Percentage Of Biomass Research Articles

Study on the effects of beta cyclodextrin‐zinc oxide nanoparticles as heterogeneous catalysts in microbial oil fermentation

AbstractIn order to study the catalytic activity of beta cyclodextrin‐encapsulated zinc oxide (ZnO) nanoparticles in microbial oil synthesis, rice‐washed waste water (RWW) was used as the fermentation medium and streptomyces fradiae as the microbe. The introduction of zinc oxide nanoparticles during fermentation had an impact on output and growth. The biomass percentage was 1.5 times greater and the fatty acid profile was better than in the control samples. The analysis of the induction period (IP) revealed that samples containing zinc oxide nanoparticles had maximum oxidation stability for up to 120 days of storage, along with a considerable reduction in autoxidation. The cetane number and calorific value, however, increased with the addition of ZnO nanoparticles. A new study discovered that the use of ZnO nanoparticles encapsulated in β‐CD led to much increased production (63.5 g/L) of microbial oil than the control sample (42.5 g/L). Therefore, it is anticipated that these nanoparticles would find utility in energy‐related applications.

Evaluation of Two Ecosystem Services Provided by a Pistia stratiotes Population on the Pacific Coast of South America.

One of the most fascinating wetlands on Peru's central coast is the Santa Rosa wetland (Chancay, Lima), an ecosystem threatened by anthropogenic activities. Some of these impacts have led to the uncontrolled growth of Pistia stratiotes, an invasive aquatic plant. This study sought to quantify the regulation and provisioning of ecosystem services provided by P. stratiotes using carbon storage and the provision of biomass as indicators. To this end, the biomasses of 50 plots measuring 0.0625 m2 were weighed and georeferenced and the percentages of dry biomass (%DB) and total organic carbon in the biomass (%C) were quantified. The biomass and its coordinates were entered into ArcGIS and a Kriging interpolation technique was applied to determine the total amount of biomass (B). It was found that P. stratiotes stored 3942.57 tCO2 and that 2132.41 tons of biomass could be obtained for fodder. The total carbon stored by this aquatic plant represented 28.46% of the total carbon sequestered in the wetland ecosystem by vascular plants, suggesting that its contribution to the carbon cycle is significant. This is the first study to estimate the biomass of a floating aquatic plant population in a coastal Peruvian wetland and is a pioneering study addressing the in situ carbon estimation of Peruvian floating aquatic plants. The results and methods proposed in this research will serve in the evaluation of the potential of ecosystem services among similar populations of floating aquatic species. In addition, the data presented can be used to establish plans for the management and use of this biomass in the production of soil fertilizers and cattle forage.

Utilizing Food Waste in 3D-Printed PLA Formulations to Achieve Sustainable and Customizable Controlled Delivery Systems.

This is the first study that explores blending polylactic acid (PLA) with various biomasses, including food wastes-brewer's spent grain (BSG), spent coffee grounds (SCG), sesame cake (SC), and thermoplastic starch (TPS) biomass to create composite gastric floating drug delivery systems (GFDDS) through 3D printing. The aim is to investigate the influence of biomass percentage, biomass type, and printing parameters on their corresponding drug release profiles. 3D-printed (3DP) composite filaments were prepared by blending biomasses and PLA before in vitro drug release studies were performed using hydrophilic and hydrophobic model drugs, metoprolol tartrate (MT), and risperidone (RIS). The data revealed that release profiles were influenced by composite compositions and wall thicknesses of 3DP GFDDS capsules. Up to 15% of food waste could be blended with PLA for all food waste types tested. Delivery studies for PLA-food wastes found that MT was fully released by 4 h, exhibiting burst release profiles after a lag time of 0.5 to 1.5 h, and RIS could achieve a sustained release profile of approximately 48 h. PLA-TPS was utilized as a comparison and demonstrated variable release profiles ranging from 8 to 120 h, depending on the TPS content. The results demonstrated the potential for adjusting drug release profiles by incorporating affordable biomasses into GFDDS. This study presents a promising direction for creating delivery systems that are sustainable, customizable, and cost-effective, utilizing sustainable materials that can also be employed for agricultural, nutraceutical, personal care, and wastewater treatment applications.

