Droughty Fan 9-12 PZ
Scenario model
Current ecosystem state
Select a state
Management practices/drivers
Select a transition or restoration pathway
-
Transition T1A
Introduction of non-native plants
More details -
Transition T2A
Chronic improperly managed grazing or prolonged time without fire sufficient enough for the perennial grass seedbank to diminish.
More details -
Transition T2B
Catastrophic fire, soil disturbing treatments or prolonged improperly managed grazing in the presence of non-native annual species.
More details -
Transition T2C
Time and lack of disturbance allows for maturation of the tree community, possibly in combination with improperly managed grazing
More details -
Restoration pathway R3A
Shrub management and seeding of native species coupled with minimal soil disturbance, potentially requiring the use of herbicide.
More details -
Transition T3A
Catastrophic fire, failed rehabilitation treatment or prolonged improperly managed grazing in the presence of annual nonnative grasses.
More details -
Transition T3B
Time and lack of disturbance allows for maturation of the tree community. May be combined with inappropriate grazing management.
More details -
Restoration pathway R3B
Shrub management and seeding species coupled with minimal soil disturbance, potentially requiring the use of herbicide.
More details -
Restoration pathway R4A
Reduction of annual grasses through herbicide use and seeding of desired species.
More details -
Restoration pathway R5B
Tree removal with minimal soil disturbance
More details -
Transition T5A
Catastrophic fire, multiple fires or failed rehabilitation attempt.
More details -
Restoration pathway R5A
Tree removal and seeding of desired species; potentially including herbicide use.
More details -
Transition T6A
Prolonged improperly managed grazing or lack of fire for an extended interval in the presence of a shrub component.
More details -
Transition T6B
Catastrophic fire or prolonged inappropriate grazing management in the presence of non-native annual grasses.
More details -
Transition T6C
Extended time without fire with western juniper present.
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 representative of the natural range of variability for the site under pristine conditions. The reference state is a bunchgrass shrubland. 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 are maintained by elements of ecosystem structure and function such as the presence of all structural and functional plant groups, the retention of organic matter and the maintenance of plant community cover. Plant community phase changes are primarily driven by infrequent fire and/or periodic drought.
Submodel
Description
This state is similar to the Reference State. Ecological function has not changed fundamentally, however the resiliency of the site has been reduced by the presence of invasive weeds. Additionally, livestock herbivory may be present as a disturbance process and changes in climate may be altering ecological dynamics. Non-native plant species may increase in abundance but will not become dominant or control ecological processes within this state. These species can be highly flammable and can promote fire where historically fire had been infrequent. Negative feedbacks enhance ecosystem resilience and contribute to the stability of the state. These are maintained by elements of ecosystem structure and function such as the presence of all structural and functional groups, and retention of organic matter and nutrients. Positive feedbacks driven by plant community invasion decrease ecosystem resilience and stability of the state. These include exotic plant species' high seed output, persistent seed bank, rapid growth rate, ability to cross pollinate, and adaptations for seed dispersal. Plant community phase changes are primarily driven by infrequent fire, periodic drought and ungulate herbivory.
Submodel
Description
Within this state, site resources are primarily controlled by shrub species. Native perennial grass composition has been reduced considerably. Sprouting and non-sprouting shrubs are dominant and western juniper is often present. Exotic herbaceous species may occur.
Submodel
Description
Within this state, site resources are primarily controlled by exotic annual and perennial herbaceous species. Native perennial grass composition has been greatly diminished. Shrub species and western juniper may also be present.
Submodel
Description
Within this state, site resources are primarily controlled by western juniper dominance. Native perennial grass and shrub composition have been greatly diminished and as canopy closure progresses will be further reduced. Exotic annual plant species are likely.
Submodel
Description
Within this state, site resources are primarily controlled by introduced range grasses such as crested wheatgrass (Agropyron cristatum). Multiple community phases may occur within this state and will include different compositions of native and invasive shrub and grass species and western juniper. Similar to ecological dynamics within other states of this site, shrub species and western juniper will increase with greater time since fire and herbivory pressure. While introduced range grasses may provide some analogous ecological functions to native perennial grasses, they may outcompete native grasses in the long-term.
Mechanism
Chronic improperly managed grazing or prolonged time without fire sufficient enough for the perennial grass seedbank to diminish.
Mechanism
Catastrophic fire, soil disturbing treatments or prolonged improperly managed grazing in the presence of non-native annual species.
Mechanism
Time and lack of disturbance allows for maturation of the tree community, possibly in combination with improperly managed grazing
Mechanism
Shrub management and seeding of native species coupled with minimal soil disturbance, potentially requiring the use of herbicide.
Context dependence
Risk of failure may be high due to droughty nature of the site and low resilience.
Mechanism
Catastrophic fire, failed rehabilitation treatment or prolonged improperly managed grazing in the presence of annual nonnative grasses.
Mechanism
Time and lack of disturbance allows for maturation of the tree community. May be combined with inappropriate grazing management.
Mechanism
Shrub management and seeding species coupled with minimal soil disturbance, potentially requiring the use of herbicide.
Context dependence
Risk of failure may be high due to droughty nature of the site and low resilience.
Mechanism
Reduction of annual grasses through herbicide use and seeding of desired species.
Context dependence
Risk of failure may be high due to droughty nature of the site and low resilience.
Mechanism
Catastrophic fire, multiple fires or failed rehabilitation attempt.
Mechanism
Tree removal and seeding of desired species; potentially including herbicide use.
Context dependence
Risk of failure may be high due to droughty nature of the site, low resilience and potential for soil disruption from tree removal.
Mechanism
Prolonged improperly managed grazing or lack of fire for an extended interval in the presence of a shrub component.
Mechanism
Catastrophic fire or prolonged inappropriate grazing management in the presence of non-native annual grasses.
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.