365 research outputs found

    Respect for Grizzly Bears: An Aboriginal Approach for Co-existence and Resilience

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    Aboriginal peoples’ respect for grizzly bear (Ursus arctos) is widely acknowledged, but rarely explored, in wildlife management discourse in northern Canada. Practices of respect expressed toward bears were observed and grouped into four categories: terminology, stories, reciprocity, and ritual. In the southwest Yukon, practices in all four categories form a coherent qualitative resource management system that may enhance the resilience of the bear-human system as a whole. This system also demonstrates the possibility of a previously unrecognized human role in maintaining productive riparian ecosystems and salmon runs, potentially providing a range of valued social-ecological outcomes. Practices of respect hold promise for new strategies to manage bear-human interactions, but such successful systems may be irreducibly small scale and place based

    Science for Place-based Socioecological Management: Lessons from the Maya Forest (Chiapas and Petén)

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    The role humans should play in conservation is a pervasive issue of debate in environmental thinking. Two long-established poles of this debate can be identified on a preservation-sustainable use continuum. At one extreme are use bans and natural science-based, top-down management for preservation. At the other extreme is community-based, multidisciplinary management for sustainable resource use and livelihoods. In this paper, we discuss and illustrate how these two strategies have competed and conflicted in conservation initiatives in the Maya forest (MF) of the Middle Usumacinta River watershed (Guatemala and Mexico). We further argue that both extremes have produced unconvincing results in terms of the region’s sustainability. An alternative consists of sustainability initiatives based on place-based and integrated-knowledge approaches. These approaches imply a flexible combination of disciplines and types of knowledge in the context of nature-human interactions occurring in a place. They can be operationalized within the framework of sustainability science in three steps: 1) characterize the contextual circumstances that are most relevant for sustainability in a place; 2) identify the disciplines and knowledge(s) that need to be combined to appropriately address these contextual circumstances; and 3) decide how these disciplines and knowledge can be effectively combined and integrated. Epistemological flexibility in the design of analytic and implementation frameworks is key. Place-based and integrative-knowledge approaches strive to deal with local context and complexity, including that of human individuals and cultures. The success of any sustainability initiative will ultimately depend on its structural coupling with the context in which it is applied

    Learning from community forestry experience: Challenges and lessons from British Columbia

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    A multiple case study approach is used to investigate community forest implementation challenges in British Columbia, Canada. Stakeholder interviews, document review and visits to the case sites (Denman Island, Malcolm Island, Cortes Island and Creston) were used to collect data on events occurring between 1990 and 2005. In addition to case-specific challenges, our analysis confirmed common challenges related to a lack of support, consensus, and organizational resources as well as poor forest health and timber profiles, resistance from conventional forest management, and competition for land and tenures. Development pressure emerged as a challenge for communities without land use decisionmaking authority. The final section offers some lessons and recommendations. / Une approche d’études de cas multiples est utilisée pour étudier les défis découlant de l’implantation de forêts communautaires en Colombie-Britannique, Canada. Nous avons effectué des entrevues auprès des intervenants, une revue des documents et des visites sur le terrain (Denman Island, Malcolm Island, Cortes Island et Creston) afin de recueillir des données sur les événements survenus entre 1990 et 2005. En plus des défis spécifiques à chaque cas, notre analyse a confirmé des défis communs reliés à la faiblesse des appuis, à un consensus mitigé et un manque de ressources organisationnelles ainsi qu’un mauvais état de santé des forêts et une pauvre répartition de la qualité au niveau des tiges, à la résistance par rapport à l’aménagement forestier conventionnel et à la compétition pour l’utilisation du territoire et la forme de tenure. Les communautés n’ayant pas d’autorité en matière de prise de décision sur l’utilisation du territoire ont connu l’émergence de défis face à des pressions de développement. La dernière section présente quelques leçons et recommandations.Support for this work has been provided by the Social Sciences and Humanities Research Council and inkind support has been generously provided by Western Forest Products.http://pubs.cif-ifc.org/doi/10.5558/tfc85293-

    Chimpanzees Extract Social Information from Agonistic Screams

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    Chimpanzee (Pan troglodytes) agonistic screams are graded vocal signals that are produced in a context-specific manner. Screams given by aggressors and victims can be discriminated based on their acoustic structure but the mechanisms of listener comprehension of these calls are currently unknown. In this study, we show that chimpanzees extract social information from these vocal signals that, combined with their more general social knowledge, enables them to understand the nature of out-of-sight social interactions. In playback experiments, we broadcast congruent and incongruent sequences of agonistic calls and monitored the response of bystanders. Congruent sequences were in accordance with existing social dominance relations; incongruent ones violated them. Subjects looked significantly longer at incongruent sequences, despite them being acoustically less salient (fewer call types from fewer individuals) than congruent ones. We concluded that chimpanzees categorised an apparently simple acoustic signal into victim and aggressor screams and used pragmatics to form inferences about third-party interactions they could not see

