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Institutions of higher education play an important role in training citizens who can thoughtfully and critically make decisions that impact the sustainability of our planet. While researchers have determined competencies that students need as environmental and sustainability professionals, less is understood about how to achieve these outcomes within complex learning environments, such as experiential learning settings. We apply a learning landscape framework to conceptualize connections among curricular and programmatic features and student learning outcomes on Dartmouth College's Environmental Studies Africa Foreign Study Program. We describe the results of 31 semi-structured interviews with alumni of the program. Results demonstrate that program design and pedagogical strategies, coupled with student activities, influence both cognitive and affective student learning outcomes, and that all learning elements are mutually influencing. Further, we identify two emergent learning outcomes, appreciation for reflection and introspection and capacity to engage with complexity, identified by considering learning at a landscape scale.

Plant invasions have tremendous potential to alter food webs by changing basal resources. Recent studies document how plant invasions may contribute to increased arthropod abundances in detritus-based food webs. An obvious mechanism for this phenomenon—a bottom-up effect resulting from elevated levels of detritus from the invasive plant litter—has not been explicitly studied. We examined the effects of an annual grass invasion on ground arthropod assemblages in the coastal sage scrub (CSS) of southern California. Bottom-up food web theory predicts that the addition of detritus would increase generalist-feeding arthropods at all trophic levels; accordingly, we expected increases in fungi, Collembola, and common predators such as mites and spiders. For the common ant taxa, habitat alteration may also be important for predicting responses. Thus we expected that Forelius mccooki and Pheidole vistana, the most common ant species, would decline because of changes in soil temperature (F. mccooki) and habitat structure (P. vistana) associated with litter. We studied trends observationally and conducted a 3-year experiment in which we manipulated litter quantity. In contrast to other published studies, most detritus-based arthropod taxa declined in areas of high grass invasion, and, within trophic levels, responses often varied idiosyncratically. For the two most common taxa, a native ant (F. mccooki), and predatory mites in the Anystidae, we experimentally linked declines in abundance to increased levels of invasive grass litter. Such declines, especially those exhibited by the most common ant taxa, could have cascading effects on the CSS ecosystem, where ants are numerically dominant and thus may have broad influences on food web and ecosystem properties. Our results highlight that accurately predicting arthropod responses to invasive plant litter requires careful consideration of the structural and food resources provided by detritus to each particular food web.

Community-based natural resource management (CBNRM) seeks to align the interests of local communities and conservation institutions. A significant challenge to this realignment is that CBNRM is often implemented in locations with colonial histories of oppression, persecution, and dispossession that have left legacies of inequity and marginalization. Social networks are one method for discerning how marginalized CBNRM actors can negotiate entitlements and agency. Through the lens of social networks, marginalization can be viewed as insufficient connectivity between the center and the periphery of the network. One possible remedy to this dysfunction are boundary actors, which are thought to be vital to connecting parts of social networks that would otherwise be poorly connected. Using social network analysis to visualize interactions between the Topnaar community and CBNRM institutional actors in Namibia's Namib-Naukluft and Dorob National Parks, we find a number of individuals well-positioned to serve as boundary actors. Although our results suggest these individuals can be effective in sharing and translating key knowledge, supporting transfers of benefits, and enabling or negotiating entitlements, we also found that social, political, institutional, and geographic constraints limited their effectiveness. In particular, the Topnaar Traditional Authority, adopted a "neo-traditional," top-down, gatekeeper role, while their community wanted them to be more responsive and engaged in directly addressing the communities' problems. In general, the boundary actors were the focus of much discontent and conflict, in large part because of unclear pathways of accountability. We recommend the co-creation of boundary objects that specify responsibilities and thus reduce conflict and support effective boundary actors. [ABSTRACT FROM AUTHOR]

The competitive displacement by a sexual gecko species of an asexual resident gecko has been documented over a wide geographic area. To test hypotheses concerning the detailed mechanism of this [...]