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Forest and Rangeland Ecosystem Science Center. Jornada Experimental Range. Transitions in Rangeland Evaluations. David A. Pyke & Jeffrey E. Herrick. Rangeland Evaluations:. Age of Discovery - 1800’s to 1930 Rangeland Uses & Abuses Observations Age of Inventory - 1930’s to 1970’s
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Forest and Rangeland Ecosystem Science Center Jornada Experimental Range Transitions in Rangeland Evaluations David A. Pyke & Jeffrey E. Herrick
Rangeland Evaluations: • Age of Discovery - 1800’s to 1930 • Rangeland Uses & Abuses • Observations • Age of Inventory - 1930’s to 1970’s • Described Vegetation, Production, Soils • Taylor Grazing Act - Adjustments of AUM’s • Age of Planning & Management - 1970’s to 1990’s • Condition & Trend • Broader Objectives • Age of Sustainability - 2000 to ????
Age of DiscoveryWhat is the West? How can we use it? Powell • Settlers expected consistent moisture • Powell warned of the harsh environment • Livestock successful use • Livestock overuse observed by federal officials Pinchot
Succession & Indicators • Clements & Sampson • Plant communities change with grazing • Grazing sensitive or preferred species are reduced • Grazing tolerant and non-preferred increase • Basis of Clements 1920 book on indicators
Grazing Indicators • Observations from - • Smith, Bentley, Griffiths, Sampson, Jardine, Wooton & Sarvis • Certain species within communities are indicators of grazing abuse.
Age of Inventory • Dust Bowl leads to Taylor Grazing Act • Required inventories of the amount of forage available for livestock • Stoddart introduces rangeland condition classes • Dyksterhuis relates Clementsian succession to condition classes • Rangeland Classification • Dyksterhuis • Proposes range site concept • Daubenmire • Habitat types
Monitoring Techniques Begin • BLM • Deming 2-phase • Combination qualitative and quantitative (plot)data • USFS • Parker 3-step • 100 points on transect with loop frequency/cover K. W. Parker
Monitoring Focus • Vegetation tends to dominate over soils • SCS still maintains soil-vegetation emphasis • Forage plants & undesirable plants are indicators of rangeland status • Upland communities are the focus • Lands around water sources tend to be sacrificed • Wildlife habitat needs are secondary to livestock needs
Heady 1975 Rangeland Mgmt. Stoddart, Smith & Box. 1975. Range Management
Congressional Directions • Forest & Rangeland Renewable Resources Planning Act of 1974 • USFS Habitat types were mapped • Federal Land Policy & Management Act of 1976 • BLM Soil Vegetation Inventory Method (SVIM) • Soil & Water Resources Conservation Act of 1977 • National Resources Inventory (NRI)
Inventory Condition & Trend • All agencies used some form of Dyksterhuis’ Condition Ratings • Monitored trend using various techniques • Biomass or cover • Theory behind cond. & trend was still Clementsian succession
Utilization becomes Important • Measure of the percent production consumed • Direct via biomass • Indirect via height:weight • Done on a species-basis • Difficult to determine utilization of pastures • Estimated by ocular estimate maps
Key Species • Utilization by species lead to key species being monitored. • Selected up to four species • Utilization consistent over season • Sufficient abundance and palatability for livestock • Should make up the majority of forage
Weakness of Key Species Concept • Less abundant, highly palatable species are sacrificed • Rangelands recovering from excessive livestock grazing in the early 1900’s : • Former dominant, but palatable species would be rare • Some dominant or co-dominant palatable species might have been sacrificed. • Possible example - Basin Wildrye
Introduction of New Ecological Concepts • Biological Diversity • Species richness, evenness • Diversity among communities • Non-equilibrium ecosystem dynamics • State & transition successional models • Thresholds of community change • Riparian and wetland communities as integral parts of rangelands • Ecosystem processes • Nutrient & water cycles, energy flow
Age of Sustainability??? • West 2003 - Risk Assessment, Sustainability, Desertification • Evaluations not focused on single use • Evaluations strive to incorporate multiple scales • Upland & Riparian ecosystems often given equal weight in evaluations
Upland Evaluations & Community Dynamics Reference State Shrub - Annual Grass State Threshold Annual Grass State
Evaluations of Ecosystem Processes • Interpreting Indicators of Rangeland Health • 3 Attributes (Site Stability, Hydrologic Function, Biotic Integrity; 17 indicators with some overlapping • Qualitative with Quantitative methods proposed & being tested • Landscape & Ecosystem Analysis (Tongway et al) • 3 indices (Stability, Infiltration, Nutrient cycling); Multiple indicators) • Quantitative methods published Soil/Site Stability Biotic Integrity Hydrologic Function
Riparian, Wetland & Aquatic Bear Cr. 1977 Season long use • Water quality measures • Stream Geomorphic Classifications • Stream Cross sections • Veg. Classification based on soil and water table depth. • Greenline techniques • Proper functioning condition • Wetland & stream invertebrates Bear Cr. 1987 Winter use
National/Regional Assessments Sustainable Rangelands Roundtable • Sustainable Rangeland Roundtable • 5 criteria; measured indicators/criteria • Ecological, Social & Economic • Heinz Center • 10 national & 14 grassland & shrubland indicators • Many indicators not populated • NRI • Rangeland NRI begun in 2003 • Non-federal lands National Resources Inventory
Remote Sensing & GIS • Combine soil, climate and current vegetation • Large areas • Allows for use of predictive models • Invasion risk • Erosion potential • Useful for wildlife habitat assessments • Multiple scales Wisdom et al. 2003
Landscapes:Patterns, Processes, Resistance & Resilience • Linkages across multiple scales • Fragmentation monitoring • Prediction early ID of threats and drivers • Interactions among multiple threats
Future Evaluations: Carbon? • Carbon Credits on Rangelands • What could be included • How to measure? • International politics may dictate the need