Environments

19 pages, 6398 KB

Open AccessArticle

Spatial and Multivariate Analysis of Groundwater Hydrochemistry in the Solana Aquifer, SE Spain

by Víctor Sala-Sala, José Miguel Andreu, Ana Pérez-Gimeno, Manuel M. Jordán, Jose Navarro-Pedreño and María Belén Almendro-Candel

Environments 2025, 12(9), 323; https://doi.org/10.3390/environments12090323 (registering DOI) - 12 Sep 2025

Abstract

The Solana aquifer is located in the South-East of the Iberian Peninsula and forms part of the Villena-Benejama groundwater body. It is a limestone and dolomite aquifer that has historically been considered overexploited due to intensive agriculture and urban use. Despite this, the [...] Read more.

The Solana aquifer is located in the South-East of the Iberian Peninsula and forms part of the Villena-Benejama groundwater body. It is a limestone and dolomite aquifer that has historically been considered overexploited due to intensive agriculture and urban use. Despite this, the quality of the water has remained stable over time. This study analyses the spatial and temporal variability within the aquifer and identifies the controlling processes. Chemical analyses were conducted on samples taken from 26 wells in July 2024 and February 2025. The results reveal a predominant calcium carbonate facies with minimal seasonal variation. However, sulphate-chloride water was found in the South-Western sector, which is associated with the dissolution of evaporitic materials from the Triassic Keuper. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) identified two processes: a salinity gradient linked to lithology, and a second process related to bicarbonates and nitrates, indicating potential nitrate inputs in the eastern half of the aquifer. HCA differentiates four clusters: one highly mineralised group located in the south-western sector near Triassic outcrops, two intermediate groups with slight differences in composition and distribution, and a fourth group with the lowest mineralisation located on the Southern flank of the Solana range. Full article

(This article belongs to the Special Issue Research Progress in Groundwater Contamination and Treatment)

► Show Figures

Figure 1

36 pages, 2822 KB

Open AccessArticle

The Role of Phytoplankton in the Assessment of the Ecological State of the Floodplain Lakes of the Irtysh River, Kazakhstan

by Elena Krupa, Yerkezhan Argynbayeva, Sophia Barinova and Sophia Romanova

Environments 2025, 12(9), 322; https://doi.org/10.3390/environments12090322 (registering DOI) - 12 Sep 2025

Abstract

Floodplain lakes play a significant role in maintaining biological diversity and providing a food base for aquatic organisms. In 2023–2024, for the first time, we studied phytoplankton of five floodplain lakes of the transboundary Irtysh River in Kazakhstan. A total of 149 species [...] Read more.

Floodplain lakes play a significant role in maintaining biological diversity and providing a food base for aquatic organisms. In 2023–2024, for the first time, we studied phytoplankton of five floodplain lakes of the transboundary Irtysh River in Kazakhstan. A total of 149 species and forms of planktonic algae were recorded, with a low level of similarity between the lakes. The ratio of indicator species (predominance of eutraphents and meso-eutraphents), abundance (3301.6–168,961.1 thou. cells L^‒1), biomass (2.41–83.67 mg L^‒1) of phytoplankton communities, and composition of dominant phyla and species (Cyanobacteria: Microcystis pulverea, M. aeruginosa, Aphanizomenon flos-aquae; Chlorophyta: Volvox globator; Dinoflagellata: Ceratium hirundinella and others) testified to a high level of organic pollution of floodplain lakes. Chemical variables (nitrogen compound content, PI) supported this conclusion. Analysis of the RDA revealed that the biomass of Cyanobacteria was controlled by nitrate nitrogen, while phosphates controlled that of Chlorophyta. The applied integrated approach showed an improvement in the trophic status of lakes in a high-water year and can be useful in assessing the ecological state of aquatic ecosystems in other regions. Full article

(This article belongs to the Special Issue Environmental Risk Assessment of Aquatic Environments)

19 pages, 1939 KB

Open AccessArticle

Genotoxic Effects of Water in Aquatic Ecosystems with Varying Cyanobacterial Abundance Assessed Using the Allium Test

by Svetlana Kurbatova, Dmitry Pesnya, Andrey Sharov, Igor Yershov, Ekaterina Chernova, Roman Fedorov, Ivan Semadeni and Galina Shurganova

Environments 2025, 12(9), 321; https://doi.org/10.3390/environments12090321 - 12 Sep 2025

Abstract

Cyanobacterial blooms in aquatic ecosystems are a major global environmental concern. While the mutagenic and mitosis-disrupting properties of isolated cyanobacterial toxins are well documented, evidence of cytogenotoxic effects resulting from cyanobacterial blooms in natural aquatic ecosystems remains limited. In this study, water genotoxicity [...] Read more.

Cyanobacterial blooms in aquatic ecosystems are a major global environmental concern. While the mutagenic and mitosis-disrupting properties of isolated cyanobacterial toxins are well documented, evidence of cytogenotoxic effects resulting from cyanobacterial blooms in natural aquatic ecosystems remains limited. In this study, water genotoxicity was evaluated in microcosms simulating cyanobacterial blooms of varying abundance. In microcosms with initially high cyanobacterial abundances (4.6 × 10⁷ and 2.2 × 10⁷ cells L⁻¹) and biomass (58 mg L⁻¹ and 20 mg L⁻¹), significant toxic, cytotoxic, mitosis-disrupting, and mutagenic effects were observed: root elongation was inhibited by up to 49.6% (Day 1), the mitotic index decreased by ~33% (Treatment I, Day 42) vs. Control, and total chromosomal aberrations and lagging chromosomes increased by ~2.5-fold on Day 1 (Treatment I) and ~4.7-fold on Day 42 (Treatment I) vs. Control; micronuclei increased ~10-fold on Day 42 in Treatment I and II. In microcosms with lower cyanobacterial abundance (1.2 × 10⁷ cells L⁻¹) and biomass (9 mg L⁻¹), significant reductions were observed only in root growth and in the mitotic index compared with Control. Future research should aim to identify a broader spectrum of cyanobacterial toxins and to investigate their environmental fate and persistence in aquatic ecosystems, particularly since genotoxic effects were detected even during the post-bloom period: on Day 42 extracellular microcystins in water were <LOQ in Treatments I and III (and 0.025 µg L⁻¹ in Treatment II), yet chromosome lagging and micronuclei remained elevated. The observed genotoxicity associated with cyanobacterial metabolites underscores the need for thorough risk assessments of cyanobacterial blooms in aquatic environments. Full article

(This article belongs to the Special Issue Environmental Risk Assessment of Aquatic Environments)

► Show Figures

Graphical abstract

24 pages, 2567 KB

Open AccessArticle

How Altitude Affects the Phenolic Potential of the Grapes of cv. ‘Fokiano’ (Vitis vinifera L.) on Ikaria Island

by Ioannis Daskalakis, Maritina Stavrakaki, Katerina Vardaka, Stavroula Nikolaou, Stefania Koukoufiki, Theodora Giannakou, Despoina Bouza and Katerina Biniari

Environments 2025, 12(9), 320; https://doi.org/10.3390/environments12090320 - 11 Sep 2025

Abstract

Climate is one of the main factors that significantly impacts the terroir of vineyards by directly affecting vine growth, yield, and berry composition, which, in turn, are key to the quality characteristics of the wines produced. Climate change poses new challenges, especially in [...] Read more.

