When using a rectangular grid pattern for systematic grid placement, this input specifies the width to height ratio of the rectangular grid.

Surface Selection

Use these options to choose surface types for sample placement:

All Surfaces

Default option. Choose this option to place samples on all surfaces, regardless of surface type. Will also place samples on surfaces that do not have a defined surface type.

Specific Surfaces

Choose this option to place samples on only selected surface types (see list below).

Surface Type List

Use this list to select which surface types to place samples. Any combination of surfaces can be selected.