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Ecological Site Descriptions
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Ecological Site Descriptions 

Ecological sites comprise a land classification system that describes ecological potential and ecosystem dynamics of land areas. They are used to stratify the landscape and organize ecological information for purposes of monitoring, assessment, and management. This section of our website provides some definitions for ecological site descriptions (ESDs) and provides tools and literature pertaining to their development. A comprehensive guidance document for ESD development for the United States is being produced via cooperation of responsible federal agencies and is an active area of research at the Jornada Experimental Range. There are many ways ESD concepts can be developed and applied outside of the United States. Explore the ESD links further for more information


What is an ecological site?

An ecological site is distinctive kind of land with specific soil and physical 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. Unlike vegetation classification, ecological site classification uses climate, soil, geomorphology, hydrology, and vegetation information to describe the ecological potential of land areas. A particular ecological site may feature several plant communities (described by vegetation classification) that occur over time and/or in response to management actions.

What is an ecological site description?

Ecological site descriptions (ESDs) are reports that describe the a) biophysical properties of ecological sites, b) vegetation and surface soil properties of reference conditions that represent either i) pre-European vegetation and historical range of variation (in the United States) or ii) proper functioning condition or potential natural vegetation, c) state-and-transition model graphics and text, and d) a description of ecosystem services provided by the ecological site and other interpretations.

How are ecological sites mapped for use?

In the United States, ecological sites are connected to spatial data via soil map units of the National Cooperative Soil Survey. Classification of land areas to ecological sites can be easily visualized via Web Soil Survey of the USDA Natural Resources Conservation Service or within a personal GIS via SSURGO digital soil data. Ecological sites are linked to one or more map unit components of one or more soil map units. A soil map unit may have several map unit components that cannot be mapped separately (because they are finely intermingled, for example), so soil map unit polygons may not correspond in a 1:1 fashion with ecological sites. For SSURGO spatial data, map unit components can be connected to ecological site descriptions in a database by linking the map unit component to the ecological site class name in cecoclas.txt table and then to the map unit in the mapunit.txt via the comp.txt table (see figure below).

How are ecological sites used?

ESDs and associated information are used primarily to stratify the landscape for monitoring and assessment, interpretation of resource hazards and opportunities, and to prioritize and select management actions. ESDs are developed and housed by the NRCS and its partners, and used by the U. S. Bureau of Land Management (BLM), the The Nature Conservancy, and many other entities. A recent memorandum of understanding between the NRCS, BLM, and U.S. Forest Service establishes ESD development as an interagency priority and will establish national standards and protocols for ESD development.

What is a state-and-transition model?

The patterns, causes, and indicators of transitions between communities within an ecological site are described by state-and-transition models. State-and-transition models synthesize literature and informal knowledge tied to particular ecological sites to distinguish changes in vegetation and soils that are easily reversible versus changes that are subject to thresholds beyond which reversal is costly or impossible. The models describe all possible states, community phases (i.e., easily-reversible variants of states), and transitions between communities and states. Transitions contain information about mechanisms, triggers, thresholds, and indicators of threshold development.


Ecological Site Description Access

Locating Ecological Site Descriptions

The national set of Ecological Site Descriptions (ESDs) is a work in progress, so do not be surprised to find that they do not exist or are not complete for your area. Further, a process for efficiently locating ESDs for a land area is still being refined. Our current recommendation is to start with the SoilWeb Online Soil Survey Browser from the California Soil Resource Lab. There are several useful tools here, including cell-phone based location-specific soil queries (that is, what soil and ecological site am I standing on?).

http://casoilresource.lawr.ucdavis.edu/drupal/node/902

From this page, click on either the Google Maps or Google Earth link. Zoom in to the area of interest sufficiently so that the detailed (SSURGO) soil map unit lines are visible on the maps or imagery (try an eye altitude of <15 km in Google Earth). Be sure to wait a minute or two to let the soil map load.  Click on the soil map unit code of interest, from which a major soil component list and soil profile diagrams will appear. Then click on the soil map unit component name (e.g., Ascalon) that best matches the location of interest when there are multiple components. This step may require you to know the slope, landscape position, or the soil profile characteristics. Then, under Land Classification, click on the entry to the right of Ecological Site Description (e.g., Loamy Plains). This will link you directly to the ESD report. Click on the Complete Report on the left column to see the entire ESD (note that sometimes the .html link is incomplete).

