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1.
Lack of long-term ecological monitoring presents a challenge for sustainable rangeland management in many areas of the western United States. Ranchers and other land managers have local knowledge gained from ongoing experience in specific places that could be useful for understanding ecological change and best management practices. Local knowledge is defined as knowledge gained by daily contact with the natural world and ecological processes. Unfortunately, little is known about ranchers’ local knowledge, and few studies have systematically examined the types, depth, and validity of this knowledge. Ranch memoirs offer an unexplored entry into rancher knowledge acquisition, categories, and context. In this study, we coded and analyzed eighteen ranch memoirs from the western United States to investigate the specific types, depth, and quality of local land knowledge. We found that ranchers possess knowledge of both management and ecology, and that these knowledge realms are intertwined and often inseparable. In addition to learning from experience, social interactions are an important part of rancher education and create a shared knowledge culture. In most of the memoirs, ranchers revealed very little knowledge of long-term patterns of vegetation change. In all the memoirs reviewed, ranchers articulated a deep sense of responsibility and connectedness to the landscapes they manage and steward. This review of ranch memoirs provides a framework for future studies of local knowledge by identifying how ranchers gain their knowledge of the landscapes they manage, describing some of the distinctive types of knowledge that ranchers possess, and challenging conventional classifications of rancher knowledge.  相似文献   

2.
State-and-transition models (STMs) depict current understanding of vegetation dynamics and are being created for most ecological sites in the United States. Model creation is challenging due to inadequate long-term data, and most STMs rely on expert knowledge. There has been little systematic documentation of how different types of knowledge have been integrated in STMs, or what these distinct knowledge sources offer. We report on a series of participatory workshops where stakeholders helped to integrate STMs developed for the same region using local knowledge and ecological field data. With this exploratory project, we seek to understand what kinds of information local knowledge and ecological field data can provide to STMs, assess workshops as a method of integrating knowledge and evaluate how different stakeholders perceive models created with different types of knowledge. Our analysis is based on meeting notes, comments on draft models, and workshop evaluation questionnaires. We conclude that local knowledge and ecological data can complement one another, providing different types of information at different spatial and temporal scales. Participants reported that the workshop increased their knowledge of STMs and vegetation dynamics, suggesting that engaging potential model users in developing STMs is an effective outreach and education approach. Agency representatives and ranchers expressed the value of both the local knowledge and data-driven models. Agency participants were likely to critique or add components based on monitoring data or prior research, and ranchers were more likely to add states and transitions based on personal experience. As STM development continues, it is critical that range professionals think systematically about what different forms of data might contribute to model development, how we can best integrate existing knowledge and data to create credible and useful models, and how to validate the resulting STMs.  相似文献   

3.
For more than 150 years, ranchers in the West have gained insight about natural systems through daily interaction and management of landscapes, but this knowledge has never been systematically documented and analyzed. We interviewed 26 ranchers from a single watershed to understand how ranchers acquire their knowledge, document what they know about rangeland ecosystems, and explore how this knowledge varies within the ranching community. This exploratory study offers insight into the types of knowledge ranchers possess without attempting to survey all rancher knowledge or ascribe this set of knowledge to all ranchers. We identified three major knowledge categories in interviews: active knowledge applied to management decisions, embedded knowledge from living in place, and integrative knowledge that links ecological, economic, and social aspects of rangeland systems. We found rancher knowledge complemented scientific knowledge in its ability to provide site-specific information on management practices and ecological responses, and insight regarding potential indicators of rangeland health. Knowledge varies widely within the ranching community, and knowledgeable ranchers are readily identified through community referrals. Ranchers gained their knowledge primarily through experience and social interactions, and this knowledge is an untapped source of context-specific information. We did find that economic constraints, social norms, and proximity to the system might limit application of knowledge to practice. There is also a danger that this accumulated and dynamic knowledge base will be lost over the next generation, as many family ranches are sold to new ranchers or for nonranching uses. Based on our findings, we propose that more dialogue within ranching communities and between ranchers and scientists may lead to more sustainable land management practices and effective outreach efforts, and could expand and strengthen the informal social networks through which much rancher knowledge is shared and on which the social sustainability of ranching communities depends.  相似文献   

