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The restoration and construction of wetlands offer opportunities to rewet soils, inhibit decomposition, and enhance nutrient retention in decomposing litters. Here, we report the decomposition rates and nutrient dynamics of macrophyte litters in intact, restored, and constructed wetlands. A 2.1‐year litterbag experiment of four common freshwater macrophytes (Phalaris arundinacea, Phragmites australis, Scirpus cyperinus, and Typha latifolia) was conducted in eight freshwater marshes (three intact, four restored, and one constructed) within three sites in Manitoba and Ontario, Canada, which varied in restoration age, inundation periods, and surrounding land uses. Litter mass loss and N and P dynamics were measured. Litter decomposition rates (k) followed the order of P. arundinacea (0.42 ± 0.03 year−1) > T. latifolia (0.31 ± 0.03 year−1) > P. australis (0.19 ± 0.01 year−1) > S. cyperinus (0.13 ± 0.01 year−1) in most wetlands and were positively correlated to the initial litter N concentration. Litters decomposed fastest under seasonally inundated conditions rather than permanent inundation. N and P retention in litters were significantly affected by both initial litter N and P concentration and wetland surrounding land uses. After 2.1 years of decomposition, the N:P ratio of all litters converged to 20 to 28:1, regardless of the initial litter N:P ratio or N or P concentrations. The effectiveness of wetland restoration in slowing decomposition and enhancing nutrient accumulation depends on the quality of the input litters and wetland characteristics, including inundated periods and surrounding anthropogenic disturbances. [ABSTRACT FROM AUTHOR]

Summary: Ericaceous shrubs adapt to the nutrient‐poor conditions in ombrotrophic peatlands by forming symbiotic associations with ericoid mycorrhizal (ERM) fungi. Increased nutrient availability may diminish the role of ERM pathways in shrub nutrient uptake, consequently altering the biogeochemical cycling within bogs.To explore the significance of ERM fungi in ombrotrophic peatlands, we developed the model MWMmic (a peat cohort‐based biogeochemical model) into MWMmic‐NP by explicitly incorporating plant‐soil nitrogen (N) and phosphorus (P) cycling and ERM fungi processes. The new model was applied to simulate the biogeochemical cycles in the Mer Bleue (MB) bog in Ontario, Canada, and their responses to fertilization.MWMmic_NP reproduced the carbon(C)–N–P cycles and vegetation dynamics observed in the MB bog, and their responses to fertilization. Our simulations showed that fertilization increased shrub biomass by reducing the C allocation to ERM fungi, subsequently suppressing the growth of underlying Sphagnum mosses, and decreasing the peatland C sequestration. Our species removal simulation further demonstrated that ERM fungi were key to maintaining the shrub–moss coexistence and C sink function of bogs.Our results suggest that ERM fungi play a significant role in the biogeochemical cycles in ombrotrophic peatlands and should be considered in future modeling efforts. See also the Commentary on this article by Barel & Robroek, 238: 5–7. [ABSTRACT FROM AUTHOR]

Child safety is now a national policy priority in Australia. Extensive enquiries and reviews have escalated legislative and policy responses focused on developing, maintaining and monitoring "child safe" organisations. The recommendations of the Royal Commission into Institutional Responses to Child Sexual Abuse point to the importance of cultural conditions within organisations in supporting child safety and the need for responsive change in some organisations. Drawing on a recent policy analysis, undertaken as part of a larger Australian Research Council Discovery Project, this article examines how children and safety are constructed, within and across relevant state and federal government policies in Australia, and the implications of this. Distinctions are drawn between conceptualisations of children within the broader education policy context and two specific policy contexts in which children are considered particularly vulnerable to abuse – out‐of‐home care and disability. The findings indicate that policy discourses of "child safe" potentially foster different emphases and approaches in organisations. These have implications for the way children are positioned in relation to their safety, how their rights are recognised and implemented, and what is required to foster cultural conditions within organisations to best support children's safety and wellbeing. [ABSTRACT FROM AUTHOR]

Keeping children safe from harm is a national policy priority in Australia. Extensive inquiries and reviews have highlighted institutions' persistent failures to respond ethically and appropriately to child abuse and its life‐long impacts on survivors. Policy efforts now reflect considerable emphasis on safeguarding children, including through the development of 'child safe' organisations. The realisation of these policy aspirations requires close attention to how 'child safe' is conceptualised and operationalised in different organisational contexts. Drawing on an analysis of policy in Australia and other international jurisdictions, namely New Zealand, the United Kingdom and Ireland, this article engages critically with the notion of 'child safe' in policy, to explore who is to be safe, from what and how, in organisational settings. The findings suggest emergent discourses of 'child safe' are bound up with particular constructions of both children and safety, reflect current social and political understandings and agendas, and have implications for organisations' approaches to safety. Ensuring the safety of children in Australia and other jurisdictions requires continuing scrutiny of policy implementation to make sure current policy efforts are not reduced to compliance‐based imperatives that protect organisations, but fail to create the cultural conditions that enhance children's wellbeing and safety. [ABSTRACT FROM AUTHOR]

Domestic and family violence is a significant issue experienced by many children that can have severe detrimental impacts to their health, development, and well‐being. Despite the significance of this issue, it is only recently that children have been included in research that seeks to understand the impacts that domestic and family violence may have on their lives. This paper reports on the findings of a meta‐synthesis, which explored qualitative research about children's experiences of domestic and family violence. Thirty‐two studies, including from the United Kingdom, North America, and Australia were included for review. The meta‐synthesis found that children describe domestic violence as being a complex, isolating, and enduring experience that often results in disruption, losses, and challenges to their significant relationships. Children's common feelings of fear, worry, powerlessness, and sadness were also uncovered, in addition to the strategies they employed to try and facilitate the safety and emotional well‐being of themselves and their family. Children's wants and needs are also highlighted. The findings demonstrate that despite the increasing interest in children's experiences of domestic and family violence, qualitative research remains limited, with many gaps evident. Implications for research, policy, and practice are considered. [ABSTRACT FROM AUTHOR]

