Special Concerns
Are There any Special Concerns When Measuring Soil Variables?
Soils respond to changes over longer time scales than most other components of forest ecosystems. Diurnal and seasonal variations in soil chemistry are not a concern for the types of chemical and physical analyses conducted in this program. However, determination of soil chemical variables in the laboratory can be highly method dependent. Use of FIA laboratory data with other soil information requires careful consideration of the analytical procedures used. Erosion and compaction measurements are based largely on the properties of the soil surface. Any site condition that obscures the forest floor can affect collection of soil data, including: (1) standing water; (2) snow; (3) recent leaf drop; (4) trampling or other disturbance by the field crews. These effects are minimized by thorough training and strict adherence to data collection procedures.
A document, "Soils as an Indicator of Forest Health: A Guide to the Collection, Analysis, and Interpretation of Soil Indicator Data in the Forest Inventory and Analysis Program," was recently published. This companion to the field guide documents the types of data collected as part of the FIA Soil Quality indicator, the field and laboratory methods employed, and the rationale behind these data collection procedures.
National Historic Preservation Act
Federal regulations apply to the collection of soil samples in areas
with historical or cultural artifacts (National
Historic Preservation Act of 1966). If crews encounter artifacts
on a soil sampling site, they do not collect any samples. Instead,
the site is coded as "not sampled" and an explanation recorded
as part of the plot notes.
Animal and Plant Health Inspection Service
(APHIS)
Crews
working in certain areas need to be aware of government regulations
regarding the shipping of soil samples through the mail. Some soils
contain pests such as fire ants or golden nematodes that could seriously
impact agricultural production. To limit the movement of these pests
in the U.S., there are government regulations regarding the shipment
of samples from affected areas (shaded) to non-affected areas (white).
Each of the regional soil laboratories in the FIA program have been certified by the USDA to receive regulated soil samples.
APHIS
regulated counties (pdf 138K)
APHIS
regulations
Last Modified: 03/01/2007