997 resultados para island ecosystems


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Climate change is expected to have significant impacts on hydrologic regimes and freshwater ecosystems, and yet few basins have adequate numerical models to guide the development of freshwater climate adaptation strategies. Such strategies can build on existing freshwater conservation activities, and incorporate predicted climate change impacts. We illustrate this concept with three case studies. In the Upper Klamath Basin of the western USA, a shift in land management practices would buffer this landscape from a declining snowpack. In the Murray–Darling Basin of south-eastern Australia, identifying the requirements of flood-dependent natural values would better inform the delivery of environmental water in response to reduced runoff and less water. In the Savannah Basin of the south-eastern USA, dam managers are considering technological and engineering upgrades in response to more severe floods and droughts, which would also improve the implementation of recommended environmental flows. Even though the three case studies are in different landscapes, they all contain significant freshwater biodiversity values. These values are threatened by water allocation problems that will be exacerbated by climate change, and yet all provide opportunities for the development of effective climate adaptation strategies.

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This report is the third in a series with the two previous reports published in 2006 and 2008. This report details major conservation initiatives that have occurred in Australia since the last report, in which data was current to 2006, and highlights emerging issues. A major enhancement on previous reports is the inclusion of ecosystem and threatened species gap analyses, and the reporting on Australia's protected area systems on both land and sea. We define a minimum standard for an adequate, representative, and comprehensive reserve system by sampling ecosystem and species level diversity. Using the latest protected area and national species and ecosystem spatial data, we quantify the gaps: those areas needing to move from the current reserve system to one which meets the minimum standard. We also use data provided by various parks agencies, from responses to a questionnaire or as published by the agencies, to detail financial investments in protected areas, and estimate the investment levels needed to fill the documented gaps. We also identify critical policy changes needed to more effectively fill the identified gaps.

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Surface-enhanced infrared absorption (SEIRA) spectra of manganese (III) tetraphenylporphine chloride (Mn(TPP)Cl) on metal island films were measured in transmission mode. Dependences of the enhancement factor of SEIRA on both the sample quantity and the type of evaporated metal were investigated by subsequently increasing the amount of Mn(TPP)Cl on gold and silver substrates. The enhancement increases nonlinearly with the amount of sample and varies slightly with the thickness of metal islands. In particular, the SEIRA transmission method presents an anomalous spectral enhancement by a factor of 579, with substantial spectral shifts, observed only for the physisorbed Mn(TPP)Cl that remained on a 3-nm-thick gold film after immersion of the substrates into acetone. A charge-transfer (CT) interaction between the porphyrinic Mn and gold islands is therefore proposed as an additional factor in the SEIRA mechanism of the porphyrin system. The number of remaining porphyrin molecules was estimated by calibration-based fluorescence spectroscopy to be 2.36×1013 molecules (i.e., ~2.910-11 mol/cm2) for a 3-nm-thick gold film, suggesting that the physisorbed molecules distributed very loosely on the metal island surface as a result of the weak van der Waals interactions. Fluorescence microscopy revealed the formation of microcrystalline porphyrin aggregates during the consecutive increase in sample solution. However, the immersion likely redistributed the porphyrin to be directly attached on the gold surface, as evidenced by an absence of porphyrinic microcrystals and the observed SEIRA enhancement. The distinctive red shift in the UV-visible spectra and the SEIRA-enhanced peaks indicate the presence of a preferred orientation in the form of the porphyrin ring inclined with respect to the gold surface.

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The development of a comprehensive, adequate and representative reserve system is the key objective of the National Reserve System, and is supported by all Australian States and Territories. In Victoria, the purchase of private land for incorporation into the parks and reserves system assists in the protection of some of the State’s most endangered ecosystems. This article outlines the ecological attributes of private land purchased for addition to the Victorian public protected area system in 2006 and 2007.

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Aims : To describe the incidence of parentally reported illness in otherwise healthy South Island toddlers; characterise the predictors of illness; and determine whether there was a relationship between teething and illness in this population.

Methods :
A 20-week randomised controlled trial was conducted on 1-year-old children (n=225) from Otago and Southland between February 2004 and December 2005. Information on symptoms of morbidity, occurrence of teething, and childcare attendance were recorded daily throughout the intervention period. Morbidity symptoms were categorised into respiratory illness (RI), gastrointestinal illness (GII), ear infection, and total illness, and the number and duration of events were determined.

Results :
The mean (SD) number of total illnesses was 3.4 (2.3) per 20 weeks, with an average duration of 4.5 days. Episodes of RI were most common (50% of total illness events), and tended to be the longest in duration (mean of 3.7 days). Having siblings aged less than 5 years (23% increase, 95%CI 6%–42%, p=0.007) and attending childcare (72% increase, 95%CI 38%–113%, p<0.001)), were positively associated with the number of total illness events but not duration. In addition, teething was positively associated with total events (OR 1.94, 95%CI 1.45–2.60, p<0.001), RI events (OR 2.03, 95%CI 1.41–2.93, p<0.001) and GII events (OR 1.90, 95%CI 1.36–2.67, p<0.001).

