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Do conservation covenants consider the delivery of ecosystem services?
No full textPrivately protected areas promote the conservation of biodiversity and have also been shown to conserve valuable ecosystem services. Legally binding instruments like conservation covenants are important mechanisms to protect the natural environment on private land. However, the extent to which conservation covenants either explicitly require or allow for the delivery of ecosystem services, and the specific ways through which they achieve this, are largely unexplored. We undertook a content analysis of clauses in individual covenant documents, overarching legislative, and policy frameworks to examine this issue. We use a qualitative coding framework to assess how clauses consider the supply and the flow of ecosystem services to covenantors and society. We found that the requirements of conservation covenants did not widely consider the management ecosystem services. When covenant clauses focused on ecosystem services, they primarily considered the flow of ecosystem services between areas of supply to areas of demand. Clauses primarily considered these ecosystem services flows to the covenantor, with only a small number of clauses explicitly considering to ecosystem services flows to society more broadly. Finally, we found that regulating services, like erosion prevention, were often positively associated with conservation covenants, whereas cultural and provisioning services, like nature-based recreation, were often negatively associated with conservation covenants. Understanding how conservation covenants consider the delivery of ecosystem services is important if privately protected areas are to both conserve biodiversity and promote ecosystem services co-benefits
Biochemical changes and distribution of nitrogen from bands of stabilised N-fertilizers in contrasting soils
No full text'Stabilised' nitrogen (N) represents an important category of enhanced efficiency fertilizers (EEFs) in which chemicals added to urea granules inhibit target soil N transformation processes in order to optimize N availability for crop uptake. However the mechanistic understanding of how these inhibitors perform when urea-based fertilizers are banded, causing substantial modifications to the soil chemical environment, is poorly understood. In a 16-day laboratory incubation, the efficacies of the nitrification inhibitor (NI), 3,4-dimethylpyrazole phosphate (DMPP), and the urease inhibitor (UI), N-(n-butyl) thiophosphoric triamide (NBPT), were investigated in two soils by incubating two commercially available urea-based products containing these additives in bands at concentrations equivalent to 150 kg N ha(-1) at row spacing of 1.8 m. When compared to a granular urea standard, DMPP did not provide any inhibitory benefits except when the inhibitor was able to diffuse beyond the zone affected by urea-N hydrolysis, within which considerable nitrification inhibition occurred because of the chemical conditions. The benefit of the NI was most significant in the soil with higher clay, organic matter and pH buffering capacity, with these properties confining the ureolytic-induced chemical changes and N transformations inhibitory zone closer to the fertilizer band. In contrast, the UI provided some benefit by slowing the rapid rise in pH, electrical conductivity and aqueous ammonia observed in standard urea bands, although the effects of NBPT were temporary (ca. 9 days) in both soils. The benefit of NI and UI technology relative to urea alone is likely to vary considerably between soils and fertilizer application methods. This study provides a physico-chemical approach to determining under what conditions the benefits of banded 'stabilising' EEF technology may be realised
Sulfophilic and lithophilic sites in bimetal nickel-zinc carbide with fast conversion of polysulfides for high-rate Li-S battery
No full textThe notorious shuttle effect and slow reaction kinetics of lithium polysulfides (LiPSs) severely limit the cycle stability and rate performance of lithium sulfur (Li-S) batteries. Herein, we demonstrated that the issue of shuttling effect of LiPSs could be effectively addressed by using a separator coating based on NiZnC bimetal carbide nanoparticles dispersed in nitrogen-doped porous carbon material matrix containing small amount of Ni metal particles, namely NiZnC/Ni/NCNTs. When used as a separator coating of Li-S cells, the NiZnC bimetal carbides demonstrated efficient adsorption and catalytic effect towards LiPSs, inhibiting the shuttle effect and enhancing the electrochemical performance of device. The Li-S cell still maintained excellent charging and discharging platform even at a high rate of 7C. Theoretical calculation shows that, compared to the monometal carbide NiC, the bimetal carbide NiZnC possesses the advantageous properties of both sulfophilic sites of Ni and lithophilic sites of Zn, resulting in reduced energy barriers for lithium ion diffusion and improved catalytic capability, thus enhancing reaction kinetics of LiPSs. This work paves a new way to resolving the critical issues of shuttle effect, cycle stability and rate capability of Li-S batteries by taking advantage of synergistic effect of Ni and Zn in the bimetal carbide