Various presowing treatments for enhancing Melia dubia (Cav.) seed germination, seedling development, and vigor index

Melia dubia (Cav.) is one of the most promising agroforestry multipurpose tree species. However, there is a shortage of this quality planting material due to its low germination ability. Our study assessed six different presowing treatments, namely, soaking in tap water for 24 h, soaking in a cow dung slurry for 7 days (CDS), scarification with 50 % H2SO4 for 5 min, soaking in 200 ppm gibberellic acid (GA3) for 24 h, and soaking in CDS + H2SO4, GA3 + H2SO4 or the control (no application), for enhancing seed germination and growth in Melia dubia during 2019–20 in the Indo-Gangetic Plains region. STAR version 2.0.1 was used to analyze the observed data using one-way ANOVA. The results of this study showed that different treatments substantially impacted the germination and growth of Melia dubia. Compared with those of untreated seeds (control), the germination percentage of seeds treated with cow dung slurry significantly increased by 49 %, the biomass percentage significantly increased by 25 %, and the vigor index significantly increased by 79 %. In conclusion, our study revealed that treating Melia dubia seeds with cow dung slurry for a period of 7 days enhances germination and seedling growth and is also cost-effective for nursery managers and farmers due to the absence of associated costs.

Enhancing lignite coal quality with biomass waste in slow pyrolysis Fischer-Tropsch reactor

Coal is a non-renewable natural resource that is widely used in thermal power plants in major industrialized countries. Most of the world's coal contains a high percentage of moisture and ash and a low caloric value. The slow pyrolysis process of coal improves its quality and significantly reduces its smoke and ash. In this study, Soma Kisrakdere lignite coal in Manisa province in Turkey with some biomass wastes (peanut shells, pine cones, and olive seeds) was evaluated by applying a slow pyrolysis process using a Fischer-Tropisch reactor. Firstly, Soma Kisrakdere lignite alone, then each waste biomass was mixed with lignite coal at weight percentages of 10 %, 25 %, and 50 % to form three mixtures for each biomass waste. The process temperature was 500°C, and the temperature rate was 0.1 °C/s. The findings obtained in this study showed that with the increase of weight percentages of biomass which added from biomass waste to lignite coal, the productivity of coal (biochar) decreased and the products of tar, decomposed water, and gases increased. As for calories, its value increased with the increase in weight of the addition the waste of biomass which added where 50 % of biomass additions were the highest value of low heating value (LHV) and high heating value (HHV) and most effective than others which added to lignite coal. Among the biomass residues used, the olive seeds were the most valuable, compared with the peanut shells and pine cones.

Comparative study of urea-15N fate in pure bamboo and bamboo-broadleaf mixed forests.

Bamboo is a globally significant plant with ecological, environmental, and economic bene-fits. Choosing suitable native tree species for mixed planting in bamboo forests is an effective measure for achieving both ecological and economic benefits of bamboo forests. However, little is currently known about the impact of bamboo forests on nitrogen cycling and utilization efficiency after mixing with other tree species. Therefore, our study aims to compare the nitrogen cycling in pure bamboo forests with that in mixed forests. Through field experiments, we investigated pure Qiongzhuea tumidinoda forests and Q. tumidinoda-Phellodendron chinense mixed forests, and utilized 15N tracing technology to explore the fertilization effects and fate of urea-15N in different forest stands. The results demonstrated the following: 1) in both forest stands, bamboo culms account for the highest biomass percentage (42.99%-51.86%), while the leaves exhibited the highest nitrogen concentration and total nitrogen uptake (39.25%-44.52%/29.51%-33.21%, respectively) Additionally, the average nitrogen uptake rate of one-year-old bamboo is higher (0.25 mg kg-1 a-1) compared to other age groups. 2) the urea-15N absorption in mixed forests (1066.51-1141.61 g ha-1, including 949.65-1000.07 g ha-1 for bamboo and 116.86-141.54 g ha-1 for trees) was significantly higher than that in pure forests (663.93-727.62 g ha-1, P<0.05). Additionally, the 15N recovery efficiency of culms, branches, leaves, stumps, and stump roots in mixed forests was significantly higher than that in pure forests, with increases of 43.14%, 69.09%, 36.84%, 51.63%, 69.18%, 34.60%, and 26.89%, respectively. 3) the recovery efficiency of urea-15N in mixed forests (45.81%, comprising 40.43% for bamboo and 5.38% for trees) and the residual urea-15N recovery rate in the 0-60 cm soil layer (23.46%) are significantly higher compared to those in pure forests (28.61%/18.89%). This could be attributed to the nitrogen losses in mixed forests (30.73%, including losses from ammonia volatilization, runoff, leaching, and nitrification-denitrification) being significantly lower than those in pure forests (52.50%). These findings suggest that compared to pure bamboo forests, bamboo in mixed forests exhibits higher nitrogen recovery efficiency, particularly with one-year-old bamboo playing a crucial role.

