The effectiveness and applicability of the Soil Management Assessment Framework (SMAF) was tested by applying it to numerous research results. The results from four case studies are shown here. Each of the case studies differs in region, climate, soil, land-use practice, and management goals. The sites were: the 1996 Natural Resource Inventory (NRI) MLRA 9 spanning parts of Idaho, Washington and Oregon; the Deep Loess Research Station near Treynor, IA; the Sustainable Agriculture Farming Systems (SAFS) project near Davis, CA; and two experiment stations in Georgia near the cities of Calhoun and Farmington.
Case Study Descriptions | ||||
---|---|---|---|---|
Property | NRI | Treynor | SAFS | GA Exp Station |
Scale | MLRA 9 | watersheds | large plot | small plot |
State(s) | ID, WA, OR | IA | CA | GA |
Treatment | multi | conservation tillage | system | compost |
Data type | chemical, biological | chemical, biological | mostly chemical | chemical, biological and physical |
Published | yes | no | yes | some |
Soil suborder | Xerolls, Albolls | Udolls, Orthents | Fluvents, Orthents | Udults, Udalfs |
Management goal | environment | production | production | manure management |
The inherent properties and management goals (and the available data) for each study site dictated the choice of indicators:
Case Study Indicators | ||||
---|---|---|---|---|
Assay | NRI |
Treynor |
SAFS |
GA Exp Station |
Available water capacity | X |
|||
Bulk density | X |
X |
||
Electrical conductivity | X |
|||
Microbial biomass C | X |
X |
||
Mean weight diameter | X |
X |
||
Soil reaction (pH) | X |
X |
X |
X |
Potentially mineralizable N | X |
X |
||
Metabolic quotient | X |
|||
Sodium adsorption ratio | X |
|||
Soil test P | X |
X |
X |
|
Total organic C | X |
X |
X |
X |
Each of these was compared with end point data as available.