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    In 1963, the Glen Canyon Dam, in Hite Utah was completed, creating the Lake Powell reservoir along the Colorado River. The water levels of Lake Powell peaked in 1983 and have declined since, releasing over-pressure on the underlying sediment. This release in over-pressure created mud volcanoes, structures along the shoreline made of cavities that allow fluid and gases to rise to the surface and escape. Green house gases including methane are released from these structures, and to better understand how development of natural wetlands can result in unintended increased levels of greenhouse gas emissions, we asked 1) how much of each gas is generated or and whether the amount of each gas is changing through time and 2) how are these gases forming in the subsurface? We first measured the amounts of carbon dioxide (CO2), methane (CH4), and air (N) in volcano gas samples collected in 2014, 2015, and 2016. We found that from 2014 through 2016, methane levels from these volcanoes fluctuated significantly. In 2016, we looked at the amounts of carbon and hydrogen isotopes in the methane, which told us the gas is generated from microorganisms feeding on organic matter and is released during water-level fluctuations. We looked at mud volcanoes only located along the Lake Powell marina delta in Hite, Utah. The data spans geological structures restricted to one marina delta.

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    Wood block decomposition assessment at theTumbarumba Wet Eucalypt site is part of a global program looking at the influence of microbes and invertebrates on wood decay. A common protocol was developed exposing small (~400 cm3) pieces of a wood-substrate (untreated Pinus radiata) to the environment excluding and not-excluding macroinvertebrates (e.g. termites) by the use of a plastic mesh.

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    <br>This release consists of flux tower measurements of the exchange of energy and mass between the surface and the atmospheric boundary-layer using eddy covariance techniques. Data were processed using PyFluxPro (v3.4.7) as described by Isaac et al. (2017). PyFluxPro produces a final, gap-filled product with Net Ecosystem Exchange (NEE) partitioned into Gross Primary Productivity (GPP) and Ecosystem Respiration (ER).</br> <br /> The flux station is located within an area of dryland agriculture. The surrounding area is dominated by broadacre farming practices. The vegetation cover is predominantly pasture. Elevation of the site is close to 330&nbsp;m. Climate information comes from the nearby Pingelly BoM AWS station 010626 (1991 to 2016) and shows mean annual precipitation is approximately 445&nbsp;mm with highest rainfall in June and July of 81&nbsp;mm each month. Maximumum and minuimum annual rainfall is 775 and 217&nbsp;mm, respectively. Maximum temperatures range from 31.9&nbsp;°C (in Jan) to 15.4&nbsp;°C (in July), while minimum temperatures range from 5.5&nbsp;°C (in July) to 16.0&nbsp;°C (in Feb).<br /><br />

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    This dataset consists of measurements of the exchange of energy and mass between the surface and the atmospheric boundary-layer in a pastoral area using eddy covariance techniques.<br /><br /> The flux station is located within an area of dryland agriculture. The surrounding area is dominated by broadacre farming practices. The vegetation cover is predominantly pasture. Elevation of the site is close to 330 m. Climate information comes from the nearby Pingelly BoM AWS station 010626 (1991 to 2016) and shows mean annual precipitation is approximately 445 mm with highest rainfall in June and July of 81 mm each month. Maximumum and minuimum annual rainfall is 775 and 217 mm, respectively. Maximum temperatures range from 31.9°C (in Jan) to 15.4°C (in July), while minimum temperatures range from 5.5°C (in July) to 16.0 °C (in Feb).<br /><br />This data is also available at http://data.ozflux.org.au .

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    The lesser hairy-footed dunnart (<i>Sminthopsis youngsoni, Dasyuridae</i>) is a generalist marsupial insectivore in arid Australia, but consumes wolf spiders (<i>Lycosa spp., Lycosidae</i>) disproportionately often relative to their availability. This project tested the hypothesis that this disproportionate predation is a product of frequent encounter rates between the interactants due to high overlap in their diets and use of space and time. This data set focuses on dietary overlap, with diet and predatory behaviour of wolf spiders (<i>Lycosa spp.</i>), the lesser hairy-footed dunnart (<i>Sminthopsis youngsoni</i>) and prowling spiders (<i>Miturga spp.</i>, which represent other common invertebrate predators) were determined by tracking individuals and directly observing prey captures. Seventeen wolf spiders, 10 prowling spiders and 5 dunnarts were captured from Main Camp site in the Simpson Desert, south-western Queensland during 2016 with 30, 13 and 13 direct prey captures witnessed for each species respectively. This data is used for calculating overlap between prey taxa and prey size between these predators using the symmetrical version of MacArthur and Levin's and Pianka's overlap equation. However, it can also be used as a case study for calculating overlap between other species-groups.