4.
State-and-transition models (STMs), conceptual models of vegetation change based on alternate state theory, are increasingly applied as tools for land management decision-making. As STMs are created throughout the United States, it is crucial to ensure that they are supported by ecological evidence. Plant species composition reflects ecosystem processes that are difficult to measure and may be a useful indicator of alternate states. This study aims to create data-driven STMs based on plant species composition for two ecological sites (Claypan and Mountain Loam) in northwestern Colorado sagebrush steppe. We sampled 76 plots with different management and disturbance histories. Drawing on the hierarchical approach currently taken to build STMs, we hypothesized that A) differences in species composition between the two ecological sites would be related to environmental factors and B) differences in species composition within each ecological site would be related to management and disturbance history. Relationships among species composition, site history, and environmental variables were evaluated using multivariate statistics. We found that between ecological sites, species composition was related to differences in soil texture, supporting Hypothesis A and the creation of separate STMs for each site. Within ecological sites, species composition was related to site history and also to environmental variation. This finding partially supports Hypothesis B and the identification of alternate states using species composition, but also suggests that these ecological sites are not uniform physical templates upon which plant community dynamics play out. This data-driven, plant species–based approach created two objective, credible STMs with states and transitions that are consistent with the sagebrush steppe literature. Our findings support the hierarchical view of landscapes currently applied in building STMs. An approach that acknowledges environmental heterogeneity within ecological sites is necessary to help define finer-resolution ecological sites and elucidate cases in which specific abiotic conditions make transitions between states more likely.  相似文献   

5.
The broad-scale assessment of natural resource conditions (e.g., rangeland health, restoration needs) requires knowledge of their spatial distribution. We argue that creating a database that links state-and-transition models (STMs) to spatial units is a valuable management tool for structuring ground-based observations, management planning for landscapes, and for housing information on the responses of land areas to management actions. To address this need, we introduce a multifactor classification system based on ecological sites and STMs that is directly linked to recent concepts of vegetation dynamics in rangelands. We describe how this classification was used as a basis for creating a spatial database and maps of ecological states. We provide an example of how the classification and mapping has been applied in over 1.2 million ha of public rangelands in southern New Mexico using aerial photo interpretation supplemented with existing inventory data and rapid field assessments. The resulting state map has been used by the Bureau of Land Management: 1) to design landscape-level shrub control efforts, 2) to structure and report district-wide rangeland health assessments, and 3) to evaluate locations for energy development. We conclude by discussing options for the development of state maps and their current limitations, including the use of satellite imagery and concepts for defining states. We argue that cataloging ecological states in a spatial context has clear benefits for rangeland managers because it connects STM concepts to specific land areas. State mapping provides a means to generate and store spatially explicit data resulting from tests of the propositions in STMs and conservation practices.  相似文献   

6.
State-and-transition models (STMs) are being developed for many areas in the United States and represent an important tool for assessing and managing public and private rangelands. Substantial resources have been invested in model development, yet minimal efforts have been made to evaluate the utility of STMs for rangeland assessment and management. We interviewed 47 rangeland professionals, equally divided between managers and researchers, in four ecoregions to determine their perceptions of the purpose, development, and strengths and weaknesses of STMs to assess the status of the STM framework. Our analysis identified three primary perspectives regarding the purpose of STMs: a decision-making tool for land managers, a means to represent the complex dynamics of rangeland ecosystems, and an effective communication tool. These diverse views of STM purposes were associated with differing perspectives concerning model development that identified five major issues in need of further development and refinement: 1) the relative importance of management practices and ecological processes in driving transitions, 2) the criteria used to define thresholds, 3) the appropriate level of model complexity, 4) the respective roles of expert knowledge and ecological data in model development, and 5) processes for model review and revision. We recommend greater dialogue among researchers and managers to further clarify STM terminology and develop standard protocols for model development and validation. Mechanisms are critically needed to assure peer review and revision of existing models so that STMs are continually updated to reflect current understanding of rangeland dynamics.  相似文献   

