Warm Water Research Articles

Dense Water Production in Storfjorden, Svalbard, From a 1‐Year Time Series of Observations and a Simple Model: Are Polynyas in a Warming Arctic Exporting Heat to the Deep Ocean?

AbstractThe formation of dense Brine‐enriched Shelf Water (BSW) in Storfjorden is analyzed during Winter 2016–2017 from mooring observations, a polynya model nudged to satellite observations, and an original BSW production model. The ice season was two months shorter than average, yet 44.2 of sea ice were formed, in line with estimates for the period preceding the atlantification of the Barents Sea in the mid‐2000s: A thinner, more fragile ice may favor polynya openings and frazil ice production. A saline specimen of BSW was produced in large volumes, corresponding to an annual mean transport of 0.042 Sv, larger than previous estimates. The important production is due to the preconditioning of the polynya with a more saline source water, exceeding the pre‐2005 values by 0.37. The BSW overflow was observed on the West Spitsbergen shelf slope from hydrographic sections down to 750 m, thus entering the Norwegian Sea Deep Water layer. Its core temperature was about C warmer than the pre‐2005 values owing to the entrainment of a warmer water in Storfjordrenna, suggesting that a part of the excess surface heat of the Barents Sea could be exported into the deep ocean. Overall our results suggest that dense water formation in the Storfjorden polynya may not, at least for now, be hampered by the atlantification of the Barents Sea, and perhaps even temporarily favored by the more saline source water. Anomalous atmospheric warming during the Winter‐Spring may however disrupt the production, as was observed 1 year before.

Precession‐Driven Variations in the Indonesian Throughflow Thermocline and Its Implications on the Agulhas Leakage

AbstractThe Indonesian Throughflow (ITF) thermocline, as exclusive water source for the “warm water route” of the Atlantic Meridional Overturning Circulation (AMOC), provides waters that exit the Indian Ocean and join the AMOC upper limb via the Agulhas Leakage (AL). Hence, investigating long‐term variations in the ITF thermocline and its implications on the AL is important for understanding dynamics of the AMOC. Here, the thermohaline history of the ITF thermocline was reconstructed for the last ∼410 kyr based on δ18O and Mg/Ca of planktonic foraminifera from International Ocean Discovery Program Site U1483. By integrating the new and published records, we found that precession drives variation of the ITF thermocline through modulating the intensity of the Australian‐Indonesian winter monsoon, El Niño‐Southern Oscillation‐like states and formation of the North Pacific Tropical Water, in turn exerting a transoceanic influence on the amount of the AL and seawater temperature and salinity of the South Atlantic thermocline.

Future increase in extreme El Niño supported by past glacial changes

El Niño events, the warm phase of the El Niño–Southern Oscillation (ENSO) phenomenon, amplify climate variability throughout the world1. Uncertain climate model predictions limit our ability to assess whether these climatic events could become more extreme under anthropogenic greenhouse warming2. Palaeoclimate records provide estimates of past changes, but it is unclear if they can constrain mechanisms underlying future predictions3–5. Here we uncover a mechanism using numerical simulations that drives consistent changes in response to past and future forcings, allowing model validation against palaeoclimate data. The simulated mechanism is consistent with the dynamics of observed extreme El Niño events, which develop when western Pacific warm pool waters expand rapidly eastwards because of strongly coupled ocean currents and winds6,7. These coupled interactions weaken under glacial conditions because of a deeper mixed layer driven by a stronger Walker circulation. The resulting decrease in ENSO variability and extreme El Niño occurrence is supported by a series of tropical Pacific palaeoceanographic records showing reduced glacial temperature variability within key ENSO-sensitive oceanic regions, including new data from the central equatorial Pacific. The model–data agreement on past variability, together with the consistent mechanism across climatic states, supports the prediction of a shallower mixed layer and weaker Walker circulation driving more frequent extreme El Niño genesis under greenhouse warming.