Repeat GEDI footprints measure the effects of tropical forest disturbances

More of the Amazon rainforest is disturbed each year than completely deforested, but the impact of these disturbances on the carbon cycle remains poorly understood. Recent algorithmic advances using optical and radar remote sensing have improved detection of disturbances at fine spatiotemporal resolution, but quantifying changes in forest structure and biomass associated with these detected disturbances has proven challenging. The Global Ecosystem Dynamics Investigation (GEDI), a spaceborne lidar mission collecting data from 2019 to 2023, provides an opportunity to address this problem. GEDI captured billions of measurements of forest height, plant area, and understory structure within ∼25-m diameter footprints scattered across the tropics. Though the instrument had no guaranteed repeat cycle, it sometimes sampled nearby locations twice; some of these spatially near-coincident footprints happened to measure forest structure before and after a detected disturbance, providing information on how disturbance affected aboveground biomass. In this study, we developed an efficient general-purpose open-source pipeline for identifying spatially coincident footprints, which is a computationally complex task, and used the pipeline to find over 13,700 footprint pairs with intervening disturbance events across the Amazon biome. We also identified a set of ∼65,000 spatially near-coincident footprint pairs that lacked an intervening disturbance but came from regions with similar disturbance threat; these provided a control dataset to evaluate the effectiveness of estimating forest structure and biomass changes with nearby footprints. Analysis of this Amazon-wide dataset demonstrated that GEDI was able to measure statistically significant canopy height and biomass deficits following non-stand-replacing disturbances as small as 900 m2 (30 m × 30 m). GEDI's unique three-dimensional view of forest structure also reflected the effects of different intensities of fire disturbance, including 20% of burned areas where the upper canopy retained most of its height, but the understory suffered substantial foliage losses. Finally, we modeled the relationship between Landsat and Sentinel-1 disturbance detection parameters and GEDI-estimated percent biomass loss, showing that certain satellite-derived intensity metrics are correlated with increasing biomass loss and identifying temporal trends in biomass loss and recovery following disturbance. This work represents an important step towards the development of a pan-tropical, spatially explicit system for tracking carbon losses and structural changes arising from forest disturbance.

Influence of Biogenic Material Content on the Biodegradability of Styrene-Butadiene Composites with Incorporated Chlorella vulgaris Biomass.

Bio-fillers are intensively studied for advanced polymer composite circular design and production. In this context, the algal biomass may be considered an important and relatively low-cost resource, when harvested as a by-product from wastewater treatment plants. The biomass of the algal species Chlorella vulgaris is frequently used in this type of environmental process, and its macro constituents' composition ranges from around 15-25% carbohydrates, 10-20% lipids, and 50-60% proteins. Poly (styrene-butadiene-styrene) (SBS) copolymers have a matrix composed of glassy polystyrene domains connected by flexible polybutadiene segments. Although the physical-mechanical properties of SBS copolymers recommend them for many industrial applications, they have the drawback of low biodegradability. This study aimed to assess the aerobic biodegradability of polymer composites by integrating biomass from Chlorella vulgaris at varying mass percentages of 5, 10, and 20% into SBS copolymer composites. Biodegradation tests were conducted under industrial composting conditions (58 °C and 50% relative humidity) for 180 days. The biodegradability of materials was evaluated by measuring the CO2 produced in each vessel during the study period. Potential correlations between the amount of carbon dioxide released and the percentage of biomass added to the polymer matrix were examined. Structural and morphological changes were assessed using Fourier Transform infrared spectroscopy (FTIR), thermal analysis (DSC), and scanning electron microscopy (SEM). Physical and chemical testing revealed a decrease in sample density after the industrial composting test, along with noticeable changes in melt flow index (MFI). The observed physical and chemical changes, coupled with FTIR, SEM, and DSC data, indicate increased cross-linking and higher porosity in biodegraded polymer structures with higher biomass content. This behavior is likely due to the formation of cross-linked connections between polymer chains and polypeptide chains resulting from protein degradation, enhancing connections between polystyrene units facilitated by peptide bonds with the benzene units of the styrene blocks within the polymer matrix.

