210 resultados para alien species

em Queensland University of Technology - ePrints Archive


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The spatiotemporal dynamics of an alien species invasion across a real landscape are typically complex. While surveillance is an essential part of a management response, planning surveillance in space and time present a difficult challenge due to this complexity. We show here a method for determining the highest probability sites for occupancy across a landscape at an arbitrary point in the future, based on occupancy data from a single slice in time. We apply to the method to the invasion of Giant Hogweed, a serious weed in the Czech republic and throughout Europe.

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1. The ability of many introduced fish species to thrive in degraded aquatic habitats and their potential to impact on aquatic ecosystem structure and function suggest that introduced fish may represent both a symptom and a cause of decline in river health and the integrity of native aquatic communities. 2. The varying sensitivities of many commonly introduced fish species to degraded stream conditions, the mechanism and reason for their introduction and the differential susceptibility of local stream habitats to invasion because of the environmental and biological characteristics of the receiving water body, are all confounding factors that may obscure the interpretation of patterns of introduced fish species distribution and abundance and therefore their reliability as indicators of river health. 3. In the present study, we address the question of whether alien fish (i.e. those species introduced from other countries) are a reliable indicator of the health of streams and rivers in south-eastern Queensland, Australia. We examine the relationships of alien fish species distributions and indices of abundance and biomass with the natural environmental features, the biotic characteristics of the local native fish assemblages and indicators of anthropogenic disturbance at a large number of sites subject to varying sources and intensities of human impact. 4. Alien fish species were found to be widespread and often abundant in south-eastern Queensland rivers and streams, and the five species collected were considered to be relatively tolerant to river degradation, making them good candidate indicators of river health. Variation in alien species indices was unrelated to the size of the study sites, the sampling effort expended or natural environmental gradients. The biological resistance of the native fish fauna was not concluded to be an important factor mediating invasion success by alien species. Variation in alien fish indices was, however, strongly related to indicators of disturbance intensity describing local in-stream habitat and riparian degradation, water quality and surrounding land use, particularly the amount of urban development in the catchment. 5. Potential confounding factors that may influence the likelihood of introduction and successful establishment of an alien species and the implications of these factors for river bioassessment are discussed. We conclude that the potentially strong impact that many alien fish species can have on the biological integrity of natural aquatic ecosystems, together with their potential to be used as an initial basis to find out other forms of human disturbance impacts, suggest that some alien species (particularly species from the family Poeciliidae) can represent a reliable 'first cut' indicator of river health.

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Intelligible and accurate risk-based decision-making requires a complex balance of information from different sources, appropriate statistical analysis of this information and consequent intelligent inference and decisions made on the basis of these analyses. Importantly, this requires an explicit acknowledgement of uncertainty in the inputs and outputs of the statistical model. The aim of this paper is to progress a discussion of these issues in the context of several motivating problems related to the wider scope of agricultural production. These problems include biosecurity surveillance design, pest incursion, environmental monitoring and import risk assessment. The information to be integrated includes observational and experimental data, remotely sensed data and expert information. We describe our efforts in addressing these problems using Bayesian models and Bayesian networks. These approaches provide a coherent and transparent framework for modelling complex systems, combining the different information sources, and allowing for uncertainty in inputs and outputs. While the theory underlying Bayesian modelling has a long and well established history, its application is only now becoming more possible for complex problems, due to increased availability of methodological and computational tools. Of course, there are still hurdles and constraints, which we also address through sharing our endeavours and experiences.