Bacterioplankton of the Western Part of the Kara Sea

Data on the structural and production characteristics of bacterioplankton in the western part of the Kara Sea at the beginning and in the middle of summer are presented. In the region of the St. Anna Trough slope, the average abundance of prokaryotes for the water column was (594–708) × 103 cells/ml (26.4–36.5 mgC/m3) in June and (247–517) × 103 cells/ml (12–28 mgC/m3) at the beginning of August. On the transect along Novaya Zemlya, the average abundance of bacterioplankton in the water column was (186–554) × 103 cells/mL (8.5–30 mgC/m3) within a week after the seasonal ice and (169–443) × 103 cells/mL (8–21 mgC/m3) in the midsummer. Bacterial specific growth rate did not exceed 1.28 day–1; its high values were observed in the upper warm water layer, above the halocline, and also at the near-bottom depths. At the beginning of summer, the production of bacterioplankton tended to decrease in the northeast direction. The distribution of prokaryotes abundance was determined by temperature and water saturation with oxygen, possibly as an indirect indicator of past phytoplankton “bloom”.

Altimeter-derived poleward Lagrangian pathways in the California Current System: Part 1

We use altimeter-derived geostrophic velocities, with and without the addition of surface Ekman transports, to create trajectories for virtual parcels in the California Current System (CCS). The goal is to investigate the poleward transport of passive water parcels in the surface 50–100 m of the nominally equatorward system. Motivation for the study is provided by observations of anomalous biomass of copepods with warm water affinities along the Newport Hydrographic Line off central Oregon (44.7°N) during El Niño years, as well as during and following the 2014–2016 marine heat wave. By backward tracking virtual parcels from 44.7°N, we find that the most distant source of passive water parcels in the upper ocean during a one-year period of travel is from within the Southern California Bight (SCB), north of 30°N. To make that journey, parcels use the Inshore Countercurrent off southern and central California during summer–winter and the Davidson Current off northern California and Oregon during autumn–winter. The inclusion of small-scale eddy diffusion usually increases the number of parcels that reach more northern latitudes, while the inclusion of Ekman velocities more often reduces those numbers. Even so, parcels can travel from the SCB to central Oregon in either the Ekman layer or beneath it in the geostrophic flow. Using backward tracking, we find that parcels arrive at 44.7°N most often in winter–spring, least often in autumn. They arrive from within the large-cape region off northern California (41°–42°N) during all years and all months, from just south of the large-cape region (38°–39°N) during most years but seldom in autumn, from south of Monterey Bay along central California (36°N) and within the SCB (34.5°N) during a third (or less) of the years and only in winter-spring. The shortest average transit times are found in winter: for parcels reaching 44.7°N in February, the average transit time is 2 months for parcels coming from 41°–42°N, 4 months for parcels coming from 38°–39°N, and 5–6 months or more for parcels coming from south of 36°N. Transit times increase as the arrival time progresses from winter to autumn. The longest average transit times are for parcels reaching central Oregon in autumn (9–12 months in October for parcels coming from south of 39°N). This makes the journey a multi-generational task for the copepods. Interannual variability in the observed southern copepod species biomass off central Oregon correlates highly with years when more virtual parcels from the south reach central and northern Oregon, providing increased confidence in the results found with the altimeter-derived parcel trajectories.

Non-invasive methods characterise the world’s largest tiger shark aggregation in Fuvahmulah, Maldives

Tiger sharks are apex predators with a circumglobal tropical and warm-temperate distribution, with a general lack of population data for the central Indian Ocean. In Fuvahmulah, Maldives, tiger sharks display frequent use of the harbour area, attracted by discarded fish waste. Here, we document the population structure, residency, and reproductive characteristics of the world’s largest known tiger shark aggregation in a geographically-restricted area. Using non-invasive methods, photo identification and laser photogrammetry, we identified 239 individual tiger sharks over a 7-year study period. The aggregation was female-dominated (84.5%), with both large juveniles and adults present. Adult females were resighted over the entire study period displaying strong inter- and intra-annual site fidelity. Modelled residency using maximum likelihood methods suggests they spent 60.7 ± S.E. 7.5 days in Fuvahmulah, with a larger aggregation size, shorter residence periods and longer absence periods compared to juvenile females. Prolonged abdominal distensions of adult females indicate they likely stay near Fuvahmulah during gestation and reproduce biennially. Fuvahmulah seems to provide suitable conditions for gestation given the year-round provision of food and warm waters, exhibited by strong site fidelity and temporal residency. Our results show indications of a thriving population within the confines of protected waters.

