The Reference State represents the natural range of variability under pristine conditions and is dominated by drought tolerant shrubs. Primary natural disturbance mechanisms affecting this ecological site are long-term drought and insect attack. Historically, wildfire was infrequent and patchy due to low fuel loading, resulting in long-lived stable plant communities. Timing of disturbances combined with weather events determines plant community dynamics.
The Invaded State is characterized by the presence of non-natives in the understory. A biotic threshold has been crossed by the introduction on non-native annuals that cannot be removed from the system. Ecological function has not changed, however the resiliency of the state has been reduced by the presence of non-native species that have the potential to significantly from their natural range of variability.
Introduced annuals such as red brome, schismus and redstem stork's bill have invaded the reference plant community and have become a dominant component of the herbaceous cover. This invasion of non-natives is attributed to a combination of factors including: 1) surface disturbances, 2) changes in the kinds of animals and their grazing patterns, 3) drought, and 4) changes in fire history. These non-natives annuals are highly flammable and promote wildfires where fires historically have been infrequent.
The Eroded State is characterized by decreased soil stabilization. Loss of vegetation and soil crust has negatively impacted ecological processes, leading to increased runoff and decreased infiltration and nutrient cycling.
Introduction of non-native invasive species from anthropogenic disturbances, including OHV use, dry land farming, grazing, linear corridors, mining, military training operations, and settlements.
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The Ecosystem Dynamics Interpretive Tool is an information system framework developed by the USDA-ARS Jornada Experimental Range, USDA Natural Resources Conservation Service, and New Mexico State University.
) icon wherever it occurs. Drag and drop items to reorder. Cookies are used to store briefcase items between browsing sessions. Because of this, the number of items that can be added to your briefcase is limited, and briefcase items added on one device and browser cannot be accessed from another device or browser. Users who do not wish to place cookies on their devices should not use the briefcase tool. Briefcase cookies serve no other purpose than described here and are deleted whenever browsing history is cleared.
