In this paper, we are consider processing of soils erosion and his way on protection expoitation of water for population water supply, melioration's systems for irrigation and for strew of manger of the Lim river with the tug and suspend bank (Montenegro, Yugoslavia). We are given suggestions for protective utilization of agricultural and forest lands and the possibilities of water exploitation from Bistrica river (Montenegro, Yugoslavia). That is useful for fishing, irrigation, energetic, tourism and water supply. In this paper, you can meet some suggestions about exploitations of minerals and organic fertilizars that are not toxics and they not any influence on pollution of land and water.

Expert system (ES) is a software which unites mathematical models, empirical knowledge, expert evaluation, engineering intuition, heuristic rules and necessary informations which through the inference engine gives useful advise to the decision maker, to reach a correct and timely decision. The objectives of ES cover a wide range of tasks of protection of waters, out of which the following seem to be the most important: diagnostics, monitoring, estimation, interpretation, planning and design of systems, maintenance, trouble shooting, education, management.

The derivation of sediment quality guideline values (SQGVs) presents significant challenges. Arguably the most important challenge is to conduct toxicity tests using contaminated sediments with physico-chemistry that represents real-world scenarios. We used a novel metal spiking method for an experiment that ultimately aims to derive a uranium SQGV. Two pilot studies were conducted to inform the final spiking design, i.e. percolating a uranyl sulfate solution through natural wetland sediments. An initial pilot study that used extended mixing equilibration phases produced hardened sediments not representative of natural sediments. A subsequent percolation method produced sediment with similar texture to natural sediment and was used as the method for spiking the sediments. The range of total recoverable uranium (TR-U) concentrations achieved was 8–3200 mg/kg. This reflected the concentrations found in natural wetlands and water management ponds found on a uranium mine site and was above natural levels. Dilute-acid extractable uranium (AE-U) concentrations were >80% of total concentrations, indicating that much of the uranium in the spiked sediment was labile and potentially bioavailable. The portion of TR-U extractable as AE-U was similar at the start and end of the 4.5-month field-deployment. Porewater uranium (PW–U) analyses indicated that partition coefficients (Kd) were 2000–20,000 L/kg, and PW-U was greater in post- than pre-field-deployed samples when TR-U was ≤1500 mg/kg, indicating the binding became weaker during the field-deployment period. At higher spiked-U concentrations, the PW-U was lower post-field-deployment. Comparing the physico-chemical data of the spiked sediments with environmental monitoring data from sediments in the vicinity of a uranium mining operation indicated that they were representative of sediments contaminated by mining and that the U-spiked sediments had a clear U concentration gradient. This confirmed the suitability of the spiking procedure for preparing sediments that were suitable for deriving a SQGV for uranium.

Free refill drinking water kiosks are an essential sustainable water supply system for people in metropolitan areas worldwide. Despite their importance in urban settings, the impact of microplastic contamination remains elusive. Here, we investigated the occurrence and characteristics of microplastics in drinking-water samples collected from 22 self-distributed refill kiosks located in 14 multiuse urban parks spread across nine municipalities in Mexico City (Mexico). The results showed that microplastics were detected in all the samples, with an overall mean concentration of 74.18 ± 48.76 microplastics L⁻¹. The abundance of microplastics was significantly different between sampled kiosks, ranging from 23 ± 11.31 to 202 ± 28.39 microplastics L⁻¹. There were more fibrous microplastics (88%) than fragments (9%) and films (3%), with the majority (56%) being <200 μm in length. They were predominantly transparent (85%), with only a few being colored (15%; blue, red, green, and brown). Attenuated Total Reflection-Fourier-transform infrared spectroscopy further revealed microplastics of various polymer types, including polyvinyl alcohol, high-density polyethylene, polypropylene, polyvinyl acetate, ethylene vinyl alcohol, acrylic, alkyd resin, and viscose. Based on our findings, drinking water from urban refill kiosks exposes children more than adults to microplastics. Furthermore, the steps that should be taken at urban refill kiosks to prevent microplastic pollution while offering recreational services to people have been highlighted. Therefore, this first study serves as a wake-up call to urban water management to improve the safety of water from emerging pollutants like microplastics in the infrastructure of refill kiosks.

