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The Mar Menor is a hypersaline coastal lagoon with salinity values ranging from 41.9 to 45.5. The system is subjected to a high anthropic pressure that causes an intense eutrophication process, followed by a recovery of the macrophyte meadows. This study focuses on the distribution of the main greenhouse gases (CO2, CH4 and N2O) and was carried out in the extreme seasonal conditions of winter and summer during the year 2018. Ademetionine chemical Sediment-water-atmosphere exchanges and biochemical processes in the water column appeared to be the main factors to explain the variability of these gases. Dissolved Inorganic Carbon (DIC), CH4 and N2O benthic fluxes values obtained in this study, were of 91 ± 29 mmol m-2 d-1, 3.9 ± 1.9 μmol m-2 d-1 and -0.65 μmol m-2 d-1, respectively, along with an important seasonal variation observed, with an increase of DIC and CH4 benthic fluxes during the summer season. Mean values of partial pressure of CO2 (pCO2) in surface water were of 579 μatm in winter and 464 μatm in summer, therefore we can establish that the Mar Menor acts as a source of this gas emitting 3.3 ± 3.0 mmol CO2 m-2 d-1 to the atmosphere. In spite of this, the Mar Menor has a strong autotrophic behaviour partly due to the recovery of the macrophyte meadows, presenting an estimated NEP of 101 mmol m-2 d-1. Regarding to CH4, the mean fluxes to the atmosphere were of 8.0 ± 5.8 μmol m-2 d-1 and there was evidence of CH4 production in the water column that increased in summer. Last of all, in the case of N2O the system acts as a sink with values of -0.65 ± 0.5 μmol m-2 d-1, presenting an intake of N2O that is usually detected in pristine systems.Maintaining and improving surface water quality requires knowledge of nutrient and sediment loads due to past and future land-use practices, but historical data on land cover and its changes are often lacking. In this study, we tested whether land-use-specific export coefficients can be used together with satellite images (Landsat) and/or regional land-use statistics to estimate riverine nutrient loads and concentrations of total nitrogen (TN), total phosphorus (TP), and suspended solids (SS). The study area, Simojoki (3160 km2) in northern Finland, has been intensively drained for peatland forestry since the 1960s. We used different approaches at multiple sub-catchment scales to simulate TN, TP, and SS export in the Simojoki catchment. The uncertainty in estimates based on specific export coefficients was quantified based on historical land-use changes (derived from Landsat data), and an uncertainty boundary was established for each land-use. The uncertainty boundary captured at least 60% of measured values of TN, TP, and SS loads or concentrations. However, the uncertainty in estimates compared with measured values ranged from 7% to 20% for TN, 0% to 18% for TP, and 13% to 43% for SS for different catchments. Some discrepancy between predicted and measured loads and concentrations was expected, as the method did not account for inter-annual variability in hydrological conditions or river processes. However, combining historical land-use change estimates with simple export coefficients can be a practical approach for evaluating the influence on water quality of historical land-use changes such as peatland drainage for forest establishment.In order to explore the impact of antibiotics on the bacterial metabolic cycling of nitrate within contaminated soil and groundwater environments, we compared the effects of polymyxin B (PMB) and ciprofloxacin (CIP) concentration gradients on the distribution and activity of a wild type (WT) and a flagella deficient mutant (Δflag) of Shewanella oneidensis MR-1 in a microfluidic gradient chamber (MGC). link2 Complementary batch experiments were performed to measure bacteriostatic versus bactericidal concentrations of the two antibiotics, as well as their effect on nitrate reduction. Prior work demonstrated that PMB disrupts cell membranes while CIP inhibits DNA synthesis. Consistent with these modes of action, batch results from this work show that PMB is bactericidal at lower concentrations than CIP relative to their respective minimum inhibitory concentrations (MICs) (≥5× MICPMB vs. ≥20× MICCIP). Concentration gradients from 0 to 50× the MIC of both antibiotics were established in the MGC across a 2-cm interconnected pore network, with nutrients injected at both concentration boundaries. The WT cells could only access and reduce nitrate in regions of the MGC with PMB at less then 18× MICPMB, whereas this occurred with CIP up to 50× MICCIP; and cells extracted from these MGCs showed no antibiotic resistance. The distribution of Δflag cells was further limited to lower antibiotic concentrations (≤1× MICPMB, ≤43× MICCIP) due to inability of movement. These results indicate that S. oneidensis access and reduce nitrate in bactericidal regions via chemotactic migration without development of antibiotic resistance, and that this migration is inhibited by acutely lethal bactericidal levels of antibiotics.Releases of natural gas into groundwater from oil and gas exploration, production, or storage (i.e., “stray gas”) can pose a risk to groundwater users and landowners in the form of a fire or explosive hazard. The acute nature of stray gas risk differs from the long-term health risks posed by the ingestion or inhalation of other petroleum hydrocarbons (e.g., benzene). Stray gas also exhibits different fate and transport behaviors in the environment from other hydrocarbon contaminants, including the potential for rapid and extensive transport of