Biodegradation Study of Styrene-Butadiene Composites with Incorporated Arthrospira platensis Biomass.

The preparation of polymer composites that incorporate material of a biogenic nature in the polymer matrices may lead to a reduction in fossil polymer consumption and a potentially higher biodegradability. Furthermore, microalgae biomass as biogenic filler has the advantage of fast growth and high tolerance to different types of culture media with higher production yields than those provided by the biomass of terrestrial crops. On the other hand, algal biomass can be a secondary product in wastewater treatment processes. For the present study, an SBS polymer composite (SBSC) containing 25% (w/w) copolymer SBS1 (linear copolymer: 30% styrene and 70% butadiene), 50% (w/w) copolymer SBS2 (linear copolymer: 40% styrene and 60% butadiene), and 25% (w/w) paraffin oil was prepared. Arthrospira platensis biomass (moisture content 6.0 ± 0.5%) was incorporated into the SBSC in 5, 10, 20, and 30% (w/w) ratios to obtain polymer composites with spirulina biomass. For the biodegradation studies, the ISO 14855-1:2012(E) standard was applied, with slight changes, as per the specificity of our experiments. The degradation of the studied materials was followed by quantitatively monitoring the CO2 resulting from the degradation process and captured by absorption in NaOH solution 0.5 mol/L. The structural and morphological changes induced by the industrial composting test on the materials were followed by physical-mechanical, FTIR, SEM, and DSC analysis. The obtained results were compared to create a picture of the material transformation during the composting period. Thus, the collected data indicate two biodegradation processes, of the polymer and the biomass, which take place at the same time at different rates, which influence each other. On the other hand, it is found that the material becomes less ordered, with a sponge-like morphology; the increase in the percentage of biomass leads to an advanced degree of degradation of the material. The FTIR analysis data suggest the possibility of the formation of peptide bonds between the aromatic nuclei in the styrene block and the molecular residues resulting from biomass biodegradation. It seems that in industrial composting conditions, the area of the polystyrene blocks from the SBS-based composite is preferentially transformed in the process.

Gasification Burner Performance Test Using Bio-Coal Fuel

Fuel for high-energy solid fuel combustion systems must meet abundant availability, affordability, and environmental friendliness criteria, particularly having low greenhouse gas emissions. One type of fuel that meets these criteria is bio-coal. Gasification burners employ staged combustion techniques that enhance combustion efficiency and reduce the formation of harmful substances, making them more environmentally friendly. This article discusses the performance testing of gasification burners using bio-coal as fuel, with variable primary air flow rates of 25, 30, 35, 40, and 50 m3/hour and biomass percentages in the bio-coal of 25%, 50%, and 75% by weight. The parameters observed are burner capacity, temperature, and CO2 gas emission factor. The experimental results show that increasing the air flow rate from 25 to 35 m3/hour significantly increases burner capacity and temperature, while further increasing the primary air flow rate to 50 m3/hour results in a gradual increase in burner capacity. The experiments also indicate that increasing the biomass percentage in the bio-coal slightly increases burner capacity and temperature due to the similar calorific values of palm pellet and coal used. The gasification burner technology developed by BBP Tekmira has proven to operate effectively within a capacity range of 8 to 20 kg/hour for bio-coal fuel with biomass percentages ranging from 25% to 75% by weight, producing burner temperatures between 805 and 933 degrees Celsius. Using bio-coal for gasification burners has also been shown to reduce greenhouse gas emissions when the biomass percentage in bio-coal exceeds 64%.