Changes in biogeographic patterns of coastal benthic decapods: Indicators of tropicalization in the Canary Islands over the last 50 years

The Canary Islands constitute one of the major marine biodiversity hotspots in the eastern-central Atlantic, with decapod crustaceans being a highly representative group in the benthic environment due to their vast diversity of taxa and occupied ecosystems. This study identifies three significant milestones corresponding to the publication of comprehensive decapod checklist for the Canary Islands in 1973, 1995, and 2018. The lists of coastal benthic decapod species (0–300 m depth) were revised and updated, indicating the biogeographic pattern and vertical distribution range of each species in the region. Changes in the composition of the biogeographic patterns of coastal decapods in the Canary Islands were analysed to evaluate whether they could be considered as a useful indicator of the tropicalization process in the region. Particular attention was paid to variations in the percentages of species with warm water affinity versus those with Atlanto-Mediterranean preferences, with the former showing a clear upward trend.

Effect of pre-sowing treatments on seed germination and postgerminative seedling growth of acacia angustissima (mill.)

Seeds of Acacia angustissima were subjected to a control and five pre-sowing (soaking in cold water for 24 hours, soaking in hot water (100° C) for 5 minutes, immersion in 60 % H2SO4 for 30 seconds, immersion in 60 % H2SO4 for 5 minutes, and immersion in 60 % H2SO4 for 15 minutes) treatments. The number of seeds that sprouted was recorded daily for calculation of germination indices. When there had been no further germination in any of the treatments for four weeks, the height, number of leaves, number of leaflets, and root length of seedlings were determined. One-way analysis of variance was used to test the effects of the pre-sowing treatments on seed germination and seedling growth. Final Germination Percentage, Germination Rate Index, and Seedling Vigour Index were significantly higher in the warm water than other five treatments which displayed similar responses of the traits. Similar, the warm water pre-treatment resulted in the longest seedlings, when shoot height and / or root length was considered. There was no significant effect of treatment on Mean Germination Time, number of leaves, and number of leaflets. The findings suggest that hot water pre-sowing treatment is the most suitable for seed germination and initial seedling height attainment of Acacia angustissima.

Effect of pre-sowing treatments on seed germination and postgerminative seedling growth of acacia angustissima (mill.)

Seeds of Acacia angustissima were subjected to a control and five pre-sowing (soaking in cold water for 24 hours, soaking in hot water (100° C) for 5 minutes, immersion in 60 % H2SO4 for 30 seconds, immersion in 60 % H2SO4 for 5 minutes, and immersion in 60 % H2SO4 for 15 minutes) treatments. The number of seeds that sprouted was recorded daily for calculation of germination indices. When there had been no further germination in any of the treatments for four weeks, the height, number of leaves, number of leaflets, and root length of seedlings were determined. One-way analysis of variance was used to test the effects of the pre-sowing treatments on seed germination and seedling growth. Final Germination Percentage, Germination Rate Index, and Seedling Vigour Index were significantly higher in the warm water than other five treatments which displayed similar responses of the traits. Similar, the warm water pre-treatment resulted in the longest seedlings, when shoot height and / or root length was considered. There was no significant effect of treatment on Mean Germination Time, number of leaves, and number of leaflets. The findings suggest that hot water pre-sowing treatment is the most suitable for seed germination and initial seedling height attainment of Acacia angustissima.

Enhanced ocean heat storage efficiency during the last deglaciation

Proxy reconstructions suggest that increasing global mean sea surface temperature (GMSST) during the last deglaciation was accompanied by a comparable or greater increase in global mean ocean temperature (GMOT), corresponding to a large heat storage efficiency (HSE; ∆GMOT/∆GMSST). An increased GMOT is commonly attributed to surface warming at sites of deepwater formation, but winter sea ice covered much of these source areas during the last deglaciation, which would imply an HSE much less than 1. Here, we use climate model simulations and proxy-based reconstructions of ocean temperature changes to show that an increased deglacial HSE is achieved by warming of intermediate-depth waters forced by mid-latitude surface warming in response to greenhouse gas and ice sheet forcing as well as by reduced Atlantic meridional overturning circulation associated with meltwater forcing. These results, which highlight the role of surface warming and oceanic circulation changes, have implications for our understanding of long-term ocean heat storage change.