Climate is one of the main factors that significantly impacts the terroir of vineyards by directly affecting vine growth, yield, and berry composition, which, in turn, are key to the quality characteristics of the wines produced. Climate change poses new challenges, especially in insular regions where changing grapevine varieties is limited due to Protected Designation of Origin (PDO) rules. Cultivating vines at higher altitudes may prove to be a potential solution. This study aimed to investigate the phenolic potential of the skins and seeds of cv. ‘Fokiano’, cultivated at two different altitudes, namely, 200 m and 800 m, on the Greek island of Ikaria, during 2019–2021. The results showed that grapes from 200 m exhibited higher values for weight, length, and width, while those from 800 m exhibited higher berry water content and higher skin-to-grape ratios. In addition, higher values of anthocyanins, enhancing the grapes’ color and phenolic composition, were recorded in grapes harvested at 800 m. It is, therefore, evident that higher altitudes can help grapes exhibit higher anthocyanin content and titratable acidity. Consequently, the choice of an altitude can counteract the phenomenon of early ripening caused by climate change. Adaptation strategies based on the present study’s observations may constitute viable long-term recommendations for vineyard establishment, especially in insular regions where it is not possible to move geographically to northern latitudes. Full article

► Show Figures

Figure 1

14 pages, 1259 KB

Open AccessArticle

Carbon Dioxide Bio-Capture and Organic Carbon Production in Two Microalgae Strains Grown Under Different CO₂ Conditions

by David A. Gabrielyan, Maria A. Sinetova, Grigoriy A. Savinykh, Elena V. Zadneprovskaya, Maria A. Goncharova, Bogdan Yu. Bulychev, Ekaterina A. Flerova and Nikolay V. Lobus

Environments 2025, 12(9), 319; https://doi.org/10.3390/environments12090319 - 11 Sep 2025

Viewed by 29

Abstract

The need to reduce anthropogenic greenhouse gas emissions drives the development of innovative carbon dioxide capture technologies. Microalgae-based biotechnologies represent a promising approach in this field. In this study, we evaluated the CO₂ assimilation efficiency of two novel microalgae strains, Desmodesmus armatus [...] Read more.

The need to reduce anthropogenic greenhouse gas emissions drives the development of innovative carbon dioxide capture technologies. Microalgae-based biotechnologies represent a promising approach in this field. In this study, we evaluated the CO₂ assimilation efficiency of two novel microalgae strains, Desmodesmus armatus ARC-06 and Tribonema minus ARC-10, under low (0.04%) and high (1.5%) CO₂ conditions in a periodic cultivation system. The two strains exhibited distinct CO₂ adaptation strategies. D. armatus demonstrated higher tolerance to low CO₂ conditions, whereas T. minus showed superior performance under elevated CO₂. Although elevated CO₂ stimulated growth in both strains, their carbon dioxide sequestration efficiency (CDSE) differed markedly. The maximum CDSE was significantly higher in T. minus (30.0 ± 1.52%) compared to D. armatus (16.5 ± 1.12%). Similarly, the average CDSE over the cultivation period was greater in T. minus (19.1 ± 2.18%) than in D. armatus (11.8 ± 1.45%). These results underscore the importance of bioprospecting for novel microalgae strains, and the need for further research to develop efficient biological CO₂ sequestration methods. Full article

(This article belongs to the Topic Greenhouse Gas Emission Reductions and Carbon Sequestration in Agriculture)

► Show Figures

Figure 1

10 pages, 913 KB

Open AccessArticle

Combined Exposure to Polyethylene Microplastics and Copper Affects Growth and Antioxidant Responses in Rice Seedlings

by Ziwen Hao, Ziyang Li, Zhangdong Wei, Lin Wang and Ming Xu

Environments 2025, 12(9), 318; https://doi.org/10.3390/environments12090318 - 10 Sep 2025

Viewed by 174

Abstract

The co-existence of polyethylene microplastics (PE-MPs) and heavy metals in aquatic ecosystems poses emerging threats to crop systems, yet their combined phytotoxic effects remain insufficiently understood. In this study, hydroponic rice (Oryza sativa) seedlings were exposed to PE-MPs (50 mg/L) and [...] Read more.

The co-existence of polyethylene microplastics (PE-MPs) and heavy metals in aquatic ecosystems poses emerging threats to crop systems, yet their combined phytotoxic effects remain insufficiently understood. In this study, hydroponic rice (Oryza sativa) seedlings were exposed to PE-MPs (50 mg/L) and copper (Cu, 20 mg/L) individually and in combination. The results showed that PE-MPs alone had no significant impact on shoot or root elongation, while Cu exposure slightly reduced root length (from 6.2 cm in the control to 5.8 cm) without affecting shoot growth (~37 cm). Combined PE+Cu treatment resulted in intermediate biomass values, suggesting that microplastics partially mitigated but did not eliminate Cu toxicity. Antioxidant responses displayed organ specificity: shoot peroxidase (POD) activity dropped sharply from >10,000 U/g in the control to ~1200 U/g under Cu exposure, while root POD activity decreased from >11,000 U/g in the control to ~1500 U/g under combined exposure. Cu accumulation was markedly elevated under co-exposure, reaching ~450 mg/kg, about 25% higher than Cu alone and more than 12 times greater than control. These findings demonstrate that PE-MPs can enhance Cu bioavailability and uptake, thereby intensifying oxidative stress in roots while altering shoot defense responses. The study highlights the ecological risks of microplastic–metal co-contamination in agricultural systems and underscores the need for further investigation into long-term impacts on crop productivity and food safety. Full article

► Show Figures

Figure 1

22 pages, 1462 KB

Open AccessArticle

Analysis of Selected Potentially Harmful Metal Elements in Soils and Vegetables in Gold Mining Region: Case Study Evaluated in Kenya, Africa

by John M. Macharia, Ngure Veronica, Lareen Wangare and Raposa L. Bence

Environments 2025, 12(9), 317; https://doi.org/10.3390/environments12090317 - 9 Sep 2025

Viewed by 333

Abstract

This study aimed to assess heavy metal and associated trace element contamination in soils and vegetables from artisanal gold mining areas in Migori County, Kenya. Soil concentrations were markedly elevated, with Pb (15.4–706 mg/kg), Cd (0.14–6.07 mg/kg), Ni (0.2–33.4 mg/kg), Cr (11.9–119.3 mg/kg), [...] Read more.

