2,219 research outputs found

    Protection of Antarctic microbial communities - 'out of sight, out of mind'

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    Recent advances in molecular biology techniques have shown the presence of diverse microbial communities and endemic species in Antarctica. Endemic microbes may be a potential source of novel biotechnologically important compounds, including, for example, new antibiotics. Thus, the scientific and biotechnological value of Antarctic terrestrial microbial habitats can be compromised by human visitation to a greater extent than previously realized. The ever-increasing human footprint in Antarctica makes consideration of this topic more pressing, as the number of locations known to be pristine habitats, where increasingly sophisticated cutting-edge research techniques may be used to their full potential, declines. Examination of the Protected Areas system of the Antarctic Treaty shows that microbial habitats are generally poorly protected. No other continent on Earth is dominated to the same degree by microbial species, and real opportunities exist to develop new ways of conceptualising and implementing conservation of microbial biogeography on a continental scale. Here we highlight potential threats both to the conservation of terrestrial microbial ecosystems, and to future scientific research requiring their study

    Debris Disks in the Scorpius-Centaurus OB Association Resolved by ALMA

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    We present a CO(2-1) and 1240 um continuum survey of 23 debris disks with spectral types B9-G1, observed at an angular resolution of 0.5-1 arcsec with the Atacama Large Millimeter/Submillimeter Array (ALMA). The sample was selected for large infrared excess and age ~10 Myr, to characterize the prevalence of molecular gas emission in young debris disks. We identify three CO-rich debris disks, plus two additional tentative (3-sigma) CO detections. Twenty disks were detected in the continuum at the >3-sigma level. For the 12 disks in the sample that are spatially resolved by our observations, we perform an independent analysis of the interferometric continuum visibilities to constrain the basic dust disk geometry, as well as a simultaneous analysis of the visibilities and broad-band spectral energy distribution to constrain the characteristic grain size and disk mass. The gas-rich debris disks exhibit preferentially larger outer radii in their dust disks, and a higher prevalence of characteristic grain sizes smaller than the blowout size. The gas-rich disks do not exhibit preferentially larger dust masses, contrary to expectations for a scenario in which a higher cometary destruction rate would be expected to result in a larger mass of both CO and dust. The three debris disks in our sample with strong CO detections are all around A stars: the conditions in disks around intermediate-mass stars appear to be the most conducive to the survival or formation of CO.Comment: 16 pages, 6 figures, accepted for publication in Ap

    Small-Group Workshops Develop Participant Commitment for Nutrient Management Planning

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    Eighty small-group workshops were organized over 3 years to lead crop and livestock producers through preparation of two-field nutrient management plans using their own farm data. Follow-up surveys quantified the adoption of recommended manure management practices and completion of nutrient management plans resulting from the workshops. The small-group format combined the effectiveness of one-on-one contact and coaching with the staff-time efficiency of group presentations of background information

    Assessing the effectiveness of specially protected areas for conservation of Antarctica's botanical diversity

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    Vegetation is sparsely distributed over Antarctica's ice-free ground, and distinct plant communities are present in each of the continent's 15 recently identified Antarctic Conservation Biogeographic Regions (ACBRs). With rapidly increasing human activity in Antarctica, terrestrial plant communities are at risk of damage or destruction by trampling, overland transport and infrastructure construction, and the impacts of anthropogenically introduced species, as well as uncontrollable pressures such as fur seal activity and climate change. Under the Protocol on Environmental Protection to the Antarctic Treaty, the conservation of plant communities can be enacted and facilitated through the designation of Antarctic Specially Protected Areas (ASPAs). In this study we examined the distribution within the 15 ACBRs of the 33 ASPAs whose explicit purpose includes protecting macroscopic terrestrial flora. Large omissions in the protection of Antarctic botanical diversity were found, with no protection of plant communities in six ACBRs and, in a further six, less than 0.4% of the ACBR area was included within an ASPA protecting vegetation. We completed the first normalised difference vegetation index (NDVI) satellite remote sensing survey to provide baseline data on the extent of vegetation cover in all ASPAs designated for plant protection in Antarctica. Protected vegetation cover within the 33 ASPAs totalled 16.1 km2 for the entire Antarctic continent, with over half of this within a single protected area. Over 96% of the protected vegetation was contained within two ACBRs, which together contribute only 7.8% of the continent's ice-free ground. We conclude that Antarctic botanical diversity is clearly inadequately protected, and call for systematic designation of ASPAs protecting plant communities across by the Antarctic Treaty Consultative Parties, the members of the governing body of the continen

    Biological invasions in terrestrial Antarctica: what is the current status and can we respond?

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    Until recently the Antarctic continent and Peninsula have been little impacted by non-native species, compared to other regions of the Earth. However, reports of species introductions are increasing as awareness of biological invasions as a major conservation threat, within the context of increased human activities and climate change scenarios, has grown within the Antarctic community. Given the recent increase in documented reports, here we provide an up-to-date inventory of known terrestrial non-native species introductions, including those subsequently removed since the 1990s, within the Antarctic Treaty area. This builds on earlier syntheses of records published in the mid-2000s, which focused largely on the sub-Antarctic islands, given the dearth of literature available at that time from the continental and maritime Antarctic regions. Reports of non-native species established in the natural environment (i.e. non-synanthropic) are mainly located within the Antarctic Peninsula region and Scotia Arc, with Deception Island, South Shetland Islands, the most impacted area. Non-native plants have generally been removed from sites of introduction, but no established invertebrates have yet been subject to any eradication attempt, despite a recent increase in reports. Legislation within the Protocol on Environmental Protection to the Antarctic Treaty has not kept pace with environmental best practice, potentially presenting difficulties for the practical aspects of non-native species control and eradication. The success of any eradication attempt may be affected by management practices and the biology of the target species under polar conditions. Practical management action is only likely to succeed with greater co-operation and improved communication and engagement by nations and industries operating in the region
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