7.
Interpretation of assessment and monitoring data requires information about how reference conditions and ecological resilience vary in space and time. Reference conditions used as benchmarks are often specified via potential-based land classifications (e.g., ecological sites) that describe the plant communities potentially observed in an area based on soil and climate. State-and-transition models (STMs) coupled to ecological sites specify indicators of ecological resilience and thresholds. Although general concepts surrounding STMs and ecological sites have received increasing attention, strategies to apply and quantify these concepts have not. In this paper, we outline concepts and a practical approach to potential-based land classification and STM development. Quantification emphasizes inventory techniques readily available to natural resource professionals that reveal processes interacting across spatial scales. We recommend a sequence of eight steps for the co-development of ecological sites and STMs, including 1) creation of initial concepts based on literature and workshops; 2) extensive, low-intensity traverses to refine initial concepts and to plan inventory; 3) development of a spatial hierarchy for sampling based on climate, geomorphology, and soils; 4) stratified medium-intensity inventory of plant communities and soils across a broad extent and with large sample sizes; 5) storage of plant and soil data in a single database; 6) model-building and analysis of inventory data to test initial concepts; 7) support and/or refinement of concepts; and 8) high-intensity characterization and monitoring of states. We offer a simple example of how data assembled via our sequence are used to refine ecological site classes and STMs. The linkage of inventory to expert knowledge and site-based mechanistic experiments and monitoring provides a powerful means for specifying management hypotheses and, ultimately, promoting resilience in grassland, shrubland, savanna, and forest ecosystems.  相似文献   

8.
Experiments investigating grazing systems have often excluded ranch-scale decision making, which has limited our understanding of the processes and consequences of adaptive management. We conducted interviews and vegetation monitoring on 17 ranches in eastern Colorado and eastern Wyoming to investigate rancher decision-making processes and the associated ecological consequences. Management variables investigated were grazing strategy, grazing intensity, planning style, and operation type. Ecological attributes included the relative abundance of plant functional groups and categories of ground cover. We examined the environmental and management correlates of plant species and functional group composition using nonmetric multidimensional scaling and linear mixed models. After accounting for environmental variation across the study region, species composition did not differ between grazing management strategy and planning style. Operation type was significantly correlated with plant community composition. Integrated cow-calf plus yearling operations had greater annual and less key perennial cool-season grass species cover relative to cow-calf  only operations. Integrated cow-calf plus yearling ranches were able to more rapidly restock following drought compared with cow-calf operations. Differences in types of livestock operations contributed to variability in plant species composition across the landscape that may support diverse native faunal species in these rangeland ecosystems. Three broad themes emerged from the interviews: 1) long-term goals, 2) flexibility, and 3) adaptive learning. Stocking-rate decisions appear to be slow, path-dependent choices that are shaped by broader social, economic, and political dynamics. Ranchers described having greater flexibility in altering grazing strategies than ranch-level, long-term, annual stocking rates. These results reflect the complexity of the social-ecological systems ranchers navigate in their adaptive decision-making processes. Ranch decision-making process diversity within these environments precludes development of a single “best” strategy to manage livestock grazing.  相似文献   

9.
State-and-transition models (STMs) are used in natural resource management to describe ecological site scale response to natural and anthropogenic disturbances. STMs are primarily based for expert opinion and literature reviews, lacking analytical testing to support vegetation community dynamics, thresholds, and state changes. We developed a unique approach, combining ordination and permutation MANOVA (perMANOVA) with raw data interpretation, to examine vegetation data structure and identify thresholds for a STM. We used a long-term monitoring dataset for an ecological site on the Santa Rita Experimental Range, Arizona. Basal cover of perennial grasses and canopy cover of shrubs and cacti were measured on permanent transects beginning in 1957. Data were grouped by drivers identified by the STM including species invasion, grazing, drought, and mesquite treatment. Ordination by nonmetric multidimensional scaling described the structure of the data. PerMANOVA was used to test for differences between groups of sample units. Analyses of combined key species (Lehmann's lovegrass and mesquite [Prosopis velutina Woot.]) and nonkey species patterns demonstrated an irreversible transition and occurrence of a structural threshold due to Lehmann's lovegrass invasion, as well as a short-term reversible transition (restoration pathway) following mesquite treatment. Sensitivity analysis, in which key species were removed from the dataset, showed that the relative composition of nonkey species did not differ between states previously defined by the key species. This apparent disconnect between dynamics of key and nonkey species may be related to changes in the functional attributes that were not monitored during this time series. Our analyses suggest that, for this ecological site, transition to a Lehmann's lovegrass state occurs when basal cover of this species exceeds 1–2%, which often occurs within 6 yr of its arrival. Evaluation of the restoration pathway showed a recrossing of the threshold within 6 yr of treatment and when mesquite canopy cover exceeded 10%.  相似文献   

