Sample Placement Page

This page of the sample design dialog controls how samples are placed on the map.

This design page contains the following controls:

(Note: Not all of these controls will be active or visible for every sampling design.)

Sample Type

 

Point Samples

Use sampling locations that represent a single point.

Grid Cell Samples

Use sampling locations that represent a square area (grid cell).

Size of Grid Cell

Length of side of square grid cell.

Grid Cell Units

Units associated with the size of the grid cell.

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 sampling in grids

Places a square grid over the entire site and randomly places samples within the square grids.

Adaptive grid sampling

Places a rectangular grid over the entire site and places samples at an offset within the grids.

Include Historical Samples

Check this box if you want to include existing sample locations as part of this sample design.

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.

Z Placement

When placing samples in a 3D sample area:

Random

Use a random Z coordinate.

Random on Layers

Randomly choose a Z coordinate from the Layer Z grid.

On Each Layer

Place one sample at each Z coordinate in the Layer Z grid at each location.

3D Square Grid

Arrange samples in a (X, Y, Z) square grid throughout the entire 3D space.

Surface Only

Place samples only on the top surface of the 3D space.  (Most useful for sample areas with mapped elevations.)

Layer Z grid

Enter Z coordinates to be used for Z placement options 2 and 3.

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.