1. Soil and Ecosystem Dynamics in Soil Survey
Susan Andrews, Ph.D. Ecology
NRSC NSSC National Leader
Soil Quality and Ecosystems
June 17, 2013
NRCS

2. Three Main Areas of Responsibility:
Soil Quality (SQ)
Dynamic Soil Properties (DSPs)
Ecological Sites (ESs)
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250

3. 1. Soil Quality in Soil Survey
NRCS Soil Health Initiative
SQEB has technical development responsibility
Emphasis on decision support and assessment tools

4. Soil Quality Definitions
“capacity of the soil to function”
- Karlen et al. 1997
Taken together this means that SQ is the ability of a soil to perform the functions necessary for its intended use.
“fitness for use”
- Larson & Pierce, 1991

5. Kinds of Soil Quality INHERENT SOIL QUALITY DYNAMIC SOIL QUALITY
after Pierce and Larson, 1993
reflects natural characteristics
based on soil forming factors
climate, parent material, topography, and biota, all acting over time – Jenny, 1941
describes status or condition of soil
result of land use or management practice

6. Relative Assessment Soil Function Soil A Soil B Dynamic SQ
Inherent SQ
Dynamic SQ
50%
85%
Dynamic SQ
with respect to Inherent capability
Soil Function
Soil A Soil B
- After Andrews et al., 2004

7. Soil Health v. Soil Quality
Soil health is used as a synonym for soil quality Doran and Parkin, 1996
Minor exceptions:
Health often includes only dynamic quality
Health some greater emphasis on biology
Dynamic and inherent soil quality will be covered in more detail in lesson 2.
A soil may have poor inherent soil quality
but still have good soil health.
Gregorich and Carter, 1997

8. Improvement of Kits and Guides
This chart shows recommended SQ Test Kit indicators to use for analyzing the soil’s ability to perform specific soil functions (in Arid & Subhumid Regions) There is a slightly different set for humid regions.
When doing a follow up evaluation, it is important to choose the appropriate tools and tests to perform.

9. Soil Health RAT Tool to assess soil health, by:
Selecting simple indicators
Interpreting results
Based on function
WRT inherent soil properties
Providing basic management advice
Part of the CDSI Mobile Planner
Will beta-test MS Access version

10. Soil Quality Priorities
Develop tools and interpretations
Revision of test kits and guides
Identify and interpret effects of soil function
Simple tools for conservation planning (RAT)
Advise the Soil Health Management Initiative
Inform trainers & others of the latest science
Inform farm bill policy

11. 2. Dynamic Soil Properties in SS
Millennia
An inventory of soil change over the human time scale, due to: - human management - natural disturbance
Decades and less - the management time scale
Decades to centuries - the recovery time scale
-Tugel et al., 2005
Centuries
First, I would like to read a quote that summarizes soil change. This is from Dan Richter and his co-author Dan Markowitz. In their new book, Understanding Soil Change. They describe “how soils change through time….soils are formed by pedogenesis, affected by land-use history, and are currently changing in modern ecosystems that have increasing human influence.”
Richter and Markowitz , Understanding Soil Change.
Decades
-Richter and Markowitz, 2001

12. Improve Accuracy of SS Databases (and provide reference values for SQ indicators)
Soil organic matter
Soil
Database estimate
Grassland-
measured
Cultivated-measured
Aksarben
2-4 %
6.0
3.0
Monona
3.6
2.9
(Grossman, unpublished)
Important for C-sequestration, water holding capacity, agg. stability, pesticide applications, nutrient applications

13. Develop Interpretations of Management Effects on Soil Function
The importance of soil change is its affect on function.
The consequences of change depend on its reversibility. (Arnold et al.,1990)
Land degradation
Illustrate applications and interpretations with examples.
Productivity
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Land use impacts

14. Differences in Resistance and Resilience
Soil with
high resistance
Soil with
low resistance
and high resilience
Soil with
low resistance
and low resilience
Soil Function
The distinction between resistance and resilience can be illustrated in an example using soil functions related to soil physical properties on an annual time scale. In temperate regions, many surface soils are resilient with respect to porosity changes following compaction. Frost action may serve as a recovery process. However, some soils are inherently resistant to porosity changes following compaction. These resistant soils can maintain their functioning capacity (e.g., hydrologic functions) at a higher level throughout the year than those which have a lower resistance but are resilient on an annual time scale.
Time (years)
Compaction
Disturbance
-Seybold et al., 1999

