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1.
Gigascience ; 132024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38442145

RESUMEN

BACKGROUND: Spatial information about the location and suitability of areas for native plant and animal species under different climate futures is an important input to land use and conservation planning and management. Australia, renowned for its abundant species diversity and endemism, often relies on modeled data to assess species distributions due to the country's vast size and the challenges associated with conducting on-ground surveys on such a large scale. The objective of this article is to develop habitat suitability maps for Australian flora and fauna under different climate futures. RESULTS: Using MaxEnt, we produced Australia-wide habitat suitability maps under RCP2.6-SSP1, RCP4.5-SSP2, RCP7.0-SSP3, and RCP8.5-SSP5 climate futures for 1,382 terrestrial vertebrates and 9,251 vascular plants vascular plants at 5 km2 for open access. This represents 60% of all Australian mammal species, 77% of amphibian species, 50% of reptile species, 71% of bird species, and 44% of vascular plant species. We also include tabular data, which include summaries of total quality-weighted habitat area of species under different climate scenarios and time periods. CONCLUSIONS: The spatial data supplied can help identify important and sensitive locations for species under various climate futures. Additionally, the supplied tabular data can provide insights into the impacts of climate change on biodiversity in Australia. These habitat suitability maps can be used as input data for landscape and conservation planning or species management, particularly under different climate change scenarios in Australia.


Asunto(s)
Biodiversidad , Mamíferos , Animales , Australia
2.
Glob Chang Biol ; 27(12): 2744-2762, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33759299

RESUMEN

Biological sources of carbon sequestration such as revegetation have been highlighted as important avenues to combat climate change and meet global targets by the global community including the Paris Climate Agreement. However, current and projected carbon prices present a considerable barrier to broad-scale adoption of tree planting as a key mitigation strategy. One avenue to provide additional economic and environmental incentives to encourage wider adoption of revegetation is the bundling or stacking of additional co-beneficial ecosystem services that can be realized from tree planting. Using the World's largest land-based carbon credit trading scheme, the Australian Emissions Reduction Scheme (ERF), we examine the potential for three pairs of ecosystem services, where the carbon sequestration value of land use change is paired with an additional co-benefit with strong prospects for local tangible benefits to land owners/providers. Two cases consider agricultural provisioning values that can be realized by the landowners in higher returns: increased pollination services and reduced lamb mortality. The third case examined payments for tree plantings along riparian buffers, with payments to farmers by a water utility who realizes the benefit from reduced treatment cost due to water quality improvements. Economic incentives from these co-benefit case studies were found to be mixed, with avoided treatment costs from water quality paired with carbon payments the most promising, while pollination and reduced lamb mortality paired with carbon payments were unable to bridge the economic gap except under the most optimistic assumptions. We conclude that the economics case for significant land use change are likely to be geographically dispersed and only viable in relatively niche landscape positions in high establishment, high opportunity cost areas even when carbon payments are augmented with the value of co-benefits classified as providing direct and local benefits.


Asunto(s)
Carbono , Ecosistema , Animales , Australia , Carbono/análisis , Secuestro de Carbono , Conservación de los Recursos Naturales , Ovinos
3.
Sustain Sci ; 11(5): 733-747, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-30174741

RESUMEN

Changing unsustainable natural resource use in agricultural landscapes is a complex social-ecological challenge that cannot be addressed through traditional reductionist science. More holistic and inclusive (or transdisciplinary) processes are needed. This paper describes a transdisciplinary project for natural resource management planning in two regions (Eyre Peninsula and South Australian Murray-Darling Basin) of southern Australia. With regional staff, we reviewed previous planning to gain an understanding of the processes used and to identify possible improvement in plan development and its operation. We then used an envisioning process to develop a value-rich narrative of regional aspirations to assist stakeholder engagement and inform the development of a land use management option assessment tool called the landscape futures analysis tool (LFAT). Finally, we undertook an assessment of the effectiveness of the process through semi-structured stakeholder interviews. The planning process review highlighted the opinion that the regional plans were not well informed by available science, that they lacked flexibility, and were only intermittently used after publication. The envisioning process identified shared values-generally described as a trust, language that is easily understood, wise use of resources, collaboration and inclusiveness. LFAT was designed to bring the best available science together in a form that would have use in planning, during community consultation and in assessing regional management operations. The LFAT provided spatially detailed but simple models of agricultural yields and incomes, plant biodiversity, weed distribution, and carbon sequestration associated with future combinations of climate, commodity and carbon prices, and costs of production. Stakeholders were impressed by the presentation and demonstration results of the software. While there was anecdotal evidence that the project provided learning opportunities and increased understanding of potential land use change associated with management options under global change, the direct evidence of influence in the updated regional plan was limited. This project had elements required for success in transdisciplinary research, but penetration seems limited. Contributing factors appear to be a complexity of climate effects with economic uncertainty, lack of having the project embedded in the plan revision process, limited continuity and capacity of end users and limited after project support and promotion. Strategies are required to minimise the controlling influence that these limitations can have.

