Linked Ecological and Economic State and Transition Model for Adaptive Management of Rangeland Ecosystems

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1 Linked Ecological and Economic State and Transition Model for Adaptive Management of Rangeland Ecosystems John Ritten 1, Maria E. Fernandez- Gimenez 2, Willow Hibbs 2, Emily Kachergis 3, Windy Kelley 2, James Pritchett 4, Roy Roath 2, and Monique Rocca 2 1 Department of Agricultural and Applied Economics, University of Wyoming, Laramie, Wyoming 2 Department of Forest, Range, and Watershed Stewardship, Warner College of Natural Resources, Colorado State University, Fort Collins, Colorado 3 Graduate Program in Ecology, Colorado State University, Fort Collins, Colorado 4 Department of Agricultural and Resource Economics, College of Agricultural Sciences, Colorado State University, Fort Collins, Colorado

2 Overview Multidisciplinary team Link an economic and ecological model State and Transition framework Examine trade-offs between short-term stocking rates and long-term profitability Include ecosystem service in model framework Examine impacts if decisions are based on more than livestock production

3 State and Transition Models Diagrams, text descriptions, and associated data that describe possible changes in plant communities and soils within particular ecological sites Conceptual models of vegetation change community transition 1 State A transition 2 State B (adapted from Bestelmeyer 2003, 2009) State C

4 General Model Framework Management Unit Economic State Herd Size Ecological State Site Composition: -Production -Ecosystem Services Decisions Stocking Rate Hay Weed Control Weather + Fire Occurrence + Probabilities Ecological State A (e.g. Natural sagebrush steppe) Ecological State B (e.g. Weedy sagebrush steppe) Economic State Profit Herd Size Managers Values, Goals, Knowledge & Experience

5 Location of Study Elkhead Watershed: Northern Colorado Near Steamboat

6 STM Model Parameterization Mainly data-driven Field work to determine: Ecological states Production potential (livestock) Ecosystem service attributes Some basis on local knowledge Transition probabilities given nature and management decisions Also based on observed data when possible

7 Mountain Loam vs. Claypan Different potential vegetation and soils Mountain Big Sagebrush + Loam or Clay Loam Soil Alkali Sagebrush (Chicken Sage) + Clay Soil

8 Focal Ecological Sites in Elkhead Region Mountain Loam Aspen Claypan

9 Ecological Sites/States Claypan: Diverse and Alkali Sage/Bluegrass Alkali Sage/Western Wheatgrass Eroding Alkali Sage Native Grassland Mountain Loam: Dense Mountain Big Sagebrush Mountain Big Sage with Diverse Understory Mountain Big Sage/Western Wheatgrass Aspen: Grass/Shrub Tall Forb

10 Ecosystem Services Wildlife habitat: Mule Deer, Elk, Sage Grouse Soil resistance to erosion Plant community resistance to invasion Overall Plant biodiversity

11 Ecosystem services derived directly from ecological data Resistance to Erosion Qualitative Indicators of Rangeland Health Negatively related to erosion potential Plant Diversity Average plant species richness per plot within State Plant Production Measured at peak production Resistance to Invasive Plants Relative cover of invasive plants Negatively related to resistance

12 Habitat indices derived by modeling habitat attributes as the degree to which they meet habitat management recommendations

13 Basic Ranch Information Basic Ranch Description: Land Site Acres Claypan 2,392 Mountain Loam 1,057 Aspen 386 Riparian 200 Public Lease 400 Hayed Meadows 800

14 Economic Model Bellman Equation Maximum value is based on optimal decisions over an infinite horizon Model solves optimal decisions given any state combination

15 Economic Model Framework

16 Economic Model Framework

17 Economic Model Framework States: Decision Variables:

18 Economic Model Framework Random Nature Events:

19 Optimal Stocking Given Low or Moderating Existing Level Dense Mountain Big Sagebrush Mountain Big Sage with Diverse Understory Mountain Big Sage/Western Wheatgrass Diverse and Alkali Sage/Bluegrass Grass/Shrub Moderate High Moderate Tall Forb Moderate High Moderate Native Grassland Eroding Alkali Sage Grass/Shrub Moderate High Moderate Tall Forb Moderate High Moderate Grass/Shrub Low Moderate Low Tall Forb Low Moderate Low Alkali Sage/Western Wheatgrass Grass/Shrub Moderate High Moderate Tall Forb Moderate High Moderate