Initial Cadmium (Cd) isotope fractionation studies in cereals ascribed the retention of Cd and its light isotopes to the binding of Cd to sulfur (S). To better understand the relation of Cd binding to S and Cd isotope fractionation in soils and plants, we combined isotope and XAS speciation analyses in soil-rice systems that were rich in Cd and S. The systems included distinct water management (flooded vs. non-flooded) and rice accessions with (excluder) and without (non-excluder) functional membrane transporter OsHMA3 that transports Cd into root vacuoles. Initially, 13% of Cd in the soil was bound to S. Through soil flooding, the proportion of Cd bound to S increased to 100%. Soil flooding enriched the rice plants towards heavy isotopes (δ¹¹⁴/¹¹⁰Cd = −0.37 to −0.39%) compared to the plants that grew on non-flooded soils (δ¹¹⁴/¹¹⁰Cd = −0.45 to −0.56%) suggesting that preferentially light Cd isotopes precipitated into Cd sulfides. Isotope compositions in CaCl₂ root extracts indicated that the root surface contributed to the isotope shift between soil and plant during soil flooding. In rice roots, Cd was fully bound to S in all treatments. The roots in the excluder rice strongly retained Cd and its lights isotopes while heavy isotopes were transported to the shoots (Δ¹¹⁴/¹¹⁰Cdₛₕₒₒₜ₋ᵣₒₒₜ 0.16–0.19‰). The non-excluder rice accumulated Cd in shoots and the apparent difference in isotope composition between roots and shoots was smaller than that of the excluder rice (Δ¹¹⁴/¹¹⁰Cdₛₕₒₒₜ₋ᵣₒₒₜ −0.02 to 0.08‰). We ascribe the retention of light Cd isotopes in the roots of the excluder rice to the membrane transport of Cd by OsHMA3 and/or chelating Cd–S complexes in the vacuole. Cd–S was the major binding form in flooded soils and rice roots and partly contributed to the immobilization of Cd and its light isotopes in soil-rice systems.

Biochar is often applied to paddy soils as a soil improver, as it retains nutrients and increases C sequestration; as such, it is a tool in the move towards C-neutral agriculture. Nitrogen (N) fertilizers have been excessively applied to rice paddies, particularly in small farms in China, because N is the major limiting factor for rice production. In paddy soils, dynamic changes in iron (Fe) continuously affect soil emissions of methane (CH₄) and carbon dioxide (CO₂); however, the links between Fe dynamics and greenhouse gas emissions, dissolved organic carbon (DOC), and rice yields following application of biochar remain unclear. The aims of this study were to examine the effects of two rates of nitrogen (N)-enriched biochar (4 and 8 t ha⁻¹ y⁻¹) on paddy soil C emissions and storage, rice yields, and Fe dynamics in subtropical early and late rice growing seasons. Field application of N-enriched biochar at 4 and 8 t ha⁻¹ increased C emissions in early and late rice, whereas application at 4 t ha⁻¹ significantly increased rice yields. The results of a culture experiment and a field experiment showed that the application of N-enriched biochar increased soil Fe²⁺concentration. There were positive correlations between Fe²⁺concentrations and soil CO₂, CH₄, and total C emissions, and with soil DOC concentrations. On the other way around, these correlations were negative for soil Fe³⁺concentrations. In the soil culture experiment, under the exclusion of plant growth, N-enriched biochar reduced cumulative soil emissions of CH₄ and CO₂. We conclude that moderate inputs of N-rich biochar (4 t ha⁻¹) increase rice crop yield and biomass, and soil DOC concentrations, while moderating soil cumulative C emissions, in part, by the impacts of biochar on soil Fe dynamics. We suggest that water management strategies, such as dry-wet cycles, should be employed in rice cultivation to increase Fe²⁺ oxidation for the inhibition of soil CH₄ and CO₂ production. Overall, we showed that application of 4 t ha⁻¹ of N-enriched biochar may represent a potential tool to improve sustainable food production and security, while minimizing negative environmental impacts.

Water management such as drainage for creating aerobic conditions is considered to be an adequate method for reducing the accumulation of arsenic (As) in rice grains; however, it is difficult to conduct drainage operations in some areas that experience a lengthy rainy season as well as in soils with poor drainage. In this regard, application of oxygen-releasing compounds (ORCs) may be an alternative method for maintaining aerobic conditions even under flooding in paddy soils. Therefore, a pot experiment was conducted to investigate the effects of application of an ORC, calcium peroxide (CaO₂), on the growth and accumulation of As in rice plants grown in As-contaminated paddy soils. The rice plants were grown in two soils with different characteristics and As levels, and all of the tested soils were treated with 0, 5, 10, and 20 g CaO₂ kg⁻¹. Results revealed that the concentration of As and the distribution of arsenite in the pore water of all tested soils was reduced by CaO₂ application. In addition, the grain yields increased and the concentration of inorganic As in brown rice decreased by 25–45% upon CaO₂ treatment of low-As-level soils (<16 mg kg⁻¹). However, the effect of CaO₂ application on the accumulation of inorganic As in brown rice in As-enriched soils (>78 mg kg⁻¹) could not found in this study, due to the rice plant suffered from serious As phytotoxicity. It suggests that CaO₂ amendment may be suitable for reducing the As concentration of rice grains grown in low-As-level paddy soils, but for As-enriched soils, the proposed CaO₂ application method is not feasible.

