The IGCP 509 Database System: Design and application of a tool to capture and illustrate litho- and chrono-stratigraphic information for Palaeoproterozoic tectonic domains, large igneous provinces and ore deposits; with examples from southern Africa

The IGCP 509 project is collating global information for the Palaeoproterozoic era through the activities of numerous international collaborators. A database system (StratDB) and web interface has been designed to facilitate this process with links to an existing geochronology database (DateView). As a result, all information captured will remain available in a digital format for future researchers. The philosophy and design of the database and some of the outputs available from it are described. One of the principal features of the system is that it facilitates the construction of time-space correlation charts using an innovative application of GIS technology to nongeographic information, which permits users to query a variety of attribute information associated with lithostratigraphic units, metamorphic and deformation episodes associated with user-selected tectonic domains, large igneous provinces and major ore deposits. In the process, much of the manual labour normally associated with the construction of such charts in standard graphical or drafting packages is avoided.Associations between units, deformation, metamorphism, large igneous provinces and ore deposits may become more apparent once linked information is available for querying and investigation. Geochronological information from the DateView database may also be linked to entities stored in StratDB. GIS maps may be linked to the attribute informationin StratDB and DateView to construct a variety of time-slice maps or palaeogeographic reconstructions with the same symbology as is used in the time-space correlation charts. This database system will facilitate the dissemination of lithostratigraphic information for many countries to a broader community and will help non-specialists to easily view information for various Palaeoproterozoic tectonic domains. The system is illustrated using a preliminary compilation of information for the Palaeoproterozoic of southern Africa. The correlation charts and time-slice maps provide insights to the geological evolution of this region which emphasize some aspects and correlations which have not previously been extensively considered; for instance, possible correlation of units in the central and western zones of the Limpopo Belt (South Africa, Zimbabwe and Botswana) with the Magondi Belt of Zimbabwe and its extension into northern Botswana

Neoproterozoic to Cambrian granitoids of northern Mozambique and Dronning Maud Land Antarctica.

第2回極域科学シンポジウム/第31回極域地学シンポジウム 11月17日（木） 国立極地研究所　2階大会議

A national-scale assessment of climate change impacts on species: assessing the balance of risks and opportunities for multiple taxa

It is important for conservationists to be able to assess the risks that climate change poses to species, in order to inform decision making. Using standardised and repeatable methods, we present a national-scale assessment of the risks of range loss and opportunities for range expansion, that climate change could pose for over 3,000 plants and animals that occur in England. A basic risk assessment that compared projected future changes in potential range with recently observed changes classified 21% of species as being at high risk and 6% at medium risk of range loss under a B1 climate change scenario. A greater number of species were classified as having a medium (16%) or high (38%) opportunity to potentially expand their distribution. A more comprehensive assessment, incorporating additional ecological information, including potentially confounding and exacerbating factors, was applied to 402 species, of which 35 % were at risk of range loss and 42 % may expand their range extent. This study covers a temperate region with a significant proportion of species at their poleward range limit. The balance of risks and opportunities from climate change may be different elsewhere. The outcome of both risk assessments varied between taxonomic groups, with bryophytes and vascular plants containing the greatest proportion of species at risk from climate change. Upland habitats contained more species at risk than other habitats. Whilst the overall pattern was clear, confidence was generally low for individual assessments, with the exception of well-studied taxa such as birds. In response to climate change, nature conservation needs to plan for changing species distributions and increasing uncertainty of the future

Disentangling the Relative Importance of Changes in Climate and Land-Use Intensity in Driving Recent Bird Population Trends

Threats to biodiversity resulting from habitat destruction and deterioration have been documented for many species, whilst climate change is regarded as increasingly impacting upon species' distribution and abundance. However, few studies have disentangled the relative importance of these two drivers in causing recent population declines. We quantify the relative importance of both processes by modelling annual variation in population growth of 18 farmland bird species in the UK as a function of measures of land-use intensity and weather. Modelled together, both had similar explanatory power in accounting for annual fluctuations in population growth. When these models were used to retrodict population trends for each species as a function of annual variation in land-use intensity and weather combined, and separately, retrodictions incorporating land-use intensity were more closely linked to observed population trends than retrodictions based only on weather, and closely matched the UK farmland bird index from 1970 onwards. Despite more stable land-use intensity in recent years, climate change (inferred from weather trends) has not overtaken land-use intensity as the dominant driver of bird populations

