GV003
Vegetation and microsite erosion relationships in the Mount St. Helens volcanic area

CREATOR(S): Frederick J. Swanson, Alisa L. Gallant

PRINCIPAL INVESTIGATOR(S): Frederick J. Swanson

ORIGINATOR(S): Alisa L. Gallant

OTHER RESEARCHER(S): Joseph E. Means

DATA SET CONTACT PERSON: Frederick J. Swanson

ABSTRACTOR: Alisa L. Gallant

METADATA CREATION DATE:

23 Jun 2005

MOST RECENT METADATA REVIEW DATE:

19 Dec 2012

KEYWORDS:

habitats, ecology, disturbance properties, regeneration, disturbance, revegetation

PURPOSE:

Inventory of microsites on clearcut and downed forest hillslopes of Mount St. Helens Blast Zone.

To obtain average areas (for stumps and rootwads) and dbh's (for snags) of certain microsites for each hillslope site.

To obtain areal vegetation cover by species, by microsite substrate, by shade class for each plot.

METHODS:

Experimental Design - GV003:

Description:

Type I: 15-meter plot transects are broken down to % length in each microsite type. Total length, by microsite, is also broken down into % by surface condition and shade class.

Type II: 6 x 15 m sq. belt transect at each plot (centered along 15 meter microsite transect measured in Type I data set) is sampled for area/dbh of stumps, rootwads, and snags.

Type III: 100 m sq. circular vegetation plot (Plot center correlates with transect centers for Type I and II). Determine m sq. coverage per species by microsite, shade class, and surface condition.

Field Methods - GV003:

Description:

Type I: Microsites are measured to nearest cm. along a 1-meter transect for each plot. Whether or not the microsite was shaded is also recorded.

Shade classes:

1. Shade from within 10 cm from microsite surface
2. Shade from 10-30 cm above microsite surface
3. Shade from >30 cm above microsite surface

Surface condition classes:

1. Coarse Pumice present
2. Coarse Pumice not present
3. Pre-eruption surface exposed
4. Mixture of pre-eruption soil surface and new deposits

Type II: Measurements are taken to the nearest cm. For microsites falling greater than 50% within the belt transect.

Type III: Vegetation is measured to nearest cm. sq.

SITE DESCRIPTION:

Volcanically disturbed hillslopes. Disturbance included heat (to greater than 200 deg. C) and burial (coarse to fine tephra; centimeters to meters of burial).

TAXONOMIC SYSTEM:

None

GEOGRAPHIC EXTENT:

Southern Washington Cascades, Mount St. Helens Blast Zone.

ELEVATION_MINIMUM (meters):

ELEVATION_MAXIMUM (meters):

MEASUREMENT FREQUENCY:

twice

PROGRESS DESCRIPTION:

Complete

UPDATE FREQUENCY DESCRIPTION:

notPlanned

CURRENTNESS REFERENCE:

Ground condition