Paragenesis of unusual Fe-cordierite (sekaninaite)-bearing paralava and clinker from the Kuznetsk coal basin,Siberia, Russia

Sekaninaite (X_Fe > 0.5)-bearing paralava and clinker are the products of ancient combustion metamorphism in the western part of the Kuznetsk coal basin, Siberia. The combustion metamorphic rocks typically occur as clinker beds and breccias consisting of vitrified sandstone–siltstone clinker fragments cemented by paralava, resulting from hanging-wall collapse above burning coal seams and quenching. Sekaninaite–Fe-cordierite (X_Fe = 95–45) is associated with tridymite, fayalite, magnetite, ± clinoferrosilite and ±mullite in paralava and with tridymite and mullite in clinker. Unmelted grains of detrital quartz occur in both rocks (<3 vol% in paralavas and up to 30 vol% in some clinkers). Compositionally variable siliceous, K-rich peraluminous glass is <30% in paralavas and up to 85% in clinkers. The paralavas resulted from extensive fusion of sandstone–siltstone (clinker), and sideritic/Fe-hydroxide material contained within them, with the proportion of clastic sediments ≫ ferruginous component. Calculated dry liquidus temperatures of the paralavas are 1,120–1,050°C and 920–1,050°C for clinkers, with calculated viscosities at liquidus temperatures of 10^1.6–7.0 and 10^7.0–9.8 Pa s, respectively. Dry liquidus temperatures of glass compositions range between 920 and 1,120°C (paralava) and 920–960°C (clinker), and viscosities at these temperatures are 10^9.7–5.5 and 10^8.8–9.7 Pa s, respectively. Compared with worldwide occurrences of cordierite–sekaninaite in pyrometamorphic rocks, sekaninaite occurs in rocks with X_Fe (mol% FeO/(FeO + MgO)) > 0.8; sekaninaite and Fe-cordierite occur in rocks with X_Fe 0.6–0.8, and cordierite (X_Fe < 0.5) is restricted to rocks with X_Fe < 0.6. The crystal-chemical formula of an anhydrous sekaninaite based on the refined structure is | \textK_0.02 |(\textFe_1.54^{2 +} \textMg_0.40 \textMn_0.06 )_{\Upsigma 2.00}^M [(\textAl_1.98 \textFe_0.02^{2 +} \textSi_1.00 )_{\Upsigma 3.00}^T1 (\textSi_3.94 \textAl_2.04 \textFe_0.02^{2 +} )_{\Upsigma 6.00}^T2 \textO₁₈ ]. \left| {{\text{K}}_{0.02} } \right|({\text{Fe}}_{1.54}^{2 + } {\text{Mg}}_{0.40} {\text{Mn}}_{0.06} )_{\Upsigma 2.00}^{M} [({\text{Al}}_{1.98} {\text{Fe}}_{0.02}^{2 + } {\text{Si}}_{1.00} )_{\Upsigma 3.00}^{T1} ({\text{Si}}_{3.94} {\text{Al}}_{2.04} {\text{Fe}}_{0.02}^{2 + } )_{\Upsigma 6.00}^{T2} {\text{O}}_{18} ].     

Vulnerability and its discontents: the past,present, and future of climate change vulnerability research

The agri-food sector must adapt to changes in climate variability, while also helping to mitigate climate change. Measures termed ‘triple-win’ mitigate and adapt to climate change, while also improving soil health, thereby increasing yields. These measures might appear to be the easiest to implement, but in practice, barriers prevent full realisation. This study aims to move beyond previous research efforts that identify and categorise barriers by (i) revealing hidden barriers, (ii) understanding the interactions between barriers and (iii) exploring ways to address barriers. A case study focusing on crop rotation as a triple-win strategy in Ukraine demonstrates how a participant-driven iterative research approach can achieve these objectives. During semi-structured interviews with farmers and stakeholders, crop rotation emerged as an area of considerable dissensus with stakeholders commonly citing the greedy behaviour of producers as the problem. Further discussion indicated that the political economy of Ukraine caused financial constraints for producers and Q methodology allowed for additional clarity on the opposing views of crop rotation. Three factors emerged: producer insecurity, national insecurity and business insecurity. These three perspectives reveal contrasting priorities with producer insecurity and business insecurity concerned with the conditions under which producers must operate, while national insecurity has a focus on improving agricultural production to benefit the nation. Consensus statements across all factors could provide first steps to addressing barriers and an opportunity to open discussions amongst stakeholders. Finally, barriers arising from political processes demonstrate that climate policy needs to be integrated with other sector-specific policy decisions.     

