Research Journal of Ecology and Environmental Sciences

Water management is a critical challenge for uranium processing operations in arid regions, where industrial activities depend heavily on limited groundwater resources. This study evaluates the performance of the filter cloth washing water recycling circuit at the Aïr Mining compagny (SOMAÏR) uranium processing plant in Niger and identifies the principal factors limiting continuous water reuse. The investigation combined operational water-flow... Water management is a critical challenge for uranium processing operations in arid regions, where industrial activities depend heavily on limited groundwater resources. This study evaluates the performance of the filter cloth washing water recycling circuit at the Aïr Mining compagny (SOMAÏR) uranium processing plant in Niger and identifies the principal factors limiting continuous water reuse. The investigation combined operational water-flow monitoring, historical production records, field sampling from Pit 3, physicochemical characterization of recycled water, suspended-solids determination, and particle-size analysis. Under normal operating conditions, the recycling circuit achieved an average recycling efficiency of 57.5%, corresponding to approximately 850 m³/day of industrial water savings. The recycled water exhibited a density of 0.994 g/cm³, pH of 2.53, oxidation- reduction potential of 480 mV, and suspended-solids concentration of 2052 mg/L. Particle-size analysis showed that approximately 97.6% of the suspended particles were smaller than 200 μm, allowing a substantial fraction of solids to bypass the 250 μm vibrating-drainer screen and accumulate in Decanter 1. Progressive sediment accumulation, together with screen deterioration and mechanical limitations, reduced clarification capacity and ultimately interrupted the recycling circuit. Engineering measures including improved fine-particle separation, optimization of screen aperture, systematic screen maintenance, improved sludge removal, and continuous monitoring are therefore proposed. These measures could enhance recycling reliability, reduce freshwater consumption, and improve water- management sustainability at SOMAÏR. Read more

Opuntia ficus-indica (L.) Mill., commonly known as prickly pear, is a versatile plant widely used for food, medicinal, and cosmetic purposes in various regions of the Mediterranean and North Africa. This study provides a comparative ethnobotanical review of prickly pear uses in Algeria, Morocco, Tunisia, and Italy. In total, 74 articles were selected from ethnobotanical uses in Italy, Algeria, Morocco... Opuntia ficus-indica (L.) Mill., commonly known as prickly pear, is a versatile plant widely used for food, medicinal, and cosmetic purposes in various regions of the Mediterranean and North Africa. This study provides a comparative ethnobotanical review of prickly pear uses in Algeria, Morocco, Tunisia, and Italy. In total, 74 articles were selected from ethnobotanical uses in Italy, Algeria, Morocco and Tunisia. In the Maghreb, the plant is used for fruit production and processed products, such as jams, oils, and flours, as well as for traditional medicinal purposes. In Algeria and Morocco, the fruits and cladodes are used to treat digestive disorders, diabetes, and skin diseases. In Tunisia, products derived from O. ficus-indica are also applied in the cosmetic industry and for erosion control. In Italy, particularly in Sicily and Calabria, the prickly pear is a vital resource, used for both food consumption and for medicinal purposes. The cladodes, rich in mucilage, are applied as topical remedies for skin problems, while the fruits are a key ingredient in the preparation of traditional desserts. Furthermore, O. ficus-indica has historically been used as forage and to produce natural dyes. Results indicate that the versatility of this species, combined with its ability to adapt to extreme climates, makes it a valuable resource for the development of new nutraceutical and cosmetic products. However, further scientific research is necessary to explore the bio-functional potential of this plant and to promote its broader and more sustainable use, especially in arid and semi-arid regions. Read more

Silver nanoparticles (Ag+NPs) contamination in the environment is a serious concern. This study investigated selected heavy metal (Ag+, Cd2+, Cr2+ and Pb2+) concentrations at different sampling points to assess the risk to human health (infants, children, and adults). To do this, an enclosed area (laboratory) of 12.6 m X 8.5 m (107.1 m2) was clearly marked at different coded distances... Silver nanoparticles (Ag⁺NPs) contamination in the environment is a serious concern. This study investigated selected heavy metal (Ag⁺, Cd^2+, Cr²⁺ and Pb²⁺) concentrations at different sampling points to assess the risk to human health (infants, children, and adults). To do this, an enclosed area (laboratory) of 12.6 m X 8.5 m (107.1 m²) was clearly marked at different coded distances of S1, S2, S3, and S4 representing 2, 4, 6, and 8 m, while unpolluted atmosphere at 50 m away without Ag⁺NPs served as the control (S5). The silver fireworks were allowed to burn for an approximate 00h03m30s at each sampling points using a high-volume air sampler mounted at the Environmental Engineering Departmental Laboratory, Rivers State University, with windows and doors closed to simulate indoor conditions. Samples were digested using a mixture of analytical-grade nitric acid, analytical-grade hydrochloric acid and analyzed to evaluate the levels of heavy metals by atomic absorption spectrophotometry. The Ag⁺ result at S1 shows 30,000 µg/cm³, S2 was 29,000 µg/cm³, while S3 was 28000 µg/cm³ and then S4 was 13,000 µg/cm³. These results exceeded the permissible values of the United States National Ambient Air Concentration for rural, urban and industrial areas (0.0005, 0.004 and 0.6 µg/cm³, respectively). The result for the control (S5) (0.037 µg/cm³) was within the maximum allowable value. Results from other heavy metals such as Cd were 1000, 743, 401, 153, 0.001 µg/cm³, Cr was 5000, 4000, 3729, 2960, 0.002 µg/cm³, Pb was 0.048, 0.041, 0.035, 0.034 and 0.01, µg/cm³, respectively. However, higher values of Ag⁺, Cd, and Cr indicated a higher propensity for the metals to be toxic (bioavailable). In addition, the assessment of the potential health risk posed by these metals proved contaminated and harmful. Visitors recorded high values in exposure concentration (EC) and low values in average daily dose (ADD). Read more

