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In this case study, we used a mixed-methods approach to identify the characteristics of environmental education (EE) lessons most positively associated with students' environmental literacy outcomes at one residential EE center in the U.S. Students attending residential EE programs spend multiple days participating in numerous lessons, activities, and experiences, resulting in perhaps more opportunities to enhance students' knowledge, attitudes, skills, and behavioral intentions related to environmental literacy. To explore what teaching approaches were most effective at enhancing immediate student outcomes and to provide insights for practitioners, we observed 80 lessons, tracked 20 observable teaching approaches, and administered questionnaires to measure students' self-reported changes in environmental literacy outcomes. Correlation analyses revealed four variables related to enhanced student outcomes: affective messaging, environmental issue-focus, relevance, and effective time management. Two variables, fact-based teaching and data collection, were negatively correlated with student outcomes. Linear regression analysis with these six variables resulted in a model explaining 34% of the variance in the environmental literacy outcome. We discuss these findings and share examples of each practice from our qualitative observations. We also discuss broader applications of our mixed methods approach for the field.

We explored the relationship between the fulfillment of students' psychological needs of competence, autonomy, and relatedness; student engagement; and student outcomes related to environmental literacy at a residential environmental education (EE) center. We surveyed diverse groups of middle school students (N = 1,278) following the completion of 80 EE lessons delivered at the NorthBay Adventure Center to assess their self-reported levels of these basic psychological needs, engagement, and environmental literacy outcomes. A structural equation model supported our hypothesis that there is a positive relationship between the fulfillment of these psychological needs and student engagement, and that more engaged students report enhanced outcomes of environmental literacy. We also discovered that autonomy has a direct positive effect on student levels of environmental literacy, suggesting an important role for student autonomy. We discuss implications of these findings and the practicality of trying to fulfill student's psychological needs of competence, autonomy, and relatedness.

Abstract\nKEY POINTSAny model invoking gold fluids coming through crustal rocks at granulite facies grade or coming from the mantle is built on a misunderstanding of the way aqueous fluids interact with rocks at high temperature, above their solidus. It is not currently explained in such models how aqueous fluids pass through rocks at granulite facies grade without being involved in melting. At temperatures above 650–750 °C, crustal rocks melt in the presence of an aqueous fluid with the latter being consumed, the amount of melt generally being proportional to the amount of fluid involved. This means auriferous hydrothermal fluids are unable to infiltrate hot lower crust from the mantle. An alternative model exists that avoids this problem, at least for typical gold-only deposits, for example Kalgoorlie. It involves fluid generation by metamorphic devolatilisation in the mid-crust at the greenschist–amphibolite facies transition, at around 450 °C. This process generates significant volumes of aqueous fluid during prograde metamorphism. In the presence of carbonate and sulfide minerals, the resulting fluid is H2O–CO2–H2S dominated by low salinity, a composition conducive to gold dissolution. A strength of this model is that the fluid will become gold-bearing as it is generated. As more or less all mineral grains in the rock are involved in the devolatilisation, gold present at parts-per-billion level in grains as well as on grain boundaries is accessible to the fluid.Introduction of an aqueous fluid into the granulite facies leads to partial melting.Models sourcing gold-bearing hydrothermal fluids from the lower crust or mantle defy metamorphic principles.Metamorphic fluid evolved from the greenschist-to-amphibolite transition addresses the main characteristics found amongst typical gold-only deposits. [ABSTRACT FROM AUTHOR]

Liquid water occurs below glaciers and ice sheets globally, enabling the existence of an array of aquatic microbial ecosystems. In Antarctica, large subglacial lakes are present beneath hundreds to thousands of metres of ice, and scientific interest in exploring these environments has escalated over the past decade. After years of planning, the first team of scientists and engineers cleanly accessed and retrieved pristine samples from a West Antarctic subglacial lake ecosystem in January 2013. This paper reviews the findings to date on Subglacial Lake Whillans and presents new supporting data on the carbon and energy metabolism of resident microbes. The analysis of water and sediments from the lake revealed a diverse microbial community composed of bacteria and archaea that are close relatives of species known to use reduced N, S or Fe and CH4 as energy sources. The water chemistry of Subglacial Lake Whillans was dominated by weathering products from silicate minerals with a minor influence from seawater. Contributions to water chemistry from microbial sulfide oxidation and carbonation reactions were supported by genomic data. Collectively, these results provide unequivocal evidence that subglacial environments in this region of West Antarctica host active microbial ecosystems that participate in subglacial biogeochemical cycling.

Background: Despite an increase in international studies examining the experiences of parents with intellectual impairments and their children, few have utilised population-based data. This study investigated the behavioural and cognitive outcomes of 3-year-old US children of mothers with intellectual impairments compared with children of mothers without intellectual impairments. Methods: This study employed a secondary analysis of the Fragile Families Child and Wellbeing Study, a longitudinal birth cohort study in the US. Our analytic sample included mothers with intellectual impairments (n = 263) and a comparison group of mothers without intellectual impairments (n = 1298), as well as each sampled mother's focal child. When weighted, Fragile Families is representative of all births in US cities with populations over 200 000. Results: Children of mothers with intellectual impairments had poorer behavioural and cognitive outcomes in comparison to same-age children of mothers without intellectual impairments. Notably, however, children of mothers with intellectual impairments were not at increased risk of being aggressive unless their family income was below 200% of the federal poverty level. Further, families headed by mothers with intellectual impairments experienced multiple hardships related to socioeconomic factors, limited social supports and poor self-reported health. Conclusion: Appropriate policies and programmes must be developed and implemented to effectively support these families, such as increased financial benefits.

