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This article examines the ways in which the Fijian authors Vanessa Griffen, Pio Manoa, and Subramani revised and reworked modernist texts in their construction of a local postcolonial literature. These writers were schooled in a colonial education system that was, by the 1950s and 60s, in ideological disarray, as the jingoistic, imperial texts of the English syllabus began to give way to the crisis and self-interrogation of literary modernism. The students who graduated from these classes went on to create a first wave of Fijian creative writing in English. As this article shows, Griffen, Manoa, and Subramani carried into their writing fragments and forms of the texts they had been required to learn by rote, and they refashioned these into new wholes. In their short stories and poems of the late 1960s and early 70s, these writers turned the literature of past imperial breakdown towards present and future needs, adapting fragmentary, perspectival and multivocal texts towards a postcolonial independence still riven by colonially introduced problems. Ultimately, we argue, the creation of this new literature denotes the failure of the education system to impress British superiority upon its colonial subjects, and the success of the subaltern in reclaiming the means of expression.

Our study aimed to identify the broad effects of native fossorial species on leaf litter, and make inferences about their mechanistic influence on fire behavior using simulation models (Hayward et al., 2016). This conceptual link has long been hypothesized, but here we present empirical evidence to support it; our results suggest that native fossorial mammals have fire-suppressive effects because their activity results in higher levels of litter decomposition, and a reduced fuel load across the landscape. The expert commentaries build on this study and raise pertinent points for further consideration. Both Johnson (2016) and Watson (2016) expand on the interplay between the spatial distribution of fuel loads and fire dynamics. At the finest scale, spatial heterogeneity is achieved when animals scatter soil around localized diggings or turn over organic material into the soil profile. These localized events will aggregate into larger scale, landscape effects, where burrows and diggings occur in discriminate patches across the environment. Watson (2016) points out that these patches of decreased fuel would provide more substantial impediments to fire in the landscape by acting as natural fire breaks. We indirectly measured aspects of spatial heterogeneity, but to incorporate this variable accurately into future predictions, we suggest the following actions: (1) the activity of animals (burrows and diggings) be spatially mapped with GIS software to identify concentrations in the landscape and define natural fire breaks, (2) the relationship between litter heterogeneity and fire in the field be studied directly, either through experimental burns or surveys prior to natural burns, and (3) the input of more detailed data into fire models with finer resolution (as Johnson (2016) suggests). The explicit relationship between litter and fire lies at the core of this concept and thus warrants more accurate demonstration. Additionally, we acknowledge the points raised by Watson (2016) regarding population densities and the influence of floristic components on fire dynamics. As with most ecological studies concerning landscape processes, the complexities of all intra- and inter-species interactions in the system are rarely captured simultaneously (but should be considered) and this study worked within specific logistical constraints. Due to these constraints, our study could only document the influence of a subset of all fossorial mammals that were historically present in these areas. Further to this, we cannot accurately know whether experimental versus historical densities were equivalent. Thus, we do not know precisely how fire behavior would be influenced by a full assemblage of fossorial species (in realistic densities), or for that matter, a much wider variety of species that were present historically. We cannot rectify the issue of assemblages (some species are extinct) but clarifying the relationship between population density and magnitude of fire suppression would be a very useful line of future research. Understanding how feedback mechanisms between ecosystem engineers and fire play out in the field would also be very insightful, but would require studies over the longer term. Our experimental plots were large predator-free enclosures, containing populations of fossorial species. Watson (2016) suggests that conservation enclosures may be too rare and small to influence landscape processes at any meaningful scale; however, it is worth pointing out that they are becoming more common in Australia (Long & Robley, 2004). Not including the 3,374 km dingo-proof fence, Dickman (2012) listed 33 of these enclosures across Australia at the time, and we are aware of another two major enclosures that have been constructed since then (by the Northern Territory state government and by the Australian Wildlife Conservancy). Furthermore, most of these enclosures protect areas of high conservation value and represent the only places in which these faunal assemblages can be rigorously studied. These areas serve as arks for some of the most endangered critical weight-range mammals on mainland Australia, but perhaps their most important role in the context of conservation is to facilitate research. These experimental plots enable us to empirically test theories of ecosystem functionality (such as the one presented here) with a subset of fauna that has been largely incomplete since pre-colonial times. Such experimental manipulations present an opportunity for unique insights into the evolutionary underpinnings of ecosystem functionality in Australia. Most importantly, results from these studies provide justification for breeding programs and reintroductions of native mammals (teamed with enhanced suppression of invasive predators). Ideally, future conservation strategies would be designed in a more holistic manner, incorporating diversity and function. We concur with Petrosillo & Zurlini's (2016) assertion that the target of species reintroductions should become their ecological role in the context of system stability. However, we do not believe that our current knowledge is sufficient to confidently predict all such driving species in all circumstances; thus, we would add that restoring only species for whom ecological function is known would be an opportunity missed. Following the precautionary principle, we would advocate the restoration of as many species as possible. Restoring long-lost faunal assemblages to Australian ecosystems is no easy feat, but evidence is mounting globally which demonstrates the benefits of ecosystem management based strategically on ecological functionality. We cannot turn back the clock on faunal declines, but we can attempt to understand the historical importance of these faunal assemblages and why they warrant attention and preservation, now. All the expert commentaries speculate that (due to unavoidable constraints) our study likely underestimates the extent to which fossorial ecosystem engineers influence fire dynamics; we agree. More work is required to elucidate the roles that these species have played in the past and can play in the future of Australian ecosystems, but we believe our study provides a valuable contribution to this field and a good basis for future research.

