Closed Depression
Scenario model
Current ecosystem state
Select a state
Management practices/drivers
Select a transition or restoration pathway
- Transition T1A More details
- Restoration pathway T2A More details
-
No transition or restoration pathway between the selected states has been described
Target ecosystem state
Select a state
Description
The Reference State represents the natural range of variability that dominated the dynamics of this ecological site (ES). This state is co-dominated by cool-season grasses and grasslikes. Prior to Europeansettlement of North America, the primary disturbance mechanisms for this site in the Reference condition included periods of below and above average precipitation, periodic fire, and herbivory by insects and large ungulates. Timing of fires and herbivory coupled with weather events dictated the dynamics that occurred within the natural range of variability. Wheatgrass species can decline and a corresponding increase in foxtail barley (Hordeum jubatum), short, warm-season grasses and forbs will occur. Under extended periods of disturbance, the main change is a reduction in vigor and production and an increase in bare ground and forb composition.
Interpretations are based primarily on the 1.1 Reference Plant Community Phase. This plant community evolved with grazing by large herbivores and occasional fire, as well as periodic flooding and drying, and can be maintained with prescribed grazing, prescribed burning, or areas receiving occasional short periods of rest or deferment. This plant community phase has two sub-phases, just referred to as plant communities here. These sub-phases are mainly driven by precipitation and flooding and drying sequences.
Submodel
Description
The Native/Invaded State represents the range of variability that exists with reduced vigor and production of the dominant species as a result of grazing-induced disturbance and the introduction of non-native species. This state is dominated by cool-season grasses. It can be found on areas that are impacted by extended periods of heavy, continuous grazing. Grazing tolerant species become dominant, and non-native species are present.
Submodel
Mechanism
Heavy, continuous grazing (stocking levels well above carrying capacity for extended portions of the growing season, and often at the same time of year each year, typically beginning early in the season) or invasion of non-native plant species will convert the 1.1 Common Spikerush-Pale Dock Plant Communtity Subphase within the Reference State (State 1) to the 2.2 Curly Dock-Foxtail Barley Plant Community Phase within the Native/Invaded State (State 2).
Mechanism
Long-term prescribed grazing (moderate stocking levels coupled with adequate recovery periods, or other grazing systems such as high-density, low-frequency intended to treat specific species dominance, or periodic light to moderate stocking levels possibly including periodic rest) may lead the Native/Invaded State (State 2) over a threshold to the Reference State (State 1).
Relevant conservation practices
Practice | External resources |
---|---|
Prescribed Grazing |
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.