The fruticose lichens Cladina stellaris and Cladina rangiferina, form thick mats that can cover large areas of northern peatlands (above c. 50° latitude), including the extensive peatlands of the Hudson Bay Lowland (HBL) in Canada, where lichens may cover up to 50% of the landscape. Despite the abundance of lichens in northern peatlands, our understanding of their role within peatland ecosystems, and peat accumulation in particular, is limited.We investigate the potential effect of these mat‐forming lichens on peat production and decomposition processes, using field data from an ombrogenous bog in the HBL and laboratory analyses. We hypothesize that (a) production in lichen‐shrub hummocks is less than in Sphagnum‐shrub hummocks; (b) the decay of lichen litter is faster than that of Sphagnum moss, so the mass litter input to the peat profile is reduced; and (c) faster decomposition of the underlying peat is stimulated by lichen leachates, resulting in greater mass loss.We found that thick lichen mats alter vegetation composition in peatlands, reducing Sphagnum cover and inhibiting the growth of small shrubs. Coupled with low lichen productivity that is constrained by moisture conditions, production for lichen‐shrub hummocks is significantly smaller than for Sphagnum‐shrub hummocks, confirming hypothesis (a). Our data also support hypothesis (b), with chemical analyses of lichen mats and leachates from lichen mats indicating faster decay of lichens compared to Sphagnum moss, and therefore reduced mass litter input to the peat profile in lichen‐dominated hummocks. Although we found no evidence to suggest leachates from lichens enhance decomposition processes in peatlands (hypothesis c), larger dry bulk densities for peat under lichen mats indicate a loss of structural integrity and potential collapse of the peat column.Synthesis. As production of new material added to the peat column is less in lichen‐dominated hummocks, local peat accumulation slows or ceases, representing a potential temporary limit to peat growth. Our results highlight the importance of lichens as a vegetation feedback in peatland development, with thick mats probably constraining or reducing hummock height relative to adjacent, lichen‐free hollows. Our findings highlight the importance of lichens as a vegetation feedback in the development of northern peatlands. In lichen‐dominated hummocks, production of new material added to the peat column is less, causing local peat accumulation to slow or cease. This represents a temporary limit to peat growth, with thick lichen mats probably constraining or reducing hummock height relative to adjacent, lichen‐free hollows. [ABSTRACT FROM AUTHOR]

Carbon (C), hydrogen (H), and oxygen (O) form ~90% by mass of peat, a product of the input of plant tissues and litter and the output of decomposition under aerobic and anaerobic conditions. We examined patterns of these elements, as the O:C and H:C atomic ratios, in over 1,300 peat samples collected from over 400 profiles in Ontario, Canada, representing bogs, fens, and swamps. The overall O:C ratio decreased from the surface (0.6 to 0.7) to ~0.5 at a depth of 50 cm and showed little further change to a depth of 5 m. In contrast, the H:C ratio decreased only slightly (1.30 to 1.25) over the top 1 m and showed no further significant decline with depth. The C oxidative state (Cox) and oxidation ratio showed strong decreases and increases, respectively, with depth with most changes occurring in the top 0.5 m. The O:C ratio, and Cox and oxidation ratio values were significantly correlated with the von Post humification index, with most changes occurring in index values 1 through 4, the latter representing a slight degree of decomposition. Collation of the Ontario peats with other data sets revealed the very large range in O:C and H:C values, with a general decrease from temperate to tropical and subtropical peatlands. Estimation of the O:C and H:C ratios of input (litter) and output (mineralization to CO2, methanogenesis to CH4 and CO2, and loss as dissolved organic C) allowed an estimation of the degree of decomposition or C loss. Plain Language Summary: Carbon, hydrogen, and oxygen form about 90% of the mass of peat, derived from the decomposition of dead plant and animal material. Using a large database from bog, fen, and swamp peatlands in Ontario and in Europe, North America, and Indonesia, we show that the ratios, or stoichiometry, between these three elements is a function of their input in litter and decomposition pathways and intensity. We suggest that the ratios, particularly the atomic oxygen:carbon ratio, can be used to predict the proportion of carbon that has been lost through decomposition and peat formation. Key Points: C, H, and O form 90% of peat mass; O:C but not H:C ratio decreases with depth in Ontario peatlandsThe O:C and H:C ratios are a function of their input in litter and pathways and degree of decomposition in peat formationThe O:C ratio and stoichiometry of decomposition may be used to predict the proportion of C that has been lost since peat formation [ABSTRACT FROM AUTHOR]

Abstract: This article presents findings from a study with 467 child protection practitioners in Australia to determine their practice responses and views on children's participation. The practitioners, recruited from 5 state jurisdictions, completed an online survey responding to case studies designed to determine the extent to which they would seek and include children's perspectives in decision making, and their confidence in talking to children. We report on practitioners' responses to a case study of a 5‐year‐old girl with suspicious bruising where the mother reports domestic violence. Based on previous research, it was hypothesized that the child's young age would lead to low levels of confidence in consulting with the child and giving weight to her perspective. In contrast to the findings of other research, our results show that almost all workers report that they would speak with the child, would be confident doing so, and would give weight to the child's perspective. Our discussion explores the potential reasons for the difference in these findings compared with other research, including the experience of practitioners, increased child‐centred policy in Australia, multiple understandings of participation, and variation in children and practitioner views of participation. [ABSTRACT FROM AUTHOR]

