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Part 9: Collecting Monitoring Data
Setting up Your Data Collection Locations
There are several methods that can be used to establish data
collection (or study) sites when monitoring rangelands, regardless
of which attribute you are monitoring. The methods described below
can be used with each of the monitoring methods described in this
module and include Baseline Layout, Linear Layout, and Block Layout.
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Baseline Layout – A baseline is established
by stretching a tape measure of a certain length between two
marker posts. These stakes are separate from the study marker
stake that is used to find your monitoring location year after
year. They are generally placed 50-200 meters apart.
- Transects – individual transects
are then run perpendicular to this baseline. These transects
are located at random locations along the baseline and can
be located by measuring distinct distances, or by marking them
with a certain number of paces between each. Transects can
be run on either side of the baseline with the baseline running
down the center, or on all one side with the baseline forming
the outer boundary of the sampling area. To ensure that transects
are randomly determined, decide before you go to the field
how you will establish transect locations (distance between
each transect and on which side of the baseline they will be
located).
- Quadrats or observation points – Quadrats
or observation points are located at regular intervals along
the transects. Often they are placed at each pace.
- Unusual areas – Design of the baseline
and transects may need to be modified for long, narrow areas such
as riparian areas. A single, long transect may be more suitable
(see Linear Layout below).
- Linear layout – This type of study
site is laid out in a straight line. This arrangement is designed
for long, thin sites such as along riparian areas.
- Permanently mark the site at the beginning of the transect
with a stake.
- Mark the end of the transect by placing a stake or by identifying
a permanent landmark (such as a peak, rock, etc.).
- Set quadrats along the length of the transect where measurements
can be taken, usually at each pace or so. For example, you
can set quadrats every 5 feet, or every 3 steps. Quadrats can
also be set at randomly measured or paced intervals.
- Additional transects can be set in different directions
from the same beginning point stake forming a star-shaped layout.
-
Block layout – This study design
can be many different shapes and sizes. The discussion
presented describes a set-up containing 25 paces and a square
design. This can be altered to accommodate your needs.
- From your initial site marker post, step two paces to the
right.
- From this point, proceed forward 25 paces, taking quadrat
readings at every pace.
- Turn 90 degrees left and walk 25 paces, taking quadrat readings
at every pace.
- At 25 paces, again turn left 90 degrees.
- Continue in this fashion until the square has been completed,
collecting frequency data at every pace.
- The number of paces taken will depend on the study site
and the ultimate size and shape of the transect.
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