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Global emission inventories with 1°x 1°resolution were compiled for nitrogen oxides (NO + NO2, together denoted as NO(x)), ammonia (NH3) and nitrous oxide (N2O) emissions. For NO(x) the estimated global anthropogenic emission for 1990 is about 31 million ton N year-1. The major anthropogenic sources identified include fossil fuel combustion (70%, of which the major sources are road transport and power plants) and biomass burning (20%). Natural sources contribute about 19 million ton N year-1, mainly lightning and soil processes. For NH3the estimated global emission for 1990 is about 54 million ton N year-1. The major sources identified include excreta from domestic animals and wild animals, use of synthetic N fertilisers, oceans and biomass burning. About half of the global emission comes from Asia, and about 70% is related to food production. For N2O the major sources considered include fertilised arable land, animal excreta, soils under natural vegetation, oceans, and biomass burning. The global source of N2O is about 15 million ton N2O-N year-1of which about 30% is related to food production. All three inventories are available on a sectoral basis on a 1°x 1°grid for input to global atmospheric models and on a regional/country basis for policy analysis.

Following the disturbance caused during the extraction of coal, landforms created with the overburden material and stockpiled topsoil must be rehabilitated and stabilized. Minesoils are not well studied but are generally of poor quality due to the loss of nutrients and overall structure caused by weathering and disturbance. Soil organic matter (SOM) improves soil quality in multiple ways and can be used as an indicator of soil quality. Improvement of minesoils is essential for rehabilitation success. By using soil organic carbon as a proxy for SOM, SOM levels can be monitored. However, common measurement methods do not distinguish coal and charcoal (a.k.a. black carbon (BC)) from more recent plant inputs. In order to assess the effect of rehabilitation management strategies on the quality of minesoils, a method to measure the SOM that distinguishes between newer plant inputs from coal and charcoal must be developed. The objective of this research was to develop a method to measure the amount of carbon attributable to rehabilitation, test the applicability of DRIFT to predict this carbon pool, and make observations on any trends in carbon levels.Sampling campaigns at coal minesites in the Bowen Basin, Queensland collected samples from four different mines with a range of rehabilitation ages and covering vegetation. Sampling focused on collecting small with increasingly larger increments with depth to allow detection of the movement of organic matter from the soil surface down into the soil.Thermal analysis was selected from multiple methods that quantify coal and/or BC derived carbon based on their resistance to oxidation. By quantifying coal and BC, green soil organic carbon or “green carbon”, the carbon attributable to rehabilitation, can be calculated as the difference between the total organic carbon and the sum of coal and BC derived carbon.Thermal analysis with evolved gas analysis (TA-EGA) using multivariate curve resolution (MCR) chemometric analysis was used to demonstrate the ability to distinguish between coal and BC in laboratory prepared mixed soil/coal/BC systems. MCR was able to separate components in the CO2 thermograms without prior identification of the components.TA-EGA with MCR was applied to minesoils to quantify green carbon, BC and coal and build a diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs) prediction model. The DRIFT model did not yield good results as green carbon, BC, coal, as well as other carbon measurements were poorly resolved in minesoils, indicating further work on the model and/or spectral library is required. The relatively high root mean square errors of prediction would mask small changes in green carbon; however, results suggest minesite specific calibrated models may improve predictions. As the three carbon pools are composed of a variety of materials, each with differing thermal oxidative patterns, the components identified by MCR varied somewhat from those identified in the laboratory prepared mixtures; however, the components were attributable to the pools due to their peak combustion temperatures. The BC and coal quantities attained through MCR did not concur with the recalcitrant organic carbon predictions from the Australia-wide Soil Carbon Research Programme (SCaRP) DRIFT model. This difference may be due to the use of a thermal definition as identified by MCR versus a molecular/spectroscopic definition as used by SCaRP. The use of different operational definitions of BC is reflective of the various methods used to measure BC by different laboratories and is the crux of why there is no consensus on a standard method. These methods are often biased towards measuring a particular window of the BC continuum suited for the purposes of that research field through the exploitation of a characteristic of the molecules that emerges in that window. However, as the BC continuum encompasses a wide range of thermally altered molecules, these windows often do not match each other, and as such, methods and operational definitions of BC proliferate. The results of TA-EGA with MCR as applied to minesoils from two different mines and ages of rehabilitation ranging from non-surface mined to 20 years post rehabilitation showed a general trend of decreasing amounts of green carbon from the surface downwards into the soil profile. Amounts of coal within a sampling pit was relatively stable while varying greatly between pits. This may be attributed to the high level of local heterogeneity due to the use of heavy machinery to dump loads of spoil and topsoil during the formation of the landforms. While older (>10 years) rehabilitated soils could reach carbon levels similar to and greater than nearby non-surface mined soils, the contribution by green carbon was diminished, with significantly larger amounts of coal and BC compared to non-surface mined soils. Therefore, if rehabilitation goals include returning soil carbon levels to those pre-disturbance, carbon levels must surpass pre-disturbance levels to compensate for the increase in BC and coal. Thermally defined pools for green carbon, BC, and coal produced by TA-EGA with MCR provides a new, promising method to monitor carbon changes in minesoils demonstrating the ability to differentiate the three pools concurrently and would prove useful in the monitoring of rehabilitation progress.

