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

Three Main Areas of Responsibility: Soil Quality (SQ) Dynamic Soil Properties (DSPs) Ecological Sites (ESs) 103 250

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

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

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

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

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

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.

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

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

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. 2001, Understanding Soil Change. Decades -Richter and Markowitz, 2001

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

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 103 250 Land use impacts

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

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

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

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.

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

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.

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: 30-90% 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

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.

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

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

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

Comments and Questions? Contact: susan.andrews@lin.usda.gov