4.
Conserv Biol ; 25(4): 835-45, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21507060

RESUMEN

A price on carbon is expected to generate demand for carbon offset schemes. This demand could drive investment in tree-based monocultures that provide higher carbon yields than diverse plantings of native tree and shrub species, which sequester less carbon but provide greater variation in vegetation structure and composition. Economic instruments such as species conservation banking, the creation and trading of credits that represent biological-diversity values on private land, could close the financial gap between monocultures and more diverse plantings by providing payments to individuals who plant diverse species in locations that contribute to conservation and restoration goals. We studied a highly modified agricultural system in southern Australia that is typical of many temperate agriculture zones globally (i.e., has a high proportion of endangered species, high levels of habitat fragmentation, and presence of non-native species). We quantified the economic returns from agriculture and from carbon plantings (monoculture and mixed tree and shrubs) under six carbon-price scenarios. We also identified high-priority locations for restoration of cleared landscapes with mixed tree and shrub carbon plantings. Depending on the price of carbon, direct annual payments to landowners of AU$7/ha/year to $125/ha/year (US$6-120/ha/year) may be sufficient to augment economic returns from a carbon market and encourage tree plantings that contribute more to the restoration of natural systems and endangered species habitats than monocultures. Thus, areas of high priority for conservation and restoration may be restored relatively cheaply in the presence of a carbon market. Overall, however, less carbon is sequestered by mixed native tree and shrub plantings.


Asunto(s)
Carbono , Conservación de los Recursos Naturales/economía , Australia , Ecosistema
5.
J Clin Rheumatol ; 16(5): 225-8, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20661069

RESUMEN

It is not established whether the increased risk of stroke in patients with giant cell arteritis (GCA) is because of atherosclerosis, persistent arterial inflammation, or an iatrogenic effect of corticosteroids. This creates difficulties in choosing the most appropriate treatment. We report 2 patients with GCA who developed repeated strokes involving different arterial territories following initiation of corticosteroid therapy, despite resolution of cranial symptoms and normalization of inflammatory markers. Subsequent investigation suggested persisting arteritis as the cause of these strokes. The cases revealed the limitations of laboratory tests or imaging techniques in determining the cause of stroke in recently diagnosed GCA. There is a need to develop effective means of monitoring GCA activity and to determine the most effective treatment approach in this circumstance.


Asunto(s)
Arteritis de Células Gigantes/complicaciones , Arteritis de Células Gigantes/tratamiento farmacológico , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Corticoesteroides/efectos adversos , Corticoesteroides/uso terapéutico , Anciano de 80 o más Años , Biopsia , Femenino , Arteritis de Células Gigantes/patología , Humanos , Masculino , Persona de Mediana Edad , Prednisolona/efectos adversos , Prednisolona/uso terapéutico , Recurrencia , Factores de Riesgo , Arterias Temporales/patología
6.
Ann Neurol ; 67(6): 761-70, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20517937