10.
11.
Access to the Internet continues to grow in rural areas, ensuring ranchers will have increasing opportunities to use the Web to find information about management practices that may provide them ecological and financial benefits. Although past studies have examined the role of the Internet in informing daily decision making by agricultural producers, no studies have focused specifically on the use of the Internet by ranchers in the western United States. This study uses a mixed-methods approach (a survey and semistructured interviews) to assess the extent and patterns of ranchers’ Internet use in Colorado and Wyoming, identify barriers to greater use, and establish a typology of Web use behavior by ranchers. Our findings indicate that Internet use is widespread and that age, education, and risk tolerance predict the extent to which a rancher will rely on the Internet for day-to-day ranch management. A cluster analysis delineated four distinct types of Web usage among ranchers: uninfluenced, focused on sales and herd management, moderately influenced, and an Internet-reliant type. Outreach personnel can use this classification to determine the potential utility of digital outreach tools for their programming on the basis of their target audience and outreach topics.  相似文献   

12.
13.
The objective of this paper is to recommend conceptual modifications for incorporation in state-and-transition models (STMs) to link this framework explicitly to the concept of ecological resilience. Ecological resilience describes the amount of change or disruption that is required to transform a system from being maintained by one set of mutually reinforcing processes and structures to a different set of processes and structures (e.g., an alternative stable state). In light of this concept, effective ecosystem management must focus on the adoption of management practices and policies that maintain or enhance ecological resilience to prevent stable states from exceeding thresholds. Resilience management does not exclusively focus on identifying thresholds per se, but rather on within-state dynamics that influence state vulnerability or proximity to thresholds. Resilience-based ecosystem management provides greater opportunities to incorporate adaptive management than does threshold-based management because thresholds emphasize limits of state resilience, rather than conditions that determine the probability that these limits will be surpassed. In an effort to further promote resilience-based management, we recommend that the STM framework explicitly describe triggers, at-risk communities, feedback mechanisms, and restoration pathways and develop process-specific indicators that enable managers to identify at-risk plant communities and potential restoration pathways. Two STMs representing different ecological conditions and geographic locations are presented to illustrate the incorporation and application of these recommendations. We anticipate that these recommendations will enable STMs to capture additional ecological information and contribute to improved ecosystem management by focusing attention on the maintenance of state resilience in addition to the anticipation of thresholds. Adoption of these recommendations may promote valuable dialogue between researchers and ecosystem managers regarding the general nature of ecosystem dynamics.  相似文献   

14.
Private landowners are often de facto stewards of biodiversity and ecosystem services. In California's Sierra Nevada foothills, ranchers frequently present the only defense against biological invasions in private rangelands. Although ranchers' land management goals (e.g., the desire to control invasive species) can be consistent with ecosystem protection, practical constraints often limit their success. Considerable research on the invasive weed, yellow starthistle (Centaurea solstitialis L.), has produced numerous control strategies. Nevertheless, the range of this noxious weed continues to increase. We used surveys and interviews to document the weed control efforts of 202 ranchers and to identify practical limitations to their efficacy. Overall, 86% of ranchers who had experienced yellow starthistle infestation had attempted control, using one or more of 19 methods. Early response reduced negative effects from yellow starthistle. Control methods learned from agricultural advisors were reported more effective than those learned elsewhere. Limitations to yellow starthistle control in our study population resulted from incomplete information regarding control methods, complexity of weed control in heterogeneous landscapes, inconsistent application of methods, and lack of long-term planning for weed control. Such hindrances make it difficult for landowners to implement control methods promoted by researchers. This gap between science and practice contributes to the continued increase of yellow starthistle within the study region. To shrink this gap, researchers and agricultural advisors can incorporate environmental heterogeneity into applied agricultural research, use land stewards' knowledge and experience, and increase public education.  相似文献   

15.
16.
This paper analyzes rancher participation in conservation programs in the context of a social-ecological framework for adaptive rangeland decision-making. We argue that conservation programs are best understood as one of many strategies of adaptively managing rangelands in ways that sustain livelihoods and ecosystem services. The framework hypothesizes four categories of variables affecting conservation program participation: operation/operator characteristics, time horizon, social network connections, and social values. Based on a mail survey of California ranchers, multinomial logit models are used to estimate the impact of these variables on different levels of rancher involvement in conservation programs. The findings suggest that ranchers with larger amounts of land, an orientation towards the future, and who are opinion leaders with access to conservation information, are more likely to participate in conservation programs.  相似文献   