20 Optimal Stocking Given High Existing Level Dense Mountain Big Sagebrush Mountain Big Sage with Diverse Understory Mountain Big Sage/Western Wheatgrass Diverse and Alkali Sage/Bluegrass Grass/Shrub Moderate High Moderate Tall Forb Moderate High Moderate Native Grassland Eroding Alkali Sage Grass/Shrub Moderate High High Tall Forb Moderate High High Grass/Shrub Low Moderate Low Tall Forb Low Moderate Low Alkali Sage/Western Wheatgrass Grass/Shrub High High High Tall Forb High High High

21 Optimal Loam Spraying Given Low or Moderating Existing Level Dense Mountain Big Sagebrush Mountain Big Sage with Diverse Understory Mountain Big Sage/Western Wheatgrass Diverse and Alkali Sage/Bluegrass Grass/Shrub Spray Don't Spray Don't Spray Tall Forb Spray Don't Spray Don't Spray Native Grassland Eroding Alkali Sage Grass/Shrub Spray Don't Spray Don't Spray Tall Forb Spray Don't Spray Don't Spray Grass/Shrub Spray Don't Spray Don't Spray Tall Forb Spray Don't Spray Don't Spray Alkali Sage/Western Wheatgrass Grass/Shrub Spray Don't Spray Don't Spray Tall Forb Spray Don't Spray Don't Spray

22 Optimal Loam Spraying Given High Existing Level Dense Mountain Big Sagebrush Mountain Big Sage with Diverse Understory Mountain Big Sage/Western Wheatgrass Diverse and Alkali Sage/Bluegrass Grass/Shrub Spray Don't Spray Don't Spray Tall Forb Spray Don't Spray Don't Spray Native Grassland Eroding Alkali Sage Grass/Shrub Spray Don't Spray Spray Tall Forb Spray Don't Spray Spray Grass/Shrub Spray Don't Spray Don't Spray Tall Forb Spray Don't Spray Don't Spray Alkali Sage/Western Wheatgrass Grass/Shrub Spray Don't Spray Spray Tall Forb Spray Don't Spray Spray

23 Ecosystem Services in Conflict Diversity Deer critical value 0.4 critical value 125 Dense Mountain Big Sagebrush Mountain Big Sage with Diverse Understory Mountain Big Sage/Western Wheatgrass Dense Mountain Big Sagebrush Mountain Big Sage with Diverse Understory Mountain Big Sage/Western Wheatgrass Diverse and Alkali Sage/Bluegrass Grass/Shrub Diverse and Alkali Sage/Bluegrass Tall Forb Native Grassland Grass/Shrub Native Grassland Tall Forb Eroding Alkali Sage Grass/Shrub Eroding Alkali Sage Tall Forb Alkali Sage/Western Wheatgrass Grass/Shrub Alkali Sage/Western Wheatgrass Tall Forb Elk Erosion critical value 0.7 critical value 7 (10) Diverse and Alkali Sage/Bluegrass Grass/Shrub Diverse and Alkali Sage/Bluegrass Tall Forb Native Grassland Grass/Shrub Native Grassland Tall Forb Eroding Alkali Sage Grass/Shrub Eroding Alkali Sage Tall Forb Alkali Sage/Western Wheatgrass Grass/Shrub Alkali Sage/Western Wheatgrass Tall Forb Grouse Invasion critical value 0.5 critical value 1 Diverse and Alkali Sage/Bluegrass Grass/Shrub Diverse and Alkali Sage/Bluegrass Tall Forb Native Grassland Grass/Shrub Native Grassland Tall Forb Eroding Alkali Sage Grass/Shrub Eroding Alkali Sage Tall Forb Alkali Sage/Western Wheatgrass Grass/Shrub Alkali Sage/Western Wheatgrass Tall Forb

24 Impacts on Decisions Given Constraints on Ecosystem service Levels Changes in optimal decisions based on ecosystems service restrictions: Deer Elk Grouse Diversity Erosion Invasion SR Higher 18.06% 2.78% 5.56% 20.83% 0.00% 0.00% SR Lower 0.00% 1.39% 0.00% 0.00% 33.33% 2.78% Spray Loam 4.17% 2.78% 5.56% 0.00% 8.33% 5.56% Don't Spray 0.00% 0.00% 0.00% 34.72% 11.11% 0.00%

25 Results Both current ecological states (and resulting transition probabilities associated with management decisions) and economic conditions impact optimal behavior Management decisions are altered when accounting for ecological state impacts on ecosystem values Ecosystem Service are often in direct competition with each other Livestock Production nor any ecosystem service utilizes spraying of Claypan sites Livestock Production only utilizes spraying of Mountain Loam sites if costs are shared through program such as EQIP

26 Thanks! John Ritten University of Wyoming Dept. of Ag and Applied Economics