This study aimed to assess heavy metal and associated trace element contamination in soils and vegetables from artisanal gold mining areas in Migori County, Kenya. Soil concentrations were markedly elevated, with Pb (15.4–706 mg/kg), Cd (0.14–6.07 mg/kg), Ni (0.2–33.4 mg/kg), Cr (11.9–119.3 mg/kg), As (0.1–37.4 mg/kg), Zn (38–1454 mg/kg), Se (0.1–0.8 mg/kg), and Hg (0.51–1830 mg/kg) all exceeding international guideline values. Corresponding vegetable concentrations were as follows: Pb (0.17–71.3 mg/kg), Ni (0.2–111 mg/kg), Cr (2.4–244 mg/kg), As (1.2–399 mg/kg), Hg (0.22–35 mg/kg), Zn (11.2–67.4 mg/kg), and Se (0.1–5.7 mg/kg). Brassica oleracea var. capitata (cabbage) exhibited the highest uptake, while Amaranthus hybridus (smooth pigweed) showed the lowest. Estimated daily intake (EDI) values for Pb, Ni, Cr, As, Zn, and Hg exceeded FAO/WHO limits, with hazard quotients (HQ) > 1 for all metals and hazard index (HI) values between 15.6 and 30.4, indicating significant non-carcinogenic and carcinogenic risks. These findings highlight severe contamination linked to geological background and mining activity, underscoring the urgent need for regular monitoring and mitigation to protect food safety and public health. Full article

► Show Figures

Figure 1

17 pages, 2631 KB

Open AccessArticle

Adsorption of Phosphates from Wastewater Using MgAlFe-Layered Double Hydroxides

by Oanamari Daniela Orbuleţ, Liliana Bobirică, Mirela Enache (Cişmaşu), Ramona Cornelia Pațac, Magdalena Bosomoiu and Cristina Modrogan

Environments 2025, 12(9), 316; https://doi.org/10.3390/environments12090316 - 7 Sep 2025

Viewed by 472

Abstract

Phosphates pollution, primarily from agricultural runoff and wastewater discharge, is a major contributor to water eutrophication, adversely affecting aquatic ecosystems. This study reports the synthesis, characterization, and phosphates adsorption performance of a MgAlFe-layered double hydroxide (MgAlFe-LDH) with a 2:1:1 cationic ratio. The material [...] Read more.

Phosphates pollution, primarily from agricultural runoff and wastewater discharge, is a major contributor to water eutrophication, adversely affecting aquatic ecosystems. This study reports the synthesis, characterization, and phosphates adsorption performance of a MgAlFe-layered double hydroxide (MgAlFe-LDH) with a 2:1:1 cationic ratio. The material was prepared via co-precipitation and characterized using digital microscopy, XRD, BET, XPS, and FTIR. Adsorption experiments were conducted at pH 3 and 9 to investigate equilibrium, kinetics, and reusability. The MgAlFe-LDH exhibited a high maximum adsorption capacity (q_max ≈ 215 mg/g) largely independent of pH, with adsorption well described by the Langmuir model. Kinetic studies revealed a pseudo-first-order mechanism, indicating that adsorption is dominated by surface diffusion and electrostatic interactions. Phosphate removal occurs through a dual mechanism involving rapid electrostatic attraction at protonated surface sites and slower ion exchange in the LDH interlayers. The material retained over 75% of its adsorption capacity after five consecutive adsorption–desorption cycles, highlighting its potential for sustainable phosphate recovery. Overall, the MgAlFe-LDH represents a promising, reusable adsorbent for phosphorus removal from wastewater, supporting circular economy strategies. Full article

(This article belongs to the Special Issue Advanced Technologies of Water and Wastewater Treatment (2nd Edition))

► Show Figures

Figure 1

3 pages, 147 KB

Open AccessEditorial

Microplastics Pollution in Aquatic Ecosystems: Challenges and Perspectives

by Farhan R. Khan, Charles Rolsky, Ana I. Catarino and Varun Kelkar

Environments 2025, 12(9), 315; https://doi.org/10.3390/environments12090315 - 5 Sep 2025

Viewed by 355

Abstract

Over the last 20 years, microplastics have emerged as a grave environmental concern owing to their ubiquitous presence and demonstrable toxic effects [...] Full article

(This article belongs to the Special Issue Microplastics Pollution in Aquatic Ecosystems: Challenges and Perspectives)

19 pages, 1888 KB

Open AccessArticle

Adsorption of Phenol from Aqueous Solution Utilizing Activated Carbon Prepared from Catha edulis Stem

by Meseret Dawit Teweldebrihan, Mikiyas Abewaa Gnaro and Megersa Olumana Dinka

Environments 2025, 12(9), 314; https://doi.org/10.3390/environments12090314 - 5 Sep 2025

Viewed by 454

Abstract

Phenol and its derivatives in water and wastewater are highly toxic and challenging to degrade, posing serious environmental and health risks. Therefore, this research focuses on the removal of phenol from aqueous solutions using activated carbon made from Catha edulis stems. The activation [...] Read more.

Phenol and its derivatives in water and wastewater are highly toxic and challenging to degrade, posing serious environmental and health risks. Therefore, this research focuses on the removal of phenol from aqueous solutions using activated carbon made from Catha edulis stems. The activation process involved impregnating the Catha edulis stems with phosphoric acid followed by thermal treatment at 500 °C for 2 h. The resulting adsorbent was extensively characterized using various techniques, including Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) surface area analysis, and proximate analysis. Batch adsorption experiments were designed using a full factorial approach with four factors at two levels, resulting in 16 different experimental conditions. The characterization results showed that the activated carbon has a high surface area of 1323 m²/g, a porous and heterogeneous structure, and an amorphous surface with multiple functional groups. Under optimal conditions of pH 2, a contact time of 60 min, an adsorbent dosage of 0.1 g/100 mL, and an initial phenol concentration of 100 mg/L, the adsorbent achieved a phenol removal efficiency of 99.9%. Isotherm and kinetics analyses revealed that phenol adsorption fits the Langmuir model and pseudo-second-order kinetics, indicating a uniform interaction and chemisorptive process. This study highlights the effectiveness of Catha edulis stem-based activated carbon as a promising material for phenol removal in water treatment applications. Full article

(This article belongs to the Special Issue Advanced Technologies of Water and Wastewater Treatment (2nd Edition))

► Show Figures

Figure 1

26 pages, 6536 KB

Open AccessArticle

Biogenic CO₂, CH₄, and N₂O Emissions from Abalone Culture in Tidal Ponds

by Yi-Jung Chen, Wen-Chen Chou, Hsiao-Chun Tseng, Ruei-Feng Shiu, Meng-Chou Lee, Fan-Hua Nan and Han-Yang Yeh

Environments 2025, 12(9), 313; https://doi.org/10.3390/environments12090313 - 4 Sep 2025

Viewed by 539

Abstract

Abalone is among the most highly prized seafoods, valued for its delicate flavor and texture. As abalone aquaculture continues to expand, addressing its environmental impacts has become increasingly important. Although aquaculture is recognized as a contributor to greenhouse gas (GHG) emissions, the specific [...] Read more.