Electric system operators are increasingly concerned with the potential system-wide impacts of the large-scale integration of distributed energy resources including voltage control, protection coordination, and equipment wear. This prompts a need for new simulation techniques that can simultaneously capture all the components of these large integrated smart grid systems. This study describes a novel platform that combines three emerging research areas: power systems co-simulation, power hardware in the loop (PHIL) simulation, and lab--lab links. The platform is distributed, real-time capable, allows for easy internet-based connection from geographically-dispersed participants, and is software platform agnostic. The authors demonstrate its utility by studying real-time PHIL co-simulation of coordinated solar photovoltaic (PV) firming control of two inverters connected in multiple electric distribution network models, prototypical of US and Australian systems. The novel transpacific closed-loop system simulation was conducted in real time using a power network simulator and physical PV/battery inverter at power at the National Renewable Energy Laboratory in Golden, CO, USA and a physical PV inverter at power at the Commonwealth Scientific and Industrial Research Organisation's Energy Centre in Newcastle, NSW, Australia. This capability enables smart grid researchers throughout the world to leverage their unique simulation capabilities for multi-site collaborations that can effectively simulate and validate emerging smart grid technology solutions. [ABSTRACT FROM AUTHOR]

Determining the plant traits that best predict carbon (C) storage is increasingly important as global change drivers will affect plant species composition and ecosystem C cycling. Despite the critical role of peatlands in the global C cycle, trait-flux relationships in peatlands are relatively unknown., We assessed the ability of four non-destructive plant traits to predict carbon dioxide ( CO2) and methane ( CH4) fluxes over two growing seasons in a temperate peatland in Ontario, Canada. We examined relationships between C-fluxes and leaf area, leaf persistence (deciduous, evergreen), growth form (woody, herbaceous) and aerenchyma tissue. To explore potential inconsistencies between different scales of data aggregation, traits were analysed at the level of plots, species and microsites., CO2 fluxes showed a positive relationship with leaf area and leaf persistence, and a negative relationship with proportion of woody species. CH4 fluxes showed a positive relationship with aerenchyma and leaf area. The significance of trait-flux relationships differed based on whether data were averaged at the level of plot, species or microsite., We recommend applying leaf area as a non-destructive trait to other systems where it is not ideal to measure traits destructively. A better understanding of the relationships between above and below-ground traits is likely needed to further explain variation in ecosystem respiration and CH4 fluxes from plant traits., A is available for this article. [ABSTRACT FROM AUTHOR]

In 2012, the Australian Government announced the establishment of a Royal Commission into Institutional Responses to Child Sexual Abuse. The aim of the Royal Commission is to understand how and why sexual abuse occurred within Australian institutions and to provide guidance as to how future abuse might be prevented. The Royal Commission commissioned a mixed methods study to explore what children need to be safe and to feel safe, to explore how they determine their level of safety, and their observations about how institutions act to prevent and respond to safety issues. This article reports on the findings from the first phase of the study that involved focus groups carried out with children aged 4-17 years from different types of institutions. The discussion focused particularly on how children conceptualise safety and how they make judgments about their levels of safety. Children and young people's conceptualisation of safety had multiple dimensions, which include the idea that being safe and feeling safe are two distinct, interrelated but sometimes non-concurrent experiences; that safety is identified and experienced as a set of feelings; trusting relationships are the foundation of safety; familiarity helps children feel safe; and safe environments are those that are ordered and orderly. [ABSTRACT FROM AUTHOR]

To examine where Canadian geographers publish their research, we used data on article publication compiled from the annual Directory of the Canadian Association of Geographers for 1981-82, 1991-92, 2001-02, and 2011-12. We find a very wide range of journals (1238) is used, but many of them are rarely used. Papers published from 1981 to 2012 increased 3.7-fold with a similar increase in the number of journals used. Commercial presses have come to dominate publishing, society presses and university presses are fewer today but open access journals have become more common. Only about one quarter of the journals used have a Thompson Reuter Impact Factor (IF) but the median IF of IF-rated journals used rose from 1.56 (1981-82) to 2.23 (2011-12). The Canadian Geographer is the most frequently used journal, but over time flagship geography journals have been replaced by interdisciplinary and thematic journals. Papers published per faculty rose from an average of 0.5 yr−1 in 1981-82 to 1.7 yr−1 in 2011-12, with a large variation in publication rates per faculty across departments, reflecting the research versus teaching focus. Canadian geographers are publishing well beyond the field, engaging with much larger audiences, and reaching top journals, to the benefit of the discipline. La publication des articles de revue en géographie canadienne Une analyse des revues dans lesquelles les géographes canadiens publient leurs travaux a été réalisée à partir des données sur la publication d'articles dans l'annuaire annuel de l'Association canadienne des géographes pour les années 1981-82, 1991-92, 2001-02 et 2011-12. On constate un éventail de revues très diversifié (1238) et que plusieurs d'entre elles sont utilisées rarement. De plus, entre 1981 et 2012, les articles parus ont augmenté de 3,7 fois et le nombre de revues qui en ont publié a crÛ du même ordre. Les maisons d'édition commerciales ont fini par dominer l'industrie. Si les maisons d'édition associatives et universitaires sont moins nombreuses aujourd'hui, il est plus courant de publier dans des revues en libre accès. Thompson Reuter calcule un facteur d'impact (FI) pour environ un quart de ces revues seulement, mais le FI médian des revues indexées ayant fait paraître un article est passé de 1,56 (1981-1982) à 2,23 (2011-12). Le Géographe canadien est la revue la plus sollicitée. Les revues phares spécialisées en géographie sont graduellement remplacées par des revues interdisciplinaires et thématiques. La moyenne d'articles que chaque professeur a fait paraître a augmenté de 0,5 par an en 1981-82 à 1,7 par an en 2011-12. D'un département à l'autre, les taux de publication par professeur varient en fonction de l'importance accordée à la recherche versus l'enseignement. Les géographes canadiens publient dans divers domaines autres que la géographie, permettant ainsi d'élargir le lectorat et d'accéder aux meilleures revues, ce qui valorise la discipline. [ABSTRACT FROM AUTHOR]