Assessing Biodiversity Declines Understanding human impact on biodiversity depends on sound quantitative projection. Pereira et al. (p. 1496 , published online 26 October) review quantitative scenarios that have been developed for four main areas of concern: species extinctions, species abundances and community structure, habitat loss and degradation, and shifts in the distribution of species and biomes. Declines in biodiversity are projected for the whole of the 21st century in all scenarios, but with a wide range of variation. Hoffmann et al. (p. 1503 , published online 26 October) draw on the results of five decades' worth of data collection, managed by the International Union for Conservation of Nature Species Survival Commission. A comprehensive synthesis of the conservation status of the world's vertebrates, based on an analysis of 25,780 species (approximately half of total vertebrate diversity), is presented: Approximately 20% of all vertebrate species are at risk of extinction in the wild, and 11% of threatened birds and 17% of threatened mammals have moved closer to extinction over time. Despite these trends, overall declines would have been significantly worse in the absence of conservation actions.

Abstract The rank of the Permian coals in the Gunnedah Basin has been analyzed using both petrographic and chemical methods. Apart from the effects of local igneous intrusions, a number of seams in the sequence have vitrinite reflectance values (Rv max) that deviate significantly from the trend expected with a steady downward increase in coalification. Correlation of these anomalies with interpreted depositional environments suggests that abnormally low vitrinite reflectance values in the sequence occur in seams either overlain by or intimately associated with marine strata. The three-dimensional distribution of such low reflectance values, in part of the section at least, can be related either to the lithofacies pattern or post-depositional groundwater flow associated with a major fan-delta system. Coals with anomalously high vitrinite reflectance values appear to contain material described elsewhere as pseudovitrinite, a component not previously reported in Australian Permian bituminous coals. Both low-value and high-value anomalies need to be taken into account when interpreting maturation patterns from vitrinite reflectance data. In some cases other rank indicators such as air-dried moisture may be useful to complement vitrinite reflectance in rank studies of high volatile bituminous coals. Abnormally low vitrinite reflectance values due to environmental factors such as marine influence, on the other hand, may be used to identify flooding-surface sequence boundaries in the basin for stratigraphic and sedimentological investigations.

