77 resultados para human impact

em Deakin Research Online - Australia


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In the light of the currently increasing drought frequency and water scarcity on oceanic islands, it is crucial for the conservation of threatened insular vertebrates to assess how they will be affected. A 4000 yr old fossil assemblage in the Mare Aux Songes (MAS), southwest Mauritius, Mascarene Islands, contains bones of 100 000+ individual vertebrates, dominated by two species of giant tortoises Cylindraspis triserrata and C. inepta, the dodo Raphus cucullatus, and 20 other vertebrate species (Rijsdijk, Hume, Bunnik, Florens, Baider, Shapiro et al. (2009) Mid-Holocene vertebrate bone Concentration-Lagerstätte on oceanic island Mauritius provides a window into the ecosystem of the dodo (Raphus cucullatus). Quaternary Science Reviews 28: 14–24). Nine radiocarbon dates of bones statistically overlap and suggest mass mortality occurred between 4235 and 4100 cal. yr BP. The mortality period coincides with a widely recognized megadrought event. Our multidisciplinary investigations combining geological, paleontological and hydrological evidence suggests the lake was located in a dry coastal setting and had desiccated during this period. Oxygen isotope data from a Uranium-series dated stalagmite from Rodrigues, an island 560 km east of Mauritius, supports this scenario by showing frequently alternating dry and wet periods lasting for decades between 4122 and 2260 cal. yr BP. An extreme drought resulted in falling water-tables at MAS and elsewhere on the island, perhaps deprived these insular vertebrates of fresh water, which led to natural mass mortalities and possibly to extirpations. In spite of these events, all insular species survived until at least the seventeenth century, confirming their resistance to climatic extremes. Despite this, the generally exponential increase of combined human impacts on islands including loss of geodiversity, habitats, and stocks of fresh water, there will be less environmental safe-haven options for insular endemic and native vertebrates during future megadrought conditions; and therefore will be more prone to extinction.

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Before the turn of the century, few states used immigration detention. Today, nearly every state around the world has adopted immigration detention policy in some form. States practice detention as a means to address both the accelerating numbers of people crossing their borders, and the populations residing in their states without authorisation. This edited volume examines the contemporary diffusion of immigration detention policy throughout the world and the impact of this expansion on the prospects of protection for people seeking asylum. It includes contributions by immigration detention experts working in Australasia, the Americas, Europe, Africa and the Middle East. It is the first to set out a systematic comparison of immigration detention policy across these regions and to examine how immigration detention has become a ubiquitous part of border and immigration control strategies globally. In so doing, the volume presents a global perspective on the diversity of immigration detention policies and practices, how these circumstances developed, and the human impact of states exchanging individuals' rights to liberty for the collective assurance of border and immigration control. This text will be of key interest to scholars, students and practitioners of immigration, migration, public administration, comparative policy studies, comparative politics and international political economy.

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Biological invasions are acknowledged among the main drivers of global changes in biodiversity. Despite compelling evidence of species interactions being strongly regulated by environmental conditions, there is a dearth of studies investi-gating how the effects of non-native species vary among areas exposed to different anthropogenic pressures. Focusing on marine macroalgae, we performed a meta-analysis to test whether and how the direction and magnitude of their effects on resident communities and species varies in relation to cumulative anthropogenic impact levels. The relationship between human impact levels and non-native species impact intensity emerged only for a reduced subset of the response variables examined. Yet, there was a trend for the effects of non-native species on community biomass and abundance and on species abundance to become less negative at heavily impacted sites. By contrast, the magnitude of negative effects of seaweed on community evenness tended to increase with human impact levels. The hypothesis of decreasing severity of invader’ impacts along a gradient of habitat degradation was also tested experimentally at a regional scale by comparing the effects of the removal of non-native alga,
Caulerpa cylindracea, on resident assemblages among rocky reefs exposed to different anthropogenic pressures. Assemblages at urban and pristine site did not differ when invaded, but did so when C. cylindracea was removed. Our results suggest that, despite the generally weak relationship between human impacts levels and non-native species impacts, more negative impacts can be expected in less stressful environments (i.e. less degraded or pristine sites), where competitive interactions are presumably the driving force structuring resident communities. Implementing strategies for controlling the establishment of non-native seaweeds should be, thus, considered a priority for preserving biodiversity in relatively pristine areas. On the other hand, control of invaders at degraded sites could be warranted to lessen their role as propagule sources

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All asylum seekers who arrive in Australia’s territorial waters by boat are subject to mandatory, indefinite and unreviewable detention on Nauru and Papua New Guinea. This offshore detention regime is characterised by a high degree of secrecy, low levels of transparency and accountability, and few opportunities for external oversight. This has created a closed, controlled environment, in which people are routinely neglected and harmed. To better understand the human impact of Australia’s offshore detention regime, this article draws on research from social psychology regarding human behaviour in closed institutions. This research – which has substantially informed prison policies throughout the Western world – demonstrates the critical importance of external oversight, openness and transparency for the protection of human rights of people in closed institutions. This knowledge has not been applied to Australia’s offshore immigration detention regime. To the contrary: creating a closed, opaque system of detention has been an explicit policy goal of the Australian government. By actively restricting transparency, this research demonstrates that not only are the abuses of detainees’ human rights hidden from the public eye, they are inevitable.