15. Main DSP Priorities Identify best ways to inform conservation
Develop new methodologies to rapidly populate the database
Models and pedotransfer functions
Validation sampling design
Hire postdoc for data mining and modeling
Sampling, assessment & analyses training
Standards and database requirements

16. 3. Ecological Sites in Soil Survey
Partnership with S&T Ecological Sciences Division and National Grazinglands Team
New standards follow basic MLRA planning
Soil Survey offers procedures for control and assurance and the correlation process
To succeed, we (NCSS) must work in interdisciplinary teams

17. Ecological Site Definition
An ecological site is a distinctive kind of land based on:
recurring soil, landform, geological, and climatic characteristics that differs from other kinds of land
in its ability to produce distinctive kinds and amounts of vegetation, and
in its ability to respond similarly to management actions and natural disturbances.

18. State-and-Transition Definitions
STATE - a recognizable, resistant and resilient complex of two ecosystem components: the soil base and the vegetation structure
- Soils help determine the site’s capabilities
- The interaction between soil and vegetation determines the functional status of the site and it’s inherent resistance to change.
Time
Vegetation attribute(s)
“Steady” States
Stringham, et al., 2003

19. State-and-Transition Definitions
TRANSITION - the trajectory of a change
- change is precipitated by natural events, management actions, or both
- degrades the integrity of one or more of the state’s primary ecological processes beyond the point of self-repair
THRESHOLD – boundary in space and time between two states
- irreversible for practical purposes
Time
Vegetation attribute(s)
thresholds
transitions
Note when explaining this slide, that thresholds often represent the point when a system function or process has changed so much that the system can no longer retain its current structure and changes to another state where new functions and processes are occurring.

20. Post oak/blackjack oak/little bluestem ESD, Missouri
State-and-Transition Model
Hot summer burn and /or long-term grazing
Burn, Site prep & Planting / Seeding.
No grazing or limited controlled grazing
Post oak/buckbrush (or similar) Lacks mid-story. Understory single species woody dominated
Canopy: open 30-90%
Post oak/flowering dogwood/ tick trefoil-goldenrod. Multi-story. Canopy: %
Harvest, site prep, seeding
Post oak/blackjack oak/little bluestem ESD, Missouri
Abandonment for 20+ yr with recruitment of woody natives
Westoby, et. al., 1989
Stringham et.al., 2001
Pasture (improved)
Non-native grass sod

21. Working Definition of a Agroecological Site
An agroecological site is a subset of an Ecological Site (ES) based on:
recurring soil, landform, geological, and climatic characteristics that differs from other kinds of land (within one ES)
in its potential to support distinctive ranges of soil functions (as indicated by dynamic soil properties), and
in its ability to respond similarly to management actions and natural disturbances.

22. Land Management Optimization (LMO) Model
Grain Rotation
Agricultural Production Groups
within an Agroecological Site
Forage Crops
Root Crops
Vegetable Rotation
High
Attainable for Forage Crops Production Group
Ecological Potential
Attainable for Grain Rotations Production Group
Degradation / Resilience Threshold
Resource Concern / Function Threshold
Soil Functions / Ecosystem Services
Native / Naturalized Plant Communities
This system allows for data collection, organization and presentation from both managed systems and traditional ecological sites for native or “naturalized” plant communities.
Low
Native/
Naturalized States

23. Land Management Optimization for one Production Group
Ecological Potential
Attainable for Grain Rotations Production Group
Grain Rotations
Rotation, low-till, no cover crops
Organic system w/ cover crops
Monocrop,
Deep tillage
Continuous
no-till w/ cover crops
Diverse rotation, tillage
Soil Functions / Ecosystem Services
Resource Concern Threshold
This system allows for data collection, organization and presentation from both managed systems and traditional ecological sites for native or “naturalized” plant communities.
Degradation / Resilience Threshold
Disturbance
within one Agricultural Production Group

24. Main ES Projects and Priorities
ES Policy and Standards (final revisions)
Database Requirements (review stage)
ES for Additional Land Uses
Crop (pilot stage) & pasture (planning stage)
Riparian (review stage)
Wetlands, Subaqueous (new, some work)
Development of Hierarchical Classification
Training, Communications and Outreach

25. Comments
and Questions?
Contact: