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{"Abstract":["Water masks, river centerlines and river widths measured and generated for analysis for The Widths of Rivers and Streams Across Spatial Scales. Water masks are labelled as "river = 255", "lake/reservoir = 128", and "canal = 64" and are presented as .tif files with associated .tfw files; river centerline data are presented as .shp files with associated .dbf, .shx, and .prj files or as .kmz files; river width data are presented as .csv files."]} 

Abstract The width of rivers, and how it scales from narrow headwater streams to wide basin outlets, is a key yet highly uncertain parameter in estimating river‐atmosphere biogeochemical exchange. This study characterizes the full distribution of river widths across all stream orders in the Mississippi River Basin using multi‐source remote sensing, field surveying, and a nested sampling approach. River widths within each stream order consistently follow a log‐normal distribution. When integrated with basin‐wide river network lengths, these width distributions combine to form an emergent Pareto distribution. Using this newfound width scaling framework for the Mississippi Basin, we estimate a sum river surface area of 17,828 ± 2,563 km², an area broadly consistent with previous evaluations. This study's refined characterization of river widths across scales has wide‐ranging applications including a more accurate accounting of river and stream surface area with implications for global river‐atmosphere biogeochemical exchange assessments. 

Islands have often been used to exile political prisoners, migrants, criminals, mentally ill individuals, and others deemed unworthy. Yet the remoteness that made islands ideal prison sites is today exploited to develop nature-based ecotourism (NBET). Given the ‘prison to paradise’ phenomenon is previously undocumented in the literature, this paper explores three descriptive cases in the Global South: Ecuador (Galápagos Islands), Panamá (Coiba Island), and Colombia (Gorgona Island). This analysis identifies how the timelines of prison activities and the manifestations of tourism are influenced by contextual factors that determine whether carceral heritage is being preserved or overwritten in each context. The paper also highlights further opportunities to elaborate on this nascent theory and emphasise specific roles for archaeologists in that future research agenda. This work will appeal to scholars interested in dark heritage, prison tourism, island studies, and protected area managers involved with heritage preservation around former prison sites. 

Antarctic ice cores provide a unique archive of Earth’s atmosphere and its largest extant ice sheet. The oldest continuous ice core extends back 800 ky, though discontinuous ice cores from the Allan Hills blue ice area (BIA) have been shown to preserve snapshots of ice and air back to at least 2.7 million years ago (Ma). Here, we provide snapshots of putatively Miocene and Pliocene ice and air from shallow ice cores drilled in the Allan Hills BIA. The ice, dated using the deficit in⁴⁰Ar in ancient air compared to the modern atmosphere, is stratigraphically complex. Nevertheless, surface temperatures inferred from water isotopes correlate with sample age and indicate 12 ± 2 °C of cooling in Antarctica between 6 Ma and the late Pleistocene. Basal ice is nearly devoid of gases and remains to be dated with existing methods. This undated ice is characterized by an isotopic temperature 5 ± 1 °C warmer than the oldest dated (6 million year old) sample. We speculate that this ice reflects surface snowpack or permafrost that was preserved by the growth of the East Antarctic ice sheet in the Middle to Late Miocene. 

Recent studies identifying underlying and proximate drivers of tropical deforestation and forest degradation have applied a multitude of methodologies, with varying and sometimes conflicting results. Divergent results can have implications for evidence-informed programs, policy action, and land use planning since these differences can lead to controversy as to which drivers should be addressed by deforestation and emissions-reduction or conservation programs, in addition to mismatch between the scale of study results and the scale of policy and program implementation. To identify and reconcile divergences between results among different scales and methodological approaches, we systematically reviewed 231 articles in the drivers of deforestation literature and found inconsistency in scale applied within studies (e.g., differences between the stated scale of analysis and scale of article recommendations), and variation in the number and type of drivers identified between studies by methodology. Additionally, global and regional studies tended to feature recommendations that would be difficult to implement, or that targeted large-scale problems lacking specificity. This study clarifies common themes in driver identification and what is needed for drawing contextualized, scale-appropriate conclusions relevant to forest conservation policy and sustainable land use planning. We suggest improvements to recommendations drawn from drivers of deforestation studies and avenues to reconcile divergences in approaches and results, which will support efforts to advance forest conservation and sustainable forest management outcomes. 

Recent advances in passive structural control systems have included devices that exploit nonlinear behavior. The explicit inclusion of nonlinearities allows these passive devices to be designed to have behavior and performance that varies with different load types and amplitudes. The variable inertial rotational mechanism (VIRM) is an example of a nonlinear passive control device and consists of a mechanism that converts linear motion into rotational motion and an attached flywheel that includes masses that can move radially inside the flywheel. The radial motion of the VIRM flywheel masses results in the flywheel moment of inertia continuously varying during the response of the device. Despite a potentially small physical mass, the VIRM can provide to a system large added mass effects that can vary greatly depending on the flywheel moment of inertia. The large and variable mass effects provided by the VIRM can significantly shift the natural frequency and reduce the response amplitude of an underlying structure. While the VIRM has been investigated numerically by a number of authors, the experimental study of these devices has been limited. Moreover, most of the studies have considered semi-active or active variable inertia flywheels. The investigation of passive VIRMs are rare. This study aims to address these gaps in knowledge and experimentally investigate the response modification and pseudo resonance frequency changes of an underlying structure produced by the VIRM considering different loading conditions. For this experimental investigation, a VIRM was designed and fabricated that utilizes a lead screw and a flywheel that contains masses connected to springs that can move radially in the flywheel. This VIRM was then attached to a single-degree-of-freedom structure and subjected to different excitation types using a shake table. With data from these experimental tests, the overall fundamental frequency and the response of the system was evaluated using the experimentally estimated system transfer functions. The results of this study shows that the inclusion of the VIRM reduces the response amplitude and significantly shifted the pseudo resonance frequency of the underlying structure and that these shifts in pseudo resonance frequency are highly dependent on the loading amplitude. 

This paper offers paradigmatic insights from an international workshop on Ecological Legacies: Bridge Between Science and Community, in Ecuador, in the summer of 2023. The conference brought together foreign and local scholars, tour operators, village community, and Indigenous leaders in the upper Amazonia region of Ecuador with the goal of developing a vision for a sustainable and regenerative future of the upper Amazon. The conference offered three epistemological contributions to the existing literature in the emergent field of Montology, including addressing issues of (a) understanding the existing linguistic hegemony in describing tropical environments, (b) the redress of mistaken notions on pristine jungle environments, and (c) the inclusion of traditional knowledge and transdisciplinary approaches to understand the junglescape from different perspectives and scientific traditions. Methodologically, the conference bridged the fields of palaeoecological and ethnobotanical knowledge (as part of a wider conversation between science and local communities). Results show that local knowledge should be incorporated into the study of the junglescape and its conservation, with decolonial approaches for tourism, sharing language, methodology, tradition, and dissemination of the forest’s attributes. Our research helped co-create and formulate the “Coca Declaration” calling for a philosophical turn in research, bridging science and ethnotourism in ways that are local, emancipatory, and transdisciplinary. We conclude that facilitating new vocabulary by decolonial heightening of Indigenous perspectives of the junglescape helps to incorporate the notion of different Amazons, including the mountainscape of the Andean–Amazonian flanks. We also conclude that we can no consider Ecuador the country of “pure nature” since we helped demystify pristine nature for foreign tourists and highlighted local views with ancestral practices. Finally, we conclude that ethnotourism is a viable alternative to manage heritagization of the junglescape as a hybrid territory with the ecological legacies of the past and present inhabitants of upper Amazonia. 

Biocultural approaches to restoration, which recognize the unique ways of understanding of socioecological challenges by Indigenous and local communities, have gained traction in recent decades. Yet, less attention has focused on biocultural opportunities where there is no Indigenous population or traditional knowledge to draw upon. This ethnographic study inductively assesses data gathered from interviews with farm owners on Isabela Island in the Galápagos Islands, where human presence is a function of recent migration. These interviews, corroborated with archival information and participant observation, center on farmer attitudes regarding restoration of Scalesia cordata, a highly endangered plant species, endemic to Isabela. The resulting analysis identified four themes of overlap with the biocultural restoration literature: cultural keystone species, sense of place, informational pathways, and recognition of socio-ecological feedback loops. Findings indicate that Scalesia remains a valued cultural keystone species providing tangible and intangible benefits to local residents, and its survival serves as a metaphor for farmers’ own wellbeing. Thus, even locations where place-based knowledge by a native population is not evident, critical biocultural elements exist that can be integrated into restoration efforts. Farmers also exhibited clear connections between restoration and tourism in Galápagos, paving the way for the application of biocultural theory to the analysis of tourism-supported restoration efforts elsewhere. 

Latin America is where ecotourism got an early start, and where it remains best represented today. In this essay, brief comparative cases, from the Galápagos to Costa Rica, demonstrate how understanding the value of ecotourism requires consideration of the alternative economic activities and forms of tourism likely to occur in its absence. By distinguishing its relative effectiveness as a strategy for meeting human needs while protecting the environment, we can better understand why the committed application of ecotourism remains a major conservation strategy that environmentalists are promoting over the alternatives and implementing across Latin America.