Abalone is among the most highly prized seafoods, valued for its delicate flavor and texture. As abalone aquaculture continues to expand, addressing its environmental impacts has become increasingly important. Although aquaculture is recognized as a contributor to greenhouse gas (GHG) emissions, the specific mechanisms and pathways of GHG emissions—particularly in abalone farming—remain poorly understood. To clarify the patterns and drivers of GHG emissions in abalone (Haliotis discus) culture systems, this study was conducted in three aquaculture ponds located in Gongliao District, New Taipei City, Taiwan. We measured CO₂, CH₄, and N₂O fluxes along with key environmental parameters to assess variation across sampling locations, times, and seasons. The results showed that sampling time had no significant effect on GHG flux variations, whereas seasonal changes influenced all three gases, and sampling location significantly affected N₂O flux only. During the culture period, average fluxes were 2.19 ± 10.83 mmol m⁻² day⁻¹ for CO₂, 2.11 ± 2.81 µmol m⁻² day⁻¹ for CH₄, and 1.65 ± 2.73 µmol m⁻² day⁻¹ for N₂O, indicating that the abalone ponds served as net sources of these GHGs. When converted to CO₂-equivalents (CO₂-eq), the total average CO₂-eq flux from the ponds was 0.02 ± 0.09 mg CO₂-eq m⁻² day⁻¹, calculated using global warming potential (GWP₂₀ and GWP₁₀₀) metrics. This study provides the first comprehensive assessment of GHG emissions in abalone pond systems and offers valuable insights into their emission dynamics. The findings contribute to the scientific basis needed to improve aquaculture GHG inventories. Full article

► Show Figures

Figure 1

16 pages, 530 KB

Open AccessArticle

Investigating the Cosmic and Solar Drivers of Stratospheric ⁷Be Variability

by Alessandro Rizzo, Giuseppe Antonacci, Massimo Astarita, Enrico Maria Borra, Luca Ciciani, Nadia di Marco, Giovanna la Notte, Patrizio Ripesi, Luciano Sperandio, Ignazio Vilardi and Francesca Zazzaron

Environments 2025, 12(9), 312; https://doi.org/10.3390/environments12090312 - 4 Sep 2025

Viewed by 442

Abstract

Space weather exerts a significant influence on the Earth’s atmosphere, driving a variety of physical processes, including the production of cosmogenic radionuclides. Among these, ⁷Be is a naturally occurring radionuclide formed through spallation reactions induced by cosmic-ray showers interacting with atmospheric constituents, [...] Read more.

Space weather exerts a significant influence on the Earth’s atmosphere, driving a variety of physical processes, including the production of cosmogenic radionuclides. Among these, ⁷Be is a naturally occurring radionuclide formed through spallation reactions induced by cosmic-ray showers interacting with atmospheric constituents, primarily oxygen and nitrogen. Over long timescales, the atmospheric concentration of ⁷Be exhibits a direct correlation with the cosmic-ray flux reaching the Earth and an inverse correlation with solar activity, which modulates this flux via variations of the heliosphere. The large availability of ⁷Be concentration data, resulting from its use as a natural tracer employed in atmospheric transport studies and in monitoring the fallout from radiological incidents such as the Chernobyl disaster, can also be exploited to investigate the impact of space weather conditions on the terrestrial atmosphere and related geophysical processes. The present study analyzes a long-term dataset of monthly ⁷Be activity concentrations in air samples collected at ground level since 1987 at the ENEA Casaccia Research Center in Rome, Italy. In particular, the linear correlation of this time series with the galactic cosmic ray flux on Earth and solar activity have been investigated. Data from a ground-based neutron monitor and sunspot numbers have been used as proxies for galactic cosmic rays and solar activity, respectively. A centered running-mean low-pass filter was applied to the monthly ⁷Be time series to extract its low-frequency component associated with cosmic drivers, which is partially hidden by high-frequency modulations induced by atmospheric dynamics. For Solar Cycles 22, 23, 24, and partially 25, the analysis shows that a substantial portion of the relationship between stratospheric ⁷Be concentrations and cosmic drivers is captured by linear correlation. Within a statistically consistent framework, the evidence supports a correlation between ⁷Be and cosmic drivers consistent with solar-cycle variability. The ⁷Be radionuclide can therefore be regarded as a reliable atmospheric tracer of cosmic-ray variability and, indirectly, of solar modulation. Full article

► Show Figures

Figure 1

52 pages, 2983 KB

Open AccessSystematic Review

Niobium-Based Catalysts in Advanced Oxidation Processes: A Systematic Review of Mechanisms, Material Engineering, and Environmental Applications

by Michel Z. Fidelis, Julia Faria, William Santacruz, Thays S. Lima, Giane G. Lenzi and Artur J. Motheo

Environments 2025, 12(9), 311; https://doi.org/10.3390/environments12090311 - 4 Sep 2025

Viewed by 640

Abstract

Water contamination by emerging pollutants poses a significant environmental challenge, demanding innovative treatment technologies beyond conventional methods. Advanced oxidation processes (AOPs) utilizing niobium-based catalysts, particularly niobium oxide (Nb₂O₅) and its modified forms, are prominent due to their high chemical [...] Read more.

Water contamination by emerging pollutants poses a significant environmental challenge, demanding innovative treatment technologies beyond conventional methods. Advanced oxidation processes (AOPs) utilizing niobium-based catalysts, particularly niobium oxide (Nb₂O₅) and its modified forms, are prominent due to their high chemical stability, effective reactive oxygen species (ROS) generation, and versatility. This review systematically examines recent advancements in Nb₂O₅-based catalysts across various AOPs, including heterogeneous photocatalysis, electrocatalysis, and Fenton-like reactions, highlighting their mechanisms, material modifications, and performance. Following PRISMA and InOrdinatio guidelines, 381 papers were selected for this synthesis. The main findings indicate that niobium incorporation enhances pollutant degradation by extending light absorption, reducing electron–hole recombination, and increasing ROS generation. Structural modifications such as crystalline phase tuning, defect engineering, and the formation of heterostructures further amplify catalytic efficiency and stability. These catalysts demonstrate considerable potential for water treatment, effectively degrading a broad range of persistent contaminants such as dyes, pharmaceuticals, pesticides, and personal care products. This review underscores the environmental benefits and practical relevance of Nb₂O₅-based systems, identifying critical areas for future research to advance sustainable water remediation technologies. Full article

(This article belongs to the Special Issue Advanced Research on Micropollutants in Water, 2nd Edition)

► Show Figures

Graphical abstract

26 pages, 2939 KB

Open AccessArticle

Finding Common Climate Action Among Contested Worldviews: Stakeholder-Informed Approaches in Austria

by Claire Cambardella, Chase Skouge, Christian Gulas, Andrea Werdenigg, Harald Katzmair and Brian D. Fath

Environments 2025, 12(9), 310; https://doi.org/10.3390/environments12090310 - 3 Sep 2025

Viewed by 550

Abstract

Our goal was to identify and understand perspectives of different stakeholders in the field of climate policy and test a process of co-creative policy development to support the implementation of climate protection measures. As the severity of climate change grows globally, perceptions of [...] Read more.

Our goal was to identify and understand perspectives of different stakeholders in the field of climate policy and test a process of co-creative policy development to support the implementation of climate protection measures. As the severity of climate change grows globally, perceptions of climate science and climate-based policy have become increasingly polarized. The one-solution consensus or compromise that has encapsulated environmental policymaking has proven insufficient or unable to address accurately or efficiently the climate issue. Because climate change is often described as a wicked problem (multiple causes, widespread impacts, uncertain outcomes, and an array of potential solutions), a clumsy solution that incorporates ideas and actions representative of varied and divergent worldviews is best suited to address it. This study used the Theory of Plural Rationality, which uses a two-dimensional spectrum to identify four interdependent worldviews as well as a fifth autonomous perspective to define the differing perspectives in the field of climate policy in Austria. Stakeholder inputs regarding general worldviews, climate change, and climate policy were evaluated to identify agreeable actions representative of the multiple perspectives. Thus, we developed and tested a co-creative process for developing clumsy solutions. This study concludes that while an ideological consensus is unlikely, agreement is more likely to occur on the practical level of concrete actions (albeit perhaps for different reasons). Findings suggested that creating an ecological tax reform was an acceptable policy action to diverse stakeholders. Furthermore, the study illuminated that the government is perceived to have the most potential influence on climate protection policy and acts as a key “broker”, or linkage, between other approaches that are perceived to be more actualized but less impactful. Full article

► Show Figures

Figure 1

17 pages, 3089 KB

Open AccessArticle

Systematic Study of CDOM in the Volga River Basin Using EEM-PARAFAC

by Anastasia N. Drozdova, Aleksandr A. Molkov, Ivan A. Kapustin, Alexey V. Ermoshkin, George V. Leshchev, Ivan N. Krylov and Timur A. Labutin

Environments 2025, 12(9), 309; https://doi.org/10.3390/environments12090309 - 2 Sep 2025

Viewed by 526

Abstract

This manuscript continues a series of papers devoted to the study of bio-optical characteristics of the Volga River waters in the context of development of regional bio-optical models. A particularly weak point in this effort is the limited knowledge of dissolved organic matter [...] Read more.