RESUMEN

OBJECTIVE: Variant Creutzfeldt-Jakob disease (vCJD), a novel form of human prion disease, was recognized in 1996. The disease affected a younger cohort than sporadic CJD, and the early clinical course was dominated by psychiatric and sensory symptoms. In an attempt to aid diagnosis and establish standardization between surveillance networks, diagnostic criteria were established. These were devised from the features of a small number of cases and modified in 2000 as the clinical phenotype was established. Since then, only minor changes have been introduced; revalidation of the criteria in the current format is overdue. METHODS: Included in this study are autopsy/cerebral biopsy-proven cases of vCJD referred to the National CJD Surveillance Unit (NCJDSU) between 1995 and 2004 and suspect cases in which an alternative diagnosis was identified following autopsy/cerebral biopsy. RESULTS: Over the 10-year period, 106 definite cases of vCJD and 45 pathologically confirmed "noncases" were identified from the archives of the NCJDSU. The median age at onset of the cases was significantly younger than that of the noncases (27 years [range, 12-74 years] vs 43 years [range, 10-64 years]), and the median duration of illness was significantly shorter (14 months [range, 6-39 months] vs 22 months [range, 2-139 months]). The most commonly identified core clinical feature in cases was dementia; persistent painful sensory symptoms were the least frequent. Eighty-eight of 106 (83%) vCJD cases were retrospectively classified as probable in life, 6 cases were classified as possible. Most cases were classified as probable on the basis of core clinical features and brain magnetic resonance imaging. To date, the diagnostic criteria remain 100% specific, with no autopsy/cerebral biopsy-proven noncases classified as probable in life. INTERPRETATION: This study confirms that the diagnostic criteria for vCJD are sensitive and specific and provide a useful standard framework for case classification in a surveillance setting.


Asunto(s)
Síndrome de Creutzfeldt-Jakob/clasificación , Síndrome de Creutzfeldt-Jakob/diagnóstico , Adolescente , Adulto , Anciano , Biopsia/métodos , Niño , Síndrome de Creutzfeldt-Jakob/fisiopatología , Demencia/diagnóstico , Electroencefalografía/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto Joven
8.
AJNR Am J Neuroradiol ; 24(8): 1560-9, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-13679271

RESUMEN

BACKGROUND AND PURPOSE: Variant Creutzfeldt-Jakob disease (vCJD) is a rare but important cause of dementia and death in young patients and is causally linked to bovine spongiform encephalopathy. Symmetrical hyperintensity in the pulvinar (posterior) nuclei of the thalamus (pulvinar sign) on brain MR images was described as a specific, noninvasive, diagnostic sign of vCJD in a previous small series. This purpose of this larger study was to evaluate this sign prospectively and further define the MR imaging characteristics of vCJD. METHODS: As part of the ongoing surveillance program in the United Kingdom, MR images of suspected cases of vCJD were collected during a 6-year period. All available images were assessed prospectively by one observer for the presence of the pulvinar sign. Images of neuropathologically confirmed cases were then assessed independently by two neuroradiologists for the degree of hyperintensity of the pulvinar on images of different MR sequences, and for the presence of abnormal hyperintensity in other areas of the brain. Discrepancies were reviewed jointly and a consensus opinion formed. RESULTS: Prospective analysis identified the pulvinar sign in 74 of 82 cases of vCJD. In the retrospective study, the pulvinar sign, as defined by hyperintensity of the pulvinar relative to the anterior putamen, was present on seven (9%) of 75 T1-weighted, 77 (71%) of 108 T2-weighted, 47 (81%) of 58 proton density-weighted, and 30 (100%) of 30 fluid-attenuated inversion-recovery (FLAIR) images. Diffusion-weighted images were available in two cases and were positive for the pulvinar sign in one. Other features were hyperintensity of the dorsomedial thalamic nuclei (93%), caudate head (40%), and periaqueductal gray matter (83%) on FLAIR images. CONCLUSION: In the appropriate clinical context, demonstration of the pulvinar sign on MR images is a highly accurate diagnostic sign for vCJD. FLAIR sequence is more sensitive than other sequences. Positive MR images may obviate more invasive diagnostic tests in most cases.


Asunto(s)
Síndrome de Creutzfeldt-Jakob/diagnóstico , Imagen por Resonancia Magnética , Pulvinar/patología , Encéfalo/patología , Consenso , Síndrome de Creutzfeldt-Jakob/patología , Humanos , Variaciones Dependientes del Observador , Vigilancia de la Población , Estudios Prospectivos , Estudios Retrospectivos , Escocia
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