The Ecological Site Information System can be accessed directly here - http://esis.sc.egov.usda.gov/Welcome/pgReportLocation.aspx?type=ESD

You will need to know the MLRA code number to locate a set of ecological sites for a broad geographic region. That code number can be found here - http://www.cei.psu.edu/mlra/


Ecological Site Development Resources

Here we provide some initial resources for those interested in developing ecological site descriptions. Formal protocols are being developed, so we include these resources for the benefit of those who are involved in ongoing efforts.

Following Bestelmeyer et al., (2009) and Moseley et al., (2010), we provide dataforms that can be used in vegetation and soil inventory. The sampling units we have used are 20 x 20 m (400m2) plots with a soil pit at the center. The Low Intensity Traverse form can be used to gather large numbers of samples across a project area and develop initial ecological site concepts. The Medium Intensity Plant Inventory can be used to collect quantitative data on vegetation using either ocular estimation of cover and/or production, line point intercept (LPI), or both. In high cover, high diversity environments, LPI is often preferred, whereas ocular estimates are useful in low cover and patchy environments and to record species that are rare at a site. Procedures for High Intensity Inventory are discussed in the Soil Change Guide and are used to provide detailed characterizations of an ecological state, often the reference state and community phase of an ecological site. The Medium or High Intensity Soil Characterization form can be used to collect information about the soil profile alongside vegetation data. Finally, the Medium or High Intensity Pedoderm and Pattern Classes form is used to gather information about soil surface properties in conjunction with vegetation and soil profile measurements.

A link to the Rangeland/ESD development database aka Database for Inventory Monitoring and Assessment (DIMA) is provided because there are forms in the database that accommodate data produced using these dataforms. Information about monitoring and assessment methods useful for ESD development (including LPI) is provided in Monitoring and Assessment resources and instructions for the use of the Pedoderm and Pattern Classes is provided in the Field Guide. We also provide some links to additional resources pertaining to climate, soils, and vegetation classification that can be used in ESD development.

 

Data forms for ESD development

Rangeland/ESD development database aka Database for Inventory Monitoring and Assessment (DIMA) (MS Access)
WARNING: ESD data forms have been updated (6/1/2011). These updates have not yet been incorporated into the database.

Monitoring and Assessment resources (also contains dataforms)

A Field Guide to Pedoderm and Pattern Classes

PRISM climate data

National and International Vegetation Classification and data access

NRCS Soil Data Mart


Ecological Site Description Literature

Rangelands Special Issue, Volume 32, Issue 6 (December 2010)

  1. Bestelmeyer, B. T. and J. R. Brown. 2010. An Introduction to the Special Issue on Ecological Sites. Rangelands 32:3-4.
  2. Bestelmeyer, B. T., K. Moseley, P. L. Shaver, H. Sanchez, D. D. Briske, and M. E. Fernandez-Gimenez. 2010. Practical guidance for developing state-and-transition models. Rangelands 32:23-30.
  3. Brown, J. R. 2010. Ecological Sites: Their History, Status, and Future. Rangelands 32:5-8.
  4. Duniway, M. C., B. T. Bestelmeyer, and A. Tugel. 2010. Soil processes and properties that distinguish ecological sites and states. Rangelands 32:9-15.
  5. Gilgert, W. and S. Zack. 2010. Integrating Multiple Ecosystem Services Into Ecological Site Descriptions. Rangelands 32:49-54.
  6. Karl, J. W. and J. E. Herrick. 2010. Monitoring and Assessment Based on Ecological Sites. Rangelands 32:60-64.
  7. Knapp, C. N., M. E. Fernandez-Gimenez, and E. Kachergis. 2010. The Role of Local Knowledge in State-and-Transition Model Development. Rangelands 32:31-36.
  8. Moseley, K., P. L. Shaver, H. Sanchez, and B. T. Bestelmeyer. 2010. Ecological site development: A gentle introduction. Rangelands 32:16-22.
  9. Stringham, T. K. and J. P. Repp. 2010. Ecological Site Descriptions: Consideration for Riparian Systems. Rangelands 32:43-48.
  10. Talbot, C. J., S. B. Campbell, M. Hansen, and A. B. Price. 2010. Information Technologies and Ecological Site Descriptions. Rangelands 32:55-59.
  11. Townsend, L. 2010. Ecological Site Descriptions: Developmental Considerations for Woodlands and Forests. Rangelands 32:37-42.