This manuscript continues a series of papers devoted to the study of bio-optical characteristics of the Volga River waters in the context of development of regional bio-optical models. A particularly weak point in this effort is the limited knowledge of dissolved organic matter (DOM): its component composition, spectral absorption characteristics, and the lack of satellite-based assessment algorithms. Using excitation–emission matrix fluorescence spectroscopy, we examined the fluorescent fraction of DOM of surface water layer of the Volga River and its tributaries in the area from the Gorky Reservoir to the Volgograd Reservoir, a stretch spanning over 1500 km, in the period from May to September 2022–2024. Four fluorescent components were validated in parallel factor analysis. The ratio of fluorescent components was mostly stable, while their fluorescence intensities varied a lot. For example, the fluorescence intensity of the DOM of the Gorky Reservoir and the Kama River differed by more than 2.5-fold. The highest FDOM fluorescence was found in the Gorky Reservoir. Downstream, it decreased due to the inflow of the Oka and Kama rivers. The influence of small rivers such as Kerzhenets, Sundovik, Sura, and Vetluga was insignificant. It is demonstrated that neither conventional remote sensing techniques (LiDAR) plus in situ measurements of DOM with a probe nor DOM absorption at 440 nm allows probing all the fluorescent components, so their efficiency is determined by the correlation of fluorophore group content. Full article

► Show Figures

Figure 1

22 pages, 1433 KB

Open AccessReview

Harnessing Opportunities, Constraints, and Implications of Integrating Environmental Conservation with Sustainable Ruminant Production

by Chenaimoyo Lufutuko Faith Katiyatiya and Thobeka Ncanywa

Environments 2025, 12(9), 308; https://doi.org/10.3390/environments12090308 - 31 Aug 2025

Viewed by 713

Abstract

The growing demand for animal products exerts pressure on the livestock sector to increase production while minimizing its impact on the environment. The paper explored the impact of ruminant production systems on the environment and opportunities for enhancing production and environmental conservation. A [...] Read more.

The growing demand for animal products exerts pressure on the livestock sector to increase production while minimizing its impact on the environment. The paper explored the impact of ruminant production systems on the environment and opportunities for enhancing production and environmental conservation. A comprehensive review of literature on livestock production, animal nutrition, and environmental conservation was conducted. The review shows that the challenges of ruminant production on the ecosystem are centered around greenhouse gas emissions, land degradation, and water and feed resources. However, manipulation of animal feeding strategies, rotational grazing, precision farming, and integration of crop-livestock systems have the potential to enhance feed efficiency, reduce waste, improve animal health, and nutrition and reduce nitrogen and methane gas emissions. This will also improve manure management, soil health, and biodiversity, which are essential in climate resilience building and resource management by farmers. Development of effective strategies for enhancing animal nutrition and ruminant production while conserving the ecosystem is important. Full article

► Show Figures

Figure 1

26 pages, 1295 KB

Open AccessArticle

Adaptation and Bioremediation Efficiency of UV-Mutagenized Microalgae in Undiluted Agro-Industrial Effluents from Mexico

by Cesar E. Najar-Almanzor, Rosa Leonor González-Díaz, Tomás García-Cayuela and Danay Carrillo-Nieves

Environments 2025, 12(9), 307; https://doi.org/10.3390/environments12090307 - 31 Aug 2025

Viewed by 1196

Abstract

Microalgae offer a sustainable alternative for wastewater treatment by simultaneously removing pollutants and producing biomass of potential value. This study evaluated five species—Haematococcus pluvialis, Chlorella vulgaris, Chlamydomonas sp., Anabaena variabilis, and Scenedesmus sp.—in three undiluted food and beverage industry [...] Read more.

Microalgae offer a sustainable alternative for wastewater treatment by simultaneously removing pollutants and producing biomass of potential value. This study evaluated five species—Haematococcus pluvialis, Chlorella vulgaris, Chlamydomonas sp., Anabaena variabilis, and Scenedesmus sp.—in three undiluted food and beverage industry effluents from Mexico: nejayote (alkaline wastewater generated during corn nixtamalization for tortilla production), tequila vinasses (from tequila distillation), and cheese whey (from cheese making). Strains were adapted through UV mutagenesis and gradual acclimatization to grow without freshwater dilution. Bioremediation efficiency was assessed via reductions in chemical oxygen demand (COD), total nitrogen (TN), and total phosphates (TPO₄). C. vulgaris achieved complete TN and TPO₄ removal and 90.2% COD reduction in nejayote, while A. variabilis reached 81.7% COD and 79.3% TPO₄ removal in tequila vinasses. In cheese whey, C. vulgaris removed 55.5% COD, 53.0% TN, and 35.3% TPO₄. These results demonstrate the feasibility of microalgae-based systems for treating complex agro-industrial wastewaters, contributing to sustainable and circular wastewater management. Full article

(This article belongs to the Special Issue Environments: 10 Years of Science Together)

► Show Figures

Graphical abstract

18 pages, 1530 KB

Open AccessArticle

Decarbonization Potential of Alternative Fuels in Container Shipping: A Case Study of the EVER ALOT Vessel

by Mamdouh Elmallah, Ernesto Madariaga, José Agustín González Almeida, Shadi Alghaffari, Mahmoud A. Saadeldin, Nourhan I. Ghoneim and Mohamed Shouman

Environments 2025, 12(9), 306; https://doi.org/10.3390/environments12090306 - 31 Aug 2025

Viewed by 757

Abstract

Environmental emissions from the maritime sector, including CO₂, NO_x, and SO_x, contribute significantly to global air pollution and climate change. The International Maritime Organization (IMO) has set a target to reduce greenhouse gas emissions from international shipping [...] Read more.