Conclusion :
This study has shown that illness (particularly RI) is common in the second year of life. It has also confirmed that attending childcare and having siblings aged under 5 years increases the number of illness events. An association between teething and the occurrence of illness was also seen but the exact nature of this relationship requires verification.

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Writing in the lee of first-wave feminism and in an era of nation-invention, the Irish Ascendancy novelist, Emily Lawless, and the aggressively Australian Miles Franklin (of Irish, English and German extraction and coming from families who were pastoralists) wrote novels of adolescence, respectively, 'Grania: the Story of an Island' (1892) and 'My Brilliant Career' (1901). Similar and different in many ways, they both wrote as women and self-consciously inserted themselves into nation-inscribing projects with an eye to overseas readerships, and they played fast and loose with class. Curiously, both contributed to the process of transforming 'nowhere-places' into iconic nationalist places: Franklin put the Monaro on the map (a region that was a nationalist icon before the 'Red Centre' usurped its place); and Lawless wrote in ethnographic ways about the Aran Islands more than a decade before J.M. Synge tramped westward in search of the 'Peasant Quality', so beloved of the Abbey Theatre playwrights and audiences. Most compellingly, they wrote of the near-pathologies of masculinities within nationalist agendas, and of marriage and sexuality. This article examines the novels comparatively and contrastively and asks uncomfortable questions about why and how their interventions were untimely.

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Writing in the lee of first-wave feminism and in an era of nation-invention, the Irish ascendancy novelist, Emily Lawless, and the aggressively Australian Miles Franklin (of Irish, English and German extraction and coming from families who were pastoralists) wrote novels of adolescence, Grania: The Story of an Island (1892) and My Brilliant Career (1901) respectively. Similar and different in many ways, they both write as women, and self-consciously insert themselves into nation-inscribing projects with an eye to overseas readerships, and they play fast and loose with class. Curiously, both contributed to the process of transforming ‘nowhere-places’ into iconic nationalist places: Franklin put the Monaro on the map (a region that was a nationalist icon before the ‘Red Centre’ usurped its place); and Lawless wrote in ethnographic ways about the Aran Islanders more than a decade before Synge tramped westward in search of the ‘Peasant Quality’ so beloved of the Abbey playwrights and audiences. Most compellingly, they write of the near-pathologies of masculinities within nationalist agendas, and of marriage and sexuality. This paper examines the novels comparatively and contrastively and asks uncomfortable questions about why and how their interventions were untimely.

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Predicting and managing ecological response to a changing climate is often limited by an incomplete understanding of response thresholds and biogeographic differences. For example, step changes in rainfall and runoff, and threshold dynamics and hysteresis in ecological response make projection of future conditions difficult. To combat these constraints we propose that biophysical data across exiting climatic gradients can be used in a space-for-time substitution to predict climate-related ecological response elsewhere. This method builds on previous attempts at space-for-time substitution by using patterns in physical and physicochemical data to explain biological differences across the spatial gradient, then using those patterns to formulate hypotheses of temporal ecological response and finally testing those hypotheses on temporal data available in a second, similar region of interest. 

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After an extended period of sporadic sightings of small numbers of king penguins at the Falkland Islands, they established themselves on Volunteer Point, situated at the north-east of the islands, by the late 1970s. By 1980, a small breeding population was present which yielded some 40 fledglings during that same year. Since 1991, the population has been monitored annually and the resulting fledgling counts analysed to assess population trends. The population demonstrated a significant increase over the past three decades, at about 10% per annum, with time explaining 75% of the variation in count data. The current population is estimated to be 720 breeding pairs. Despite several authors having alluded to the existence of a large colony of king penguins at the Falklands prior to human exploitation, we found no evidence in support of this. We furthermore found no evidence in the literature in support of exploitation for king penguin oil during the 19th century. Unlike at other breeding sites, increasing numbers of king penguins at the Falklands is consequently unlikely to be a recovery response following exploitation, but rather an indication of either increased immigration or of improved feeding conditions.

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Like the dilapidated castles of gothic fiction the works in Joel Zika’s Pleasure Island take architectural elements from a bygone era and create a new sublime spatial experience. Pleasure Island refers to the place where young boys are taken in the 18th century children’s story Pinocchio. It is a place where every temptation and vice has been given physical form in the façades of amusement rides, arcades and bars.

In the contemporary cultural context we revel in the symbols of extreme fears and emotion that the gothic used so well. Ghosts and skeletons are part of our visual language and speak of an underlying moral position perhaps better hidden than in generations past. The façade encapsulates the journey that awaits the entrant, an over the top sales pitch to make you come and explore. Our attraction to vice and the temptation of the commercial combine playfully in these works to create a theme park within the gallery.