Northern peatlands have stored large amounts (~500 Pg) of carbon (C) since the last glaciation. Combined with peat C are nutrients such as nitrogen (N), phosphorus (P), calcium (Ca), magnesium (Mg), and potassium (K), each of which plays an important role in plant production, litter decomposition, and the biogeochemical functioning of peatlands. Yet little attention has been given to the amounts of these nutrients stored in northern peatlands and their stoichiometry with C. Here we use data on nutrient concentrations in over 400 peat profiles in Ontario, Canada, representing bogs, fens, and swamps and their vegetation. We show that the C:N ratio is high (>40:1) in vegetation and litter but declines through the peat profiles to reach ratios between 22:1 and 29:1 in peat below 50 cm. In contrast, the C:P ratio rises from vegetation and litter (500:1 to 1300:1) to 1500:1 to 2000:1 in the lower part of the peat profile. Ratios of C to Ca, Mg, and K vary with peatland type. Most of these stoichiometric changes occur in the early stages of organic matter decomposition, where the litter structure remains intact. We estimate that ~18 Pg of N has been stored in northern peatlands since deglaciation, reflecting high N accumulation rates (~0.8 g m−2 yr−1), whereas P accumulation is small (~0.3 Pg, ~0.016 g m−2 yr−1), indicating that P is quickly recycled in the surface layers. [ABSTRACT FROM AUTHOR]

This study examined the suitability of a family of biodegradable polyurethanes (PUs) NovoSorbTM developed for the vascular stent application. These segmented PUs are formulated to be biodegradable using degradable polyester and PU blocks. A series of PUs comprising different hard segment weight percentage ranging from 60 to 100 were investigated. The mechanical properties of the PUs were evaluated before and after gamma sterilization to assess their suitability for vascular implants. The real-time (PBS/37°C/pH 7.4) hydrolytic degradation studies were carried out under sterile conditions and PU glass transition temperature, molecular weight, and mass loss at 3, 6, and 9 months were determined. The viability and growth of Human Umbilical Vein Endothelial Cells (HUVEC) on PU surfaces were determined to assess the effect of PU degradation. The effect of coating of extracellular matrix (ECM) components on cell viability was also investigated. The study showed that the PUs possess excellent mechanical properties exhibiting high tensile strength (41-56 MPa) and tensile modulus (897-1496 MPa). The PU films maintained mechanical strength during the early phase of the degradation but lost strength at latter stages. The unmodified polymer surface of each PU promotes endothelial cell growth and proliferation, with a HUVEC retention rate of >70%. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 1711-1719, 2014. [ABSTRACT FROM AUTHOR]

Wetlands are the largest natural source of atmospheric methane. Here, we assess controls on methane flux using a database of approximately 19 000 instantaneous measurements from 71 wetland sites located across subtropical, temperate, and northern high latitude regions. Our analyses confirm general controls on wetland methane emissions from soil temperature, water table, and vegetation, but also show that these relationships are modified depending on wetland type (bog, fen, or swamp), region (subarctic to temperate), and disturbance. Fen methane flux was more sensitive to vegetation and less sensitive to temperature than bog or swamp fluxes. The optimal water table for methane flux was consistently below the peat surface in bogs, close to the peat surface in poor fens, and above the peat surface in rich fens. However, the largest flux in bogs occurred when dry 30-day averaged antecedent conditions were followed by wet conditions, while in fens and swamps, the largest flux occurred when both 30-day averaged antecedent and current conditions were wet. Drained wetlands exhibited distinct characteristics, e.g. the absence of large flux following wet and warm conditions, suggesting that the same functional relationships between methane flux and environmental conditions cannot be used across pristine and disturbed wetlands. Together, our results suggest that water table and temperature are dominant controls on methane flux in pristine bogs and swamps, while other processes, such as vascular transport in pristine fens, have the potential to partially override the effect of these controls in other wetland types. Because wetland types vary in methane emissions and have distinct controls, these ecosystems need to be considered separately to yield reliable estimates of global wetland methane release. [ABSTRACT FROM AUTHOR]

Recently, methanotrophic members of the phylum V errucomicrobia have been described, but little is known about their distribution in nature. We surveyed methanotrophic bacteria in geothermal springs and acidic wetlands via pyrosequencing of 16 S rRNA gene amplicons. Putative methanotrophic V errucomicrobia were found in samples covering a broad temperature range (22.5-81.6° C), but only in acidic conditions ( pH 1.8-5.0) and only in geothermal environments, not in acidic bogs or fens. Phylogenetically, three 16 S rRNA gene sequence clusters of putative methanotrophic V errucomicrobia were observed. Those detected in high-temperature geothermal samples (44.1-81.6° C) grouped with known thermoacidiphilic ' M ethylacidiphilum' isolates. A second group dominated in moderate-temperature geothermal samples (22.5-40.1° C) and a representative mesophilic methanotroph from this group was isolated (strain LP2 A). Genome sequencing verified that strain LP2 A possessed particulate methane monooxygenase, but its 16 S rRNA gene sequence identity to ' M ethylacidiphilum infernorum' strain V4 was only 90.6%. A third group clustered distantly with known methanotrophic V errucomicrobia. Using pmoA-gene targeted quantitative polymerase chain reaction, two geothermal soil profiles showed a dominance of LP2 A-like pmoA sequences in the cooler surface layers and ' M ethylacidiphilum'-like pmoA sequences in deeper, hotter layers. Based on these results, there appears to be a thermophilic group and a mesophilic group of methanotrophic V errucomicrobia. However, both were detected only in acidic geothermal environments. [ABSTRACT FROM AUTHOR]

Lateral transport of carbon plays an important role in linking the carbon cycles of terrestrial and aquatic ecosystems. There is, however, a lack of information on the factors controlling one of the main C sources of this lateral flux, i.e., the concentration of dissolved organic carbon (DOC) in soil solution across large spatial scales and under different soil, vegetation, and climate conditions. We compiled a database on DOC in soil solution down to 80 cm and analyzed it with the aim, first, to quantify the differences in DOC concentrations among terrestrial ecosystems, climate zones, soil, and vegetation types at global scale and second, to identify potential determinants of the site-to-site variability of DOC concentration in soil solution across European broadleaved and coniferous forests. We found that DOC concentrations were 75% lower in mineral than in organic soil, and temperate sites showed higher DOC concentrations than boreal and tropical sites. The majority of the variation ( R2 = 0.67-0.99) in DOC concentrations in mineral European forest soils correlates with NH4+, C/N, Al, and Fe as the most important predictors. Overall, our results show that the magnitude (23% lower in broadleaved than in coniferous forests) and the controlling factors of DOC in soil solution differ between forest types, with site productivity being more important in broadleaved forests and water balance in coniferous stands. [ABSTRACT FROM AUTHOR]

To study vegetation feedbacks of nutrient addition on carbon sequestration capacity, we investigated vegetation and ecosystem CO2 exchange at Mer Bleue Bog, Canada in plots that had been fertilized with nitrogen (N) or with N plus phosphorus (P) and potassium (K) for 7-12 years. Gross photosynthesis, ecosystem respiration, and net CO2 exchange were measured weekly during May-September 2011 using climate-controlled chambers. A substrate-induced respiration technique was used to determine the functional ability of the microbial community. The highest N and NPK additions were associated with 40% less net CO2 uptake than the control. In the NPK additions, a diminished C sink potential was due to a 20-30% increase in ecosystem respiration, while gross photosynthesis rates did not change as greater vascular plant biomass compensated for the decrease in Sphagnum mosses. In the highest N-only treatment, small reductions in gross photosynthesis and no change in ecosystem respiration led to the reduced C sink. Substrate-induced microbial respiration was significantly higher in all levels of NPK additions compared with control. The temperature sensitivity of respiration in the plots was lower with increasing cumulative N load, suggesting more labile sources of respired CO2. The weaker C sink potential could be explained by changes in nutrient availability, higher woody : foliar ratio, moss loss, and enhanced decomposition. Stronger responses to NPK fertilization than to N-only fertilization for both shrub biomass production and decomposition suggest that the bog ecosystem is N-P/K colimited rather than N-limited. Negative effects of further N-only deposition were indicated by delayed spring CO2 uptake. In contrast to forests, increased wood formation and surface litter accumulation in bogs seem to reduce the C sink potential owing to the loss of peat-forming Sphagnum. [ABSTRACT FROM AUTHOR]

Children who accompany their parents or guardians during a period of homelessness make up 37% (more than one in three) of all people accessing the Supported Accommodation Assistance Program (SAAP) services. This paper describes an Australian qualitative study that explored the experiences of children who accompanied their families during periods of homelessness. It focuses particularly on what children and young people say they want from the services that they come in contact with; particularly specialised homelessness services such as housing support services and refuges. Key themes that emerged from the research include: the need for services to engage with children as individuals in their own right, to listen to and acknowledge their stories, to have services that meet their individual needs, to act and respond when children feel unsafe and for workers who can provide support to children to talk to parents about what is going on. Children and young people wanted workers to know that they felt their parents were doing their best to keep them safe. They focused on what their parents could do and did do rather than what they were not able to provide. They called on the human service system to do the same. [ABSTRACT FROM AUTHOR]

Theoretical accounts of autism have hypothesized links between arousal and behavior, but research translations of theory to real-world contexts have been limited. In this single-subject experimental analysis, a school-age subject chose between high and low arousing activities with real-time monitoring of behavior and heart rate (HR). Time series statistical analysis showed significant changes in HR associated with activity type and no association with motor movement. Sequential analysis showed that activity choice and HR were significantly associated (i.e., activity choice sequentially dependent with the preceding level of HR). Highly arousing activities were more likely to be chosen following high HR and vice versa. Results provide evidence of the feasibility of an integrative biobehavioral approach to understand behavior in neurodevelopmental disorders. [ABSTRACT FROM AUTHOR]

We investigated soil carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) exchanges in an age-sequence (4, 17, 32, 67 years old) of eastern white pine ( Pinus strobus L.) forests in southern Ontario, Canada, for the period of mid-April to mid-December in 2006 and 2007. For both CH4 and N2O, we observed uptake and emission ranging from −160 to 245 μg CH4 m−2 h−1 and −52 to 21 μg N2O m−2 h−1, respectively (negative values indicate uptake). Mean fluxes from mid-April to mid-December across the 4, 17, 32, 67 years old stands were similar for CO2 fluxes (259, 246, 220, and 250 mg CO2 m−2 h−1, respectively), without pattern for N2O fluxes (−3.7, 1.5, −2.2, and −7.6 μg N2O m−2 h−1, respectively), whereas the uptake rates of CH4 increased with stand age (6.4, −7.9, −10.8, and −23.3 μg CH4 m−2 h−1, respectively). For the same period, the combined contribution of CH4 and N2O exchanges to the global warming potential (GWP) calculated from net ecosystem exchange of CO2 and aggregated soil exchanges of CH4 and N2O was on average 4%, <1%, <1%, and 2% for the 4, 17, 32, 67 years old stand, respectively. Soil CO2 fluxes correlated positively with soil temperature but had no relationship with soil moisture. We found no control of soil temperature or soil moisture on CH4 and N2O fluxes, but CH4 emission was observed following summer rainfall events. LFH layer removal reduced CO2 emissions by 43%, increased CH4 uptake during dry and warm soil conditions by more than twofold, but did not affect N2O flux. We suggest that significant alternating sink and source potentials for both CH4 and N2O may occur in N- and soil water-limited forest ecosystems, which constitute a large portion of forest cover in temperate areas. [ABSTRACT FROM AUTHOR]

The cultivation of reflective practice has become a commonly accepted goal of theological education. However, theological educators must face the challenge of teaching and assessing reflective practice. Hypothesizing that this concern is best addressed in community, the authors of this article devised a collaborative action-research project using Thomas Groome's “shared Christian praxis” model. They describe the ways in which they have, over the course of the project, modified their pedagogy to improve their students' reflection on practice. [ABSTRACT FROM AUTHOR]

The article offers information on the transfer of carbon dioxide and methane with respect to soil-water-atmosphere system observed at Mer peatland, Canada. It is inferred that reaction betwee surface waters and carbon dioxide and methane posed a potentially unstable global repository of Carbon to the atmosphere. Drivers and mechanisms which control Carbon releases was examined at Mer Bleue peatland to determine better management and modelling of terretrial Carbon pools. It is revealed that greenhouse gas emissions within catchment was higher during hot summer season at Mer Bleue.