Environmental emissions from the maritime sector, including CO₂, NO_x, and SO_x, contribute significantly to global air pollution and climate change. The International Maritime Organization (IMO) has set a target to reduce greenhouse gas emissions from international shipping to reach zero GHG by 2050 compared to 2008 levels. To meet these goals, the IMO strongly encourages the transition to alternative fuels, such as hydrogen, ammonia, and biofuels, as part of a broader decarbonization strategy. This study presents a comparative analysis of converting conventional diesel engines to dual-fuel systems utilizing alternative fuels such as methanol or natural gas. The methodology of this research is based on theoretical calculations to estimate various types of emissions produced by conventional marine fuels. These results are then compared with the emissions generated when using methanol and natural gas in dual-fuel engines. The analysis is conducted using the EVER ALOT container ship as a case study. The evaluation focuses on both environmental and economic aspects of engines operating in natural gas–diesel and methanol–diesel dual-fuel modes. The results show that using 89% natural gas in a dual fuel engine reduces nitrogen oxides (NO_x), sulfur oxides (SO_x), carbon dioxide (CO₂), particulate matter (PM), and carbon monoxide (CO) pollutions by 77.69%, 89.00%, 18.17%, 89.00%, and 30.51%, respectively, while the emissions percentage will be 77.78%, 91.00%, 54.67%, 91.00%, and 55.90%, in order, when using methanol as a dual fuel with percentage 91.00% Methanol. This study is significant as it highlights the potential of natural gas and methanol as viable alternative fuels for reducing harmful emissions in the maritime sector. The shift toward these cleaner fuels could play a crucial role in supporting the maritime industry’s transition to low-emission operations, aligning with global environmental regulations and sustainability goals. Full article

► Show Figures

Figure 1

17 pages, 3006 KB

Open AccessArticle

Plasticizers and Bisphenols in Sicilian Lagoon Bivalves, Water, and Sediments: Environmental Risk in Areas with Different Anthropogenic Pressure

by Giuseppa Di Bella, Federica Litrenta, Angela Giorgia Potortì, Salvatore Giacobbe, Vincenzo Nava, Davide Puntorieri, Ambrogina Albergamo and Vincenzo Lo Turco

Environments 2025, 12(9), 305; https://doi.org/10.3390/environments12090305 - 30 Aug 2025

Viewed by 560

Abstract

Plasticizers and bisphenols are contaminants of concern in the environment, particularly in aquatic ecosystems. Bivalve molluscs are effective bioindicators due to their benthic nature, their ability to filter water, and their capacity to bioaccumulate persistent pollutants. This study analyzes plasticizers and bisphenols in [...] Read more.

Plasticizers and bisphenols are contaminants of concern in the environment, particularly in aquatic ecosystems. Bivalve molluscs are effective bioindicators due to their benthic nature, their ability to filter water, and their capacity to bioaccumulate persistent pollutants. This study analyzes plasticizers and bisphenols in three native clam species (Ruditapes decussatus, Cerastoderma glaucum, and Polititapes aureus) from two Sicilian lagoons under different levels of anthropogenic pressure: the urbanized Capo Peloro lagoon (Ganzirri Lake) and the less impacted Oliveri–Tindari lagoon. The clams, together with water and sediment samples, were collected in winter 2023. Both groups of clams from the two sampling areas contained phthalates such as DMP, DEP, DiBP, and DEHP, as well as non-phthalate plasticizers such as DEHT, DBA, DEA, and DEHA. The sum of non-phthalate plasticizers (NPPs) was consistently higher than the sum of phthalates in all clam samples, confirming the emerging trend of NPPs. This trend was also observed in the water and sediment samples, regardless of the sampling area. The presence of structural analogues of bisphenol A (BPA) highlights the growing prevalence of BPA-like structures in aquatic environments. Given the increasing evidence of widespread and persistent contamination of aquatic environments by plasticizers and bisphenols, it is evident that these substances pose a significant threat to ecosystems and human health. Full article

(This article belongs to the Special Issue Environmental Risk Assessment of Aquatic Environments)

► Show Figures

Figure 1

12 pages, 2008 KB

Open AccessArticle

Metal Enrichment in Settleable Particulate Matter Associated with Air Pollution in the Andean City of Ecuador

by David del Pozo, Bryan Valle, Daniel Maza and Ángel Benítez

Environments 2025, 12(9), 304; https://doi.org/10.3390/environments12090304 - 30 Aug 2025

Viewed by 701

Abstract

Air pollution is one of the major environmental challenges worldwide. Settleable particulate matter (SPM), related to this environmental problem, contains metals capable of producing negative effects on human health (e.g., cardiovascular and respiratory illness). For this study, continuous monitoring was carried in the [...] Read more.

Air pollution is one of the major environmental challenges worldwide. Settleable particulate matter (SPM), related to this environmental problem, contains metals capable of producing negative effects on human health (e.g., cardiovascular and respiratory illness). For this study, continuous monitoring was carried in the urban city of Loja (Ecuador), where 10 points were distributed based on different land uses. Samples were collected on a monthly basis using a passive method, by means of samplers built based on the 502 Method. The gravimetric method was then used in the laboratory to determine the concentration of SPM. The inductively coupled plasma–optical emission spectroscopy (ICP-OES) technique was used to identify the presence of metals as such as Copper (Cu), Lead (Pb), Cobalt (Co), Cadmium (Cd), Chromium (Cr), Silver (Ag), Arsenic (As), and Mercury (Hg) in SPM. The results obtained showed that SPM and As differed significantly between land uses, but most metals showed significant differences in relation to temporal changes. Although 90% of the sampling points show SPM concentrations within the limits established by environmental regulations, some of the points exceed the World Health Organization (WHO) limit of 0.5 mg/cm². Finally, the temporal changes in more metals were clearly observed, probably because of increased combustion processes (vehicular traffic), with a higher percentage of metals clearly observed during the April and August months. Furthermore, the highest levels of vegetation burning in Loja province, including the surroundings of the city of Loja, occurred in August. This analysis provides essential data to guide environmental monitoring and air quality management strategies, aiming to reduce health risks from long-term exposure to metal-enriched particulate matter. Full article

► Show Figures

Figure 1

26 pages, 4464 KB

Open AccessArticle

Future Water Yield Projections Under Climate Change Using Optimized and Downscaled Models via the MIDAS Approach

by Mahdis Fallahi, Stacy A. C. Nelson, Peter Caldwell, Joseph P. Roise, Solomon Beyene and M. Nils Peterson

Environments 2025, 12(9), 303; https://doi.org/10.3390/environments12090303 - 29 Aug 2025

Viewed by 710

Abstract

Climate change significantly affects hydrological processes in forest ecosystems, particularly in sensitive coastal areas such as the Croatan National Forest (CNF) in North Carolina. Accurate projections of future water yield are essential for managing agriculture, forestry, and natural ecosystems. This study investigates the [...] Read more.

Climate change significantly affects hydrological processes in forest ecosystems, particularly in sensitive coastal areas such as the Croatan National Forest (CNF) in North Carolina. Accurate projections of future water yield are essential for managing agriculture, forestry, and natural ecosystems. This study investigates the potential impacts of climate change on water yield using a combination of statistical downscaling and machine learning. Two downscaling methods, a Statistical DownScaling Model (SDSM) and Multivariate Adaptive Constructed Analogs (MACA), were evaluated, with the SDSM providing superior performance for local climate conditions. To improve precipitation input accuracy, twenty ensemble scenarios were generated using the SDSM, and various machine learning algorithms were applied to identify the optimal ensemble. Among these, the Extreme Gradient Boosting (XGBoost) algorithm exhibited the lowest error and was selected for producing high-quality precipitation time series. This methodology is integrated into the MIDAS (Machine Learning-Based Integration of Downscaled Projections for Accurate Simulation) approach, which leverages machine learning to enhance climate input precision and reduce uncertainty in hydrological modeling. Water yield was simulated over the period 1961–2060, combining observed and projected climate data to capture both historical trends and future changes. The results show that combining statistical downscaling with machine learning algorithms can help improve the accuracy of water yield projections under climate change and be useful for water resource planning, forest management, and climate adaptation. Full article

► Show Figures

Figure 1

35 pages, 2094 KB

Open AccessReview

The Use of Biosorbents in Water Treatment

by Mothusi Molebatsi, Bonang Nkoane, Ngonye Keroletswe, Samuel Chigome and Moses Tlhabologo Kabomo

Environments 2025, 12(9), 302; https://doi.org/10.3390/environments12090302 - 29 Aug 2025

Viewed by 910

Abstract

Biosorbents are materials of biological origin (microbial, biomass-derived waste, or industrial by-products) used to adsorb or absorb pollutants. They have been used to remove various contaminants, including heavy metals, dyes, and pharmaceuticals. Their effectiveness is due to the different functional groups that interact [...] Read more.