    Defining plant resistance against Phytophthora Cinnamomi and application of resistance to revegetation

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    Phytophthora cinnamomi is a soil borne plant pathogen that causes devastating disease in many Australian ecosystems and threatens the survival of native flora. Compared with the number of plant species that are susceptible to P. cinnamomi, only a few species are known to be resistant and control of this pathogen by chemicals is difficult and undesirable in natural systems. The major aim of our research is therefore to characterise natural resistance and determine which signalling pathways and defence responses are involved. Our examination of resistance is being approached at several levels, one of which is through the use of the model plant, Arabidopsis. Previously, Arabidopsis had been shown to display ecotypic variation in responses to P. cinnamomi and we are exploring this further in conjunction with the analysis of a bank of Arabidopsis defence pathway mutants for their responses to the pathogen. These experiments will provide a fundamental basis for further analysis of the defence responses of native plants. Native species (susceptible and resistant) are being assessed for their responses to P. cinnamomi at morphological, biochemical and molecular levels. This research also involves field-based studies of plants under challenge at various sites throughout Victoria, Australia. The focus of this field-based research is to assess the responses of individual species to P. cinnamomi in the natural environment with the goal of identifying individuals within susceptible species that display \u27resistance\u27. Understanding how plants are able to resist this pathogen will enable strategies to be developed to enhance species survival and to restore structure and biodiversity to the ecosystems under threat.<br /

    Microwaves effectively examine the extent and type of coking over acid zeolite catalysts

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    Coking leads to the deactivation of solid acid catalyst. This phenomenon is a ubiquitous problem in the modern petrochemical and energy transformation industries. Here, we show a method based on microwave cavity perturbation analysis for an effective examination of both the amount and the chemical composition of cokes formed over acid zeolite catalysts. The employed microwave cavity can rapidly and non-intrusively measure the catalytically coked zeolites with sample full body penetration. The overall coke amount is reflected by the obtained dielectric loss (ε″) value, where different coke compositions lead to dramatically different absorption efficiencies (ε″/cokes’ wt%). The deeper-dehydrogenated coke compounds (e.g., polyaromatics) lead to an apparently higher ε″/wt% value thus can be effectively separated from lightly coked compounds. The measurement is based on the nature of coke formation during catalytic reactions, from saturated status (e.g., aliphatic) to graphitized status (e.g., polyaromatics), with more delocalized electrons obtained for enhanced Maxwell–Wagner polarization

    Wax: A benign hydrogen-storage material that rapidly releases H2-rich gases through microwave-assisted catalytic decomposition

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    Hydrogen is often described as the fuel of the future, especially for application in hydrogen powered fuel-cell vehicles (HFCV’s). However, its widespread implementation in this role has been thwarted by the lack of a lightweight, safe, on-board hydrogen storage material. Here we show that benign, readily-available hydrocarbon wax is capable of rapidly releasing large amounts of hydrogen through microwave-assisted catalytic decomposition. This discovery offers a new material and system for safe and efficient hydrogen storage and could facilitate its application in a HFCV. Importantly, hydrogen storage materials made of wax can be manufactured through completely sustainable processes utilizing biomass or other renewable feedstocks

    The plight of the sense-making ape

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    This is a selective review of the published literature on object-choice tasks, where participants use directional cues to find hidden objects. This literature comprises the efforts of researchers to make sense of the sense-making capacities of our nearest living relatives. This chapter is written to highlight some nonsensical conclusions that frequently emerge from this research. The data suggest that when apes are given approximately the same sense-making opportunities as we provide our children, then they will easily make sense of our social signals. The ubiquity of nonsensical contemporary scientific claims to the effect that humans are essentially--or inherently--more capable than other great apes in the understanding of simple directional cues is, itself, a testament to the power of preconceived ideas on human perception

    Towards sustainable processing of columbite group minerals: elucidating the relation between dielectric properties and physico-chemical transformations in the mineral phase

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    Current methodologies for the extraction of tantalum and niobium pose a serious threat to human beings and the environment due to the use of hydrofluoric acid (HF). Niobium and tantalum metal powders and pentoxides are widely used for energy efficient devices and components. However, the current processing methods for niobium and tantalum metals and oxides are energy inefficient. This dichotomy between materials use for energy applications and their inefficient processing is the main motivation for exploring a new methodology for the extraction of these two oxides, investigating the microwave absorption properties of the reaction products formed during the alkali roasting of niobium-tantalum bearing minerals with sodium bicarbonate. The experimental findings from dielectric measurement at elevated temperatures demonstrate an exponential increase in the values of the dielectric properties as a result of the formation of NaNbO3-NaTaO3solid solutions at temperatures above 700 °C. The investigation of the evolution of the dielectric properties during the roasting reaction is a key feature in underpinning the mechanism for designing a new microwave assisted high-temperature process for the selective separation of niobium and tantalum oxides from the remainder mineral crystalline lattice
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