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Abstract -- We have developed a methodology for (U-Th)/He thermochronology on a variety of mineral species. With many laboratories initiating research in the area of (U-Th)/He thermochronology, we recognize that [...]

An analysis of the innovative 'farm diversification,' 'part-time farming' and 'pluriactivity' approaches used by farm businesses to increase income reveals that operators will continue to leave the farm to join small farm businesses even if offered farm-based accommodation. This is evident from a theoretical differentiation between farm-centered diversification and off-farm employment.

Sedimentary rocks along the southern margin of Australia host an important record of the break-up history of east Gondwana, as well as fragments of a deeper geological history, which collectively help inform the geological evolution of a vast and largely underexplored region. New drilling through Cenozoic cover has allowed examination of the Cretaceous rift-related Madura Shelf sequence (Bight Basin), and identification of two new stratigraphic units beneath the shelf; the possibly Proterozoic Shanes Dam Conglomerate and the interpreted Palaeozoic southern Officer Basin unit, the Decoration Sandstone. Recognition of these new units indicates an earlier basinal history than previously known. Lithostratigraphy of the new drillcore has been integrated with that published from onshore and offshore cores to present isopach maps of sedimentary cover on the Madura Shelf. New palynological data demonstrate progression from more localised freshwater-brackish fluvio-lacustrine clastics in the early Cretaceous ( Foraminisporis wonthaggiensis – Valanginian to Barremian) to widespread topography-blanketing, fully marine, glauconitic mudrocks in the mid Cretaceous ( Endoceratium ludbrookiae – Albian). Geochronology and Hf-isotope geochemistry show detrital zircon populations from the Madura Shelf are comparable to those from the southern Officer Basin, as well as Cenozoic shoreline and palaeovalley sediments in the region. The detrital zircon population from the Shanes Dam Conglomerate is defined by a unimodal ~1400 Ma peak, which correlates with directly underlying crystalline basement of the Madura Province. Peak ages of ~1150 Ma and ~1650 Ma dominate the age spectra of all other samples, indicating a stable sediment reservoir through much of the Phanerozoic, with sediments largely sourced from the Albany-Fraser Orogen and Musgrave Province (directly and via multiple recycling events). The Madura Shelf detrital zircon population differs from published data for the Upper Cretaceous Ceduna Delta to the east, indicating significant differences in sediment provenance and routing between the Ceduna Sub-basin and central Bight Basin. [ABSTRACT FROM AUTHOR]

National and regional studies of agricultural land loss in the United Kingdom have been based almost exclusively on the Agricultural Census. Few subregional investigations exist, particularly in urban fringe areas where rates of farmland conversion to non-agricultural uses are high. This paper examines land loss in a small area on the urban fringe of Birmingham and compares the relative accuracy of the Agricultural Census as a data source at the parish scale with aerial photograph and map evidence. Caution is expressed over the use of the Agricultural Census for localised studies of land loss.

Wetland snakes, as top predators, are becoming globally recognised as bioindicators of wetland contamination. Livers are the traditional test organ for contaminant exposure in organisms, but research is moving towards a preference for non-lethal tissue sampling. Snake scales can be used as an indicator of exposure, as many metals bind to the keratin. We used laser ablation with inductively coupled plasma-atomic emission spectroscopy and mass spectrometry (LA-ICP-MS) to quantify the concentrations of 19 metals and metalloids (collectively referred to 'metals' hereafter) in Western tiger snake (Notechis scutatus occidentalis) scales from four wetlands along an urban gradient, and compared them to concentrations measured in captive tiger snake scales. We conducted repeat measures to determine the concentration accuracy of each metal using LA-ICP-MS. Concentrations in wild Western tiger snake scales were significantly higher than in reference tiger snake scales for most metals analysed, suggesting accumulation from environmental exposure. We compared the scale concentrations to sediment concentrations of sampled wetlands, and found inter-site differences between mean concentrations of metals in scales parallel patterns recorded from sediment. Four metals (Mn, As, Se, Sb) had strong positive correlations with liver tissue contents suggesting scale concentrations can be used to infer internal concentrations. By screening for a larger suite of metals than we could using traditional digestive methods, we identified additional metals (Ti, V, Sr, Cs, Tl, Th, U) that may be accumulating to levels of concern in tiger snakes in Perth, Western Australia. This research has progressed the use of LA-ICP-MS for quantifying a suite of metals available in snake scales, and highlights the significance of using wetland snake scales as a non-lethal indicator of environmental contamination. Image 1 • Laser ablation can quantify concentrations of 19 metal(loid)s in snake scales. • Snake scales reflect environmental metal(loid) exposure. • Laser ablation is a low cost and sensitive method for quantifying metals in keratin. • Broad screening of metal(loid)s can identify new contaminants of concern. • Ti, V, Sr, Cs, Tl, Th and U may be accumulating in Perth tiger snakes. Laser ablation-ICP-MS can be used to accurately quantify 19 metal(loid)s in snakes scales, and can be used to monitor environmental contamination. [ABSTRACT FROM AUTHOR]