Abstract. Volcanogenic tsunami and wave hazard remains less understood than that of other tsunami sources. Volcanoes can generate waves in a multitude of ways, including subaqueous explosions.
Recent events, including a highly explosive eruption at Hunga Tonga-Hunga Ha'apai and subsequent tsunami in January 2022, have reinforced the necessity to explore and quantify volcanic tsunami sources.
We utilise a non-hydrostatic multilayer numerical method to simulate 20 scenarios of sublacustrine explosive eruptions under Lake Taupō, New Zealand, across five locations and four eruption sizes.
Waves propagate around the entire lake within 15 min, and there is a minimum explosive size required to generate significant waves (positive amplitudes incident on foreshore of > 1 m) from the impulsive displacement of water from the eruption itself. This minimum size corresponds to a mass eruption rate of 5.8×107 kg s−1, or VEI 5 equivalent.
Inundation is mapped across five built areas and becomes significant near shore when considering only the two largest sizes, above VEI 5, which preferentially impact areas of low-gradient slope.
In addition, novel hydrographic output is produced showing the impact of incident waves on the Waikato River inlet draining the lake and is potentially useful for future structural impact analysis.
Waves generated from these explosive source types are highly dispersive, resulting in hazard rapidly diminishing with distance from the source.
With improved computational efficiency, a probabilistic study could be formulated and other, potentially more significant, volcanic source mechanisms should be investigated.

Abstract. Theoretical source models of underwater explosions are often applied in studying tsunami hazards associated with subaqueous volcanism; however, their use in numerical codes based on the shallow water equations can neglect the significant dispersion of the generated wavefield. A non-hydrostatic multilayer method is validated against a laboratory-scale experiment of wave generation from instantaneous disturbances and at field-scale subaqueous explosions at Mono Lake, California, utilising the relevant theoretical models. The numerical method accurately reproduces the range of observed wave characteristics for positive disturbances and suggests a relationship of extended initial troughs for negative disturbances at low-dispersivity and high-non-linearity parameters. Satisfactory amplitudes and phase velocities within the initial wave group are found using underwater explosion models at Mono Lake. The scheme is then applied to modelling tsunamis generated by volcanic explosions at Lake Taupō, New Zealand, for a magnitude representing an ejecta volume of 0.1 km3. Waves reach all shores within 15 min with maximum incident crest amplitudes around 0.2 m at shores near the source. This work shows that the multilayer scheme used is computationally efficient and able to capture a wide range of wave characteristics, including dispersive effects, which is necessary when investigating subaqueous explosions. This research therefore provides the foundation for future studies involving a rigorous probabilistic hazard assessment to quantify the risks and relative significance of this tsunami source mechanism.

Conservation actions, such as habitat protection, attempt to halt the loss of threatened species and help their populations to recover. Various research has examined the efficiency and the effectiveness of actions individually. However, conservation actions generally occur simultaneously so the full suite of implemented conservation actions should be assessed. We used the conservation actions underway for all threatened and near-threatened birds of the world (IUCN Red List of Threatened Species) to assess which biological (related to taxonomy and ecology) and anthropogenic (related to geo-economics) factors are associated with the implementation of different classes of conservation actions. We also assessed which conservation actions are associated with population increases in the species targeted. Extinction risk category was the strongest single predictor of the type of conservation actions implemented, followed by landmass type (continent, oceanic island etc) and generation length. Species targeted by invasive alien species control/eradication programs, ex situ conservation, international legislation, reintroduction, or education and awareness-raising activities were more likely to have increasing populations. These results illustrate the importance of developing a predictive science of conservation actions and the relative benefits of each class of implemented conservation action for threatened and near-threatened birds worldwide.

From the late Pleistocene to the Holocene and now the so-called Anthropocene, humans have been driving an ongoing series of species declines and extinctions (Dirzo et al. 2014). Large-bodied mammals are typically at a higher risk of extinction than smaller ones (Cardillo et al. 2005). However, in some circumstances, terrestrial megafauna populations have been able to recover some of their lost numbers because of strong conservation and political commitment, as well as human cultural changes (Chapron et al. 2014). Indeed, many would be in considerably worse predicaments in the absence of conservation action (Hoffmann et al. 2015). Nevertheless, most mammalian megafauna face dramatic range contractions and population declines. In fact, 59% of the world's largest carnivores (more than or equal to 15 kilograms, n = 27) and 60% of the world's largest herbivores (more than or equal to 100 kilograms, n = 74) are classified as threatened with extinction on the International Union for the Conservation of Nature (IUCN) Red List (supplemental tables S1 and S2). This situation is particularly dire in sub-Saharan Africa and Southeast Asia, home to the greatest diversity of extant megafauna (figure 1). Species at risk of extinction include some of the world's most iconic animals—such as gorillas, rhinos, and big cats (figure 2 top row)—and, unfortunately, they are vanishing just as science is discovering their essential ecological roles (Estes et al. 2011). Here, our objectives are to raise awareness of how these megafauna are imperiled (species in tables S1 and S2) and to stimulate broad interest in developing specific recommendations and concerted action to conserve them.