Biosorbents are materials of biological origin (microbial, biomass-derived waste, or industrial by-products) used to adsorb or absorb pollutants. They have been used to remove various contaminants, including heavy metals, dyes, and pharmaceuticals. Their effectiveness is due to the different functional groups that interact with pollutants, including hydroxyl, amino, carboxyl, and phosphate groups. This review explores the various kinds of biosorbents (classification), mechanisms, and factors influencing biosorption, such as biomass content, time, temperature, pH, and concentration of pollutants, synthesis methods of biosorbents, and the current state of research on biosorbents. The review highlights the advantages of biosorbents, along with the challenges encountered, such as difficulty in regeneration and variability in performance. Finally, the review identifies research gaps and future directions, including exploration of modified/synthetic biosorbents for the removal of multi-component pollutants. Full article

► Show Figures

Graphical abstract

16 pages, 1635 KB

Open AccessArticle

Floral Characteristics Alter the Abundance and Richness of Bees Captured in Passive Traps

by Madison Mazur, Christine Bell, Michael E. Dillon and Lusha M. Tronstad

Environments 2025, 12(9), 301; https://doi.org/10.3390/environments12090301 - 28 Aug 2025

Viewed by 765

Abstract

Bees are vital pollinators that maintain plant populations by transporting pollen among individuals; however, bees are declining, and information on how habitat characteristics alter the catch of bees in traps is needed to better assess monitoring. Few studies have measured how catch in [...] Read more.

Bees are vital pollinators that maintain plant populations by transporting pollen among individuals; however, bees are declining, and information on how habitat characteristics alter the catch of bees in traps is needed to better assess monitoring. Few studies have measured how catch in passive traps may be altered by floral resources despite the well-known dependence of pollinators on forbs. We investigated the degree to which pollinating insects were attracted to vane traps and bee bowls placed at sites that varied in flower densities (0–800 flowers/m²). We also assessed if the catch of bees was better explained by flower characteristics directly around traps (subsite) or average flower characteristics at a site. Floral density, richness and surface area were measured in 1 m² quadrats at each subsite. The surface area of flowers explained more variance in bees captured compared to the density or richness of flowers. Traps placed in areas with lower flower surface area captured the more bees and a more diverse sample. Floral resources at the subsite and site explained a similar amount of variance in the number of bees captured, suggesting that pollinators respond to flowers at both scales. We provide a method of correcting pollinator abundance by flower surface area to make catch in passive traps more comparable among areas. We can select sites that minimize or maximize the catch of bees by understanding how floral resources change the effectiveness of passive traps. Full article

► Show Figures

Figure 1

25 pages, 4436 KB

Open AccessArticle

Selective Adsorption Performance of a High-Capacity Mesoporous Silica Aerogel for Fluoroquinolones

by Yifan Zhao, Lin Gu, Zhihan Liu, Junyu Zhang, Wei Xia, Peng Wang, Wenlei Zhai, Guangxin Yang, Xiaosheng Shen, Chengqi Fan and Cong Kong

Environments 2025, 12(9), 300; https://doi.org/10.3390/environments12090300 - 28 Aug 2025

Viewed by 502

Abstract

Fluoroquinolone antibiotics (FQs) are widely applied in veterinary practice and animal husbandry and frequently persist in organic waste liquids (OWLs), creating substantial environmental and health risks when untreated. A high-capacity mesoporous silica aerogel (SA-60) was produced via a cost-effective sol–gel route from water [...] Read more.

Fluoroquinolone antibiotics (FQs) are widely applied in veterinary practice and animal husbandry and frequently persist in organic waste liquids (OWLs), creating substantial environmental and health risks when untreated. A high-capacity mesoporous silica aerogel (SA-60) was produced via a cost-effective sol–gel route from water glass, followed by ambient pressure drying at 60 °C for 6 h. SA-60 exhibited pronounced selectivity, providing a maximum adsorption capacity of 630.18 mg·g⁻¹ for enrofloxacin (ENR) in acetonitrile. Adsorption efficiency was weakly dependent on pH. Mechanistic analysis indicated combined physical and chemical interactions, with intra-particle diffusion governing the overall rate. Thermodynamic evaluation showed a spontaneous and endothermic process for ENR adsorption. Organic solvent type and water content were major determinants of adsorption efficiency. Durable performance was observed, with capacity retention above 80% after five adsorption-desorption cycles. The mesoporous architecture (surface area 249.21 m²·g⁻¹; average pore diameter 10.81 nm) supported the high uptake. These results identify SA-60 as a sustainable adsorbent for removing hazardous FQs from OWLs, offering a simple, energy-efficient approach for the source-level control of antibiotic pollution and improved environmental management. Full article

(This article belongs to the Topic New Advances in Adsorptive and Extractive Methods for Pollutant Removal)

► Show Figures

Graphical abstract

23 pages, 818 KB

Open AccessArticle

Integrating Circularity Micro-Indicators into Automotive Product Development to Evaluate Environmental Trade-Offs and Guide Sustainable Design Decisions

by Maria J. Simão, Joana Matos and Ricardo Simoes

Environments 2025, 12(9), 299; https://doi.org/10.3390/environments12090299 - 28 Aug 2025

Viewed by 591

Abstract

This study explores the integration of circular design principles into automotive product development, focusing on the environmental implications of design decisions related to geometry, material selection, and assembly methods. A case study approach was used to iteratively redesign a plastic automotive component, incorporating [...] Read more.

This study explores the integration of circular design principles into automotive product development, focusing on the environmental implications of design decisions related to geometry, material selection, and assembly methods. A case study approach was used to iteratively redesign a plastic automotive component, incorporating structural reinforcements and glass fiber (GF) to enhance performance. While these changes improved mechanical properties, they negatively impacted recyclability due to increased material heterogeneity and irreversible assembly using ultrasonic welding. Circularity performance was evaluated using the Recycling Desirability Index (RDI), Material Circularity Indicator (MCI), and circular design guidelines (CDGs). Despite achieving 20% recycled content, recyclability remained limited. Alternative design strategies—such as eliminating GF, replacing welding with mechanical fasteners, and enabling take-back systems—led to significant improvements in circularity scores. Notably, MCI analysis indicated that energy recovery pathways offered better circularity outcomes than landfilling. The findings highlight the importance of early-stage material standardization and assembly planning to enhance end-of-life recovery. This study underscores the environmental trade-offs inherent in current automotive design practices and calls for stronger collaboration between engineers, designers, and sustainability experts to align product development with circular economy goals. Findings emphasize the need for systemic changes in product development processes and industrial mindsets, including overcoming resistance to design modifications and fostering cross-departmental collaboration, to effectively implement circular economy principles in the automotive sector. Full article