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Although the recent history of human colonisation and impact on Mauritius is well documented, virtually no records of the pre-human native ecosystem exist, making it difficult to assess the magnitude of the changes brought about by human settlement. Here, we describe a 4000-year-old fossil bed at Mare aux Songes (MAS) in south-eastern Mauritius that contains both macrofossils (vertebrate fauna, gastropods, insects and flora) and microfossils (diatoms, pollen, spores and phytoliths). With >250 bone fragments/m2 and comprising 50% of all known extinct and extant vertebrate species (ns = 44) of Mauritius, MAS may constitute the first Holocene vertebrate bone Concentration-Lagerstätte identified on an oceanic volcanic island. Fossil remains are dominated by extinct giant tortoises Cylindraspis spp. (63%), passerines (10%), small bats (7.8%) and dodo Raphus cucullatus (7.1%). Twelve radiocarbon ages [four of them duplicates] from bones and other material suggest that accumulation of fossils took place within several centuries. An exceptional combination of abiotic conditions led to preservation of bones, bone collagen, plant tissue and microfossils. Although bone collagen is well preserved, DNA from dodo and other Mauritian vertebrates has proved difficult. Our analysis suggests that from ca 4000 years ago (4 ka), rising sea levels created a freshwater lake at MAS, generating an oasis in an otherwise dry environment which attracted a diverse vertebrate fauna. Subsequent aridification in the south-west Indian Ocean region may have increased carcass accumulation during droughts, contributing to the exceptionally high fossil concentration. The abundance of floral and faunal remains in this Lagerstätte offers a unique opportunity to reconstruct a pre-human ecosystem on an oceanic island, providing a key foundation for assessing the vulnerability of island ecosystems to human impact.

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 This chapter outlines the policy, practice, and human impact of immigration detention in Indonesia. An important part of the Indonesian immigration detention story is the role of Australia, and this chapter explains how Australian diplomacy, human resources, and funding have been central to the development of Indonesia's immigration detention network.

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As a discipline, marine historical ecology (MHE) has contributed significantly to our understanding of the past state of the marine environment when levels of human impact were often very different from those today.What is less widely known is that insights from MHE have made headway into being applied within the context of present-day and long-term management and policy. This study draws attention to the applied value of MHE. We demonstrate that a broad knowledge base exists with potential for management application and advice, including the development of baselines and reference levels.Using a number of case studies from around the world,we showcase the value of historical ecology in understanding change and emphasize how it either has already informed management or has the potential to do so soon.We discuss these case studies in a context of the science–policy interface around six themes that are frequently targeted by current marine and maritime policies: climate change, biodiversity conservation, ecosystem structure, habitat integrity, food security, and human governance.We encourage science–policy bodies to actively engage with contributions from MHE, as well informed policy decisions need to be framed within the context of historical reference points and past resource or ecosystem changes.

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The unanticipated rise of religious diversity and the re-entry of religion to the public sphere have radically increased the need and demand for education about religions – how they contribute to social and cultural capital – and about the management of religious diversity. The global movement of people and cultures has brought religious diversity to nearly every major city. With diversity has come a renewed interest in the religious identity of others and how to incorporate religious diversity in ways that produce social cohesion. Religious diversity has also raised interest in a values discourse where once atheistic secularity prevailed, made faith-based social and health service delivery both more appealing to governments and more difficult to deliver, and has challenged societies to accommodate a wider range of religious needs and lifestyles. Policies designed to promote social justice and peace have little chance of success without taking seriously the religious dimensions to the issues involved. This context makes clear the need for opportunities to learn about the religions in a society at all levels of education – opportunities that include direct experience of the ‘other’, curricula that appreciate the worlds of faith, spirituality and religion rather than demeaning them, education that provides both historical depth and local reality. Some of this education will be in school, some in remedial work required for a generation or two of leaders who have been raised in ignorance of religion, or trained to despise it.

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Some may argue that the introduction of the Human Rights Act 1998 (HRA) has benefited only celebrities and asylum-seekers. Others contend that the HRA is a significant piece of legislation that has the potential to promote and protect the rights of the most vulnerable in our society. A few years after the Act's introduction this contribution considers the impact it has had on mental health practice in the UK.