Extraction and characterisation of gelatine from yellowfin tuna skin pretreated with a eutectic solvent

The accumulation and management of waste generated during the processing of seafood products is one of the major current challenges in the fishery industry. Among these residues, fish skin stands out for its high collagen content, from which high-quality gelatine can be obtained. However, conventional methods for gelatine extraction are time-consuming and complex processes that involve the use of strong acidic and alkaline solutions, leading to serious environmental concerns. This research studied the use of a eutectic solvent, formed by two safe and environmentally friendly compounds such as sodium acetate trihydrate and urea, to pretreat the skin of yellowfin tuna before the extraction of gelatine. Two different times of pretreatment were tested, and the subsequent extraction was carried out in warm water, resulting in much higher yields of gelatine (0.3 g/g wet fish skin) than previous studies. Additionally, using FT-IR analysis and amino acid profiling, it was observed that the pretreatment time did not significantly affect the structure or composition of the gelatine. However, some variation was found in its molecular weight distribution and therefore in its rheological properties: with an increase in the pretreatment time, both the molecular weight and the storage modulus of the gel also increased, as well as the gelation and melting temperatures. This contribution offers a simplified process that reduces environmental impact and provides the opportunity to tailor the final product.

Design and Manufacturing of Thermosyphon Solar Water Heater Using Locally Available Materials in Nsanke Village

The weather conditions of Nsanke village starting from April to October emphasis the need for judicious utilization of warm water. We designed, constructed and tested a Solar Water Heater based on Thermosyphon principle in Nsanke village using locally available materials. Solar energy is received by two flat-plate collectors of 1.68 m2 each, consisting of absorber plate carrying copper tubes and placed in an insulated casing with a transparent glass cover of thickness 4 mm. The collectors are connected in series and are assumed to operate on the same efficiency. The resultant collector is connected to a storage tank, which is an association of two barrel nested overall and separated with an insulator. The radiation emitted by the absorber plates cannot escape through the glass, thus increasing its temperature. The system’s performance evaluation has shown that it can heat water from 23°C to at least 51°C on sunny days. The water heated flows into a storage tank through Thermosyphon principle. The Solar Water Heating System uses the Thermosyphon principle and can therefore be called Thermosyphon Solar Water Heater (TSWH) for simplicity. This system finds useful application in serving as a renewable energy resource in Nsanke village and neighboring villages.

Diversity and paleoecological significance of zooxanthellate corals of Oligocene Qom Formation, SE Iran

Zooxanthellate corals are Iran's most abundant macrofossils in the Oligocene-early Miocene Qom Formation deposits in the NE margin of the Tethyan Seaway. Yet, basic knowledge about the diversity of these organisms and their paleoecology is still scarce. This paper uses late Rupelian–Chattian coral data from three exposed sections in the northwestern Jazmurian Lake, SE Iran, as the southeasternmost outcrops of the Qom Formation, are analyzed in terms of diversity and paleoecology. The coralline red algae and larger benthic foraminiferal assemblages associated with the corals have also been used to infer the paleoenvironmental and paleoecological conditions. The following coral genera were recognized: Leptoria, Caulastraea, Hydnophora, Astreopora, Plesiastrea, Thegioastraea, Porites, Goniopora, Platycoenia, Acropora, Tarbellastraea, Favites, Heliastraea, Stylocoenia, Ceratotrochus. The high abundance of z-corals, larger benthic foraminifera (LBF), and coralline red algae demonstrate that the deposition took place in tropical-subtropical warm waters mainly within the euphotic to the mesophotic zones. The presence of various coral fabrics including pillarstone, domestone, and rudstone allowed to infer high to moderate hydrodynamic energy in the studied sections. As well, given the interactions among corals, filter-feeders, green and red algae, bioeroders, and the surrounding environment, it seems that oligotrophic to slightly mesotrophic conditions also had prevailed in the studied area.

