Unveiling amending properties of biosolids from constructed wetland systems: a comparative study.

Climate change and intensive farming have caused soil degradation and decreased organic carbon stocks. Current research focuses on restoring soil fertility, often through organic amendments. Biosolids stabilized in constructed wetlands (CWs) may serve as an applicable organic amendment, although limited literature exists on their properties.

Morphodynamics and management challenges for beaches in modified estuaries and bays.

There is a relative lack of research, targeted models and tools to manage beaches in estuaries and bays (BEBs). Many estuaries and bays have been highly modified and urbanised, for example port developments and coastal revetments. This paper outlines the complications and opportunities for conserving and managing BEBs in modified estuaries.

Ozone enhances biological treatment of hydrothermal liquefaction aqueous stream from municipal sludge.

Hydrothermal liquefaction (HTL) is a promising alternative to anaerobic digestion for municipal sludge valorization due to biocrude oil and nutrient-dense hydrochar production, smaller footprint, enhanced micropollutant degradation, and minimized residual biosolids. However, integrating HTL into wastewater treatment plants necessitates on-site treatment of HTL aqueous, which is 80 % of byproducts by volume. HTL aqueous exhibits inhibition on downstream biological treatment due to high chemical oxygen demand (COD), total phenolics, ketones and nitrogen heterocyclics.

Groundwater denitrification dynamics and NO emissions across diverse cultivated land types in the Taihu lake region.

Groundwater denitrification is a vital biogeochemical process for maintaining environmental quality, yet its spatiotemporal variability and driving factors remain poorly understood. In this study, denitrification characteristics across three typical cultivated land types (rice‒wheat rotation fields, orchards, and vegetable fields) in the Taihu Lake region were quantified through measurements of the dissolved N and NO concentrations in groundwater. The findings revealed significantly higher average NO⁻-N, N, and NO concentrations in groundwater from rice-wheat rotation and vegetable fields than those in groundwater from orchards at the early stages of conversion from rice paddies.

Hybrid Binders Through Alkaline Activation of Fine Construction and Demolition Waste.

The use of construction and demolition waste (CDW) as an alternative binder to ordinary Portland cement presents a promising solution through alkaline activation. This study evaluates the physical, mechanical, and microstructural behaviour of pastes and mortars produced with CDW-specifically concrete (RH) and ceramic (RC) waste-activated with NaOH and NaSiO (SS) solutions. Mortars were prepared with NaOH/SS ratios of 0.

Potential sustained production of polyhydroxyalkanoate copolymers using cyanobacteria microbiomes.

The copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is considered one of the most promising PHA candidates for bioplastics production, exhibiting superior physical properties than the homopolymer poly(3-hydroxybutyrate) (PHB). In this study, for the first time, PHBV was successfully produced under non-sterile conditions with Synechocystis sp. and Synechococcus sp.

PHB in cyanobacteria: analyzing production through images processing and FT-IR techniques.

Cyanobacteria have gained significant attention in recent years due to their ability to produce a variety of valuable compounds. One such compound is polyhydroxybutyrate (PHB), a biodegradable polymer with immense potential in various industrial applications. Given that PHB is stored intracellularly, a dedicated process is needed to extract and measure the biopolymer content.

Global synthesis and regional insights for mainstreaming urban nature-based solutions.

Nature-based solutions (NbS) have emerged as a key strategy for sustainably addressing multiple urban challenges, with rapidly increasing knowledge production requiring synthesis to better understand whether and how NbS work in different social, ecological, economic, or governance contexts. Insights in this Perspective are drawn from a thematic review of 61 NbS review articles supported by an expert assessment of NbS knowledge in seven global regions to examine key challenges, fill gaps in Global South assessment, and provide insights for scaling up NbS for impact in cities. Eight NbS challenges emerged from our review of NbS reviews including conceptual, thematic, geographic, ecological, inclusivity, health, governance, and systems challenges.

Artificial intelligence based hyperspectral biomass estimator for cyanobacteria cultivation.

Hyperspectral imaging combined with machine learning offers an innovative approach for biomass monitoring at laboratory and industrial scale, but a proof-of-concept linking hyperspectral data to biomass prediction remains limited. This study fills that gap by creating a dataset with 205 biomass measurements and 450 hyperspectral images from three cyanobacteria-rich microbiomes. Data were acquired using a compact push-broom camera, followed by image preprocessing to extract spectral information for training three machine learning algorithms based on either spectral or image data.

A century of sediment metal contamination of Mar Menor, Europe's largest saltwater lagoon.

Coastal enclosed ecosystems, such as lagoons, are vulnerable to anthropogenic impacts because they favor the accumulation of contaminants from the surrounding watersheds, particularly in their sediments. Europe's largest saltwater lagoon, the Mar Menor (SE, Iberian Peninsula), is a highly impacted ecosystem and the first in the continent to be granted personhood rights. Based on a high-resolution spatial and temporal dataset, we present the historical reconstruction of metal contamination in this ecosystem during the last century.

On the limitations of closed-loop geothermal systems for electricity generation outside high-geothermal gradient fields.

Closed-Loop Geothermal Systems (CLGS) involve connecting the injection and production wells through several borehole-sized parallel laterals instead of circulating a working fluid through a fracture network. Companies have garnered millions of dollars in investments on the claim that CLGS is truly scalable for both heating and electricity generation purposes. We show that high flow rates in the laterals lead to a steep drop in production temperatures because of a rapid cooling of the rock matrix surrounding the wells.

Improving PHB production in cyanobacteria: Modeling the optimal light regime for growth.

The production of bioplastics, such as polyhydroxybutyrate (PHB), using cyanobacteria offers a sustainable alternative to conventional plastics. However, achieving economically viable production requires optimizing biomass growth. This study examined four growth models: Gompertz (empirical growth), Baranyi-Roberts (biologically dependent), Monod (nutrient dependent), and Aiba (irradiance dependent).

Fate of Exogenous Selenium in the Soil-Plant System: Se Accumulation, Translocation, and Effects on Growth in Vegetable, Legume, and Cereal Species.

Selenium (Se) is an essential micronutrient that is often deficient in human and animal diets. As primary dietary components, cereals, legumes, and vegetables present viable targets for Se biofortification. However, systematic comparisons of Se behavior in the soil environment and across diverse crops remain limited.

Exploring the biostimulant potential of Scenedesmus sp. grown in wastewater: impacts on plant growth and photosynthetic activity of lettuce.

Microalgae can produce different biostimulant compounds, which might increase plant growth and make them tolerant to abiotic stress. The aim of this study is to assess the biostimulant capacity of microalgal biomass cultivated in wastewater. Microalgae biomass was obtained in a high rate algae pond treating urban wastewater and then harvested and lyophilized.

Experimental Study on the Structural Performance of Glass-Fiber-Reinforced Concrete Slabs Reinforced with Glass-Fiber-Reinforced Polymer (GFRP) Bars: A Sustainable Alternative to Steel in Challenging Environments.

The inherent brittleness of glass-fiber-reinforced polymer (GFRP) bars limits their structural applicability despite their corrosion resistance and lightweight properties. This study addresses the critical challenge of enhancing the ductility and crack resistance of GFRP-reinforced systems while maintaining their environmental resilience. Through experimental evaluation, GFRC slabs reinforced with GFRP bars are systematically compared to steel-reinforced GFRC slabs and non-bar-reinforced SFRC slabs under bending loads.

Characterization of Bituminous Materials and Their Resistance to Fatigue Cracking by Dissipated Energy in Cyclic Tests: EBADE Test.

This paper presents the application of the same type of cyclic strain sweep test, the EBADE test, in the characterization of bitumens and mixes. This test employs a consistent methodology and set of parameters-namely, breaking stress, tenacity and dissipated energy at failure-to evaluate fatigue failure resistance in both materials. These parameters are intrinsically interrelated, and based on this relationship, the EBADE diagram was developed to establish a quantitative scale for resistance, ductility and tenacity.

Carotenoids and biogas recovery from microalgae treating wastewater.

