Due to the progressive climate change on our planet, scientists are interested in solving this issue since it threatens not only certain regions or countries but also the world’s ecosystems and economies. Therefore, minimizing carbon dioxide (CO₂) emissions and reducing atmospheric levels are global priorities. Thus, it is necessary at this moment to develop an appropriate approach to reduce or stabilize CO₂ levels in the atmosphere. However, CO₂ capture projects are long-term, low-profitable, and high-risk environmental projects. Consequently, it is necessary to find an appropriate and sustainable CO₂ capture approach that is efficient in reducing atmospheric CO₂ levels while having a safe impact on the environment. Although carbon (C) is the key basic component used to produce biological compounds by photosynthetic organisms in terrestrial plants, the C pathway is a key factor affecting the capture of CO₂ by photosynthetic organisms. Among photosynthetic organisms, Paulownia, a multipurpose tree, is popular around the world for its timber and its potential role in CO₂ sequestration. Paulownia spp. belongs to the Paulowniaceae family and comprises a group of trees. These trees are primarily found in southeastern Asia, particularly in China, and have been intentionally grown for more than two millennia due to their ornamental, cultural, and medicinal value. The number of Paulownia species varies depending on taxonomic classification, ranging from 6 to 17. Among them, Paulownia tomentosa, Paulownia elongata, Paulownia fortunei, and Paulownia catalpifolia are the most widely recognized and favored species. The present review provides a comprehensive technical-economic scenario for the capture of one million tons of CO₂ by Paulownia trees (as a terrestrial plant model, grown on 2,400 ha⁻¹). P. tomentosa can be utilized in agroforestry systems to mitigate greenhouse gas (GHG) emissions within urban cities and emphasize the carbon storage potential of agroforestry. In conclusion, Paulownia trees as an environmental mass project showed great encouragement to investors and governments to expand these types of projects to achieve global climate goals by 2050.

The current work presents a novel and sustainable approach that uses the synthesized Chitosan/Ferrous Oxide Nanocomposite (CFON) to remove the organic azo dye, Acid Red 73 (AR73), a hazardous pollutant commonly found in industrial wastewater, from aqueous solutions and aquaculture effluents wastewater. The CFON exhibited excellent photocatalytic degradation performance under sunlight irradiation. Batch adsorption experiments were conducted to investigate the influence of various parameters on the removal efficiency of the dye, including pH, contact time, adsorbent dosage, initial concentration, and temperature. The results showed that the nanocomposite effectively achieved a maximum removal percentage of 99.3% under optimal conditions (pH 5 for 180 min at 80 and 100 mg with 75 mg L^-1 and 30 °C). Kinetic studies revealed that the adsorption process followed a pseudo-second-order model, indicating that chemisorption is the dominant mechanism. The impact of different light sources on dye removal efficiency was evaluated, confirming the superior performance of sunlight-driven photocatalysis. The application of CFON to improve water quality in aquaculture was investigated and showed effectively reduced conductivity, total dissolved solids, turbidity, and nitrate levels, demonstrating its potential for sustainable water management. This work highlights the promising potential of CFON as an environmentally friendly and efficient material to remove AR73 and improve aquaculture wastewater quality.

Several studies have shown the importance of using seaweed liquid extract (True-Algae-Max, TAM) as a fish feed additive, and fish-water conditioner. In addition, TAM has demonstrated significant growth improvement when used as a plant growth biostimulant. This study investigates whether seaweed liquid extract (TAM) can achieve good results in new experimental fields such as chromium remediation, plant germination, and live feed supplementation for marine invertebrate Copepod (Oithona nana). In this study, several doses of TAM were tested, for the first time, for their impact on the remediation of chromium (Cr⁶⁺) ions from aqueous solutions and as an aqua feed additive for marine copepods (Oithona nana). In addition, it has been tested as promising for the seed germination of Fenugreek (Trigonella foenum-graecum) and Faba bean (Vicia faba L.). The most important factors influencing the removal (%) of Cr⁶⁺, identified using a two-level Plackett–Burman factorial design, were selected for additional optimization utilizing a rotatable central composite design. The maximum adsorption of Cr⁶⁺ was 93.65% under ideal operating circumstances, which included an initial Cr⁶⁺ concentration of 60 mg L⁻¹, a temperature of 25 °C, a pH of 3, a TAM biomass of 0.05 g, and a contact time of 60 min at agitation conditions. Plackett–Burman design data shows the significance of each factor and how well the model fits the Cr⁶⁺ removal. The results of the germination experiment revealed that the highest significant increase in seed germination was achieved using a TAM level of 0.30 mg mL⁻¹ with V. faba (88%) and 0.03 mg mL⁻¹ with T. foenum-graecum (96.6%). Additionally, compared to the control group, TAM at a level of 0.037 mg mL⁻¹ showed high root length enhancement on V. faba (184%) and T. foenum-graecum (188%). The results of the copepod O. nana feeding additive experiment found that the group fed on starch supplemented with TAM at a level of 0.3 mL L⁻¹, compared to the control group that fed starch only, showed the highest increment in population growth (134.74%), fecundity (270.16%), and population composition of males (133.45%), adults (120.37%), and nauplius (203.18%). Moreover, compared to the control group, the copepod that fed starch supplemented with TAM levels achieved the highest Omega-9 content. In conclusion, it is shown that TAM is a feasible, efficient, and sustainable solution for biodegradable adsorbent for the Cr⁶⁺ from aqueous solution, enhances plant seed germination and root length, and is a novel feed additive for marine copepod O. nana, especially in marine invertebrate hatcheries.

The industry’s unregulated discharge of unprocessed trash is a major contributor to environmental contamination. Drinking water contaminated by heavy metals is a serious environmental and public health problem. Cadmium (Cd (II)) is one heavy metal frequently found in wastewater. Adsorption is the most widely used method for treating water contaminated with heavy metals due to its great performance, affordability, and ease of use. This work examined the potential for heavy metal adsorption in palm fronds, a chemically treated agricultural waste, using H₃PO₄-derived activated Carbon (also known as chemically treated Carbon from palm fronds, or CTCPFs) for Cd(II) adsorption. Extensive batch tests investigated the effects of pH, initial metal concentration, dosage of CTCPFs, and contract duration on adsorption at room Temperature (25 ± 1 °C). Using BET techniques, the surface area and porosity of the sample were measured, and the surface morphology was examined using SEM. FT-IR and XRD measurements were made. After 90 min, 99.65% of the Cd (II) had been removed. Cd (II) was efficiently adsorbed by CTCPFs (> 99%) at pH = 5,C₀ = 50 mg/l, CTCPFs dosage 1 g /250 ml at 45 ℃ and contact time 90 min. According to the findings, CTCPFs are a cost-effective, efficient, and environmentally friendly adsorbent that can treat heavy metal-contaminated industrial wastewater as impure water. They also show promise in removing Cd (II) under neutral conditions.