Percentage Of Biomass Research Articles

Evaluation of deep eutectic solvents for the extraction of fucoxanthin from the alga Tisochrysis lutea – COSMO-RS screening and experimental validation

Fucoxanthin is a carotenoid in algae with purported beneficial health-related properties including antioxidant, anti-photoaging, anti-metastasis, anti-hypertensive activity and more. These properties give fucoxanthin the potential to be used in cosmetic, dietary, and medicinal applications. This study evaluates the use of deep eutectic solvents (DESs) to extract fucoxanthin from the microalgae Tisochrysis lutea. Conductor-like Screening Model for Real Solvents (COSMO-RS) was used to screen the performance of 24 different types of DESs in the extraction of fucoxanthin based on their calculated capacities. Experimental extraction validation was then carried out using the 6 top-ranked DESs. The experimental results revealed that the extraction capacity of the thymol: dodecanoic acid DES (1.25: 1 molar ratio) for fucoxanthin was the most efficient (7.69 mg/g dry biomass weight (DW)) among the DESs explored under the screening conditions and was higher than the capacity of the conventional solvents methanol (6.29 mg/g DW) and ethanol (6.75 mg/g DW). This corresponded with COSMO-RS screening results. Then, the optimisation of extraction conditions for fucoxanthin using thymol: dodecanoic acid DES was further investigated, revealing that the highest yield of fucoxanthin (22.03 mg/g DW) was extracted at optimum experimental conditions at a temperature of 36.2 °C, stirring time of 2.58 h, and the biomass percentage of 11.36 %. Additionally, fucoxanthin showed good stability in thymol: dodecanoic acid DES over eleven days of storage. After seven extraction cycles, the final fucoxanthin concentration (13.06 mg/mL DES) resulted in a good reusability of the terpene-based food safe DES.

A Thermosiphon Photobioreactor for Photofermentative Hydrogen Production by Rhodopseudomonas palustris.

A thermosiphon photobioreactor (TPBR) can potentially be used for biohydrogen production, circumventing the requirement for external mixing energy inputs. In this study, a TPBR is evaluated for photofermentative hydrogen production by Rhodopseudomonas palustris (R. palustris). Experiments were conducted in a TPBR, and response surface methodology (RSM), varying biomass concentration, and light intensity and temperature were employed to determine the operating conditions for the enhancement of both hydrogen production as well as biomass suspension. Biomass concentration was found to have had the most pronounced effect on both hydrogen production as well as biomass suspension. RSM models predicted maximum specific hydrogen production rates of 0.17 mol m−3h−1 and 0.21 mmol gCDW−1h−1 at R. palustris concentrations of 1.21 and 0.4 g L−1, respectively. The experimentally measured hydrogen yield was in the range of 45 to 77% (±3.8%), and the glycerol consumption was 8 to 19% (±0.48). At a biomass concentration of 0.40 g L−1, the highest percentage of biomass (72.3%), was predicted to remain in suspension in the TPBR. Collectively, the proposed novel photobioreactor was shown to produce hydrogen as well as passively circulate biomass.

Landscape conservation as a strategy for recovering biodiversity: Lessons from a long‐term program of pasture restoration in the southern Atlantic Forest