We measured net ecosystem CO2 exchange (NEE), plant biomass and growth, species composition, peat microclimate, and litter decomposition in a fertilization experiment at Mer Bleue Bog, Ottawa, Ontario. The bog is located in the zone with the highest atmospheric nitrogen deposition for Canada, estimated at 0.8–1.2 g N m−2 yr−1 (wet deposition as NH4 and NO3). To establish the effect of nutrient addition on this ecosystem, we fertilized the bog with six treatments involving the application of 1.6–6 g N m−2 yr−1 (as NH4NO3), with and without P and K, in triplicate 3 m × 3 m plots. The initial 5–6 years have shown a loss of first Sphagnum, then Polytrichum mosses, and an increase in vascular plant biomass and leaf area index. Analyses of NEE, measured in situ with climate-controlled chambers, indicate that contrary to expectations, the treatments with the highest levels of nutrient addition showed lower rates of maximum NEE and gross photosynthesis, but little change in ecosystem respiration after 5 years. Although shrub biomass and leaf area increased in the high nutrient plots, loss of moss photosynthesis owing to nutrient toxicity, increased vascular plant shading and greater litter accumulation contributed to the lower levels of CO2 uptake. Our study highlights the importance of long-term experiments as we did not observe lower NEE until the fifth year of the experiment. However, this may be a transient response as the treatment plots continue to change. Higher levels of nutrients may cause changes in plant composition and productivity and decrease the ability of peatlands to sequester CO2 from the atmosphere. [ABSTRACT FROM AUTHOR]

To examine belowground carbon (C) turnover in peatlands, we measured fluxes of carbon dioxide (CO2) and methane (CH4) by chamber measurements, estimated respiration by in situ incubations of peat, and in situ production of dissolved carbon (CO2 CH4 and dissolved organic carbon, DOC) by pore water modeling at an ombrotrophic temperate bog. Ecosystem respiration (ER) averaged 205 mmol m-2 d-1 in summer and was related to temperature, but not water table position, and in situ rates of heterotrophic respiration in the unsaturated zone were also temperature-dependent, with Q10 = 5.0 - 6.4. In the saturated zone, concentrations of 0.1 - 2.5 mmol L-1 (CO2), 0 to 0.6 mmol L-1 (CH4), and <10 - 120 mg L-1 (DOC) were recorded. Turnover was dominated by DOC unrelated to respiration, which ranged from <0.5 to 7 mmol m-2 d-1 and amounted on average to < 1% of ER. Peat decomposition constants kd were 0.060 yr-1 to 0.034 yr-1 in the unsaturated and <0.002 yr-1 in the saturated zone. Monthly averages of CH4 fluxes ranged from 0 to 1.6 mmol m-2 d-1 and were higher than modeled diffusive fluxes when threshold concentrations for CH4 ebullition were recorded closer to the peatland surface. Our results suggest that the saturated zone is of little relevance to ER in this dry temperate bog and that mobilization of DOC is a potentially more relevant process. Temperature is a more important control on ER than water table position because most of the ER is generated close to the peatland surface. Concurrent, moderate increases in temperature and soil moisture are thus likely to increase losses of CO2 from ER and of CH4 from this type of peatland. [ABSTRACT FROM AUTHOR]

Northern peatlands contain up to 25% of the world's soil carbon (C) and have an estimated annual exchange of CO2-C with the atmosphere of 0.1–0.5 Pg yr−1 and of CH4-C of 10–25 Tg yr−1. Despite this overall importance to the global C cycle, there have been few, if any, complete multiyear annual C balances for these ecosystems. We report a 6-year balance computed from continuous net ecosystem CO2 exchange (NEE), regular instantaneous measurements of methane (CH4) emissions, and export of dissolved organic C (DOC) from a northern ombrotrophic bog. From these observations, we have constructed complete seasonal and annual C balances, examined their seasonal and interannual variability, and compared the mean 6-year contemporary C exchange with the apparent C accumulation for the last 3000 years obtained from C density and age-depth profiles from two peat cores. The 6-year mean NEE-C and CH4-C exchange, and net DOC loss are −40.2±40.5 (±1 SD), 3.7±0.5, and 14.9±3.1 g m−2 yr−1, giving a 6-year mean balance of −21.5±39.0 g m−2 yr−1 (where positive exchange is a loss of C from the ecosystem). NEE had the largest magnitude and variability of the components of the C balance, but DOC and CH4 had similar proportional variabilities and their inclusion is essential to resolve the C balance. There are large interseasonal and interannual ranges to the exchanges due to variations in climatic conditions. We estimate from the largest and smallest seasonal exchanges, quasi-maximum limits of the annual C balance between 50 and −105 g m−2 yr−1. The net C accumulation rate obtained from the two peatland cores for the interval 400–3000 bp (samples from the anoxic layer only) were 21.9±2.8 and 14.0±37.6 g m−2 yr−1, which are not significantly different from the 6-year mean contemporary exchange. [ABSTRACT FROM AUTHOR]

