Alkaline Plains
Scenario model
Current ecosystem state
Select a state
Management practices/drivers
Select a transition or restoration pathway
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Transition T1A
Heavy, season-long grazing.
More details
Prescribed fire. -
Transition T1B
Long-term, heavy, continuous grazing.
More details
Lack of fire. -
Transition T1C
Mechanical tillage.
More details -
Restoration pathway R2A
Prescribed grazing.
More details
Prescribed fire. -
Transition T2A
Long-term, heavy, continuous grazing.
More details
Lack of fire. -
Restoration pathway R3A
Long-term prescribed grazing.
More details
Prescribed fire. -
No transition or restoration pathway between the selected states has been described
Target ecosystem state
Select a state
Description
The Reference state is characterized by three community phases that exist within the natural range of variability for the site. These phases are maintained by a historic fire frequency estimated to be on 15 to 20 year intervals and grazing by large ungulates with adequate recovery periods. High production of perennial grasses and extensive soil cover allow for increased soil moisture retention, vegetative production, and overall soil quality.
Submodel
Description
The Shortgrass Dominated state contains one community phase. This is a very stable state, resistant to change due to the high tolerance of blue grama to grazing, the development of a shallow root system (also known as a root pan), and subsequent changes in hydrology and nutrient cycling. The loss of dominant and subdominant functional/structural groups such as cool-season grasses, nitrogen fixing legumes, and shrubs reduces the biodiversity and productivity of this site and negatively impacts the energy flow and nutrient cycling. Water infiltration is reduced significantly due to the massive shallow root system “root pan”, characteristic of blue grama. Soil loss may be obvious where flow paths are connected.
Submodel
Description
This state is characterized by a loss of the more palatable species and a notable increase in bare ground. It lacks stability, diversity, and productivity. Litter levels are extremely low. Due to the increased bare ground erosion is evident where flow paths are continuous. Rills may occur on steeper slopes. The nutrient cycle, water cycle, and overall energy flow are greatly impaired. Organic matter and carbon reserves are greatly reduced.
Submodel
Description
This state is defined by two separate vegetation communities that are highly variable. They are derived through two distinct management scenarios, and are not successionally related. Infiltration, runoff, and soil erosion vary depending on the vegetation present.
The designation of the tillage state denotes changes in plant community composition and soil structure. This change in plant species and soil structure affects the hydrologic function, biotic integrity, and soil site stability.
Submodel
Mechanism
Heavy, continuous grazing without adequate recovery opportunity between grazing events and lack of fire result in shifts between states. The movement from the Reference State to the Short-grass Dominated State indicates that an ecological threshold has been crossed. This transition involves a major loss of plant diversity resulting in the degradation of biotic integrity.
Mechanism
Long-term, heavy, continuous grazing without adequate recovery opportunity between grazing events and lack of fire move this plant community across an ecological threshold to the Increased Bare Ground State. Resilience and resistance to disturbance will be lost. Soil site stability, hydrologic function, and biotic integrity, will be drastically altered.
Mechanism
Tillage (plowed & abandoned) will cause all states to transition across an ecological threshold to the Tilled State. The resulting change in plant species and soil structure will adversely affect hydrologic function, biotic integrity, and soil site stability. This transition is considered to be non-restorable.
Mechanism
Long term prescribed grazing management and prescribed fire are the management actions required to recover to the Reference State. The species to target for management are those that were dominant or sub-dominant within the reference plant community according to documented functional/structural groups. This restoration may take greater than 40 years.
Relevant conservation practices
| Practice | External resources |
|---|---|
|
Prescribed Burning |
|
|
Prescribed Grazing |
Mechanism
Long-term, heavy, continuous grazing without adequate recovery opportunity between grazing events and lack of fire cause a move to the Increased Bare Ground State. This transition may take greater than 25 years to occur. Resilience and resistance to disturbance will be lost. Soil site stability, hydrologic function, and biotic integrity will be drastically altered.
Mechanism
Long-term prescribed grazing with adequate recovery opportunity between grazing events and prescribed fire are the management actions required to recover to the Reference State. The species to target for management are those that were dominant or sub-dominant within the reference plant community according to the documented functional/structural groups. This restoration may take greater than 80 years to accomplish.
Relevant conservation practices
| Practice | External resources |
|---|---|
|
Prescribed Burning |
|
|
Prescribed Grazing |
Model keys
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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.