assessment, inventory and monitoring: introduction …...2016/04/08 · soils: genesis and...
TRANSCRIPT
Introduction to Soils and
Ecological Sites
Presented by: Sarah LamagnaEcologist, NOC
Why gather soils info?
1953 1956 2010
We’re monitoring change over time
Soils help us understand landscape change
Soils help differentiate ecological sites
Ecological Sites
A kind of land, defined by its soils, topography and climate that:
1) potentially produces similar kinds and amounts of vegetation
2) responds to disturbances and drivers similarly (e.g., grazing and rainfall)
So what are the steps in identifying ecological sites?
1. Gather information in office
• Key to Ecological Sites• Topographical Map
• Soil Map• Soil Map Unit Descriptions
• Ecological Site Descriptions (ESD’s)• Climate information
Web Soil Survey
Ecological Site Descriptions
• Based on soil map units
• Each soil map unit matches up with one or more ecological sites
2. Go to the field
• Navigate to your site.• Find out where you are on the maps.
• According to the soil map units in the area, what ecological site(s) could you be on?
3. Compare physical characteristics – DIG A PIT!
• Do you have the same topography as the ESD?• Are you at the same elevation as the ESD?
• Are the soil properties (esp. texture) the same as described in the soil map unit component and
associated ESD?
4. Compare vegetation
• What plants are on the site?• Which state or community are you in?
What exactly goes in to digging a soil pit?
A soil scientist helps!!!
Bulk Density
Structure
Color
What soil properties does AIM require you to measure?
Texture
Soil Horizon Depth
Effervescence
Coarse Fragments
Percent Clay
Structure
Color
Bulk Density
Soil Profile Data Sheet
Part of Plot Characterization Data Sheet
Match each soil property with its corresponding reason for collecting it
Texture
Horizon Depth
Effervescence
Coarse Fragments
Percent Clay
Affects all soil processes and one of the most important soil properties
Indicator of calcium carbonate content
Important in understanding the processes of water infiltration and availability, soil stability/erodibility, and plant rooting
Affects soil water availability through infiltration, storage, and evaporation
Describes entire soil ped to help determine ecological site ID
Color
Structure
Affects soil water availability through depth that water can penetrate and residence time that water is available to plants
Indicator of the amount of organic matter which is important for water holding capacity and nutrient availability
How many horizons do you see?
What are the differences in soil
properties between horizons?
How many horizons do you see in each soil pit?
Sandy Site Loamy Site
How many horizons do you see in each soil pit?
Sandy Site Loamy Site
Sandy Site Loamy Site
What differences in soil properties can you see?
What differences in soil properties can you see?
Sandy ClayLoam
SandyLoam
Sandy Clay Loam
Calcic w/ ~20% CaCO3
LoamySand
Fine Sandy Loam
Sandy Site Loamy Site
Calcic
Petro-calcic
How many horizons do you see in each soil pit?
How many horizons do you see in each soil pit?
What differences in soil properties can you see?
What differences in soil properties can you see?
LoamySand
Calcic w/ ~20% CaCO3
Sandy Loam
Silty ClayLoam
Silt Loam
LoamySand
LoamySand
LoamySand
Soil profiles common to Oregon
A horizon -High OM
Clayey
Welded tuffCompaction
VERYCommon
Soil profiles common to Oregon
Ash
Vertic Clay
Vertic ClayWeaker Structure
Welded Tuff
VERYCommon
Soil profiles common to Oregon
Ash
Vertic Clay –High Rock Fragment %
Welded Tuff
VERYCommon
Soil profiles common to Oregon
Ash
Vertic Clay
Vertic Clay –Color change
Soil Texture Flowchart
Soil and ecological site resources
• Web Soil Survey
• SoilWeb App for iPhone and Android
• Soil Series Descriptions
• List of Published Soil Surveys
• Approved Ecological Site Descriptions
• LandPKS App for Site Characterization
For more soil background info:
Field Book for Describing and Sampling Soils –plus video on how to use it
Factors of Soil Formation – classic book by Hans Jenny available online
The Nature and Properties of Soils – book to purchase that provides a clearly written, general overview
Soils: Genesis and Geomorphology – textbook to purchase
Getting your hands dirty will help!
Questions?