Marine migration, thermal habitat use and feeding habits of Arctic charr (Salvelinus alpinus (L. 1758)) in SW Greenland

Climate change is altering northern coastal aquatic habitats, especially in fjords. Data on current ecosystem structure and biodiversity in many northern fjord and coastal ecosystems, especially for Greenland, are lacking. We used acoustic telemetry combined with stable isotope analyses in a southwest Greenland fjord to investigate marine migrations, marine and freshwater thermal habitat use, and the marine feeding habits of 80 acoustically tagged Arctic charr over one year. During summer, most Arctic charr occupied the inner fjord. Models of Arctic charr thermal habitat use suggested higher experienced water temperatures in the inner compared to outer fjord (estimated 1.59ºC difference) during tagged charr mean 70-day (S.D.=14 days) residencies. During February and March, non-migratory individuals used warmer waters (+ 0.56ºC higher) than fish that ultimately migrated to sea, suggesting that over-wintering habitat use patterns influenced migration tactics. Stable isotope mixing model analysis indicated that Arctic charr fed mainly on capelin, marine gammarids and three-spine sticklebacks. The results provide a contemporary baseline for assessing predictions of potential changes in the ecology of Arctic charr in SW Greenland fjords.

Simulating Mixed‐Phase Open Cellular Clouds Observed During COMBLE: Evaluation of Parameterized Turbulence Closure

AbstractMarine cold‐air outbreaks, or CAOs, are airmass transformations whereby relatively cold boundary layer (BL) air is transported over relatively warm water. To more deeply understand BL and mixed‐phase cloud properties during CAO conditions, the Cold‐Air Outbreaks in the Marine Boundary Layer Experiment (COMBLE) took place from late 2019 into early 2020. During COMBLE, the U.S. Department of Energy's first Atmospheric Radiation Measurement Mobile Facility (AMF1) was deployed to Andenes, Norway, far downstream (∼1,000 km) from the Arctic pack ice. This study examines the two most intense CAOs sampled at the AMF1 site. The observed BL structures are open cellular with high (∼3–5 km) and cold (−30 to −50 C) cloud tops, and they often have pockets of high liquid water paths (LWPs; up to ∼1,000 g ) associated with strong updrafts and enhanced turbulence. We use a high‐resolution mesoscale model to explore how well four turbulence closure methods represent open cellular clouds. After applying a radar simulator to model outputs for direct evaluation, cloud top properties agree well with AMF1 observations (within ∼10%), but radar reflectivity and LWP agreement is more variable. Results suggest that the turbulent Prandtl number may play an important role for the simulated BL and cloud properties. All simulations produce enhanced precipitation rates that are well‐correlated with a cloud transition. Finally, the eddy‐diffusivity/mass‐flux approach produces the deepest cloud layer and therefore the largest and most coherent cellular structures. We recommend the use of a non‐local turbulence closure approach to better capture turbulent processes in intense CAOs.

Investigation of cabin heating in electric vehicles with integrating solar cells and heat storage systems

In recent years, the production and usage of electric vehicles have been encouraged due to zero emissions, efficiency, and economic factors. Efficient cabin heating and thermal management in electric vehicles are crucial for enhancing passenger comfort, extending battery life, and optimizing overall energy usage, thus contributing to the sustainability and practicality of electric transportation. Heating the cabin of electric vehicles in winter has a negative effect on range. Therefore, methods are being researched to use energy efficiently without sacrificing passenger comfort and minimizing the effect on the vehicle's range. This study presents an innovative radiator design specifically crafted for Electric Vehicles (EVs), leveraging solar panels to heat water for the radiator. This system enables the vehicle to harness solar energy for heating a water tank while stationary, effectively serving as an energy storage reservoir. Upon vehicle movement, the radiator system activates to disperse the stored thermal energy throughout the cabin, ensuring superior thermal comfort. Consequently, optimizing battery range is achieved as the heating load typically leads to significant range reductions. From the obtained results in experiment 2, the results indicated that the cabin temperature rose from 3 °C to around 15 °C within a few minutes, reflecting an increase of approximately 12 °C. According to the results, this indicates that there will be a reduction in energy consumption of between 1.9 % and 3 % for a one-hour travel range in this electric vehicle. The findings of this investigation demonstrate that utilizing warm water energy storage effectively enhances cabin thermal management.