This study evaluated the potential of microalgal biomass grown in wastewater for carotenoid and biogas recovery in a biorefinery approach. Microalgal biomass was harvested from two pilot high rate algal ponds treating urban wastewater with hydraulic retention times (HRTs) of 8 and 6 days. The maximum carotenoid content in harvested biomass was 4 mg·g total suspended solids (TSS) with a HRT of 8 days, while it reached around 1.

Microalgae wastewater treatment: Pharmaceutical removal and biomass valorization.

The growing global challenges of wastewater treatment, resource recovery, and environmental pollution are critical in addressing the sustainability of both urban and agricultural systems. Conventional treatment methods often fail to remove pharmaceutical pollutants effectively, which can lead to serious environmental and health concerns. As an alternative, microalgae-based systems have shown potential for addressing wastewater treatment while recovering valuable nutrients.

Exploring simultaneous production of poly(3-hydroxybutyrate) and exopolysaccharides in cyanobacteria-rich microbiomes.

The aim of this study was to explore the viability of the dual production of poly(3-hydroxybutyrate) (PHB) and exopolysaccharides (EPS) by seven microbiomes rich in cyanobacteria. Our initial experiments involved to screen for EPS-producing candidates and examine the impact of salinity and acetate on EPS synthesis. Salinity's known influence on EPS production and acetate's role in enhancing PHB production guided our parameter selection.

Research on Curing Reaction Kinetics and Curing Process of Nitrate Ester Plasticized Polyether (NEPE) Propellants.

The casting-curing process is a common technology for manufacturing the Nitrate Ester Plasticized Polyether (NEPE) propellants. The curing process involves a coupled thermal-chemical reaction of the adhesive systems of propellant, which influences the curing stage. Using GID 16 software, a propellant grain curing simulation model was conducted.

Combining seepage meters and amphibious electric resistivity tomography to investigate pathways of submarine groundwater discharge.

Submarine groundwater discharge (SGD) plays a pivotal role in coastal biogeochemistry, yet it is still challenging to accurately quantify water and solute fluxes driven by this process due to its complex hydrogeological dynamic. This work aims to improve the methods to identify and independently quantify different pathways of SGD by combining direct measurements through seepage meters and Amphibious Electrical Resistivity Tomography (AERT) at a heterogeneous karstic system in the Mediterranean Sea. The integrated approach identified and quantified distinct SGD pathways, including beach-face recirculation, focused discharge zones, submarine springs, and diffusive discharge, each uniquely influencing SGD dynamics.

Environmental and economic benefits of using microalgae grown in wastewater as biofertilizer for lettuce cultivation.

Mineral fertilizers play a significant role in environmental pollution of soil and water bodies, prompting the scientific community to search for more sustainable alternatives. However, environmentally-friendly organic options use to be more expensive. The objective of this study was to assess the potential environmental and economic impacts of biofertilizer from microalgae grown in wastewater, in a circular economy approach.

Cyanobacteria microbiomes for bioplastic production: Critical review of key factors and challenges in scaling from laboratory to industry set-ups.

Cyanobacteria are photoautotrophic microorganisms capable of accumulating polyhydroxybutyrate (PHB). A novel approach for PHB production involves the exploration of cyanobacterial microbiomes, potentially reducing costs through non-sterile cultivation with non-pure substrates. Although still in its early stages, this approach shows promise for high yields and sustained synthesis.

Application of digestate from low-tech digesters for degraded soil restoration: Effects on soil fertility and carbon sequestration.

The application of digestate to soil represents a common practice for its recycling, but its application to degraded lands to achieve their restoration and sequester organic C into the soil is still almost unexplored. In this context, this study describes a first attempt to use digestate from a low-tech digester for degraded soil restoration in Colombia. An experimental site (2700 m) previously subjected to intensive mono-cultivation was treated with digestate application for 4 months (40 Mg ha dry weight).

Durable Structural Recycled Concrete for Different Exposure Environments.

In this work, the influence of limited percentages of coarse (CRCA) and fine (FRCA) recycled concrete aggregates (Type A recycled aggregates) on the durability properties of structural concrete was analyzed. Concretes were designed using 50% and 60% CRCA with simultaneous additions of 0%, 10%, and 20% FRCA and different types of cement (CEM II/AL 42.5 R, CEM II/AS 42.