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By 1925, the introduced prickly pear (Opuntia and Nopalea spp.) covered up to 60 million acres of Queensland and New South Wales in what was perceived as prime agricultural land. After 40 years of experimentation, all Queensland Government strategies had failed. Faced with this failure and a diminishing expectation that the land would ever be conquered, buffer zones were proposed by the newly formed Queensland Prickly Pear Land Commission. A close reading of government documents, newspaper reports and local histories about these buffer zones shows how settler anxieties over who could or should occupy the land shaped the kinds of strategies recommended and adopted in relation to this alien species. Physical and cultural techniques were used to manage the uneasy coexistence between prickly pear, on the one hand, and farmers and graziers on the other. Furthermore, this environmental history challenges the notion of racially homogenous closer settlement under the White Australia Policy, showing the many different kinds of livelihood and labour in prickly pear land in the 1920s.

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There has been much controversy over the Trans-Pacific Partnership (TPP) – a plurilateral trade agreement involving a dozen nations from throughout the Pacific Rim – and its impact upon the environment, biodiversity, and climate change. The secretive treaty negotiations involve Australia and New Zealand; countries from South East Asia such as Brunei Darussalam, Malaysia, Singapore, Vietnam, and Japan; the South American nations of Peru and Chile; and the members of the 1994 North American Free Trade Agreement (NAFTA), Canada, Mexico and the United States. There was an agreement reached between the parties in October 2015. The participants asserted: ‘We expect this historic agreement to promote economic growth, support higher-paying jobs; enhance innovation, productivity and competitiveness; raise living standards; reduce poverty in our countries; and to promote transparency, good governance, and strong labor and environmental protections.’ The final texts of the agreement were published in November 2015. There has been discussion as to whether other countries – such as Indonesia, the Philippines, and South Korea – will join the deal. There has been much debate about the impact of this proposed treaty upon intellectual property, the environment, biodiversity and climate change. There have been similar concerns about the Trans-Atlantic Trade and Investment Partnership (TTIP) – a proposed trade agreement between the United States and the European Union. In 2011, the United States Trade Representative developed a Green Paper on trade, conservation, and the environment in the context of the TPP. In its rhetoric, the United States Trade Representative has maintained that it has been pushing for strong, enforceable environmental standards in the TPP. In a key statement in 2014, the United States Trade Representative Mike Froman insisted: ‘The United States’ position on the environment in the Trans-Pacific Partnership negotiations is this: environmental stewardship is a core American value, and we will insist on a robust, fully enforceable environment chapter in the TPP or we will not come to agreement.’ The United States Trade Representative maintained: ‘Our proposals in the TPP are centered around the enforcement of environmental laws, including those implementing multilateral environmental agreements (MEAs) in TPP partner countries, and also around trailblazing, first-ever conservation proposals that will raise standards across the region’. Moreover, the United States Trade Representative asserted: ‘Furthermore, our proposals would enhance international cooperation and create new opportunities for public participation in environmental governance and enforcement.’ The United States Trade Representative has provided this public outline of the Environment Chapter of the TPP: A meaningful outcome on environment will ensure that the agreement appropriately addresses important trade and environment challenges and enhances the mutual supportiveness of trade and environment. The Trans-Pacific Partnership countries share the view that the environment text should include effective provisions on trade-related issues that would help to reinforce environmental protection and are discussing an effective institutional arrangement to oversee implementation and a specific cooperation framework for addressing capacity building needs. They also are discussing proposals on new issues, such as marine fisheries and other conservation issues, biodiversity, invasive alien species, climate change, and environmental goods and services. Mark Linscott, an assistant Trade Representative testified: ‘An environment chapter in the TPP should strengthen country commitments to enforce their environmental laws and regulations, including in areas related to ocean and fisheries governance, through the effective enforcement obligation subject to dispute settlement.’ Inside US Trade has commented: ‘While not initially expected to be among the most difficult areas, the environment chapter has emerged as a formidable challenge, partly due to disagreement over the United States proposal to make environmental obligations binding under the TPP dispute settlement mechanism’. Joshua Meltzer from the Brookings Institute contended that the trade agreement could be a boon for the protection of the environment in the Pacific Rim: Whether it is depleting fisheries, declining biodiversity or reduced space in the atmosphere for Greenhouse Gas emissions, the underlying issue is resource scarcity. And in a world where an additional 3 billion people are expected to enter the middle class over the next 15 years, countries need to find new and creative ways to cooperate in order to satisfy the legitimate needs of their population for growth and opportunity while using resources in a manner that is sustainable for current and future generations. The TPP parties already represent a diverse range of developed and developing countries. Should the TPP become a free trade agreement of the Asia-Pacific region, it will include the main developed and developing countries and will be a strong basis for building a global consensus on these trade and environmental issues. The TPP has been promoted by its proponents as a boon to the environment. The United States Trade Representative has maintained that the TPP will protect the environment: ‘The United States’ position on the environment in the TPP negotiations is this: environmental stewardship is a core American value, and we will insist on a robust, fully enforceable environment chapter in the TPP or we will not come to agreement.’ The United States Trade Representative discussed ‘Trade for a Greener World’ on World Environment Day. Andrew Robb, at the time the Australian Trade and Investment Minister, vowed that the TPP will contain safeguards for the protection of the environment. In November 2015, after the release of the TPP text, Rohan Patel, the Special Assistant to the President and Deputy Director of Intergovernmental Affairs, sought to defend the environmental credentials of the TPP. He contended that the deal had been supported by the Nature Conservancy, the International Fund for Animal Welfare, the Joint Ocean Commission Initiative, the World Wildlife Fund, and World Animal Protection. The United States Congress, though, has been conflicted by the United States Trade Representative’s arguments about the TPP and the environment. In 2012, members of the United States Congress - including Senator Ron Wyden (D-OR), Olympia Snowe (R-ME), and John Kerry (D-MA) – wrote a letter, arguing that the trade agreement needs to provide strong protection for the environment: ‘We believe that a '21st century agreement' must have an environment chapter that guarantees ongoing sustainable trade and creates jobs, and this is what American businesses and consumers want and expect also.’ The group stressed that ‘A binding and enforceable TPP environment chapter that stands up for American interests is critical to our support of the TPP’. The Congressional leaders maintained: ‘We believe the 2007 bipartisan congressional consensus on environmental provisions included in recent trade agreements should serve as the framework for the environment chapter of the TPP.’ In 2013, senior members of the Democratic leadership expressed their opposition to granting President Barack Obama a fast-track authority in respect of the TPP House of Representatives Minority Leader Nancy Pelosi said: ‘No on fast-track – Camp-Baucus – out of the question.’ Senator Majority leader Harry Reid commented: ‘I’m against Fast-Track: Everyone would be well-advised to push this right now.’ Senator Elizabeth Warren has been particularly critical of the process and the substance of the negotiations in the TPP: From what I hear, Wall Street, pharmaceuticals, telecom, big polluters and outsourcers are all salivating at the chance to rig the deal in the upcoming trade talks. So the question is, Why are the trade talks secret? You’ll love this answer. Boy, the things you learn on Capitol Hill. I actually have had supporters of the deal say to me ‘They have to be secret, because if the American people knew what was actually in them, they would be opposed. Think about that. Real people, people whose jobs are at stake, small-business owners who don’t want to compete with overseas companies that dump their waste in rivers and hire workers for a dollar a day—those people, people without an army of lobbyists—they would be opposed. I believe if people across this country would be opposed to a particular trade agreement, then maybe that trade agreement should not happen. The Finance Committee in the United States Congress deliberated over the Trans-Pacific Partnership negotiations in 2014. The new chair Ron Wyden has argued that there needs to be greater transparency in trade. Nonetheless, he has mooted the possibility of a ‘smart-track’ to reconcile the competing demands of the Obama Administration, and United States Congress. Wyden insisted: ‘The new breed of trade challenges spawned over the last generation must be addressed in imaginative new policies and locked into enforceable, ambitious, job-generating trade agreements.’ He emphasized that such agreements ‘must reflect the need for a free and open Internet, strong labor rights and environmental protections.’ Elder Democrat Sander Levin warned that the TPP failed to provide proper protection for the environment: The TPP parties are considering a different structure to protect the environment than the one adopted in the May 10 Agreement, which directly incorporated seven multilateral environmental agreements into the text of past trade agreements. While the form is less important than the substance, the TPP must provide an overall level of environmental protection that upholds and builds upon the May 10 standard, including fully enforceable obligations. But many of our trading partners are actively seeking to weaken the text to the point of falling short of that standard, including on key issues like conservation. Nonetheless, 2015, President Barack Obama was able to secure the overall support of the United States Congress for his ‘fast-track’ authority. This was made possible by the Republicans and dissident Democrats. Notably, Oregon Senator Ron Wyden switched sides, and was transformed from a critic of the TPP to an apologist for the TPP. For their part, green political parties and civil society organisations have been concerned about the secretive nature of the negotiations; and the substantive implications of the treaty for the environment. Environmental groups and climate advocates have been sceptical of the environmental claims made by the White House for the TPP. The Green Party of Aotearoa New Zealand, the Australian Greens and the Green Party of Canada have released a joint declaration on the TPP observing: ‘More than just another trade agreement, the TPP provisions could hinder access to safe, affordable medicines, weaken local content rules for media, stifle high-tech innovation, and even restrict the ability of future governments to legislate for the good of public health and the environment’. In the United States, civil society groups such as the Sierra Club, Public Citizen, WWF, the Friends of the Earth, the Rainforest Action Network and 350.org have raised concerns about the TPP and the environment. Allison Chin, President of the Sierra Club, complained about the lack of transparency, due process, and public participation in the TPP talks: ‘This is a stealth affront to the principles of our democracy.’ Maude Barlow’s The Council of Canadians has also been concerned about the TPP and environmental justice. New Zealand Sustainability Council executive director Simon Terry said the agreement showed ‘minimal real gains for nature’. A number of organisations have joined a grand coalition of civil society organisations, which are opposed to the grant of a fast-track. On the 15th January 2013, WikiLeaks released the draft Environment Chapter of the TPP - along with a report by the Chairs of the Environmental Working Group. Julian Assange, WikiLeaks' publisher, stated: ‘Today's WikiLeaks release shows that the public sweetener in the TPP is just media sugar water.’ He observed: ‘The fabled TPP environmental chapter turns out to be a toothless public relations exercise with no enforcement mechanism.’ This article provides a critical examination of the draft Environment Chapter of the TPP. The overall argument of the article is that the Environment Chapter of the TPP is an exercise in greenwashing – it is a public relations exercise by the United States Trade Representative, rather than a substantive regime for the protection of the environment in the Pacific Rim. Greenwashing has long been a problem in commerce, in which companies making misleading and deceptive claims about the environment. In his 2012 book, Greenwash: Big Brands and Carbon Scams, Guy Pearse considers the rise of green marketing and greenwashing. Government greenwashing is also a significant issue. In his book Storms of My Grandchildren, the climate scientist James Hansen raises his concerns about government greenwashing. Such a problem is apparent with the TPP – in which there was a gap between the assertions of the United States Government, and the reality of the agreement. This article contends that the TPP fails to meet the expectations created by President Barack Obama, the White House, and the United States Trade Representative about the environmental value of the agreement. First, this piece considers the relationship of the TPP to multilateral environmental treaties. Second, it explores whether the provisions in respect of the environment are enforceable. Third, this article examines the treatment of trade and biodiversity in the TPP. Fourth, this study considers the question of marine capture fisheries. Fifth, there is an evaluation of the cursory text in the TPP on conservation. Sixth, the article considers trade in environmental services under the TPP. Seventh, this article highlights the tensions between the TPP and substantive international climate action. It is submitted that the TPP undermines effective and meaningful government action and regulation in respect of climate change. The conclusion also highlights that a number of other chapters of the TPP will impact upon the protection of the environment – including the Investment Chapter, the Intellectual Property Chapter, the Technical Barriers to Trade Chapter, and the text on public procurement.