On the Relation between Thermohaline Anomalies and Water Mass Transformation in the Eastern Subpolar North Atlantic

Abstract Decadal thermohaline anomalies carried northward by the North Atlantic Current are an important source of predictability in the North Atlantic region. Here, we investigate whether these thermohaline anomalies influence surface-forced water mass transformation (SFWMT) in the eastern subpolar gyre using the reanalyses EN4.2.2 for the ocean and the ERA5 for the atmosphere. In addition, we follow the propagation of thermohaline anomalies along two paths: in the subpolar North Atlantic and the Norwegian Sea. We use observation-based datasets (HadISST, EN4.2.2, and Ishii) between 1947 and 2021 and apply complex empirical orthogonal functions. Our results show that when a warm anomaly enters the eastern subpolar gyre, more SFWMT occurs in light-density classes (27.0–27.2 kg m−3). In contrast, when a cold anomaly enters the eastern subpolar gyre, more SFWMT occurs in denser classes (27.4–27.5 kg m−3). Following the thermohaline anomalies in both paths, we find alternating warm–salty and cold–fresh subsurface anomalies, repeating throughout the 74-yr-long record with four warm–salty and cold–fresh periods after the 1950s. The cold–fresh anomaly periods happen simultaneously with the Great Salinity Anomaly events. Moreover, the propagation of thermohaline anomalies is faster in the subpolar North Atlantic (SPNA) than in the Norwegian Sea, especially for temperature anomalies. These findings might have implications for our understanding of the decadal variability of the lower limb of the Atlantic meridional overturning circulation and predictability in the North Atlantic region. Significance Statement Anomalously warm–salty or cold–fresh water, carried by the North Atlantic Current toward the Arctic, is a source of climate predictability. In this study, we investigate 1) how these ocean anomalies influence the transformation of water masses in the eastern subpolar gyre and 2) their subsequent propagation poleward and northwestward. The key findings reveal that anomalously warm waters entering the eastern subpolar gyre lead to increased transformation in lighter water masses, while cold anomalies affect denser water masses. These anomalies propagate more than 2 times faster toward the Greenland coast (northwestward) than toward the Arctic (poleward). Our findings contribute to enhancing the understanding of decadal predictability in the northern North Atlantic, including its influence on the Atlantic meridional overturning circulation.

PSXII-9 Effects of lauric acid- and hops-based products on select microbial populations of aerobically exposed silage

Abstract Air exposed silages can harbor spoilage and pathogenic microbes which can reduce the palatability, nutritive quality and microbial safety of these feedstuffs. Accordingly, effective, environmentally friendly interventions are sought to rescue the biological and economical value of spoiled silages. The objectives of this study were to test the effects of treating air exposed corn silage with LipoVital GL-45, a Berg + Schmidt GmbH & Co. KG (Hamburg, Germany) product containing 45% monoglyceride of lauric acid (mixed within a 50% di/triglyceride base) alone or mixed with either Chinook or Galena hops or with an experimental extract containing hops β-acids. All treatments were administered as a warm water spray to deliver 1.6% product to the silage on a dry matter basis. Silage samples collected after 24 h ambient incubation were serially diluted in 0.4 M sodium phosphate buffer (pH 6.4) and plated to 3M Petrifilm for enumeration of yeast and molds and total aerobes as well as to Rogosa SL for enumeration of lactic acid bacteria and streptococci. Fluid samples from sampled silage were also inoculated in 10-fold increments to triplicate sets of tubes containing anaerobically prepared Reinforced Clostridial agar supplemented cellobiose and xylose (0.05% wt/vol each) for most probable number enumeration of total anaerobes. Populations of presumptive spore-forming aerobes and anaerobes were measured as described above except inocula were heated to 80 oC for 10 min to kill vegetative cells. An analysis of variance (Statistix Analytical Software, Tallahassee, FL, USA) revealed no treatment effects on yeasts and mold populations (P > 0.05) after 24 h air exposure of the silage, with counts averaging (± SD) 5.0 ± 0.7 log10 CFU/g. Silage treated with combinations of LipoVital GL-45 with Galena hops or the β-acid extract had 0.8 to 0.9 log10 units fewer (P < 0.05) lactic acid bacteria after 24 h air exposure than untreated controls (7.4 ± 0.1 log10 CFU/g). Similarly, silage treated with the LipoVital GL-45/Galena hops combination had 0.6 to 0.7 log10 units fewer (P < 0.05) heat-sensitive and presumptive spore-forming aerobes after 24 h air exposure when compared with controls (5.5 ± 0.2 and 5.2 ± 0.2 log10 CFU/g, respectively). Conversely, most probable numbers of nonheated anaerobe populations were lower (P < 0.05) in silage treated with LipoVital GL-45 combined with the β-acid extract when compared with controls (8.6 ± 0.x and 9.9 ± 0.7 log10 cells/g) with all other treatments being similar to controls. Populations of presumptive spore-forming anaerobes in the air exposed silage were unaffected by treatments, averaging 8.3 ± 0.7 log10 cells/g. Results warrant further research to investigate whether optimized dosages and formulations of LipoVital GL-45, Galena hops and β-acid extracts may ultimately yield treatments to prevent spoilage of air-exposed silages.

