Location: Range Management Research2008 Annual Report
1a. Objectives (from AD-416)
The goal of the research unit based at the Jornada Experimental Range (JER) is to develop ecologically based technologies for monitoring, remediation, and grazing management in desert environments. In order to achieve this goal, our overall research objective is to determine how biological (plant, animal, microbial), soil, and geomorphological processes interact across multiple spatial and temporal scales to affect soil development, soil stability, nutrient and water retention and acquisition, plant establishment and survival, and animal foraging behavior. Our ecologically based management technologies will be built from a knowledge of these processes. We will accomplish this objective by integrating short- and long-term experiments with a suite of tools (simulation modeling, geographic information systems [GIS], and remote sensing) to extrapolate information across spatial scales from individual plants to landscapes. Such an approach will enable us to accomplish four specific objectives and associated products: 1. Develop an integrated assessment and monitoring approach for vegetation structure and composition, soil stability, watershed function, and biotic integrity of spatially and temporally heterogeneous rangelands at landscape, watershed, and regional scales. 2. Identify key plant and soil processes, and environmental factors, such as landscape position, land use history, and climate, that influence the potential for remediation success. 3. Develop adaptive strategies for livestock management across multiple scales based on animal foraging behavior. 4. Predict responses of ecosystem dynamics and livestock distribution across time and space to changes in climate and other management-dependent and -independent drivers, and develop an integrated management, monitoring, and knowledge toolbox that can be easily applied by individuals with a range of management experience, from minimal to extensive.
1b. Approach (from AD-416)
We will build upon information collected since 1912, complemented with ongoing and new research, to address our objectives. We will integrate short- and long-term data sets with simulation modeling, geographic information systems, and remote sensing tools. Our approach will combine short-term experiments to test specific hypotheses with synthetic experiments requiring a more complex integration of ecosystem components and drivers. Objective 1 is shared among numerous collaborators where we are evaluating ground-based and remotely sensed indicators of ecosystem properties for use at multiple-spatial scales for effectiveness in monitoring resource conditions. Objective 2 is addressed by studies to identify areas within landscapes where stimulation of key processes will generate recovery of desired functions or control of undesired species. Objective 3 is addressed by (a) developing techniques that control animal movements on rangelands, (b) rapidly identifying botanical composition of livestock diets, and (c) identifying cattle breeds adapted to nutritional forage and environmental conditions of deserts. Objective 4 is shared by the National Science Foundation Long-Term Ecological Research project at the Jornada. Experimentation involves long-term studies of the effects of disturbances on ecosystem properties. For example, we have well-established studies that quantify pattern and control of primary productivity.
3. Progress Report
Progress was made on all four objectives and their subobjectives, all of which fall under National Program 215, Component I, Rangeland Management Systems to Enhance the Environment and Economic Viability. Progress on this project focuses on Problem A, the need for economically viable rangeland management practices, germplasm, technologies, and strategies to conserve and enhance rangeland ecosystems, and Problem B, the need for improved rangeland production systems for rangelands that provide and use forages in ways that are economically viable and enhance the environment. Under Objective A.1, we made significant progress in developing management and monitoring strategies that conserve natural resources. These strategies were developed for arid and semi-arid rangelands in North America and Asia. State and transition models, ground-based indicators, and remote sensing technologies were developed and tested as a suite of monitoring technologies for a broad range of spatial and temporal scales. These technologies also address Objective B.1, to develop monitoring tools and management strategies for managers, because they are being adopted by other federal agencies, such as the BLM, in monitoring rangeland status and change. Under Objective A.3, we made significant progress in identifying factors that can be used to predict and minimize rangeland degradation. We made progress toward demonstrating the role of endophytes in stomatal function in plants that can be used to improve revegetation success, with special emphasis on restoring degraded arid grasslands in the southwestern US. Progress was also made in determining the role of landscape context and connections among spatial units in limiting remediation success. Progress was made in identifying new methods to modify the spatial distribution of water, with influences on the spatial pattern in plant establishment. Under Objective B.4, we made significant progress in assessing animal productivity under alternative management strategies. Progress was made toward identifying the mixtures of terpenes that limit palatability of shrubs to livestock. Progress was also made in determining differences in traits and effects on rangeland ecosystems between aridland-adapted cattle (Criollo) and European breeds. Progress was also made in testing inexpensive sensors to control cattle movement using directional virtual fencing technology.