The legacy and drivers of groundwater nutrients and pesticides in an agriculturally impacted Quaternary aquifer system
No full textNutrient and pesticide pollution are among the major threats to groundwater quality in agriculturally impacted aquifers. Understanding their legacy effects and drivers are important to protect aquifers from exposures to contamination. However, the complexities of groundwater flowpaths make it difficult to predict the time-scales of groundwater flow and contaminant transport. To determine these controls of groundwater nutrient and pesticides in an aquifer system underlying an intensive agricultural area in the Great Barrier Reef catchment, Australia, we sampled tritium (3H) to estimate groundwater-age, nutrient and pesticide concentrations to investigate groundwater contamination, and nitrogen (ẟ15N-NO3−) and oxygen (ẟ18O-NO3−) isotopes to determine groundwater nitrate dynamics. We, then, constructed high-resolution 3D geological and groundwater flow models of the aquifer system to determine the role of the geologic heterogeneity on the observed nutrient and pesticide concentrations. Groundwater\ua03H derived ages, and nutrient and pesticide concentrations did not follow distinct spatial trends. ẟ15N-NO3−\ua0and ẟ18O-NO3−\ua0values indicated that nitrification and denitrification processes influenced nitrate dynamics in the aquifer system; however, they were not solely able to explain the entire 3D variability. The 3D geologic modelling identified possible preferential flowpaths and perched systems, which helped to explain the observed groundwater-age, nutrient and pesticide variabilities. Old-groundwater (~100-years) was found in shallow depths (25\ua0m), below perched and locally confined systems. Downward increasing groundwater-age, and decreasing nutrient and pesticide concentrations were detected in the unconfined aquifer, while old-groundwater (~160-years) and lower nitrate
On formulations of skew factor models: Skew factors and/or skew errors
No full textIn recent years, several mixtures of skew factor analyzers have been proposed. These models adopt various skew distributions for either the factors or the errors, but not both. This paper examines the connections between these formulations and introduces a unified model that allows for skewness in both the factors and errors
Microporous nickel phosphonate derived heteroatom doped nickel oxide and nickel phosphide: Efficient electrocatalysts for oxygen evolution reaction
No full textDesigning low-cost and highly efficient electrocatalysts based on widely abundant elements is highly desirable for future green energy production. Transition metal oxides and phosphides have recently been demonstrated to be promising and cost-effective electrocatalysts due to their distinct surface properties and good conductivity. Herein, we have synthesized a new microporous organic-inorganic hybrid nickel phosphonate (NiPPA) material under hydrothermal reaction condition without the use of structure directing agent. The microporous NiPPA material can be converted to N, P-codoped nickel oxide (NP/NiO) and N, O-codoped nickel phosphide (NO/NiP) following pyrolysis under air and nitrogen atmospheres, respectively. These high surface area materials are subsequently explored as electrocatalysts towards oxygen evolution reaction (OER) in alkaline media. Among the three catalysts, NP/NiO exhibits the highest electrocatalytic activity for OER with an overpotential of 332 mV to reach a current density of 10 mA cm and a low Tafel slope of 65.6 mV dec in 1.0 M KOH solution. Furthermore, the as-prepared NP/NiO catalyst displays an outstanding stability over a period of 15 h, suggesting the high durability of this catalyst for OER
Achieving high ductility in a selectively laser melted commercial pure-titanium via in-situ grain refinement
No full textGrain refinement of additively manufactured titanium and titanium alloys can be promoted via adding foreign elements or particles, but it may lead to a reduction in ductility due to the formation of brittle intermetallic compounds. The present study shows that in-situ grain refinement of commercially pure titanium (CP-Ti) can be achieved through properly controlling the selective laser melting (SLM) parameters. It was found that higher input energy density worked in favour of grain refinement. Detailed microstructural characterization coupled with multi-physics simulation were performed to reveal the grain refinement mechanism. This was attributed to the intrinsic heat treatment (IHT) effect which resulted from the cyclic reheating inherent to the SLM process. As a result, the refined CP-Ti exhibited an exceptionally high ductility of 34.3 ±\ua00.5% without notable mechanical anisotropy. This work demonstrates the feasibility of utilizing thermal cycling of additive manufacturing (AM) to refine grains of metals without changing the composition