In northern ecosystems, the onset and growth of spring photosynthesis may have an important influence on the annual carbon (C) budget, yet the controls have not been clearly identified, especially for peatlands. We used a 5-year set of daily carbon dioxide (CO2) exchange measurements derived from an eddy covariance tower located at Mer Bleue, an ombrotrophic bog near Ottawa, Canada, from March to May [day-of-year (DOY) 60–150], 1999–2003. We used half-hourly measured net ecosystem exchange minus modelled ecosystem respiration to estimate daily photosynthesis, as gross ecosystem production (GEP). The onset of GEP in each year was closely related to the thinning and disappearance of the snow cover, occurring between DOY 86 and 101. GEP increased during the spring, reaching 10-day average values of between 5 and 9 g CO2 m−2 day−1 by the end of May. This increase was initially associated with moss activity ( Sphagnum and Polytrichum), followed by the evergreen shrubs. Peat temperatures in the rooting zone (10–20 cm depth) and increases in shrub leaf nitrogen and chlorophyll a concentrations contributed to this rapid increase in GEP. Examination of moderate-resolution imaging spectroradiometer (MODIS) images over several years revealed that the temporal resolution (16-day composites) was inadequate to capture the onset of GEP but estimates of gross primary productivity and photosynthesis from MODIS 8-day composites for the most part followed the pattern and magnitude of CO2 exchange observed at the tower. [ABSTRACT FROM AUTHOR]

No studies of seagrass decay have examined effects of the number of species contained within the detrital pool. Given the importance of decay for nutrient cycling and long-term productivity, we tested how three seagrass species affected decay in litterbags. Experimental results clearly showed that species identity was the predominant driver of mass loss, with total loss not differing between bags containing one, two and three species. Furthermore, we show there were also non-additive effects of mixing litter that were not predicted from single-species decay rates. The nature of the non-predictable mass loss varied both through time and with the number of species in the mixtures. This indicates that species richness indeed plays a role in this important ecosystem function but one that is of less importance than species identity. The concordance of these results with terrestrial studies suggests that mechanisms responsible for mixed-species decay rates may be broadly applicable across ecosystems. [ABSTRACT FROM AUTHOR]

This article overviews prevention and early intervention approaches focusing specifically on their relevance to the health of children and young people in Australia. Australian public health has a sound track record although concealed within the aggregate profile are a number of sub-populations with poorer health indicators. Recognition of this has increased efforts to improve the health of children and young people especially in exploring the impact of social environments within the communities where children are raised. This paper examines emerging research in this area drawing out key lessons and learning from Australian experience in the field of early intervention and prevention in community settings. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We used field measurements of methane (CH4) flux from upland and wetland soils in the Northern Study Area (NSA) of BOREAS (BOReal Ecosystem-Atmosphere Study), near Thompson, Manitoba, during the summers of 1994 and 1996 to estimate the overall CH4 emission from a 1350 km² landscape. June-September 1994 and 1996 were both drier and warmer than normal, but summer 1996 received 68 mm more precipitation than 1994, a 40% increase, and had a mean daily air temperature 0.6°C warmer than 1994. Upland soils consumed CH4 at rates from 0 to 1.0 mg m-2 d-1, with small spatial and temporal variations between years, and a weak dependence on soil temperature. In contrast, wetlands emitted CH4 at seasonal average rates ranging from 10 to 350 mg CH4 m-2 d-1, with high spatial and temporal variability, and increased an average of 60% during the wetter and warmer 1996. We used Lands at imagery, supervised classification, and ground truthing to scale point CH4 fluxes (<1 m²) to the landscape (>1000 km²). We performed a sensitivity analysis for error terms in both areal coverage and CH4 flux, showing that the small areas of high CH4 emission (e.g., small ponds, graminoid fens, and permafrost collapse margins) contribute the largest uncertainty in both flux measurements and mapping. Although wetlands cover less than 30% of the landscape, areally extrapolated CH4 flux for the NSA increased by 61% from 10 to 16 mg CH4 m-2 d-1 between years, entirely attributed to the increase in wetland CH4 emission. We conclude that CH4 fluxes will tend to be underestimated in areas where much of the landscape is covered by wetlands. This is due to the large spatial and temporal variability encountered in chamber-based measurements of wetland CH4 fluxes, strong sensitivity of wetland CH4 emission to small changes in climate, and because most remote sensing images do not adequately identify small areas of high CH4 flux. [ABSTRACT FROM AUTHOR]

Nitrogen (N) and sulfur (S) play important roles in peatlands, through their influence on plant production and peat decomposition rates and on redox reactions, respectively, and peatlands contain substantial stores of these two elements. Using peat N and S concentrations and dry bulk density and210Pb dating, we determined the rates of N and S accumulation over the past 150 years in hummock and hollow profiles from 23 ombrotrophic bogs in eastern Canada. Concentrations of N and S averaged 0.80% and 0.18%, respectively, generally increased with depth in the profile and there was a weak but significant correlation between N and S concentrations. Rates of N and S accumulation over the past 50–150 years ranged from 0.5 to 4.8 g N m−2 yr−1 and from 0.1 to 0.9 g S m−2 yr−1. There were significant but weak correlations between C, N and S accumulation rates over 50-, 100- and 150-year periods. Over the last 50 years, rates of S accumulation showed little differentiation between hummocks and hollows, whereas the pattern for N accumulation was more variable (hummock minus hollow rate ranged from−1 to+1.5 g N m−2 yr−1), with hummocks generally having a larger N accumulation rate, correlated with the rate of carbon (C) accumulation. There was a modest but significant positive correlation between 50-year rates of N accumulation and wet atmospheric deposition of N measured between 1990 and 1996, with accumulation rates about four times that of wet deposition. The difference between deposition and accumulation of N is attributed to organic N deposition, dry deposition and N2 fixation. A weaker, but still significant, correlation was observed between 50-year S accumulation and 1990–1996 wet atmospheric S deposition, with about 75% of the deposited S accumulating in the peat. A laboratory experiment with peat cores exposed to varying water table position and simulated N and S deposition, showed that on average 87% and 98% of the deposited NH4+ and NO3−, respectively, and 58% of the deposited S were retained in the vegetation and unsaturated zone of the cores, supporting the results from the field study. [ABSTRACT FROM AUTHOR]