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    Plant material decomposition in soil was investigated using two types of tea bags (Green and Rooibos) buried to 8 cm for 80-90 days across seven TERN Ecosystem Process monitoring sites between 2016 - 2017. The sites included: Great Western Woodlands, Robson Creek Rainforest, Samford Peri-Urban, Cumberland Plain, Cape Tribulation, Warra Tall Eucalypt and Tumbarumba Wet Eucalypt sites. Weight loss of tea bags was determined and contextual data collected.

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    Wood block decomposition assessment at the Warra Tall Eucalypt site is part of a global program looking at the influence of microbes and invertebrates on wood decay. A common protocol was developed exposing small (~400 cm3) pieces of a wood-substrate (untreated Pinus radiata) to the environment excluding and not-excluding macroinvertebrates (e.g. termites) by the use of a plastic mesh.

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    The lesser hairy-footed dunnart (<i>Sminthopsis youngsoni, Dasyuridae</i>) is a generalist marsupial insectivore in arid Australia, but consumes wolf spiders (<i>Lycosa spp., Lycosidae</i>) disproportionately often relative to their availability. This project tested the hypothesis that this disproportionate predation is a product of frequent encounter rates between the interactants due to high overlap in their diets and use of space and time. This data set focuses on the dietary aspect. Specifically, invertebrate pitfall trapping was employed to quantify food availability and selectivity for both wolf spiders and <i>S.youngsoni</i>. Pitfall traps were deployed along trails left by tracked individuals, as well as control trails, of both species groups in the north-western Simpson Desert, Queensland. In total, invertebrate pitfall traps were deployed along 11 <i>S.youngsoni</i> and 8 <i>lycosa</i> trails in October 2016. Invertebrates were identified to the level of "Order", except for spiders (Order: Arachnida) and bees, wasps and ants (Order: Hymenoptera) which were identified to the "Family" level using identification keys and were also counted and grouped into seven size classes. This data was used for the following analyses: [1] a two-way analysis of variance (ANOVA) to test whether total numbers of arthropods differed between trail type and species, [2] non-metric multidimensional scaling (NMDS) and [3] permutational analysis of variance (PERMANOVA) to test whether assemblages of arthropod prey and prey sizes differed between the two trail types for each species and between each species.

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    A total of 53 native Australian species (52x C3, 1x C4) were sampled from 22 plant families and 7 growth forms along a transect in WA spanning 9.56 degrees latitude and 6.85 degrees longitude. Samples were collected using the nationally-accepted AusPlots Rangelands methodology. Samples were stored to preserve isotopic signatures and analysed using standard techniques for mass spectroscopy, including internationally-calibrated standards. Technical replicates of 13% showed very low drift (0.07).

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    High quality digital site reference images are captured for the core 1 hectare vegetation plot of the site on an annual basis to provide context for researchers to understand the general layout and vegetation of the study site, and as a visual reference to monitor any changes over time. Photopoints are taken annually using the five point photo-point method. The set of images for each year usually consists of twenty images: four images taken at each corner of the plot facing each of the four cardinal points, and four images taken from the center of the plot facing each corner. <br /><br /> The site was established in 2010 in the Wombat State Forest in Central Victoria. The site is dry Eucalypt forest with main species <em>Eucalyptus obliqua</em>, <em>Eucalyptus radiata</em> and <em>Euclayptus rubida</em>. For additional site information, see https://www.tern.org.au/tern-observatory/tern-ecosystem-processes/wombat-stringybark-eucalypt-supersite/. <br /><br /> Other images collected at the site include digital hemispherical photography, phenocam time-lapse images taken from fixed under and overstorey cameras and ancilliary images of fauna and flora.