17.
US natural resources and wildlife agencies have been increasing their efforts to involve cattle ranchers in wildlife conservation through technical assistance programs that provide for wildlife conservation activities. Understanding why ranchers choose to be involved in these programs is fundamental to increasing participation and ensuring their success. Using the theory of planned behavior as a theoretical model, we surveyed 1 093 ranchers in Alabama, Florida, Georgia, and Mississippi to explain and predict intention to participate in technical assistance programs, specifically, wildlife workshops and field days. All three theory components—attitude, subjective norm, and perceived behavioral control—were important to intent to participate and explained 41% of the variance, with perceived behavioral control and subjective norm having the greatest standardized effects (β = 0.329 and β = 0.316, respectively). Investigation of the construct components yielded insight into how agencies could increase participation. Ranchers generally held positive attitudes toward wildlife workshops, perceiving them to be a good way to learn about wildlife management and perceiving that most ranches were suitable for wildlife, an instance of perceived behavioral control. However, ranchers did not perceive that workshops and field days were widely advertised or promoted, limiting the amount of perceived control they had over their participation. Additionally, ranchers identified normative groups whose opinions were important to them, namely their families, friends and neighbors, fellow ranchers, and agency staff. However, these same groups were not seen to actively encourage ranchers to participate in technical field days and workshops. Using key members of these normative groups to advertise and promote workshops and field days among their peers should increase rancher behavioral control and attitudes associated with technical workshops and field days. Employing strategies from this research to increase attendance at technical workshops and field days should improve wildlife conservation technical assistance program effects.  相似文献   

18.
19.
The past decade has seen a rapid rise in beaver-related stream restoration (BRR) using beavers and beaver dams (real or artificial) as a tool. Potential benefits of this low-cost, nature-based restoration approach include restoring aquatic and riparian habitat and recovering of threatened species dependent on it, improving water availability and stream flow regulation, reducing erosion and stream incision, and supporting climate change adaptation. Although the ecological restoration literature acknowledges the importance of addressing the human dimensions of restoration, there is a gap regarding the human dimensions of BRR. To help fill this gap we examined six projects involving riparian revegetation or artificial beaver dams to identify central elements of a supportive social environment for BRR on western rangelands. Our research questions examined how beavers, beaver dams, and BRR affect ranching operations and how ranchers view them; the policy context for BRR; and how BRR practitioners, regulatory agencies, ranchers, and partners work together for successful BRR. We synthesized our findings across cases and identified six social factors important for BRR: 1) ranchers who perceive the benefits of beavers, beaver dams, and BRR to outweigh the drawbacks; 2) education and assistance to help landowners adopt nonlethal mitigation techniques for nuisance beavers; 3) grazing practices compatible with BRR; 4) low harvest pressure on beavers; 5) a regulatory environment that enables experimentation, flexibility, and adaptive management; and 6) proponents, ranchers, and partners willing to take risks, innovate, be flexible, and stay committed.  相似文献   

20.
Crossing disciplinary boundaries, particularly between social and ecological sciences, challenges those seeking to contribute to solving complex and multidimensional environmental problems on rangelands. In this Special Issue we present a set of 13 papers that to varying degrees attempt to integrate, or bring together, diverse approaches across disciplines to understand silvopastoral systems. The papers are about rangelands in numerous countries and regions, including Spain, Estonia, Greece, Germany, Hungary, Italy, Portugal, Romania, the United States, Latin America, and Sweden. Silvopastoral systems provide ecosystem goods and services important to communities, cultures, and society. Management deliberately exploits the diversity fostered by rangeland systems that mix woody species with a well-developed herbaceous understory, offering a greater diversity of products, species, vegetation structural characteristics, and habitat components than either grassland or forest. Biodiversity often peaks at the intermediate levels of tree and shrub cover characteristic of silvopastoral systems. We introduce the papers grouped by four overarching topics: 1) typologies and scales, 2) social-ecological interactions, 3) integrated management, and 4) multiple knowledge systems. Unfortunately, silvopastoral systems often run afoul of ongoing intensification and simplification trends in agricultural production that reduce their economic and ecological resilience. Privately owned systems, the most common in this issue, are subject to the need for owner income. Finding ways to support the benefits of these systems for the public is difficult, as management traditions must be conserved as well as the land. We hope this issue illustrates the value of multifunctional systems and offers insights into how they work.  相似文献   

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