Author(s): J. Kingslake [sup.1] , R. P. Scherer [sup.2] , T. Albrecht [sup.3] , J. Coenen [sup.2] , R. D. Powell [sup.2] , R. Reese [sup.3] , N. D. Stansell [...], To predict the future contributions of the Antarctic ice sheets to sea-level rise, numerical models use reconstructions of past ice-sheet retreat after the Last Glacial Maximum to tune model parameters.sup.1. Reconstructions of the West Antarctic Ice Sheet have assumed that it retreated progressively throughout the Holocene epoch (the past 11,500 years or so).sup.2-4. Here we show, however, that over this period the grounding line of the West Antarctic Ice Sheet (which marks the point at which it is no longer in contact with the ground and becomes a floating ice shelf) retreated several hundred kilometres inland of today's grounding line, before isostatic rebound caused it to re-advance to its present position. Our evidence includes, first, radiocarbon dating of sediment cores recovered from beneath the ice streams of the Ross Sea sector, indicating widespread Holocene marine exposure; and second, ice-penetrating radar observations of englacial structure in the Weddell Sea sector, indicating ice-shelf grounding. We explore the implications of these findings with an ice-sheet model. Modelled re-advance of the grounding line in the Holocene requires ice-shelf grounding caused by isostatic rebound. Our findings overturn the assumption of progressive retreat of the grounding line during the Holocene in West Antarctica, and corroborate previous suggestions of ice-sheet re-advance.sup.5. Rebound-driven stabilizing processes were apparently able to halt and reverse climate-initiated ice loss. Whether these processes can reverse present-day ice loss.sup.6 on millennial timescales will depend on bedrock topography and mantle viscosity--parameters that are difficult to measure and to incorporate into ice-sheet models.Radiocarbon dating of sediment cores and ice-penetrating radar observations are used to demonstrate that the West Antarctic Ice Sheet has not retreated progressively during the Holocene epoch, but has instead showed periods of retreat and re-advance.

The ability to distinguish peatland types at the landscape scale has implications for inventory, conservation, estimation of carbon storage, fuel loading, and postfire carbon emissions, among others. This paper presents a multisensor, multiseason remote sensing approach to delineate boreal peatland types (wooded bog, open fen, shrubby fen, treed fen) using a combination of multiple dates of L-band (24 cm) synthetic aperture radar (SAR) from ALOS PALSAR, C-band (~5.6 cm) from ERS-1 or ERS-2, and Landsat 5 TM optical remote sensing data. Imagery was first evaluated over a small test area of boreal Alberta, Canada, to determine the feasibility of using multisensor SAR and optical data to discriminate peatland types. Then object-based and (or) machine-learning classification algorithms were applied to 3.4 million ha of peatland-rich subregions of Alberta, Canada, and the 4.24 million ha region of Michigan's Upper Peninsula where peatlands are less dominant. Accuracy assessments based on field-sampled sites show high overall map accuracies (93%-94% for Alberta and Michigan), which exceed those of previous mapping efforts. Key words: peatlands, fens, bogs, boreal, synthetic aperture radar, SAR, Landsat, PALSAR, ERS-2, Random Forests, mapping. La capacite de distinguer les types de tourbieres a l'echelle du paysage a des repercussions notamment sur l'inventaire, la conservation, l'estimation de la sequestration du carbone, la charge de combustible et les emissions de carbone apres un feu. Cet article presente une approche de teledetection multi-capteur et multi-saison pour delimiter les differents types de tourbieres boreales (tourbieres ombrotrophes boisees, tourbieres minerotrophes ouvertes, arbustives ou arborees) a l'aide d'une combinaison de donnees de teledetection multi-temporelles du radar a synthese d'ouverture (SAR) en bande L (24 cm) du satellite ALOS PALSAR et en bande C (~5,6 cm) du satellite ERS-1 ou ERS-2 ainsi que de donnees optiques du satellite Landsat 5 TM. L'imagerie a d'abord ete evaluee sur une superficie experimentale limitee dans le nord de l'Alberta, au Canada, pour determiner la faisabilite d'utiliser le SAR multi-capteur et des donnees optiques pour distinguer les types de tourbieres. Ensuite, des algorithmes de classification fondes sur les objets ou l'apprentissage automatique ont ete appliques a 3,4 millions ha de sous-regions de l'Alberta, au Canada, riches en tourbieres et a la region de 4,24 millions ha de la peninsule superieure du Michigan ou les tourbieres sont moins dominantes. Les evaluations de la precision fondees sur les sites echantillonnes au sol montrent des precisions cartographiques globales elevees (93-94 % pour l'Alberta et le Michigan) qui depassent celles des essais anterieurs de cartographies. [Traduit par la Redaction] Mots-cles: tourbieres, tourbieres minerotrophes, tourbieres ombrotrophes, boreal, radar a synthese d'ouverture, (SAR), Landsat, PALSAR, ERS-2, forets aleatoires, cartographie., Introduction Peatlands are defined as having saturated soils, anaerobic conditions, and large accumulations of partially decomposed organic plant material (peat) below the ground. This accumulation is a result of low [...]