Antibiotics, such as sulfonamides (SAs), have recently raised concern as wastewater treatment plants (WWTPs) partly remove them, and thus, SAs continuously enter the aquifers. In this context, the aims of this work are to (1) investigate the temporal evolution of SAs and metabolites in an urban aquifer recharged by a polluted river; (2) identify the potential geochemical processes that might affect SAs in the river-groundwater interface and (3) evaluate the ecological and human health risk assessment of SAs. To this end, 14 SAs and 4 metabolites were analyzed in river and urban groundwater from the metropolitan area of Barcelona (NE, Spain) in three different sampling campaigns. These substances had a distinct behavior when river water, which is the main recharge source, infiltrates the aquifer. Mixing of the river water recharge into the aquifer drives several redox reactions such as aerobic respiration and denitrification. This reducing character of the aquifer seemed to favor the natural attenuation of some SAs as sulfamethoxazole, sulfapyridine, and sulfamethizole. However, most of the SAs detected were not likely to undergo degradation and adsorption because their concentrations were constant along groundwater flow path. In fact, the intensity of SAs adsorption is low as the retardation factors are close to 1 at average groundwater pH of 7.2 for most SAs.Finally, risk quotients (RQs) are used to evaluate the ecological and human health risks posed by single and mixture of SAs in river water and groundwater, respectively. Life-stage RQs of the SAs detected in groundwater for the 8 age intervals were low, indicating that SAs and their mixture do not pose any risk to human beings. Concerning the environmental risk assessment, SAs do not pose any risk for algae, fish and crustaceans as the RQs evaluated are further lower than 0.1.

The bioavailability of the metalloid arsenic (As) in paddy soil is controlled by microbial cycling of As and other elements such as iron (Fe) and sulfur (S), which are strongly influenced by water management in paddy fields. In this study, we evaluated how water management affects As bioavailability by growing rice plants in a geogenic As-contaminated soil. We determined As speciation in soil porewater and the diversity of the associated microbial community. Continuous flooding enhanced the release of Fe and As and increased arsenite (As(III)) and methylated As species concentrations in the rice grain compared with aerobic treatment. Total inorganic and organic As in the grain was 84% and 81% lower, respectively, in the aerobic treatment compared with the continuous flooding treatment. The amounts of Fe(III)-reducing bacteria (FeRB) increased in the flooded rhizosphere soil. The abundance of FeRB in the soil correlated with the dissolution of Fe and As. Among the As-transformation genes quantified, the aioA gene for As(III) oxidation and arsM gene for As(III) methylation were most abundant. The arsM copy number correlated positively with the levels of dsrB (dissimilatory (bi) sulfite reductase β-subunit), suggesting that dissimilatory sulfate-reducing bacteria (SRB) may play an important role in dimethylarsenate (DMAs(V)) production in soil. Our results show that decreased populations of rhizosphere FeRB and SRB contributed to a lower bioavailability of As, and decreased production of methylated arsenicals under oxic conditions.

Environmental observations of antibiotics and other pharmaceuticals have received attention as indicators of an urbanizing global water cycle. When connections between environment and development of antibiotic resistance (ABR) are considered, it is increasingly important to understand the life cycle of antibiotics. Here we examined the global occurrence of erythromycin (ERY) in: 1. wastewater effluent, inland waters, drinking water, groundwater, and estuarine and coastal systems; 2. sewage sludge, biosolids and sediments; and 3. tissues of aquatic organisms. We then performed probabilistic environmental hazard assessments to identify probabilities of exceeding the predicted no-effect concentration (PNEC) of 1.0 μg L−1 for promoting ABR, based on previous modeling of minimum inhibitory concentrations and minimal selective concentrations of ERY, and measured levels from different geographic regions. Marked differences were observed among geographic regions and matrices. For example, more information was available for water matrices (312 publications) than solids (97 publications). ERY has primarily been studied in Asia, North America and Europe with the majority of studies performed in China, USA, Spain and the United Kingdom. In surface waters 72.4% of the Asian studies have been performed in China, while 85.4% of the observations from North America were from the USA; Spain represented 41.9% of the European surface water studies. Remarkably, results from PEHAs indicated that the likelihood of exceeding the ERY PNEC for ABR in effluents was markedly high in Asia (33.3%) followed by Europe (20%) and North America (17.8%). Unfortunately, ERY occurrence data is comparatively limited in coastal and marine systems across large geographic regions including Southwest Asia, Eastern Europe, Africa, and Central and South America. Future studies are needed to understand risks of ERY and other antibiotics to human health and the environment, particularly in developing regions where waste management systems and treatment infrastructure are being implemented slower than access to and consumption of pharmaceuticals is occurring.