Abstract Although ecological restoration has entered the global agenda to reverse different anthropogenic disturbances, we still know little about how this solution interacts with other conservation strategies, to avoid the progressive loss of species and ecosystem services. Here we evaluate one of the pioneering restoration programs in the southern Brazilian Atlantic Forest, where the combination of conservation and restoration efforts has been carried out for 20 years. Specifically, we tested how landscape characteristics, restoration strategies and environmental characteristics affect the results of the restoration of pastures. We established 65 circular plots (total 4.0 ha) along restoration areas (3–10 years) and sampled trees and shrubs composing the canopy (DBH ≥ 5 cm) and understorey (DBH < 5 cm, height > 1.3 m). We analysed the landscape metrics (proportion of old‐growth forests in 200, 500 and 1,000 m buffers around each plot; and area and distance of the nearest‐neighbouring old‐growth forests). We explored the multiple effects of landscape, restoration strategy (reforestation, natural regeneration) and environmental variables (soil, pasture grass types) on the species composition and multiple diversity metrics of restoration areas. The species composition was very similar among restoration ages and restoration strategies. We found positive and strong effects of old‐growth forest (200 m buffer) proportion on the species richness and Shannon diversity (canopy and understorey), above‐ground biomass (canopy) and functional diversity (understorey) of restoration areas. The restoration strategies affected forest structure, and, in general, the reforestation strategy increased above‐ground biomass, Shannon, functional and phylogenetic diversities (in canopy), and percentage of endemic species and biomass (understorey), when compared to natural regeneration. The 20‐year experience in the southern Atlantic Forest showed that programs focused on landscape conservation associated with a mixture of restoration strategies (i.e. natural regeneration in larger areas and active restoration in more disturbed sites), can be an efficient strategy to ensure biodiversity and ecosystem services in tropical landscapes. Synthesis and applications. To manage degraded tropical lands and achieve global targets for biodiversity and ecosystem services, it is necessary to first ensure the conservation of natural remnants and then use multiple restoration strategies in less resilient areas.

Litter production in successional forests of southern Bahia, Brazil

AbstractLitter production plays an important role in the functioning of the ecosystem, providing several ecosystem services, such as nutrients cycling and carbon storage. We studied litter production patterns and its relationship with forest structure over a chronosequence of secondary forests in southern Bahia, Brazil. In the study area, 15 pairs of mature and secondary forest were used, in a chronological sequence, being 10, 25 and 40-year-old secondary forests and mature forests. Plots were created for the collection of aboveground biomass data, and within these plots, litter collectors were installed and monitored for 1 year. The results showed that litter production was lower in 10-year-old secondary forests when compared with older forests. On the other hand, in the 10-year-old forests, annual litter production represents 47.8% of the stored biomass, while in mature forests annual litter production represents only 4%. We found that structural variables (basal area, number of stems and canopy opening) influence significantly litter production, as well as litter as percentage of forest biomass. The study emphasizes the importance of biomass production through litterfall in regenerating tropical forests, and its importance for carbon storage and for the maintenance of ecosystem services.

Estimation of Carbon Metabolism in Saccharomyces cerevisiae Acclimatized to Glycerol Assimilation with Quantitative PCR.

Saccharomyces cerevisiae has the potential to produce value-added chemicals; however, this strain is restricted by using glycerol as a carbon source. Although acclimatization of S. cerevisiae as a glycerol-assimilating strain was confirmed so far, the reason why S. cerevisiae can be acclimatized was not clear in detail with limited information on the metabolic changes. In this report, glycerol-assimilating strains from S. cerevisiae BY4741 were isolated, and the biomass production, ethanol fermentation, and transcription levels related to glycolysis and the tricarboxylic acid cycle under aerobic and slightly anaerobic conditions were analyzed. As the results show, although µmax was equal to 0.15 h−1 between wildtype and glycerol-assimilating strains in an aerobic culture including glucose, the differences in max biomass production and percentage yields of ethanol and transcription levels between the two strains were shown. In slightly anaerobic culture, the differences in transcription levels downstream of glycolysis were also displayed. In the case of the glycerol-assimilating strain with glycerol under aerobic conditions, although the transcription levels related to ethanol production were sufficient, the ethanol production was not detected. Additionally, the biomass production reached a plateau even in the culture containing sufficient glycerol, indicating that the redox imbalance even in the cells of the glycerol-acclimatized strain could disturb the utilization of glycerol. The obtained knowledge will promote the use of glycerol resources with the glycerol-acclimatized S. cerevisiae in view of carbon recycling.

Aquatic particulate absorption coefficient combining extraction and bleaching optimized for inland waters

AbstractThe particulate absorption coefficient is one of the fundamental inherent optical properties describing interactions of light with material in water. Its spectral properties contain important information about chemical and biological constituents. It is often partitioned into algal and non‐algal fractions which provide useful information describing phytoplankton. Particulate absorption coefficient has been routinely measured in the ocean particularly to calibrate remote sensing algorithms. However, the methods to measure marine algal and non‐algal absorbing fractions might fail in freshwaters due to difficulties extracting green‐algae pigments and cyanobacterial phycocyanin and the high organic content of the non‐algal particles, making direct bleaching biased. In this work, we describe a method with sequential extraction, bleaching, and post‐processing to obtain unbiased pigments and non‐algal absorption fractions in freshwater environments, and we compare it against the resulting fractions obtained by only extraction or bleaching, using samples collected from 649 lakes across Canada. The resulting non‐algal particles spectra from our method appear free of interfering pigments while maintaining spectral shapes, as verified by the higher correlation coefficient between the 400 and 700 nm exponential coefficient (S, often referred to as slope) of the non‐algal particles spectra and the organic fraction of total suspended solids, and by having a better correlation between the ratio of absorption coefficient of phytoplankton at 620 and 676 nm and cyanobacterial biomass percentage. Overall, this method solves the two problems in freshwater particulate absorption partitioning associated with (1) unextracted pigments with methanol extraction methods and (2) bias introduced to non‐algal absorption spectra from NaOH bleaching.

Flammability in tropical savannas: Variation among growth forms and seasons in Cerrado

AbstractThe herbaceous layer is the dominant fuel for fire in tropical savannas, the world's most fire‐prone biome. However, little is known about variation in flammability among different growth forms, as well as how flammability varies seasonally. Here, we describe such variation in Brazilian Cerrado, the world's most phytodiverse tropical savanna. We measured three components of flammability (maximum burning temperature, burning rate, and burnt biomass) and morphophysiological traits (dead biomass percentage, moisture content, and specific leaf area) of five species of each of grasses, forbs, and shrubs throughout the wet and dry season. We found that grasses were the most flammable growth form and that their flammability was highest in the middle of the dry season when the percentage of dead biomass was highest (60%), and moisture content was low (25%). Flammability did not vary across seasons for either forbs or shrubs. Dead biomass, moisture content, and specific leaf area were all strongly correlated with flammability. These findings explain the dominant role played by grasses as drivers of flammability in tropical savannas, and they improve our understanding of how savanna flammability varies across space and time depending on the composition of the grass layer and its level of seasonal curing. This enables a better prediction of fire spread and behavior in different savanna types based on grass‐layer composition.

Stenocereus queretaroensis a source of endophytic plant growth promoting bacteria for cropping Zea mays

Healthy growth of Zea mays requires NH4NO3 as nitrogen fertilizer (NF), and its uptake is important to avoid loss of the NF. An alternative solution to enhance the root uptake capacity of Z. mays of NF at a dose to supply Z. mays demand without compromise its health; with beneficial entophytic genera and species of Stenocereus queretaroensis of the type Burkholderia vietnamiensis and Gluconacetobacter diazotrophicus. The objectives of this research were: a) to select from the interior of roots of Stenocereus queretaroensis: B. vietnamiensis and G. diazotrophicus, b) to analyze the growth of Z. mays with B. vietnamiensis and G. diazotrophicus and NF at 50%. B. vietnamiensis and G. diazotrophicus were recovered from the roots of S. queretaroensis and inoculated on Z. mays seed with NF. Using the response variables: percentage of emergency, phenology and biomass to seedling and flowering, the experimental data were analyzed by ANOVA-Tukey (P ≤ 0.05). The percentage of emergency, phenology, and biomass at seedling and flowering of Z. mays with B. vietnamiensis and G. diazotrophicus at 50% of NH4NO3, registered numerical values with statistical difference compared to those obtained in Z. mays without B. vietnamiensis and G. diazotrophicus only with NF at 100% or relative control (RC). This supports that B. vietnamiensis and G. diazotrophicus, entophytes of S. queretaroensis, invading the interior of Z. mays roots, converted metabolites related to root physiology into phytohormones that allowed maximum root uptake of NH4NO3 at 50%

Do improved biomass cookstoves reduce fuelwood consumption and carbon emissions? Evidence from a field experiment in rural Ethiopia

Using a randomized experimental design, real-time electronic stove surface temperature measurements and controlled cooking tests, we estimate fuelwood and CO2 savings from an improved cookstove (ICS) program in rural Ethiopia. Cooking uses a majority of the fuelwood in the country and therefore is a critical determinant of greenhouse gas emissions. Estimating fuelwood savings is therefore a key aspect of crediting ICS climate change benefits. Our findings suggest that the Mirt injera stove saves a substantial amount of fuelwood. Using a relatively low estimate of percentage of nonrenewable biomass, on average one Mirt stove avoids the burning of approximately 634 kg of fuelwood per year and sequesters an additional 0.65 tons of CO2, which is about one-third of previous estimates. The U.S. Interagency Working Group (2013) 2015–2019 estimate for the global social cost of carbon of $44.00 per ton implies annual global benefits from reduced fuelwood burning of $28.60 per stove per year, which substantially exceeds the $12.00 initial cost of the stove. As the global benefit is much greater than the cost, which is borne entirely by Ethiopia, international transfers would be warranted to support expansion of Mirt adoption.

Managing Forbs Preferred by Greater Sage-Grouse and Soil Moisture in Mesic Meadows with Short-Duration Grazing

Mesic meadows provide valuable water and forage resources for wildlife and livestock in the arid western United States. Greater sage-grouse (Centrocercus urophasianus), a species of conservation concern, rely on these habitats because they support forb species of high importance to broods during late brood rearing. Because mesic meadows comprise a small fraction of the landscape, identifying grazing strategies compatible with maintenance and production of mesic resources is vital to balancing livestock production with suitable conditions for sage-grouse. We evaluated relationships between short-duration grazing treatments and habitat components important to sage-grouse in mesic meadows. In 2019 and 2020, we implemented short-duration (16 d) grazing treatments that varied by season (Early: early June; Late: early August) and intensity (control: 0%, moderate: 30−40%, high: 70−80% relative use). We evaluated cover and biomass percentages of high importance forbs (HIF), soil moisture, and noxious weed cover before and after grazing and again after pasture regrowth (Early: ≈13 wk, Late: ≈6 wk). Short-duration treatments did not reduce HIF cover or biomass. Early-season (P = 0.018) and high-intensity (P = 0.04) grazing increased HIF cover during the pregrazing sample period from 2019 to 2020, suggesting positive effects of these treatments on HIF cover during the pregrazing sample period. Postgrazing HIF cover and biomass percentages remained similar across treatments. Percentages of HIF biomass after regrowth were greater (P = 0.04) in early-season than late-season treatments in 2020. Seasonal declines in soil moisture from pregrazing to regrowth sample periods were greater (P < 0.001) in early-season treatments than late-season treatments but not associated with grazing intensity (P = 0.60). Cover of noxious weeds remained unchanged under short-duration treatments. Our study emphasizes the potential of early-season, high-intensity grazing to increase HIF cover and biomass for brood-rearing sage-grouse in mesic meadows over short time intervals.

Altitudinal niches of symbiotic, associative and free-living diazotrophs driven by soil moisture and temperature in the alpine meadow on the Tibetan Plateau

Legume-associated symbiotic diazotrophs contribute more to nitrogen (N) fixation than non-symbiotic diazotrophs in many terrestrial ecosystems. However, the percentage of legume biomass is low in alpine meadows on the Tibetan Plateau. Therefore, non-symbiotic diazotrophs may play important roles in N fixation in alpine meadow soils. Moreover, Tibetan alpine meadows are fragile and sensitive to global climate change, and the investigating of the key factor driving soil diazotrophic community still entails several challenges. To address these issues, we investigated diazotrophic spatial distribution and diversity along the elevational gradient between 3200 and 4200 m in the alpine meadow using amplicon sequencing of nifH gene. The result clearly showed that soil moisture and temperature were key factors driving soil diazotrophic community structures. Both altitude and soil depth significantly differentiated diazotrophic community composition. Alpha diversity indices of diazotrophic communities showed unimodal distribution along elevation gradient, strongly affected by soil moisture. Altitudinal niches were occupied by different diazotrophs. Soils at lower elevations were dominated by symbiotic diazotrophs and associative diazotrophs related to high biomass of plant hosts, while those at higher elevations were dominated by free-living psychrophiles such as Polaromonas. Furthermore, high moisture stimulated free-living anaerobes at middle elevations, such as Geobacter and Anaeromyxobacter, while suppressed legumes and symbiotic Mezorhizobium. Soil temperature not only directly affected temperature-sensitive diazotrophs, but also indirectly affected them through plants and soil properties such as pH and ammonium content. Our results suggest that climate change may strongly affect biological nitrogen fixation (BNF), and free-living diazotrophs may play important roles in BNF of alpine meadow system on the Tibetan Plateau.

Amphibian Biomass Export from Geographically Isolated Wetlands: Temporal Variability, Species Composition, and Potential Implications for Terrestrial Ecosystems

Recently metamorphosed amphibians transport substantial biomass and nutrients from wetlands to terrestrial ecosystems. Previous estimates (except 1) were limited to either a subset of the community or a single year. Our goal was to examine temporal variability in biomass export of all amphibians within breeding ponds and the composition of that export. We completely encircled ponds with drift fences to capture, count, and weigh emerging recently metamorphosed individuals in Maine (four wetlands, six years) and Missouri (eight wetlands, 2–4 years). We estimated total amphibian biomass export, export scaled by pond surface area, species diversity, and percentage of biomass from anurans. Biomass export and export composition varied greatly among ponds and years. Our estimates were of similar magnitude to previous studies. Amphibian biomass export was higher when species diversity was low and the proportion of anurans was higher. Biomass estimates tended to be highest for juvenile cohorts dominated by a single ranid species: green frogs (Missouri) or wood frogs (Maine). Ranid frogs made up a substantial proportion of amphibian biomass export, suggesting that terrestrial impacts will likely occur in the leaf litter of forests. Future studies should examine the impacts of ranid juveniles on terrestrial ecosystem dynamics.

Medicinal Plants in Semi-Natural Grasslands: Impact of Management

Semi-natural grasslands (SNG) are valuable for their high biodiversity, cultural and landscape values. Quantitative information about medicinal plants (MP) in SNG facilitates the evaluation of ecosystem services of these habitats. Different literature sources were used to assess the ratio and frequency of MP species in several Estonian SNG and to evaluate the impact of management on these values. Lists of MP species according to different MP definition scenarios are available. The ratio of MP species in the local plant species list was the largest in alvars, followed by floodplain and wooded meadows. The average number of MP species in wooded meadows and alvars was about twice of that found in naturally growing broadleaved forest (according to the most detailed MP species list, 7.2, 7.8 and 4.3 plot−1, respectively). Fertilization of wooded meadows had no significant impact on MP species ratio, but decreased the percentage of MP biomass. Coastal meadows had few MP species and the impact of management quality depended on adopted MP scenarios. Comparison of Ellenberg indicator values revealed that MP species were more drought-tolerant, with higher commonness and more anthropophyte than the rest of studied grassland species.

Dose–response screening of industrial hemp to herbicides commonly used in corn and soybean

AbstractRecent legalization of industrial hemp in the United States has led to increased interest among stakeholders to produce hemp for grain and fiber. However, owing to the lack of herbicides registered for use in hemp, producers are left with limited weed management strategies. Moreover, much of the agricultural land that could be used to cultivate industrial hemp may be prone to carryover of previously applied residual herbicides or physical drift from herbicides sprayed nearby. Industrial hemp sensitivity to herbicides is not well documented. Dose–response studies were conducted under controlled conditions in Madison, WI, screening two industrial hemp grain cultivars for tolerance to 44 preemergence and postemergence herbicides commonly used in corn and soybean. Treatments consisted of herbicides applied at 0×, 0.125×, 0.25×, 0.50×, 0.75×, 1×, 2×, and 4× the recommended maximum labeled rates based on soil type. Preemergence applications were delivered immediately after planting, whereas postemergence applications took place when hemp plants reached 5 to 10 cm in height. Nontreated plants served as the control and were used to estimate percent biomass reduction; dose–response curves were generated. Biomass reduction was &gt;50% for rates under the suggested label rate for 23 preemergence and 21 postemergence herbicides tested. All herbicides tested resulted in &gt;25% biomass reduction at the 0.125× rate, except for clopyralid applied preemergence and postemergence and saflufenacil applied preemergence. This is concerning, as the label rates are determined for effective weed control and the mitigation of herbicide resistance. Overall, these results indicate that industrial hemp is very sensitive to most herbicides tested. Growers should consider herbicide use history and surrounding crops when determining industrial hemp field selection to prevent significant plant injury due to herbicide carryover and drift. Further research into alternative methods of weed control will be vital to establishing hemp as a dominant crop once again.

Potential of Earthworm (Perionyx Excavatus) in food treatment in Ho Chi Minh City

In Ho Chi Minh City, Vietnam, there are about 9 thousand tons of domestic waste every day and 73% of them are treated by using landfill sites [2]. With the population growth rate in recent years, the generated waste volume will then increase in the future and is estimated to reach a total of around 13 thousand tons that could cost Ho Chi Minh City about 260 thousand dollars in treating this waste in 2025 [3]. Although this treatment method is not without advantages, the downsides will be far more significant. Moreover, in recent years, the cultivation of Perionyx Excavatus, a species that had been reported to have the ability to treat organic waste in some foreign articles, has become increasingly popular in Vietnam. So, this research was aimed to evaluate the potentiality of Earthworm (Perionyx Excavatus) for food waste management of households in Lab-scale in Ho Chi Minh City, Vietnam. According to this study, the average outdoor humidity and temperature of Ho Chi Minh City are higher than optimal conditions to raise Earthworm. In addition, the percentage of biomass is highest when rising the proportion of food waste and cow dung 4:6, respectively. It’s a point for encourage the applying Earthworm (Perionyx Excavatus) for food waste management in Ho Chi Minh.

Impact of Irrigation Canal Operations on the Fish Communities and Biomass of a Connected Stream

The influence of canal operations on the available habitat and fish communities in conjoined Great Plains streams is not well understood. Three-pass backpack electrofishing was used twice within a three-week period in fall 2018 to identify changes in Turkey Creek (near Kearney, NE) before and after the Kearney Canal was dewatered. Diversity was greater while the canal was operational (t = 398.14, p < 0.001), but community composition remained similar following canal dewatering (J = 62.9%). Species-specific differences between the two time periods were most often observed among cyprinids and centrarchids, and nonnative species were more abundant (z = 6.0, p < 0.001) and comprised a greater percentage of the available biomass (z = 75.7, p < 0.001) when the canal was operational. The wetted width (t = 2.27, p = 0.04) and depth of Turkey Creek (t = 1.90, p = 0.06) significantly decreased after the canal ceased operation. Findings from this case study can be used to further the understanding of fish community responses within streams conjoined with canals and may provide regional water and fish managers important information to improve future management of these systems to support native fishes while simultaneously meeting other water uses for agriculture and recreation.

Intraspecific variation in shoot flammability in Dracophyllum rosmarinifolium is not predicted by habitat environmental conditions

Flammability is a compound plant trait that can vary significantly across natural populations within species. Investigating intraspecific variation in flammability provides insights into the evolution of plant flammability and inform understanding of wildfire risk and behaviour in different habitats. We measured four flammability variables, representing ignitibility (time to ignition), sustainability (total burning time), combustibility (maximum temperature during burning) and consumability (percentage of biomass consumed by fire) to assess the shoot-level flammability of Dracophyllum rosmarinifolium (G. Forst.) (Ericaceae), a polymorphic endemic species distributed throughout New Zealand. We examined the relationship between flammability components and a suite of climatic and geographic variables (elevation, latitude, mean annual temperature (MAT), mean annual rainfall (MAR) of the sample locations, etc.). We measured shoot-level flammability components of 62 individuals across eight populations. Burning time, maximum temperature and burnt biomass were positively correlated with each other, while ignition score was independent of other flammability components. All flammability components varied significantly across the eight populations. The habitat conditions we considered were not related to any of the shoot-level flammability components of D. rosmarinifolium. Intraspecific variation in flammability in D. rosmarinifolium may be a byproduct of selection on other functional traits, such as leaf size, shoot lipid content, indicating that plant flammability is an incidental result, rather than selected for, at least in ecosystems without fire as a selective force.

Relative Inference for Paired Data: More than Meets the Eye

Relative Inference for Paired Data: More than Meets the Eye

Does an Invasive Bivalve Outperform Its Native Congener in a Heat Wave Scenario? A Laboratory Study Case with Ruditapes decussatus and R. philippinarum

Simple SummaryGlobal climate change is responsible for more frequent heat waves, which offers opportunities for invasive species to expand their range. Two congener bivalves, the native Ruditapes decussatus and the invasive R. philippinarum, were exposed to a heat wave aquaria simulation and analysed for ecological and subcellular biomarkers responses. Despite reduced responses on the ecological level (bioturbation and nutrient concentration), there were differential responses to the heat wave at the subcellular level, where the invasive species seems to be less impacted than the native by the heat wave. This reinforces the common notion that climate change events may provide opportunities for biological invasions.Global warming and the subsequent increase in the frequency of temperature anomalies are expected to affect marine and estuarine species’ population dynamics, latitudinal distribution, and fitness, allowing non-native opportunistic species to invade and thrive in new geographical areas. Bivalves represent a significant percentage of the benthic biomass in marine ecosystems worldwide, often with commercial interest, while mediating fundamental ecological processes. To understand how these temperature anomalies contribute to the success (or not) of biological invasions, two closely related species, the native Ruditapes decussatus and the introduced R. philippinarum, were exposed to a simulated heat wave. Organisms of both species were exposed to mean summer temperature (~18 °C) for 6 days, followed by 6 days of simulated heat wave conditions (~22 °C). Both species were analysed for key ecological processes such as bioturbation and nutrient generation—which are significant proxies for benthic function and habitat quality—and subcellular biomarkers—oxidative stress and damage, and energetic metabolism. Results showed subcellular responses to heat waves. However, such responses were not expressed at the addressed ecological levels. The subcellular responses to the heat wave in the invasive R. philippinarum pinpoint less damage and higher cellular energy allocation to cope with thermal stress, which may further improve its fitness and thus invasiveness behaviour.

Presence of Common Kingfisher on the Coast: The Potential Importance of Shrimp as Prey in Marine Habitats

The feeding ecology and distribution of the Common Kingfisher Alcedo atthis has been extensively studied during the breeding season in European freshwater habitats, but there is much less known about the ecology of this species in marine and brackish habitats. This study aims to (1) document the presence of Common Kingfishers in marine habitats of Galicia (NW Spain), based on a database of bird sightings collected in mainland Galicia (2004–2020) and on the Cíes Islands (Coast of Galicia; 2008–2019), and (2) study their diet in marine habitats, analyzing 17 pellets collected during autumn and winter in a coastal salt lagoon on the Cíes Islands. During autumn and winter, the number of observations of the species in mainland Galicia were higher in marine habitats than in freshwater habitats (χ21 = 10.88, P < 0.001). Moreover, Common Kingfishers visit the Cíes Islands mostly during autumn and winter (98.6% of observations). Both datasets show that marine habitats are very important for wintering birds. In the coastal lagoon on the Cíes Islands, the Common Prawn Palaemon serratus was the most frequent prey (41.7%), accounting for the highest percentage of the total biomass (68%); much more than the second most frequent prey, gobies (Gobiidae; 35.5%). This finding is exceptional in Europe, since only a few studies report shrimp as a prey item for Common Kingfishers, probably due to the lack of data from marine habitats during winter.