Centaurea Species: the Forb That Won the West

Abstract: Grasslands of the western United States and Canada are being converted to ecosystems that resemble "old fields," dominated in terms of percent cover or biomass by forb species. In particular, five species of the genus Centaurea (star thistle, diffuse, spotted, squarrose, and Russian knapweed ) have invaded millions of hectares of western United States and Canadian grasslands. Centaurea species are fundamentally different from the preexisting dominant species and may exploit changes in resource availability to become established. We suspect that they then maintain dominance by preventing resources from returning to levels that favor the native species. Increased atmospheric nitrogen deposition, reduced fire frequency, and, possibly, direct and indirect fertilization resulting from cattle grazing appear to have reduced the historically strong nitrogen limitation to which native species of western grasslands are adapted. We suggest that the success of Centaurea species in dominating grasslands is explained by their ability to compete successfully for the new limiting resource or resources. Our preliminary evidence suggests that phosphorus limitation or a colimitation of phosphorus and water best explains the current dominance patterns.     

Ocean acidification: assessing the vulnerability of socioeconomic systems in Small Island Developing States

Regional Environmental Change - Ocean acidification poses an increasing threat to marine ecosystems and also interacts with other anthropogenic environmental drivers. A planned response strategy...     

Gender and career success: A typology and analysis of dual paradigms

Despite women's advancements in the workplace, gender inequality persists. We classify and test two frameworks used to explain gender differences in career success: unequal attributes and unequal effects. The unequal attributes framework suggests that gender is related to other attributes, which result in unequal career outcomes for men and women (i.e., a mediated effect). The unequal effects framework suggests that even when men and women share the same attribute or circumstances, they are rewarded differently, such that individual attributes have unequal effects on career outcomes for men and women (i.e., a moderated effect). We collected survey data from a gender‐balanced sample of 394 business school alumni. Using structural equation modeling to test the unequal attributes framework, we found that work hours, career orientation, having a nonemployed spouse, and working in a predominantly female job were unequal attributes that explained gender differences in career success. Using multigroup path analysis to examine unequal effects, we found that being agentic, married, having children at home, and working in a predominantly female workplace had unequal effects in relation to career success for men and women. We find support for both models across three categories of career success antecedents (i.e., personal, family, and job attributes).     

Molecular tools for bathing water assessment in Europe: Balancing social science research with a rapidly developing environmental science evidence-base

The use of molecular tools, principally qPCR, versus traditional culture-based methods for quantifying microbial parameters (e.g., Fecal Indicator Organisms) in bathing waters generates considerable ongoing debate at the science–policy interface. Advances in science have allowed the development and application of molecular biological methods for rapid (~2 h) quantification of microbial pollution in bathing and recreational waters. In contrast, culture-based methods can take between 18 and 96 h for sample processing. Thus, molecular tools offer an opportunity to provide a more meaningful statement of microbial risk to water-users by providing near-real-time information enabling potentially more informed decision-making with regard to water-based activities. However, complementary studies concerning the potential costs and benefits of adopting rapid methods as a regulatory tool are in short supply. We report on findings from an international Working Group that examined the breadth of social impacts, challenges, and research opportunities associated with the application of molecular tools to bathing water regulations.     

On-road and simulated driving: concurrent and discriminant validation

Introduction

A converging pair of studies investigated the validity of a simulator for measuring driving performance/skill.

Study 1

A concurrent validity study compared novice driver performance during an on-road driving test with their performance on a comparable simulated driving test.

Results

Results showed a reasonable degree of concordance in terms of the distribution of driving errors on-road and errors on the simulator. Moreover, there was a significant relationship between the two when driver performance was rank ordered according to errors, further establishing the relative validity of the simulator. However, specific driving errors on the two tasks were not closely related suggesting that absolute validity could not be established and that overall performance is needed to establish the level of skill.

Study 2

A discriminant validity study compared driving performance on the simulator across three groups of drivers who differ in their level of experience - a group of true beginners who had no driving experience, a group of novice drivers who had completed driver education and had a learner's permit, and a group of fully licensed, experienced drivers.

Results

The findings showed significant differences among the groups in the expected direction -- the various measures of driving errors showed that beginners performed worse than novice drivers and that experienced drivers had the fewest errors. Collectively, the results of the concurrent and discriminant validity studies support the use of the simulator as a valid measure of driving performance for research purposes.

Impact on industry

These findings support the use of a driving simulator as a valid measure of driving performance for research purposes. Future research should continue to examine validity between on-road driving performance and performance on a driving simulator and the use of simulated driving tests in the evaluation of driver education/training programs.     

Cultivating hybrid collectives: research methods for enacting community food economies in Australia and the Philippines

Across the globe, groups are experimenting with initiatives to create alternatives to the dominant food system. What role might research play in helping to strengthen and multiply these initiatives? In this paper we discuss two research projects in Australia and the Philippines in which we have cultivated hybrid collectives of academic researchers, lay researchers and various non-human others with the intention of enacting community food economies. We feature three critical interactions in the “hybrid collective research method”: gathering, which brings together those who share concerns about community food economies; reassembling, in which material gathered is deliberatively rebundled to amplify particular insights; and translating, by which reassembled ideas are taken up by other collectives so they may continue to “do work”. We argue that in a climate-changing world, the hybrid collective research method fosters opportunities for a range of human and non-human participants to act in concert to build community food economies.     

Modelling remediation scenarios in historical mining catchments

Local remediation measures, particularly those undertaken in historical mining areas, can often be ineffective or even deleterious because erosion and sedimentation processes operate at spatial scales beyond those typically used in point-source remediation. Based on realistic simulations of a hybrid landscape evolution model combined with stochastic rainfall generation, we demonstrate that similar remediation strategies may result in differing effects across three contrasting European catchments depending on their topographic and hydrologic regimes. Based on these results, we propose a conceptual model of catchment-scale remediation effectiveness based on three basic catchment characteristics: the degree of contaminant source coupling, the ratio of contaminated to non-contaminated sediment delivery, and the frequency of sediment transport events.     

Advancing indigenous self-determination through endangered species protection: Idaho gray wolf recovery

As part of the right of indigenous cultures to self-determination, several international bodies have recognized and addressed the role of indigenous communities in natural resources management, including the conservation of biodiversity. In the United States, disagreements regarding the application of the federal Endangered Species Act to Native American tribes have hindered the relationship between the federal and tribal governments on endangered species recovery. Our research examines the efforts of one Native American tribe, the Nez Perce, and the United States federal government to collaborate on federal gray wolf recovery in central Idaho. We interviewed members of the Nez Perce Tribe and U.S. Fish and Wildlife Service to characterize their relationship and explore the context in which the recovery program was implemented. Respondents attributed the success of the biological aspects of wolf recovery to the robustness of the wolf as a species and to close interagency coordination at the operational level. However, differences of opinion existed between the Tribe and Service concerning program funding, policy planning, and the rights and role of the Tribe in wolf management via co-management and cooperative management regimes. Respondents from both governments noted a clear hierarchical relationship at the strategic level, where policy planning and decision-making rested with the federal government. Lessons drawn from this case study can be applied across the international spectrum to improving partnerships, particularly at the strategic level, between indigenous and non-indigenous governance structures for protecting endangered species.