  1. Aguilera, M.O., D.F. Steinaker, M.R. Demaría, A.O. Ávila. 1998. Estados y transiciones de los pastizales de Sorghastrum pellitum del área medanosa de San Luís, Argentina. Ecotropicos 11: 107-120.
  2. Bestelmeyer, B.T., J.R. Brown, K.M. Havstad, G. Chavez, and R. Alexander, and J.E. Herrick. 2003. Development and use of state-and-transition models for rangelands. Journal of Range Management 56: 114-126.
  3. Bestelmeyer, B.T., J.E. Herrick, J.R. Brown, D.A. Trujillo, K.M. Havstad. 2004. Land management in the American Southwest: a state-and-transition approach to ecosystem complexity. Environmental Management 34: 38-51.
  4. Bestelmeyer, B. T., D. A. Trujillo, A. J. Tugel, and K. M. Havstad. 2006. A multi-scale classification of vegetation dynamics in arid lands: what is the right scale for models, monitoring, and restoration? Journal of Arid Environments 65: 296-318.
  5. Bestelmeyer, B. T., A. J. Tugel, G. L. Peacock, Jr., D. G. Robinett, P. L. Shaver, J. R. Brown, J. E. Herrick, H. Sanchez, and K. M. Havstad. 2009. State-and-transition models for heterogeneous landscapes: A strategy for development and application. Rangeland Ecology and Management 62:1-15.
  6. Briske, D. D., B.T. Bestelmeyer, T.K. Stringham, and P.L. Shaver. 2008. Recommendations for development of resilience-based state-and-transition models. Rangeland Ecology and Management 61:359-367.
  7. Briske, D. D., S. D. Fuhlendorf, and F. E. Smeins. 2005. State-and-transition models, thresholds, and rangeland health: a synthesis of ecological concepts and perspectives. Rangeland Ecology and Management 58:1-10.
  8. Briske, D. D., S. D. Fuhlendorf and F. E. Smeins. 2006. A unified framework for assessment and application of ecological thresholds. Rangeland Ecology and Management 59:225-236.
  9. Brown, J. R. and B. T. Bestelmeyer. 2008. Resolving critical issues for the development of ecological site descriptions: Summary of a symposium. Rangelands 30: 16-18.
  10. Brown, J. R., T. Svejcar, M. Brunson, J. Dobrowolski, E. Fredrickson, U. Krueter, K. Launchbaugh, J. Southworth and T. Thurow. 2002. Range Sites: Are they the appropriate spatial unit for measuring and managing rangelands? Rangelands 24: 7-12.
  11. Burkett, L. M., B. T. Bestelmeyer A. J. Tugel. 2011. A Field Guide to Pedoderm and Pattern Classes, Version 1.1.  59 pp.
  12. Creque, J. A., S. D. Bassett, and N. E. West. 1999. Viewpoint: Delineating ecological sites. Journal of Range Management 52: 546-549.
  13. Dyksterhuis, E.J. 1949. Condition and management of rangeland based on quantitative ecology. Journal of Range Management 2: 104-115.
  14. Dyksterhuis, E.J. Ecological Principles in Range Evaluation. 1958, Botanical Review, 24:253-272.
  15. Herrick, J.E., B.T. Bestelmeyer, S.R. Archer, A.J. Tugel, and J.R. Brown. 2006. An integrated framework for science-based arid land management. Journal of Arid Environments 65: 319-335.
  16. Karl, J., Herrick J.E. 2010. Monitoring and assessment based on ecological sites. Rangelands. 32(6):60-64.
  17. Miller, M.E. 2005. The structure and functioning of dryland ecosystems: Conceptual models to inform long-term ecological monitoring. U. S. Geological Survey Scientific Investigations Report 2005-5197. Reston, VA. 74 pp.
  18. Peterson, F. F. 1981. Landforms of the Basin and Range Province, Defined for Soil Survey. Technical Bulletin 28, Nevada Agricultural Experiment Station, University of Nevada, Reno.
  19. Schoeneberger, P.J., Wysocki, D.A., Benham, E.C., and Broderson, W.D. (editors), 2002. Field book for describing and sampling soils, Version 2.0. Natural Resources Conservation Service, National Soil Survey Center, Lincoln, NE.
  20. Shiflet, T.N. 1975. Range Sites and Soils in the United States. In: D.N. Hyder (ed). Proceedings of the Third Workshop of the US/Australia Rangelands Panel. Society for Range Management, Denver, CO.
  21. Skaggs, R., Z. Edwards, B.T. Bestelmeyer, J.B. Wright, J. Williamson, P. Smith. 2011. Vegetation Maps at the Passage of the Taylor Grazing Act (1934): A Baseline to Evaluate Rangeland Change After a Regime Shift. Rangelands 33(1):13-19.
  22. Stringham, T.K., W.C. Krueger, and P.L. Shaver. 2003. State and transition modeling: an ecological process approach. Journal of Range Management 56: 106-113.
  23. Tugel, A., J. E. Herrick, J. R. Brown, M. J. Mausbach, W. Puckett, K. Hipple. 2005. Soil change, soil survey, and natural resources decision making: a blueprint for action. Soil Science Society of America Journal 69: 738–747.
  24. Westoby, M, B. Walker, and I. Noy-Meir. 1989. Opportunistic management for rangelands not at equilibrium. Journal of Range Management 42: 266-274.