Clean and sustainable recovery of valuable materials from InP scrap via controlled-pressure pyrolysis–spray condensation

Indium phosphide (InP) semiconductors play an irreplaceable role in optical communication, and with the expansion of the market scale, the amount of InP scrap, which has become an important secondary resource for recovering phosphorus and indium, has considerably increased. However, as a typical phosphorus containing material, InP scrap recycling is difficult and dangerous because phosphorus is flammable and releasing toxic and irritating smoke during combustion. In this study, a safe, clean, and sustainable “controlled-pressure pyrolysis–spray condensation” process is proposed. Firstly, InP is decomposed into phosphorus and indium under high-temperature conditions; phosphorus then evaporates into the vapor phase and is sprayed with warm water for condensation in water, whereas indium is enriched in the liquid phase. The feasibility of this process is proven by performing thermodynamic calculations and scaled-up experiments (hundred grams to kilograms) by using a self-designed equipment. At a decomposition temperature of 1323 K, micro-negative pressure, and holding time of 5 h, an indium ingot with a purity of 99.59 wt.% was obtained and the direct yield reached 98.2%. Industrial α-yellow phosphorus with a purity of >98 wt.% was obtained and safely stored in water, and the comprehensive recovery rate is >90%. The overall process produces zero waste gas, liquid, or residue. The new process is easy to implement in industrial applications when the equipment is fitted with a continuous feeding and discharging system. A convenient and safe method for the X-ray diffraction detection of yellow phosphorus is also developed in this study.

The intensity of a field simulated marine heat wave differentially modulates the transcriptome expression of Posidonia oceanica from warm and cold environments

Marine Heat Waves (MHWs) occurrence has been increasing in the Mediterranean Sea. The effects of field simulated MHWs of different intensity (medium and high temperature) on the transcriptome expression of the endemic seagrass Posidonia oceanica were evaluated considering different origins of the plant. The aim of the study was reached through a common garden transplant experiment in the North-west of Sardinia (Italy), where two P. oceanica meadows characterized by different thermal regimes (cold and warm) were chosen. MHWs were simulated in front of a power plant, that creates a natural laboratory by releasing warm water in the sea. Differential gene expression and GO enrichment analyses highlighted differences in the transcriptomic profiles of plants from cold and warm environments suggesting that the MHWs induced different levels of stress due to different tolerance to the heat event. Plants from both origins activated processes to achieve protein homeostasis, but only cold plants activated an antioxidant defense and altered sugar metabolism, both indicators of heat stress. Within plants of the same origin, a different response to MHW intensity was also detected: while warm plants showed the most complex response at high temperature rather than at medium temperature, cold plants seemed to better cope with the medium temperature intensity rather than with high temperature.