Recent field investigations, performed across some of the less floristically known sectors of Calabria, have led to the discovery of Salsola tragus and Thymelaea gussonei, two new species for the regional vascular flora. By providing crucial biogeographical and taxonomic remarks, this work aims to contribute to the improvement of the knowledge of the rich, diversified and still poorly known native... Recent field investigations, performed across some of the less floristically known sectors of Calabria, have led to the discovery of Salsola tragus and Thymelaea gussonei, two new species for the regional vascular flora. By providing crucial biogeographical and taxonomic remarks, this work aims to contribute to the improvement of the knowledge of the rich, diversified and still poorly known native flora of Calabria. The biogeographical value of these new findings underlines the decisive role of field survey in the enhancement of the information on regional biodiversity, the essential basis for every further ecological study and conservation effort. Read more

Costus afer, a known medicinal plant used in the removal of total monocyclic aromatic hydrocarbon (TMAH) in crude oil-contaminated soil add to the list of plant that has the potential to restore the soil quality. This study investigated the potential of Costus afer plant at various ages (7, 14, 21, 28, 35, and 42 days old) to biodegrade crude oil-contaminated... Costus afer, a known medicinal plant used in the removal of total monocyclic aromatic hydrocarbon (TMAH) in crude oil-contaminated soil add to the list of plant that has the potential to restore the soil quality. This study investigated the potential of Costus afer plant at various ages (7, 14, 21, 28, 35, and 42 days old) to biodegrade crude oil-contaminated soil. The group-balanced block design (GBBD) was used in establishing the experiment. TMAH was quantified by the standard method, according to USEPA method using gas chromatography-mass spectrometry (GC-MS). The contamination of 48kg of sandy loam soil was simulated by mixing 0.5, 1.0, and 1.5L of Bonny-Light crude oil with the soil in three separate vessels to achieve conditions of low (C₁), medium(C₂), and high(C₃) contamination, respectively. An additional vessel with medium-level contaminated soil but no treatment (C₄) served as the control. The Costus afer plants were nursed and transplanted at the stated ages to each vessel except the control. Controlled irrigation was applied, and the setups were housed to shield them from rainfall. After 90 days of treatment, results showed that the 7 days old Costus afer plants produced the highest amount of TMAH reduction of 96.5, 39.8, and 32.1%, for C₁, C₂ and C₃, respectively, while the control (C₄) was 9.45%. Furthermore, the sequence of TMAH reduction by the plants was 7 days old, 14 days old, 21 days old, 28 days old, 35 days old, and 42 days old. Thus, in addition to its medicinal value, Costus afer plant also has the potential to biodegrade TMAH in crude oil-contaminated sandy loam soil. Read more

The teaching-learning relationship of natural medicine is key to avoid health problems in the population; adulterations and falsifications of frequently used plants are evident. The aim of this study is to raise public awareness and to urge institutions to incorporate contents in the student's curriculum. The curricula of different educational levels are analyzed to check the level of knowledge on... The teaching-learning relationship of natural medicine is key to avoid health problems in the population; adulterations and falsifications of frequently used plants are evident. The aim of this study is to raise public awareness and to urge institutions to incorporate contents in the student's curriculum. The curricula of different educational levels are analyzed to check the level of knowledge on the use of medicinal plants, as well as some regulations on quality controls. Of the wide range of species that are consumed by the population, some are detected in which adulterations and falsifications occur, although there is no danger in some cases, such as chamomiles, if a falsification occurs when consuming the whole plant instead of the flowering tops, which is where the properties reside. In other cases, adulteration occurs, generally unintentional, but very dangerous to health, such as horsetail. For a more effective quality control, we need public awareness and highly specialized personnel, with the capacity to inspect crops, markets and companies. Read more