Exploring climate-driven non-economic loss and damage in the Pacific Islands
No full textNon-economic loss and damage induced by climate change in the Pacific Islands region has been reported as fears of cultural loss, deterioration of vital ecosystem services, and dislocation from ancestral lands, among others. This paper undertakes an in-depth systematic review of literature from the frontlines of the Pacific Islands to ascertain the complexities of non-economic loss and damage from climate change. We synthesise knowledge to date on different but inter-connected categories of non-economic loss and damage, namely: human mobility and territory, cultural heritage and Indigenous knowledge, life and health, biodiversity and ecosystem services, and sense of place and social cohesion. Identifying gaps and possibilities for future research agendas is presented. Synthesising knowledge to date and identifying remaining gaps about non-economic loss and damage is an important step in taking stock of what we already know and fostering action and support for addressing loss and damage in the years to come
Association of maternal ozone exposure with term low birth weight and susceptible window identification
No full textBackgroundOzone pollution keeps deteriorating in the context of climate change. Maternal ozone exposure may be associated with low birth weight (LBW), but the results are still inconsistent. The identification of the critical exposure windows, a specific period of particular susceptibility during pregnancy, remains unresolved. We aimed to evaluate whether ozone exposure was associated with term LBW and further identify the susceptible exposure windows.MethodsA retrospective cohort study was conducted in Guangzhou, a megacity in the most populous and economically developed city clusters in China. We included 444,096 singleton live births between January 2015 and July 2017. From 11 fixed stations, we collected daily 1-h maximum and 8-h maximum moving average ozone level (O3-1\ua0h and O3-8\ua0h) and calculated exposures for each participant based on their district of residence during pregnancy. We used traditional Logistic regression to estimate the trimester-specific association between ozone exposure and term LBW, and further estimated monthly- and weekly association by distributed lag models (DLMs) with Logistic regression. Odds ratios (ORs) and 95% confidence intervals (CIs) of term LBW were calculated for an interquartile range (IQR) increase in ozone exposure. Stratified analyses and heterogeneity tests were conducted by maternal age and infant sex.ResultsThe incidence of term LBW was 1.9%. During the study period, the mean O3-1\ua0h and O3-8\ua0h levels were 112.6\ua0µg/m3\ua0and 84.5\ua0µg/m3, respectively. Increased O3-1\ua0h (IQR: 90\ua0µg/m3) and O3-8\ua0h (73\ua0µg/m3) exposure during the second trimester were associated with increased risk of term LBW. At a monthly level, the term LBW risk was associated with O3-1\ua0h exposure during the 4th-6th month and O3-8\ua0h exposure during the 6th month. By estimating the weekly-specific association, we observed that critical exposure windows were the 15th- 26th gestational weeks for O3-1\ua0h, and the 20th-26th weeks for O3-8\ua0h, respectively. Estimated ORs and 95% CIs ranged from 1.012 (1.000, 1.024) to 1.023 (1.007, 1.039). When examined by subgroups, the effects were present among women\ua0≥\ua035\ua0years or\ua
Alternative entry points for adaptation: examples from Vanuatu
No full textAs climate change accelerates, effective adaptation is an urgent and unavoidable priority. Bottom-up approaches such as community-based adaptation have been portrayed as the panacea. Recent studies are, however, highlighting the ongoing and inherent issues with normative “community” conceptualizations that assume a geographically bound, temporally fixed, and harmonious unit. Despite documentation on the negative impact these problematic assumptions can have on adaptation outcomes, adaptation at the community scale remains the preferred option for project delivery in highly exposed places such as the Pacific Islands region. More creative entry points that are less charged with problematic assumptions are needed at the local scale. This paper draws from three examples in Vanuatu to offer compelling alternative entry points for adaptation: 1) a rural technical college embedded within an Anglican mission village, 2) a whole-of-island approach, and 3) the “collective of vendors” at marketplaces. We offer hope by identifying ways to expand on and complement existing, restricted notions of community and, through this, to improve adaptation outcomes
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