► Show Figures

Figure 1

2 pages, 131 KB

Open AccessEditorial

Assessment of Soil Organic Carbon in Different Ecosystems by Using Field, Lab, and Modeling Methods

by Sutie Xu, Jing Hu, Navreet Kaur Mahal and Virginia L. Jin

Environments 2025, 12(9), 298; https://doi.org/10.3390/environments12090298 - 28 Aug 2025

Viewed by 431

Abstract

As the largest terrestrial carbon (C) pool, soil organic C (SOC) and its evaluation are important for understanding soil functions in different ecosystems [...] Full article

(This article belongs to the Special Issue Soil Organic Carbon Assessment)

12 pages, 517 KB

Open AccessArticle

Humidity Impact on Air Quality in Straw- and Reed-Bale Houses

by Jane Raamets, Lembit Nei, Aime Ruus, Mari Ivask and Karin Muoni

Environments 2025, 12(9), 297; https://doi.org/10.3390/environments12090297 - 28 Aug 2025

Viewed by 547

Abstract

The suitability of reed- and straw-bale houses for the temperate climate zone was assessed. The influence of indoor climate indicators (relative humidity, internal humidity load of the borders, CO₂, temperature, mould index) and the microbial community was evaluated on air quality [...] Read more.

The suitability of reed- and straw-bale houses for the temperate climate zone was assessed. The influence of indoor climate indicators (relative humidity, internal humidity load of the borders, CO₂, temperature, mould index) and the microbial community was evaluated on air quality in the bedrooms. No similar studies on indoor air quality have been reported previously. The current study involved (1) indoor air quality indicators (relative humidity, CO₂, and temperature) in air and at two different heights in the walls were measured; (2) air quality was tested in the bedrooms of the studied houses, and the microbial species in air and walls were determined; (3) the impact of microbial communities on the air quality in the bedrooms of straw- and reed-bale buildings was assessed. Internal moisture was higher in the reed-bale buildings. The indoor air of the straw-bale and reed-bale buildings included more colonies than the outside air, but this did not affect indoor air quality. Full article

► Show Figures

Figure 1

13 pages, 5199 KB

Open AccessArticle

Cumulative Environmental Impacts of Wind Power Complex Construction in Mountain Forests: An Ecological Restoration Perspective Through Avian Diversity

by Chang-Eon Park and Hee-Cheon Park

Environments 2025, 12(9), 296; https://doi.org/10.3390/environments12090296 - 27 Aug 2025

Viewed by 486

Abstract

Countless studies have been conducted on cumulative environmental impacts, but not many have been performed on specific cases of the presence or absence of actual cumulative environmental impacts and restoration, and there is no standardized method for judging cumulative environmental impacts. With our [...] Read more.

Countless studies have been conducted on cumulative environmental impacts, but not many have been performed on specific cases of the presence or absence of actual cumulative environmental impacts and restoration, and there is no standardized method for judging cumulative environmental impacts. With our study, we aimed to fill this research gap. We methodologically propose that environmental impacts and restoration can be intuitively expressed by measuring alpha diversity, beta diversity, and gamma diversity in avian fauna. We hope that our proposal will enable many researchers to apply these measurements not only to wind power projects but also various others. This will let them move away from data-less claims and rather track changes in environmental impacts with objective data, considering cumulative environmental impacts and recovery of impacts over time. The results showed that there were changes in the three types of diversity due to the development of wind power complexes on mountain ridges during construction, and the environment was restored over several years. In conclusion, cumulative environmental impacts due to the development of wind power complexes on mountain ridges were not found when limited to avifauna, and impacts due to construction showed a pattern of restoration after construction. There were also cases where restoration occurred even during construction. Full article

(This article belongs to the Special Issue Environments: 10 Years of Science Together)

► Show Figures

Figure 1

34 pages, 897 KB

Open AccessArticle

AI-Driven Circular Waste Management Tool for Enhancing Circular Economy Practices in Healthcare Facilities

by Maria Assunta Cappelli, Eva Cappelli and Francesco Cappelli

Environments 2025, 12(9), 295; https://doi.org/10.3390/environments12090295 - 27 Aug 2025

Viewed by 855

Abstract

The increasing complexity in hospital waste management requires innovative solutions that integrate sustainability and regulatory compliance. This study proposes an AI-based decision tool to support the circular management of healthcare waste. The approach combines two key elements: (i) the systematic qualitative analysis of [...] Read more.

The increasing complexity in hospital waste management requires innovative solutions that integrate sustainability and regulatory compliance. This study proposes an AI-based decision tool to support the circular management of healthcare waste. The approach combines two key elements: (i) the systematic qualitative analysis of international, European, and national regulations, scientific literature, and best practices aimed at identifying strategic actions; (ii) the prioritization of these actions through machine learning, using a Random Forest classifier. We identified 55 actions, grouped into 13 thematic areas, and used them as input variables to assess their impact on regulatory compliance. The variable importance analysis allowed us to classify actions according to their strategic relevance, guiding the structure of the tool and its user interface. Validation, conducted on four simulated case studies, demonstrated the system’s ability to improve compliance monitoring, operational efficiency, and the implementation of circular economy and Zero-Waste strategies. The proposed model represents a scalable and evidence-based solution capable of supporting the ecological transition of healthcare facilities in line with EU directives and the Sustainable Development Goals. Full article

(This article belongs to the Special Issue Environments: 10 Years of Science Together)

► Show Figures

Figure 1

22 pages, 4496 KB

Open AccessReview

Challenges and Disadvantages of PVA-Based Media Application in Wastewater Treatment: A Mini-Review

by Tamás Kloknicer, Anita Szabó, Dániel Benjámin Sándor and Genoveva Filipcsei

Environments 2025, 12(9), 294; https://doi.org/10.3390/environments12090294 - 26 Aug 2025

Viewed by 581

Abstract

In this mini-review, we compiled various types of Polyvinyl-alcohol-based hydrogel construction recipes and methodologies, categorizing them based on their added materials or production methods for wastewater applications. This classification is vital for identifying recipes that require improvement in future research and for analyzing [...] Read more.

In this mini-review, we compiled various types of Polyvinyl-alcohol-based hydrogel construction recipes and methodologies, categorizing them based on their added materials or production methods for wastewater applications. This classification is vital for identifying recipes that require improvement in future research and for analyzing their practical parameters, such as durability, surface area, and cleaning efficiency. To evaluate their potential for long-term use, we examined the durability of these groups. D- and E-type media demonstrated notable durability, exhibiting lower degradation rates compared to A- and B-types. Additionally, we gathered information on the measuring technologies available for assessing the specific surface area of these media, a crucial parameter for both biological and adsorbent applications. Based on the available data, we recommend enhancing the quality and quantity of measurements by integrating and improving microscopic analysis and adsorption techniques. Furthermore, these hydrogels showed superior cleaning capacities compared to traditional carriers, with D- and E-types excelling in adsorption capabilities, while the C-type exhibited exceptional potential for biological treatment. Full article

(This article belongs to the Special Issue Editorial Board Members’ Collection Series: Wastewater Treatment)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Environments, Volume 12, Issue 9 (September 2025) – 33 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI