Aquatic Riparian Effectiveness Monitoring Program (AREMP)

The Aquatic Riparian Effectiveness Monitoring Program (AREMP) was established under the Northwest Forest Plan and samples BLM and USFS watersheds with >5% federal ownership in the coast range of Washington, Oregon, and California. NAMC developed an O/E and MMI index for AREMP in 2014 using interagency data. To calculate the AREMP indices, macroinvertebrates should be identified to NAMC’s standard taxonomic resolution and collected May 1 - September 30.

Map or western U.S. with black dots scattered along the coast
AREMP macroinvertebrate reference sites

Index Precision and Benchmarks

Index # reference sites # degraded sites Index mean Index SD Moderate departure from reference benchmark Major departure from reference benchmark Narrative conditions
AREMP OE 202 NA 1.0191 0.148 <= 0.871 <= 0.724 Good, Fair, Poor
AREMP MMI 200 166 0.68 0.10 <=0.53 <=0.49 Good, Fair, Poor

Box plots of catch elevation(m) on a scale of 0 to 2500 with a mean of 1000, mean annual precipitation (mm) on a scale of 500 to 5000 with a mean of 2000, temperature (C) on a scale of 0 to 15 with a mean of 7 and log watershed area (km2) on a scale of -1 to 3 with a mean of 1
Environmental gradients of reference sites used to develop AREMP indices and used for NAMC’s model applicability test

AREMP O/E

  • Method for accounting for natural environmental gradients: Random forest model predicting group membership
  • Predictors of reference assemblages or metrics:
    • Maximum elevation in the watershed
    • Mean elevation across the watershed
    • Average of minimum precip at the watershed
    • Watershed mean of mean 1971–2000 annual maximum monthly temperature
    • Area of the watershed in sq km
  • # of Macroinvertebrate groups obtained by hierarchical cluster analysis: 12
  • Fixed count: 300
  • Minimum count: unspecified
  • Operational Taxonomic Unit (OTU) applied: Yes
  • Rare taxa <0.5 probability of capture included: Yes
  • Documentation

AREMP MMI

  • Method for accounting for natural environmental gradients: Random forest model predicting individual metrics
  • Predictors of reference assemblages or metrics:
    • Mean elevation across the watershed
    • Minimum elevation in the watershed
    • Soil Erodibility across the watershed
    • Precip min at the point
    • Average of minimum precip at the watershed
    • Watershed mean of mean 1961-1990 annual relative humidity
    • Watershed mean of mean 1971–2000 annual maximum monthly temperature
    • Temperature mean at the point
    • Average of mean temperature at the watershed
  • Metrics used
    • # clinger taxa
    • % EPT
    • # Diptera taxa
    • % intolerant
    • # non-insect taxa
    • # long lived taxa
  • Fixed count: 300
  • Minimum count: unspecified
  • Operational Taxonomic Unit (OTU) applied: Yes
  • Rare taxa <0.5 probability of capture included: Yes
  • Documentation