Ecological Site Description Workshops and Presentations

(See http://jornada.nmsu.edu/esd/workshops for a complete list of workshops and presentations)

Ecological Site Description Development Workshop

November 15-18, 2005

Jornada Experimental Range, New Mexico State University, Las Cruces, NM
State and Transition Monitoring Workshop

August 28-30, 2006

Corvallis, Oregon
Integrating Soil Properties and Ecological Site Descriptions

September 26-27, 2006

Las Cruces, NM

This was a meeting of the Interagency Ecological Site Manual Team and included participants from Bureau of Land Management, Forest Service, ARS-Jornada Experimental Range, National Park Service, and Natural Resources Conservation Service. This meeting was hosted by Agricultural Research Service-Jornada Experimental Range, Las Cruces, New Mexico.

Riparian Ecological Site Description Workshop

August 14-16, 2007

Albuquerque, NM

Selected Key Terms, Stream Geomorphology- by W. Barry Southerland, Fluvial Geomorphologist

Part 654 - Stream Restoration Design- USDA, Natural Resources Conservation Service

Understanding and Improving Applications for Wildlife Habitat Management in Sagebrush Ecosystems

October 23-25, 2007

Park City, Utah

Following the workshop, there were many requests for opportunities to view the high quality presentations provided at the workshop. As a result, speaker presentations are now availbable at: http://rangelands.org/esd_presentations.shtml

We thank the speakers for their efforts at the workshop and their willingness to share their informative presentations.

Workshop organizers have also produced a "Synthesis of the Comments From the Breakout Sessions". This document can be viewed at: http://www.rangelands.org/pdf/esd_summary_recommendation.pdf

State-and-Transition Models: Triggers, Feedbacks and Thresholds

January 28, 2008

Louisville, Kentucky

The 2008 Joint Meeting of the Society for Range Management and the American Forage and Grassland Council

Climate Change and Potential Natural Vegetation

63rd Annual Meeting of the Society for Range Management, Denver, CO

February 2010

Land managers, federal agencies, and international aid organizations often recognize management targets and degradation based on ecological potential, historical range of variation, or potential natural vegetation. This relationship has been codified in U.S. rangeland management via ecological site descriptions (ESDs). Climate change may dramatically alter potential natural vegetation in many rangelands. Unless ESDs can be developed to anticipate and accommodate climate change effects, they could rapidly become obsolete. On the other hand, ESDs could serve as valuable tools for understanding how climate change effects are mediated by soil-geomorphic properties and existing vegetation condition.

New Mexico Ecological Site Description Core Group

General ESD/S&T presentation

General state-and-transition model presentation

ESD development presentation


   
 
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