1. Procedure to test and refine state-and-transition models (STMs): Long-term data are often unavailable to test STMs. Inventory data examined the frequency distribution of states across soil/climate gradients as indicator of resilience of ecological sites. Datasheets, procedures, and website were developed, and database format was integrated into a monitoring and assessment tool; approach was presented to scientists in US, China, Mongolia, and Australia. Approach provides data-driven development of STMs to interpret monitoring and assessment data for the NRCS Conservation Effects Assessment Program (CEAP) for grazing lands. Interpretations enable decision-making to target restoration activities and to modify management to increase rangeland sustainability. (NP215, Component 1) (Project Objective 1a)
2. Development and calibration of ground-based indicators of ecosystem processes: Cost-effective vegetation and soil measures are needed that reflect status of underlying processes. Analyses for sites in Nevada, Utah, and New Mexico showed the relationship between indicators and ecosystem processes varies with ecological site. Information will be used by the Bureau of Land Management, National Park Service, and other agencies to evaluate effects of management practices on the status of >100 million acres of US western rangelands. (NP215, Component 1) (Project Objective 1b)
3. Improved remote sensing technologies for monitoring patterns: Measurements of rangeland health and vegetation structure from ground surveys are limited by monetary and personnel resources that constrain spatial coverage. Remote sensing sensors were evaluated for their ability to measure vegetation and soil metrics at high resolution over large areas. An unmanned aerial vehicle (UAV) produced digital information on bare and vegetated patches at a resolution of 5 cm. Information can be incorporated into rangeland health protocols and used to assess connectivity of vegetation and soils across landscape units. NRCS and BLM sites were used as test cases for evaluating methods. (NP215, Component 1) (Project Objective 1c)
4. Reduction of endophyte colonization of stomata in micropropagated shrubs: Endophytes are associated with desert plants, yet demonstrating their role in stomatal function and water loss has been hampered by an inability to cultivate plants independent from endophytes. Utility of fungicides for removing endophytes from host plants was determined. Treatment with 14 mg/mL iprodione fungicide successfully removed trypan blue stain, indicative of fungal chitin, from stomata of shrubs. Treated stomata opened completely, suggesting a loss of the shrubs' ability to reduce water loss. Results documented endophyte involvement in process crucial for regulating water loss, and will be used in future remediation studies. (NP 215, Component 1) (Project Objective 2a)
5. Inventory/monitoring to test effects of landscape context: Variation in soils and management can obscure effects of landscape context on grassland dynamics. Designs involving hierarchical stratification and high replication were used to factor out effects of variation in soils and current/past land use. Approvimately 200 plots were located that differed in landscape position and were characterized for erosion potential; change in vegetation will be monitored for 5 years. Procedures will enable designs to better ascribe specific causes to changes in vegetation, thereby increasing the ability of data to support management actions in private and public rangelands. (NP 215, Component 1) (Project Objective 2b)
6. Importance of landscape connectivity for remediation success: Role of landscape context and connections among spatial units in limiting remediation efforts needs to be better understood to increase the success rate of these efforts. Analyses from long-term manipulations indicate that runoff-barriers (low dikes) can modify plant establishment success. Land managers can use this result to identify the landscape locations where modification of resource redistribution is more likely to establish desirable plants. (NP215, Component 1) (Project Objective 2c)
7. Role of volatile terpenes in livestock herbivory: Shrub invasion reduces forage availability for livestock, partially as a result of volatile compounds that make shrubs such as tarbush unpalatable. Tarbush leaves were examined for negative effects on intake by small ruminants. Mixtures of seven monoterpenes and four sesquiterpenes were tested for cumulative or synergistic effects on intake. Identifying sesquiterpene mixtures that reduce intake can be used to overcome low intake of shrubs by livestock. (NP 215, Component 1) (Project Objective 3a)
8. Electronics platform for free-ranging cattle: Cattle movement has traditionally been controlled through costly, high maintenance fencing. Inexpensive alternatives using sensors carried by animals are being investigated. An inexpensive (approx. $10 apiece), lightweight (approx. 1120 g), animal-safe, simple to construct platform was developed and field tested on cows for carrying directional virtual fencing (DVF™) electronics hardware. Equipment provides extended (>30 days) periods for controlling or gathering free-ranging cattle, and should serve as a prototype for commercial cattle virtual fencing systems. (NP 215, Component 1) (Project Objective 3b)
9. Effects of arid land adapted Criollo cattle on western landscapes: Increasing costs for fuel, grains, and supplemental feeds necessitate changes in US beef production systems. Criollo cows that co-evolved with arid landscapes were studied as to how they interact with their environment relative to more traditional breeds. Criollo cattle traveled farther to use a greater diversity of habitat types, and spent less time near water/riparian areas compared to British breeds. Criollo cattle also mature earlier with a greater probability of reaching puberty at a younger age. These traits suggest that Criollo cattle may be a heritage breed that is well-suited for beef production systems in aridlands. (NP 215, Component 1) (Project Objective 3c)
10. Simulation modeling of vegetation dynamics: Tools are needed to integrate our knowledge base in order to understand historic dynamics and to predict future dynamics. A soil water dynamics simulation model was used to compare black grama establishment under historic (1850s) and current vegetation and soil conditions. Establishment was affected more by changes in soil properties than shifts in vegetation from grass to shrub dominance. Results can be used to identify the landscape locations where establishment is likely to be successful for remediation efforts. (NP 215, Component 1) (Project Objective 4a)
11. Integrated management, monitoring, and knowledge toolbox: An integrated suite of improved tools is needed to facilitate the synthesis, integration, and application of new and existing research. A rangeland database and simple field acquisition system that includes a wide range of assessment and monitoring tools was improved by increasing the quality of its automated indicator calculation and reporting system. Elements of a decision support framework were developed and applied to assessment, monitoring, and management of linear disturbances in rangelands (e.g., roads and off-road vehicle impacts). Elements of this toolbox are being adopted as they are developed throughout the US, increasing data quality, accessibility, and applicability to management. (NP215, Component 1) (Project Objective 4b)
5. Significant Activities that Support Special Target Populations