Field Analysis:How Landscape

From SASSA

SASSA Home Page ⇒ Field Analysis Home Page ⇒ Field Recording ⇒ How? ⇒ Landscape

---

[edit] Background information

It can be useful to record local soil and parent material types as mapped locally. This information gives a general indication of the soil conditions that might be expected, for example if the soils locally are calcic evidence of calcium carbonate deposition in the site deposits may also be expected.

Information about the local parent materials can also be useful. For example if they are mapped locally as sands and gravels we can predict that the soils will also be free draining and prone to be acid through leaching. Information about parent material may be obtained from local soil and / or geology maps.

N.b. Because of the size of the sampling grid, soil and geology maps can be very inaccurate when trying to predict soil or parent material type at any specific location. Instead they give a general indication of what might be expected in the area.

[edit] Landscape information

For each site, section or set of deposits as appropriate general background information should be recorded. This includes:

• Drainage class
• Landscape position
• Slope and aspect
• Microtopography - small scale surface features such as hummocks and hollows.
• Local soil/geology/natural type
• Evidence of disturbance e.g. rabbits, gophers, earthworms, tree roots, earth movement
• Vegetation and land use
• Depth of deposit

[edit] Drainage class

Drainage class	Criteria
Poorly drained	Soil remains wet to a shallow depth, and excess free water is evident in the profile for long periods of time
Moderately drained	Water drains somewhat slowly due to impervious nature of substrate, low slope, and/or shallow water table
Well drained	Water drains easily but not rapidly. Free water is uncommon
Excessively drained	Water is removed from the surface very rapidly. Free water is very rare or very deep

Other indicators of drainage status can be the local vegetation a poorly drained soil may support sedges and rushes for example. Also look for iron mottling and blue/grey soil colours which can indicate poor drainage and periodic waterlogging.

[edit] Landscape position

Record the general landscape position of the site, for example Cave, Inter-tidal, Flood plain etc.

[edit] Slope

Record the slope angle either generally of the site, or locally with regards to a particular section or deposit.

• Level - less than 5^o
• Moderate - 5^o-10^o
• Steep - 11^o-35^o
• Precipitous - more than 35^o

[edit] Microtopography

Record the microtopography (small scale landscape features) in the immediate vicinity of a particular section or deposit. For example:

• Flat
• Slope
  • Straight
  • Convex
  • Concave
• Hummock or mound
• Basin or hollow

[edit] Disturbance

Record any evidence of disturbance. Whether from:

• Plant roots.
• Animals such as badgers, rabbits, termites, ants, earthworms etc.
• Slope movements (mass movements)
• Human activity
• Wetting and drying or freeze-thaw.