We showed that sandy subsoils beneath peat near Ramsey Lake, MI, contained 7.5 to 8.0 kg organic C (OC) m-2 to a depth of 70 cm, compared with 1.6 to 3.6 kg m-2 in adjacent forest soils, from which the peatland had evolved through paludification. Compared with the soils beneath the forest, those beneath the peat contained similar amounts of oxalate-extractable Al (Al0) and less Fe, owing to loss of Fe under reduced leached conditions beneath the peat. Most of the extractable Al in the mineral horizons beneath peat was organically bound. Atomic pyrophosphate-extractable (Fep + Alp) Fe + Al/C ratios were smaller (<0.2:1) in the mineral horizons beneath peat than in the forest mineral subsoils (generally >0.2:1), indicating larger inputs and retention in the mineral subsoils beneath peat. Concentration of OC in subsoil samples was strongly (r² = 0.58, p < 0.001) related to the subsoil Al, null-point dissolved organic C (DOC) and clay concentrations. A DOC sorption study using peat pore water ranging from 0 to 117 mg DOC L-1 revealed null-point DOC (DOCnp) concentrations (at which there is neither gain nor loss of OC by the soil) varied from <1 to 417 mg DOC L-1 and was primarily related to Feo (negatively), Alo (negatively), and C (positively). We suggest that the increase in mineral subsoil OC beneath peat is related to the sorption of DOC carried by pore water percolating through the mineral subsoil, combined with slow rates of mineralization of sorbed DOC under anoxic conditions. [ABSTRACT FROM AUTHOR]

Abstract We measured net ecosystem CO2 exchange (NEE) in Panamá over C4 pasture plots that varied in grazing intensity. After adjusting for variation in light, there were noticeable effects of grazing-related variables on CO2 exchange that were largely dependent on the developmental stage of the plant canopy. Above-ground productivity was positively related to grazing intensity (r 2 =0.30). Two experimentally grazed fields had significantly lower standing crop biomass but no significant difference in CO2 uptake (24.2 μmol/m2 /s) compared with two ungrazed fields (20.3 μmol/m2 /s). Grazed fields had significantly lower ecosystem respiration rates (10.3 μmol/m2 /s) than did ungrazed fields (17.6 μmol/m2 /s). These results suggest that, although these pastures were possible sources of CO2 during the time intervals sampled, the size of the sources tended to be dampened by cattle grazing through reductions in ecosystem respiration. Thus, it appears that disturbance caused by cattle grazing will not always result in an increase in CO2 release from tropical pastures to the atmosphere. [ABSTRACT FROM AUTHOR]

Summary 1Above-ground biomass was measured at bog hummock, bog hollow and poor-fen sites in Mer Bleue, a large, raised ombrotrophic bog near Ottawa, Ont., Canada. The average above-ground biomass was 587 g m-2 in the bog, composed mainly of shrubs and Sphagnum capitula. In the poor fen, the average biomass was 317 g m-2 , comprising mainly sedges and herbs and Sphagnum capitula. Vascular plant above-ground biomass was greater where the water table was lower, with a similar but weaker relationship for Sphagnum capitula and vascular leaf biomass. 2Below-ground biomass averaged 2400 g m-2 at the bog hummock site, of which 300 g m-2 was fine roots (< 2 mm diameter), compared with 1400 g m-2 in hollows (fine roots 450 g m-2 ) and 1200 g m-2 at the poor-fen site. 3Net Ecosystem Exchange (NEE) of CO2 was measured in chambers and used to derive ecosystem respiration and photosynthesis. Under high light flux (PAR of 1500 µmol m-2 s-1 ), NEE ranged across sites from 0.08 to 0.22 mg m-2 s-1 (a positive value indicates ecosystem uptake) in the spring and summer, but fell to –0.01 to –0.13 mg m-2 s-1 (i.e. a release of CO2 ) during a late-summer dry period. 4There was a general agreement between a combination of literature estimates of photosynthetic capacity for shrubs and mosses and measured biomass and summer-time CO2 uptake determined by the eddy covariance technique within a bog footprint (0.40 and 0.35–0.40 mg m-2 s-1 , respectively). 5Gross photosynthesis was estimated to be about 530 g m-2 year-1 , total respiration 460 g m-2 year-1 , and export of DOC, DIC and CH4 10 g m-2 year-1 , leaving an annual C sequestration rate of 60 g m-2 year-1 . Root... [ABSTRACT FROM AUTHOR]

Presents a predictive model for bryophyte distribution, water table position and seasonal mean methane (CH4) emission for two areas of Canadian peatland. Clay Belt of Ontario; Labrador Trough of Quebec; Water table position and CH4 flux as the most important environmental variables in canonical correspondence analyses of bryophyte data.

The globalization of economic life and the restructuring of the international economy since the 1970s have generated a new social scientific interest in spatial questions but rather less interest in territorial boundaries. Much research on economic and spatial restructuring has taken place in the so-called advanced industrial states where national borders appear non-problematical. Even where national borders have been violently contested as in eastern Europe, one of the effects has been to underline the relative stability and harmony which characterize such boundaries in the West. Yet, few borders anywhere have resulted from plebiscites or democratic negotiation at international level instead, secret manipulations and some degree or threat of force are usually present. The subject of the article, Great Britain-Irish territorial border reflects not only the impact of over two decades of European Union economic integration but also the consequences of violent ethno-national conflict over the same period. As such it provides a useful arena for examining some of the apparently contradictory influences which serve to undermine and consolidate national borders and national sovereignty in contemporary Europe.