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Complex surveillance problems are common in biosecurity, such as prioritizing detection among multiple invasive species, specifying risk over a heterogeneous landscape, combining multiple sources of surveillance data, designing for specified power to detect, resource management, and collateral effects on the environment. Moreover, when designing for multiple target species, inherent biological differences among species result in different ecological models underpinning the individual surveillance systems for each. Species are likely to have different habitat requirements, different introduction mechanisms and locations, require different methods of detection, have different levels of detectability, and vary in rates of movement and spread. Often there is a further challenge of a lack of knowledge, literature, or data, for any number of the above problems. Even so, governments and industry need to proceed with surveillance programs which aim to detect incursions in order to meet environmental, social and political requirements. We present an approach taken to meet these challenges in one comprehensive and statistically powerful surveillance design for non-indigenous terrestrial vertebrates on Barrow Island, a high conservation nature reserve off the Western Australian coast. Here, the possibility of incursions is increased due to construction and expanding industry on the island. The design, which includes mammals, amphibians and reptiles, provides a complete surveillance program for most potential terrestrial vertebrate invaders. Individual surveillance systems were developed for various potential invaders, and then integrated into an overall surveillance system which meets the above challenges using a statistical model and expert elicitation. We discuss the ecological basis for the design, the flexibility of the surveillance scheme, how it meets the above challenges, design limitations, and how it can be updated as data are collected as a basis for adaptive management.