Barriers to movement: Modelling energetic costs of avoiding marine wind farms amongst breeding seabirds

Proposals for wind farms in areas of known importance for breeding seabirds highlight the need to understand the impacts of these structures. Using an energetic modelling approach, we examine the effects of wind farms as barriers to movement on seabirds of differing morphology. Additional costs, expressed in relation to typical daily energetic expenditures, were highest per unit flight for seabirds with high wing loadings, such as cormorants. Taking species-specific differences into account, costs were relatively higher in terns, due to the high daily frequency of foraging flights. For all species, costs of extra flight to avoid a wind farm appear much less than those imposed by low food abundance or adverse weather, although such costs will be additive to these. We conclude that adopting a species-specific approach is essential when assessing the impacts of wind farms on breeding seabird populations, to fully anticipate the effects of avoidance flights.     

Evaluation ofCitrullus colocynthis, a desert plant native in Israel, as a potential source of edible oil

Citrulus colocynthis(wild gourd) is a desert plant of the Cucurbitaceae, naturally adapted to arid environments. It was known in biblical times as a source of seed oil and its fruits were used as an efficient laxative. Accessions were collected in Israel and evaluated as a potential oil seed crop adapted to arid zones. It was found that its oil composition is similar to safflower oil, with a total of 80-85% unsaturated fatty acids. A potential yield of oil of 250-400 l ha⁻¹was calculated. The best yield was obtained during the first 4 weeks of the 10-week maturation period. Yield potential should be estimated under desert conditions in order to evaluate the plant's economic future as a crop suitable for an arid environment.     

A note on magnetic modelling with remanence

The general problem of magnetic modelling involves accounting for the effect of both remanent magnetization and the application of an external magnetic field. However, as far as the disturbing field of a magnetic body in a magnetic environment is concerned, there is an equivalence between the effects of these two causations that allows the remanence to be represented in terms of an equivalent primary magnetic H field. Moreover, due to the linearity of the magnetic field in terms of its causations, the general modelling problem involving an applied magnetic field in the presence of remanence can be simply and more efficiently dealt with in terms of an equivalent primary field acting in the absence of any remanent magnetization.     

Horashim East: a newly discovered Middle Palaeolithic site in central Israel

Horashim East is a newly discovered Middle Palaeolithic open-air occurrence in central Israel, revealed during a thematic prehistoric survey. Hundreds of lithic items were found, including an early-stage biface, Levallois cores and products. As only a few open-air settlements are known from the Middle Palaeolithic Levant, the discovery of Horashim East sheds new light on human land-use patterns during this period and reinforces the notion that central-eastern Israel was favourable for human settlement throughout the Palaeolithic.     

Modelling the effect of land management interventions and climate change on sediment loads in the Manawatū–Whanganui region

ABSTRACT

SedNetNZ is used to model the effect of erosion control undertaken under the Sustainable Land Use Initiative (SLUI) and predict the effect of climate change on sediment load in the Manawatū–Whanganui region. Sediment load in 2004 is estimated at 13.4?Mt?yr^?1; by 2018, ≈5000?km² of land had farm plans implemented and annual sediment load reduced by 6.2% of the 2004 load. If SLUI stops at the 2018 level of implementation, by 2038 it is predicted to achieve a 15.7% reduction in annual sediment load. If SLUI continues to implement farm plans, 7949?km² of land will be treated by 2043 and annual sediment load could be reduced by a further 14.7%. Climate change is predicted to substantially increase sediment loads. By 2043 annual sediment load for the region is predicted to increase, compared to 2004, by between 8.3 and 23.7%. However, this can largely be offset by SLUI works. By 2090 an annual sediment load increase of between 53 and 224% due to climate change is predicted. The results suggest climate warming may dominate changes in sediment load in the future.     

Effects of Animal Size on Concentrations of Metallothionein and Metals in Periwinkles Littorina littorea Collected from the Firth of Clyde, Scotland

Different sizes of Littorina littorea were collected from four areas in the Firth of Clyde, Scotland. Their metallothionein (MT) and heavy metal concentrations were analysed using the Silver Saturation Method and Atomic Absorption Spectrophotometry, respectively. Concentrations of MT, Cd and Zn (as μg g⁻¹ dry soft-body weight) generally decreased with an increase in size of L. littorea. MT concentrations were better correlated with Cd than with Zn or Cu concentrations. Nevertheless, MT and the metals in periwinkles (as μg individual⁻¹) increased significantly with increasing size. Concentrations of MT and the metals among the sampling areas were compared at a standardised soft-body weight (10 mg). The results from Discriminant Analysis based on all metal concentrations indicate that Largs is different from the other areas and characterised by high Fe concentrations in L. littorea. The problems and differences in using either soft-body weight or shell length as independent variable for size-standardisation are discussed.