Dual carbon isotope-based brown carbon aerosol characteristics at a high-altitude site in the northeastern Himalayas: Role of biomass burning

PM2.5 samples (n = 34) were collected from January to April 2017 over Shillong (25.7°N, 91.9°E; 1064 m amsl), a high-altitude site situated in the northeastern Himalaya. The main aim was to understand the sources, characteristics, and optical properties of local vs long-range transported carbonaceous aerosols (CA) using chemical species and dual carbon isotopes (13C and 14C). Percentage biomass burning (BB)/biogenic fraction (fbio, calculated from 14C) varied from 67 to 92 % (78 ± 7) and correlated well with primary BB tracers like f60, and K+, suggesting BB as a considerable source. Rain events are shown to reduce the fbio fraction, indicating majority of BB-derived CA are transported. Further, δ13C (−26.6 ± 0.4) variability was very low over Shillong, suggesting it's limitations in source apportionment over the study region, if used alone. Average ratio of absorption coefficient of methanol-soluble BrC (BrCMS) to water-soluble BrC (BrCWS) at 365 nm was 1.8, indicating a significant part of BrC was water–insoluble. A good positive correlation between fbio and mass absorption efficiency of BrCWS and BrCMS at 365 nm with the higher slope for BrCMS suggests BB derived water-insoluble BrC was more absorbing. Relative radiative forcing (RRF, 300 to 2500 nm) of BrCWS and BrCMS with respect to EC were 11 ± 5 % and 23 ± 16 %, respectively. Further, the RRF of BrCMS was up to 60 %, and that of BrCWS was up to 22 % with respect to EC for the samples with fbio ≥ 0.85 (i.e., dominated by BB), reflecting the importance of BB in BrC RRF estimation.

A Multipurpose Sustainable Farming System for Tobacco Crops in the Mediterranean Area

The present study aimed to test a multipurpose sustainable tobacco farming system allowing more efficient use of production factors (e.g., mineral N fertilizer) thanks to larger commercial yields, albeit diversified (smoke products, bioactive compounds for nutraceutical and cosmeceutical uses, energy), per unit of land area. Three tobacco types (dark air-cured, IBG; light air-cured, Bu; dark fire-cured, Ky) were grown in the field in 2021 on three different soils (sandy clay loam, SCL; sandy loam, SL; clay loam, CL). The total waste biomass (WB, kg dry weight, d.w. ha−1) was measured. Commercial leaves yield (CLY, kg d.w. ha−1), N agronomic efficiency (NAE, kg d.w. kg−1 N), total polyphenols content (TP, mg kg−1 d.w.), antioxidant activity (ABTS, DPPH and FRAP, mmol Trolox Equivalent, TE, kg−1 d.w.) and yield of polyphenols (PY, kg ha−1) were determined. The calorific value (CV, MJ kg−1 d.w.), volatile matter (VM, %) and ash contents (%) were also measured, and biomass energy yield (BEY, GJ ha−1 yr−1) was then calculated. Very high percentages (&gt;40%) of total biomass produced by the different tobacco types were pre-harvest waste. NAE increased by 2- to more than 8-fold thanks to a greater potential commercial biomass produced with the same amount of N fertilizer used. Four main components were found in the tobacco polyphenols profile, namely 3-O-CQA, luteolin 7 rutinoside, rutin and quinic acid, which accounted for more than 80% of TP. BEY ranged between 122.3 GJ ha−1 yr−1 (Bu) and 29.9 GJ ha−1 yr−1 (Ky). Both polyphenols yield and energy potential per unit land area and/or per growing season appeared competitive with those from other herbaceous crops. The proposed multipurpose system appeared as a production circuit characterized by a virtuous and sustainable flow of resources.

Effect of Feeding Different Percentage of Biomass of a Certified Commercial Diet on Growth Performance and Feed Utilization for Common Carp (Cyprinus carpio L.)

This study was conducted at fish laboratory affiliated to the department of animal production/college of agriculture/University Of Anbar. The experiment lasted eight weeks in Aquatic Recirculating System ARS from 5th Sep 2022 to 31 Oct 2022, to examine the appropriate nutrient ratios of commercial diet For Common carp (Cyprinus carpio L.). One hundred twenty-six fingerlings fish with 35.44± 0.44 gm. Weight randomly divided in to six treatment by three replicates, seven fish for each replicate. It housed in aquaria, with a capacity of 50 liters, its dimensions are 30 × 30 × 60 cm for each one. All fish had fed on the same diets, they were fed as follows (T1) is unlimited, open until saturation, and the other treatments T2, T3, T4, T5 and T6 were fed by 3%, 4%, 5%, 6% and 7%, respectively from their biomass weight ratio on two meals a day. The rustle showed that T4, T5 and T6 had significant increase (P≤0.05) in final weight (FW), weight gain (WG), daily weight gain (DWG), relative growth rate (RGR), specific growth rate (SGR) as compared with others. This study it could concluded, feeding fish 4% or 5% from biomass weight ratio improving growth performance and decrease wasted fodder.

Implementation and assessment of a model including mixotrophs and the carbonate cycle (Eco3M_MIX-CarbOx v1.0) in a highly dynamic Mediterranean coastal environment (Bay of Marseille, France) – Part 1: Evolution of ecosystem composition under limited light and nutrient conditions

Abstract. Many current biogeochemical models rely on an autotrophic versus heterotrophic food web representation. However, in recent years, an increasing number of studies have begun to challenge this approach. Several authors have highlighted the importance of protists capable of combining photoautotrophic and heterotrophic nutrition in a single cell. These mixotrophic protists are known to play an important role in the carbon cycle. Here, we present a new biogeochemical model that represents the food web using variable stoichiometry. It contains the classic compartments such as zooplankton, phytoplankton, and heterotrophic bacteria and a newly added compartment to represent two types of mixotrophic protists: non-constitutive mixotrophs (NCMs) and constitutive mixotrophs (CMs). We demonstrate that the model correctly reproduces the characteristics of NCMs and CMs and proceed to study the impact of light and nutrient limitation on planktonic ecosystem structure in a highly dynamic Mediterranean coastal area, namely the Bay of Marseille (BoM, France), paying special attention to the dynamics of mixotrophic protists in these limiting conditions. In addition, we investigate the carbon, nitrogen, and phosphorus fluxes associated with mixotrophic protists and showed the following: (i) the portion of the ecosystem in terms of the percentage of carbon biomass occupied by NCMs decreases when resources (nutrient and prey concentrations) decrease, although their mixotrophy allows them to maintain a carbon biomass almost as significant as the copepod one (129.8 and 148.7 mmol C m−3, respectively), as photosynthesis increases as a food source, and (ii) the portion of the ecosystem in terms of the percentage of carbon biomass occupied by CM increases when nutrient concentrations decrease due to their capability to ingest prey to supplement their N and P needs. In addition to providing new insights regarding the conditions that lead to the emergence of mixotrophs in the BoM, this work provides a new tool to perform long-term studies and predictions of mixotroph dynamics in coastal environments under different environmental forcings.

Soil carbon mineralization, enzyme activities, and crop residue decomposition under varying soil moisture regimes

AbstractIn the Lower Mississippi River Basin, farmlands are flooded in late fall and winter by impeding drainage to provide a habitat for migratory birds stopover. A laboratory incubation study was conducted to study the influence of temporary wetting of these soils on carbon (C) and nitrogen (N) mineralization from residue decomposition. Surface soils (0–15 cm) were collected from fields with clay and silty clay loam soils. Both soils were incubated with five crop residues—corn (Zea mays), soybean (Glycine max), cotton (Gossypium hirsutum), sorghum (Sorghum bicolor), and sweet potato (Ipomea batatus)—at 50% and 100% water holding capacity (WHC). Soil carbon dioxide (CO2) efflux was measured during 74 days of incubation. Soil moisture had the largest effect on soil CO2 efflux and most of the enzyme activities followed by residue and soil type. Cumulative soil CO2 efflux was reduced by 46% at 100% WHC compared to 50% WHC. Clay soil had higher cumulative CO2 efflux, aryl sulfatase, aryl phosphatase, and β‐N‐acetyl glucose aminidase activities than silty clay loam soil. Residue type had the largest effect on post‐incubation soil inorganic‐N, remaining biomass, and residue C and residue N. Sweet potato residue had the lowest remaining biomass, significantly lower than cotton, corn, and sorghum, but statistically similar to soybean. After incubation, residue N concentration had a positive association with cumulative CO2 efflux and a negative association with remaining residue biomass percentage. Winter flooding might limit the loss of soil C as CO2 depending on the crops grown and soil type.

Steam application with paraquat to control goat weed (Scoparia dulcis) in citrus orchards

Reducing herbicide use in horticultural crop production can ameliorate adverse environmental effects but may also impact weed control effectiveness, especially as it pertains to difficult-to-control weeds. This challenge can be addressed by integrating a non-chemical strategy such as steam application with herbicide application. In this study, steam, as a non-chemical approach, was combined with post-emergence herbicide (paraquat) application for goatweed (Scoparia dulcis) management in citrus orchards. Two field trials based on randomized complete block design were conducted in citrus orchards in Immokalee, FL, in 2018 and 2021. Steam was applied to goatweed at a flow rate of 53 L ha−1 for 5–6 s. Twenty-four hours after steam application, low and high paraquat rates (0.3366 and 1.010 kg ai ha−1) were applied. In addition, the same rates of paraquat were applied without steam for comparison. Untreated checks (UTC) of no herbicide or steam applications were also included in the experiment as a control. Based on visual injury ratings, a combination of steam + low dosage of paraquat was as effective as the high dosage of paraquat alone and steam + high dosage of paraquat at 1, 8, and 16 days after treatment application (DAT) in 2018 trial and 1, 8, 16 and 22 DAT in 2021 trial.However, based on one site-year of biomass data, the percentage of dead weed biomass out of total biomass was statistically similar among all the treatments. Results from this study demonstrate that combining a low rate of paraquat applied in tandem with the steam application has the potential to provide effective goatweed control in citrus orchards.

Diet of loggerhead turtles in the Gulf of Manfredonia, South Adriatic Sea: evidence of winter feeding and anthropogenic impacts

Investigating biological aspects of migratory marine animals like sea turtles is challenging. The Adriatic Sea is a key Mediterranean foraging ground for loggerhead turtles, yet certain feeding behaviors remain poorly known, including winter feeding and foraging within the neritic area of the Gulf of Manfredonia. With high fishing effort, this area experiences considerable turtle bycatch from trawlers during winter, representing an important conservation issue. Insights on how and to what extent the species interacts with anthropogenic threats such as trawlers and debris can be obtained from diet analysis. We examined feces and gut contents from 57 bycaught or stranded turtles to assess active feeding and digestion time during winter, identify and quantify prey items, evaluate feeding patterns among size classes, and ascertain the anthropogenic impact via debris and fishing discard ingestion. Our findings show that turtles feed actively during winter, primarily on benthic items, starting from a small size (32 cm Curved Carapace Length). No size effect was observed on dietary diversity or biomass percentage. We identified 37 Operational Taxonomic Units (OTUs) across 10 dietary groups, with crustaceans and mollusks being most prevalent. Osteichthyes and cephalopods, likely scavenged from trawl discard, were also common, implying intensive local trawling may attract turtles, increasing bycatch and mortality rates. The frequency of anthropogenic material ingestion was comparable to other Mediterranean regions and its presence in feces suggests non-lethal effects, if any. This study shows how information on seasonal feeding behavior can provide insights into how the relationship of the species with the environment and threats changes over time, ultimately steering conservation efforts.

