Natural Resources
Conservation Service
Semidesert Alkali Loam (Black Greasewood) South
Scenario model
Current ecosystem state
Select a state
Management practices/drivers
Select a transition or restoration pathway
- Transition T1a More details
- Transition T2a More details
- Transition T3a More details
- Transition T3b More details
- Transition T4a More details
-
No transition or restoration pathway between the selected states has been described
Target ecosystem state
Select a state
Description
The Reference State is a representative of the natural range of variability under reference conditions. The Reference State has three general community phases; a shrub grass dominant phase, a perennial grass dominant phase and a shrub dominant phase. State dynamics are maintained by interactions between climatic patterns and disturbance regimes. Negative feedbacks enhance ecosystem resilience and contribute to the stability of the state. These include the presence of all structural and functional groups, low fine fuel loads, and retention of organic matter and nutrients. Plant community phase changes are primarily driven by fire, periodic drought and/or insect or disease attack.
Submodel
Description
Plant communities in the Current Potential State can include both native and non-native species. This state is irreversibly changed from the Reference State because the non-native species will now remain a permanent part of the community.
Submodel
Description
Native shrubs dominate with an understory of invasive annuals. Native herbaceous plants have been removed either from poor management and/or change in fire return interval.
Submodel
Description
Invasive non-native annuals dominate. This can occur from a decrease in the fire return interval, with fire occurring more frequently than typical for the site. This increase in the occurrence of fire can make it difficult even for shrubs that sprout like greasewood and rabbitbrush to survive. Frequent fires favor the establishment and dominance of annual species, like cheatgrass. Once annual species are dominant, this increases the likelihood of the site to be burned on a regular basis because of the increase in fine fuels.
Submodel
Description
The Seeded Range State is seeded to species that may be composed of introduced and native species. Shrubs may or may not be present in this state, but are typically present from natural regeneration. Invasive annual species are also typically present.
Submodel
Mechanism
Introduction and establishment of non-native species. This decreases resistance and resilience to disturbance.
Mechanism
Decrease in shrub removal disturbance, like fire. This can increase shrub dominance and decrease herbaceous cover. This is often accompanied by an increase in non-native plant species.
Mechanism
Disturbance that removes shrubs, such as fire. Fire in this state when there is a dominance of annual non-native grass, like cheatgrass, will create a community after the fire that is often dominated by annual non-native species.
Mechanism
Human intervention with the introduction of native or non-native bunchgrasses and forbs.
Model keys
Briefcase
Add { ecological sites } and { Major Land Resource Areas } to your briefcase by clicking on the briefcase
(
) 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.
Ecological sites
Major Land Resource Areas
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.
Accessibility statement