Soil Conservation Monitoring:

1
Soil Conservation Monitoring

• Forest Practices Code of
• British Columbia

2

• How are allowable levels of soil disturbance set
  for a cutblock?
• How is compliance assessed?

3
Definitions

• Permanent vs. temporary access structures (e.g.
  roads, landings)
• Permanent access up to 7 of block
• Temporary access can exceed soil disturbance
  limits by 5, but must be rehabilitated

4
Definitions

• Soil disturbance features
• unrehabilitated temporary trails
• corduroyed trails
• compacted areas
• dispersed disturbances
• ? can occupy up to 10 of block area, depending
  on site sensitivity

5
Silviculture Prescriptions

• SP is lowest-level plan ? submitted for each
  cutblock by forest licensee on Crown land
• Must specify
• site sensitivity
• seasonal or site constraints to forest practices

6
Hazard Assessment Key Guidebook

• Uses site and soil information to rate site
  sensitivity (L, M, H, or VH) for 3 major hazards
• compaction and puddling
• soil displacement
• soil erosion

7
Compaction and Puddling Hazard

• Based on
• texture
• coarse fragments
• moisture regime
• presence of thick forest floors or organic soils

8
Soil Displacement Hazard

• Based on
• slope gradient and complexity
• depth to root-restricting layers or adverse
  chemical properties (e.g. carbonates)

9
Soil Erosion Hazard(for exposed mineral soil,
not roads ditches)

• Uses similar factors to USLE
• precipitation/snowmelt regime
• slope gradient, length, uniformity
• soil texture, structure, coarse fragments,
  impervious layers

10
Most limiting hazard determines

• allowable level of soil disturbance (higher
  hazard ratings ? less allowable disturbance)
• which soil disturbance features are included
  during assessment of compliance (i.e. certain
  features are only counted on more sensitive sites)

11
Seasonal Constraints

• Based on local experience and/or research
• example on sites with H or VH compaction
  hazard, SP could restrict harvesting to dry or
  frozen ground, or adequate compressible snowpack

12
Assessing Disturbance

• 1. Visual inspection is anything obviously
  wrong?
• locations dimensions of roads, landings
• completion of TAS rehabilitation
• areas of concentrated disturbance

13
Assessing Disturbance

• 2. Formal compliance survey (seldom needed)
• roads landings traverse survey with hip-chain
  (length width)
• soil disturbance can be assessed for selected
  areas gt 1 hectare uses transect surveys which
  tally occurrence of features

14
Transects for small strata (lt 10 ha)

• parallel closely-spaced transects giving at least
  500 regularly-spaced observation points per
  survey stratum

15
Transects for larger strata (gt 10 ha)

• pairs of randomly oriented 30-m transects (at
  90) from origin points arrayed in a regular grid
• disturbance features recorded at 1-m intervals on
  transects

16
Does survey indicate compliance or non-compliance?

• For both traverse and transect surveys, calculate
  confidence limits
• Decision rules based on LCL non-compliance if
  Lower Confidence Limit of survey is above
  allowable levels set in Silviculture Prescription