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Soils are tested and monitored for a variety
of reasons and to answer specific questions.
Tests can help identify and assess soil
constraints, for example the soil texture and
pH, which can not easily be changed. Tests
can also be used to identify changes due to
management decisions over the short- or
long-term. Ask yourself: What functions are
you interested in: Water storage/movement?
Carbon storage/cycling? Nutrient cycling?
Erosion resistance? Disease and pest
suppression?
Soil tests can be qualitative or quantitative.
You gain considerable insight into your soil by
digging a hole and looking at the soil’s color,
looking for signs of life, smelling the smells,
and feeling the texture and moisture. These
are qualitative assessments.
Quantitative tests include, for example,
lab tests for nutrient availability, assays of
microbial abundance and activity level, and
weighing the amount of biomass in a clip
plot. Both qualitative and quantitative tests
are useful and important, but sampling
design plays an enormous role in how useful
the information will be for answering your
questions.
Different agencies and granting entities, and
emerging carbon and ecosystem service
markets, will require slightly different soil
analyses. Treat the protocols and suggestions
in this workbook as a jumping-off point,
but certainly follow whatever directions are
needed for the specific case.
After completing this section
you will be able to:
•
Evaluate goals of sampling to
decide the spatial/temporal extent
of sampling/observing
•
Evaluate goals of sampling to decide
on soil, water, and biological lab tests
•
Know where to find soil classifications
using the USDA Web Soil Survey
•
Identify considerations for how to
sample soils, water, and biological
material to send for lab testing with
consistency
Learning Outcomes
3. Basic Soil Monitoring
and Evaluation