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Introduction Novel ecosystems that contain new combinations of invasive alien plants (IAPs) present a challenge for managers. Yet, control strategies that focus on the removal of the invasive species and/or restoring historical disturbance regimes often do not provide the best outcome for long-term control of IAPs and the promotion of more desirable plant species. Methods This study seeks to identify the primary drivers of grassland invasion to then inform management practices toward the restoration of native ecosystems. By revisiting both published and unpublished data from experiments and case studies within mainly an Australian context for native grassland management, we show how alternative states models can help to design control strategies to manage undesirable IAPs by manipulating grazing pressure. Results Ungulate grazing is generally considered antithetical to invasive species management because in many countries where livestock production is a relatively new disturbance to grasslands (such as in Australia and New Zealand as well as Canada and the USA), selective grazing pressure may have facilitated opportunities for IAPs to establish. We find that grazing stock can be used to manipulate species composition in favour of the desirable components in pastures, but whether grazing is rested or strategically applied depends on the management goal, sizes of populations of the IAP and more desirable species, and climatic and edaphic conditions. Conclusions Based on our findings, we integrated these relationships to develop a testable framework for managing IAPs with strategic grazing that considers both the current state of the plant community and the desired future state—i.e. the application of the principles behind reclamation, rehabilitation, restoration or all three—over time.

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This paper examines empirically the relative influence of the degree of endangerment of wildlife species and their stated likeability on individuals' allocation of funds for their conservation. To do this, it utilises data obtained from the IUCN Red List, and likeability and fund allocation data obtained from two serial surveys of a sample of the Australian public who were requested to assess 24 Australian wildlife species from three animal classes: mammals, birds and reptiles. Between the first and second survey, respondents were provided with extra information about the focal species. This information resulted in the dominance of endangerment as the major influence on the allocation of funding of respondents for the conservation of the focal wildlife species. Our results throw doubts on the proposition in the literature that the likeability of species is the dominant influence on willingness to pay for conservation of wildlife species. Furthermore, because the public's allocation of fund for conserving wildlife species seems to be more sensitive to information about the conservation status of species than to factors influencing their likeability, greater attention to providing accurate information about the former than the latter seems justified. Keywords: Conservation of wildlife species; Contingent valuation; Endangerment of species; Likeability of species; Willingness to pay