High daily temperature range of soil (DTRsoil) negatively affects soil microbial biomass and activity, but its interaction with seasonal soil moisture in regulating ecosystem function remains unclear. For our 5-year field study in the Chihuahuan Desert, we suspended shade cloth 15 cm above the soil surface to reduce daytime temperature and increase nighttime soil temperature compared to unshaded plots, thereby reducing DTRsoil (by 5 ºC at 0.2 cm depth) without altering mean temperatures. Microbial biomass production was primarily regulated by seasonal precipitation with the magnitude of the response dependent on DTRsoil. Reduced DTRsoil more consistently increased microbial biomass nitrogen (MBN; +38%) than microbial biomass carbon (MBC) with treatment responses being similar in spring and summer. Soil respiration depended primarily on soil moisture with responses to reduced DTRsoil evident only in wetter summer soils (+53%) and not in dry spring soils. Reduced DTRsoil had no effect on concentrations of dissolved organic C, soil organic matter (SOM), nor soil inorganic N (extractable NO3 (-)-N + NH4 (+)-N). Higher MBN without changes in soil inorganic N suggests faster N cycling rates or alternate sources of N. If N cycling rates increased without a change to external N inputs (atmospheric N deposition or N fixation), then productivity in this desert system, which is N-poor and low in SOM, could be negatively impacted with continued decreases in daily temperature range. Thus, the future N balance in arid ecosystems, under conditions of lower DTR, seems linked to future precipitation regimes through N deposition and regulation of soil heat load dynamics.

The production of palm oil, soy, beef and timber are key drivers of global forest loss. For this reason, over 470 companies involved in the production, processing or distribution of these commodities have issued commitments to eliminate or reduce deforestation from their supply chains. However, the effectiveness of these commitments is uncertain since there is considerable variation in ambition and scope and there are no globally agreed definitions of what constitutes a forest. Many commitments identify high conservation value forests (HCVFs), high carbon stock forests (HCSFs) and forests on tropical peatland as priority areas for conservation. This allows for mapping of the global extent of forest areas classified as such, to achieve an assessment of the area that may be at reduced risk of development if companies comply with their zero deforestation commitments. Depending on the criteria used, the results indicate that between 34% and 74% of global forests qualify as either HCVF, HCSF or forests on tropical peatland. However, we found that the total extent of these forest areas varies widely depending on the choice of forest map. Within forests which were not designated as HCVF, HCSF or forests on tropical peatland, there is substantial overlap with areas that are highly suitable for agricultural development. Since these areas are unlikely to be protected by zero-deforestation commitments, they may be subject to increased pressure resulting from leakage of areas designated as HCVF, HCSF and tropical peatland forests. Considerable uncertainties around future outcomes remain, since only a proportion of the global market is currently covered by corporate commitments. Further work is needed to map the synergies between corporate commitments and government policies on land use. In addition, standardized criteria for delineating forests covered by the commitments are recommended.

Benthic gross primary productivity (GPP), net primary production (NP), and respiration (R) were measured seasonally in each of 12 major benthic habitats in 3 southeast Australian estuaries, along with a suite of biological, physical, and chemical parameters to construct a benthic carbon budget and to elucidate controls over benthic metabolism. We also tested the performance of an artificial neural network (ANN) model in predicting benthic metabolism from the suite of measured parameters, and compared model performance to traditional stepwise regression methods. Carbon budgets indicated that macrophyte communities made the greatest contribution to whole system benthic metabolism (51 to 79% of gross productivity and 38 to 74% of respiration), and net benthic metabolism of the 3 estuaries ranged from −25 to ~90 g C m−2 yr−1. Metabolism in non-macrophyte communities was tightly coupled to light, temperature, organic matter supply, and benthic algal biomass, and metabolism in macrophyte communities was coupled predominantly to temperature and light. ANN outperformed stepwise regression for all benthic metabolic parameters in both macrophyte and non-macrophyte habitats. Root mean square errors of ANN were up to 3-fold lower than stepwise regression models, indicating the potential use of ANN in modeling ecosystem-scale metabolism. We used ANN models to predict systemwide changes in benthic net production associated with an increase in temperature of 1 to 2°C. Model results indicate that system-wide net production increased with temperature, indicating that carbon burial in, and/or export from estuaries may increase as a result of increasing water temperature associated with climate change.