free-phase gas through preferential pathways, and the resulting variable and discontinuous spatial distribution of free and dissolved gas phases. While there is extensive guidance on response actions for releases of other hydrocarbons such as benzene, there are relatively few examples available in the technical literature that discuss appropriate response measures for the investigation and remediation of stray gas impacts. This paper describes key considerations in the physical, chemical, and hydrogeological characteristics of stray gas releases and implications for the improved investigation and mitigation of associated risks.Modern lifestyle demands high-end commodities, for instance, cosmetics, detergents, shampoos, household cleaning, sanitary items, medicines, and so forth. In recent years, these products’ consumption has increased considerably, being antibiotics and some other pharmaceutical and personal care products (PPCPs). Several antibiotics and PPCPs represent a wide range of emerging contaminants with a straight ingress into aquatic systems, given their high persistence in seawater, effluent treatment plants, and even drinking water. Under these considerations, the necessity of developing new and affordable technologies for the treatment and sustainable mitigation of pollutants is highly requisite for a safer and cleaner environment. One possible mitigation solution is an effective deployment of nanotechnological cues as promising matrices that can contribute by attending issues and improving the current strategies to detect, prevent, and mitigate hazardous pollutants in water. Focused on nanoparticles’ distinctive physical and chemical properties, such as high surface area, small size, and shape, metallic nanoparticles (MNPs) have been investigated for water remediation. MNPs gained increasing interest among research groups due to their superior efficiency, stability, and high catalyst activity compared with conventional systems. This review summarizes the occurrence of antibiotics and PPCPs and the application of MNPs as pollutant mitigators in the aquatic environment. The work also focuses on transportation fate, toxicity, and current regulations for environmental safety.We proposed a novel approach based on dual ammonium and nitrate nitrogen isotope ratios (δ15NNH4 and δ15NNO3, respectively) axes to identify nitrogen sources in intensive livestock farming watersheds, especially those with swine excreta treatment facilities. The δ15NNH4 and δ15NNO3 values in water samples were measured monthly in 2016-2017. Soil and mineral fertilizers, sewage, sewage effluent, manure, and swine effluents were the five sources considered to identify nitrogen sources. The results showed that nitrogen pollution from agricultural activities was well reflected by the seasonal δ15NNH4 and δ15NNO3 patterns in the river, and microbial nitrification was suggested as the dominant nitrogen transformation process in the river. This study revealed that δ15NNH4 and δ15NNO3 axes provided better results than the traditionally used nitrate oxygen (δ18ONO3) and δ15NNO3 axes for identifying nitrogen sources in agricultural watersheds with swine excreta treatment facilities. The mixing model results showed that stream water was severely contaminated with swine effluents (e.g., a mean minimum contribution of 31%), thus affecting the quality of the mainstream (p = 0.068 less then 0.10). This study was the first successful application of dual δ15NNH4 and δ15NNO3 axes to better understand nitrogen sources in intensive livestock farming watersheds with swine excreta treatment facilities.Microplastics may affect the physiology, behaviour and populations of aquatic and terrestrial fauna through many mechanisms, such as direct consumption and sensory disruption. However, the majority of experimental studies have employed questionably high dosages of microplastics that have little environmental relevance. Predation, in particular, is a key trophic interaction that structures populations and communities and influences ecosystem functioning, but rarely features in microplastic research. Here, we quantify the effects of low (~65-114 MP/L) and high (~650-1140 MP/L) microplastic concentrations on the feeding behaviour of a ubiquitous and globally representative key marine predator, the shore crab, Carcinus maenas. link3 We used a functional response approach (predator consumption across prey densities) to determine crab consumption rates towards a key marine community prey species, the blue mussel Mytilus edulis, under low and high microplastic concentrations with acute (8h) and chronic (120h) microplastic exposure times. For both the acute and chronic microplastic exposure experiments, proportional prey consumption by crabs did not differ with respect to microplastic concentration, but significantly decreased over increasing prey densities. The crabs thus displayed classical, hyperbolic Type II functional responses in all experimental groups, characterised by high consumption rates at low prey densities. Crab attack rates, handling times and maximum feeding rates (i.e. functional response curves) were not significantly altered under lower or higher microplastics concentrations, or by acute or chronic microplastic exposures. Here, we show that functional response analyses could be widely employed to ascertain microplastic impacts on consumer-resource interactions. Furthermore, we suggest that future studies should adopt both acute and chronic microplastic exposure regimes, using environmentally-relevant microplastic dosages and types as well as elevated future scenarios of microplastic concentrations.