Soundscapes of the central Red Sea mesophotic reef zones

Despite covering a large amount of seafloor &amp; representing a significant percentage of coral reef ecosystem biomass, Mesophotic Coral Ecosystems (MCEs) globally have been largely understudied in comparison to their shallow counterparts. The Red Sea is a unique and biodiverse tropical ecosystem, where few mesophotic coral reefs have been studied. To define spatiotemporal activity of marine life and characterize the soundscapes of the MCE in the Central Red Sea, two locations were surveyed at 70–80 m, as well as at two adjacent shallow reef sites at ∼10 m depth, respectively, during the winter (Jan 2022) and summer (Jul–Aug 2022) seasons. The results of this study, the first of its kind in the Red Sea, show a clear shift in the soundscape between seasons, as well as between the shallow and mesophotic zones, driven mainly by a change in fish and invertebrate chorusing. During the study periods, temperature and oxygen levels in the mesophotic zone remained relatively stable, in comparison to the shallow reef zone which saw a steep temperature increase and large diel fluctuations in oxygen in the summer. Chronic exposure to shipping noise is evident across Red Sea MCE soundscapes and the resulting potential effects are discussed.

Identification of Biodegradable, Compostable or Toxic Plastic Bags with Two Beetles of the Tenebrionidae Family

Various studies have demonstrated the environmental problems caused by plastic bags (PB) made with hydrocarbons, and therefore international policies have been established to replace the use of conventional PB by biobags or compostable bags, which are designed to be biodegradable and/or composted in the environment. However, the methods used to characterize such bags are still far from being effectively assessed. This study evaluated a technique to identify biodegradable, compostable and/or toxic PB by feeding compostable bags certified by recognized institutions to larvae of the Tenebrionidae family, particularly Tenebrio molitor and Zophobas morio species. Three brands of single-use bags were studied, and the following parameters were evaluated: rate of consumption (of bags by larvae), percentage of biomass (weight increase in larvae), percentage of survival (percentage of larvae eating bags), percentage of biodegradability by evaluating the total organic carbon (TOC) in stool, and stool analysis by spectroscopy and spectrometry. The results showed differences between the rate of consumption, the EHappy bag being the most consumed; there were differences in the percentage of biomass, the EHappy bag showing less potential for biomass increase; both species showed lower survival with the Ealternative bag. TOC evaluation indicated that the WCare bag presents the highest biodegradability; the total reflectance attenuated infrared analysis showed a decrease in the representative peaks of the spectrum of PB, evidencing biodegradation; and the amount of metals in feces was found within the Maximum Permissible Limits. The two species showed a good performance, demonstrating that they can be used as a suitable and viable tool to evaluate toxicity, biodegradability and compostability.

Weed flora composition in a young olive orchard as affected by fertilizer types

Manure is a useful source of nutrients in olive orchards, but its effect on weed growth in such an ecosystem has not been studied. A field experiment was conducted in a six-year old olive orchard (cv. Chondrelia Chalkidikis) in northern Greece to study the effects of two forms of fertilization (inorganic fertilizer and composted cow manure) on weeds abundance and weed flora composition (species diversity and dominance). A randomized complete block design with three treatments (inorganic fertilizer, 150 kg N ha−1 plus 205 kg P2O5 ha−1 plus 205 kg K2O; composted cow manure, 20 Mg dry weight ha−1; and control) replicated three times was used. Inorganic fertilizer and composted cow manure had no significant effect on the number of weed species (F = 0.288, P > 0.05), but improved olive fruit yield by 61.6% and 57.1%, respectively, compared with the non-fertilized control. Both inorganic fertilizer and composted cow manure increased the weeds dry biomass by 133.4% and 80.8%, respectively, compared with the non-fertilized control. There was a decrease in the biomass proportion (percentage of the total weed biomass) of annual species with composted cow manure (x2 = 6.72, P < 0.05), while no significant change in the biomass ratio of grasses and broadleaf weeds was observed. Fertilization increased the growth of Chenopodium album, mainly with the addition of inorganic fertilization; and Sonchus oleraceus, slightly more with the addition of composted cow manure. Centaurea solstitialis and Daucus carota had a high proportion only in the non-fertilized control plots. Composted cow manure can be used as an alternative fertilizer in olive orchards, without enriching weed flora in terms of species number. Long-term experiments would be useful to confirm the influence of composted cow manure on weed flora of olive orchards.