A counterfactual approach to measure the impact of wet grassland conservation on UK breeding bird populations

Wet grassland wader populations in the United Kingdom have experienced severe declines over the last three decades. To help mitigate these declines, the Royal Society for the Protection of Birds (RSPB) has restored and managed lowland wet grassland nature reserves to benefit these and other species. However, the impact that these reserves have on bird population trends has not been experimentally evaluated, as appropriate control populations do not readily exist. In this study, we compare population trends from 1994 ‐ 2018 for five bird species of conservation concern that breed on these nature reserves with counterfactual trends using matched breeding bird survey observations. Our results showed positive effects of conservation interventions for all four wader species that these reserves aim to benefit: Lapwing (Vanellus vanellus), Redshank (Tringa totanus), Curlew (Numenius arquata) and Snipe (Gallinago gallinago). There was no positive effect of conservation interventions on reserves for the passerine, Yellow Wagtail (Motacilla flava). We compared reserve trends with three different counterfactuals, based on different scenarios of how reserve populations could have developed in the absence of conservation, and found that reserve trends performed better regardless of the counterfactual used. Our approach using monitoring data to produce valid counterfactual controls is a broadly applicable method allowing large‐scale evaluation of conservation impact

Electron backscatter diffraction analysis of zircon: A systematic assessment of match unitcharacteristics and pattern indexing optimization

Quantitative microstructural analysis of zircon using electron backscatter diffraction (EBSD) requires a comparison of empirically collected electron backscatter patterns with theoretical patterns or “match units” derived from known crystallographic parameters. There are 23 possible crystallographic data sets for zircon, and associated match units, derived from natural and synthetic zircon and from theoretical calculations over a range of pressures and different rare earth element (REE) compositions. A systematic assessment of these match units has been undertaken by EBSD analysis of each of four zircons from a range of geological environments combined with principal components analysis and self-organizing map networks. Comparison of the different match units shows a systematic relationship across all samples that are related to changes in unit-cell dimensions associated with pressure and compositional variations. Systematic variations in the data generated from 96 EBSD maps, each comprising 10 000 electron backscatter patterns, indicate that match units associated with increasing pressure or REE dopants yield poorer quality EBSD data. The match units from low-pressure, undoped, natural zircon consistently yield the best EBSD results and are recommended for natural zircon EBSD studies irrespective of the zircon source or U content. The results provide a clear strategy for optimizing the acquisition and analysis of EBSD data from zircon from both crustal and mantle sources. In addition, the developed approach to match unit analysis may be applied to all other crystalline materials, potentially optimizing EBSD analyses from a range of materials

Metallogeny and its link to orogenic style during the Nuna supercontinent cycle

The link between observed episodicity in ore deposit formation and preservation and the supercontinent cycle is well established, but this general framework has not, however, been able to explain a lack of deposits associated with some accretionary orogens during specific periods of Earth history. Here we show that there are intriguing correlations between styles of orogenesis and specific mineral deposit types, in the context of the Nuna supercontinent cycle. Using animated global reconstructions of Nuna's assembly and initial breakup, and integrating extensive databases of mineral deposits, stratigraphy, geochronology and palaeomagnetism we are able to assess spatial patterns of deposit formation and preservation. We find that lode gold, volcanic-hosted-massive-sulphide and nickel–copper deposits peak during closure of Nuna's interior ocean but decline during subsequent peripheral orogenesis, suggesting that accretionary style is also important. Deposits such as intrusion-related gold, carbonate-hosted lead-zinc and unconformity uranium deposits are associated with the post-assembly, peripheral orogenic phase. These observations imply that the use of plate reconstructions to assess orogenic style, although challenging for the Precambrian, can be a powerful tool for mineral exploration targeting