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Abstract A key question to be asked when developing regional water quality criteria with scarce toxicity data is whether such data need to be locally derived. To address this, ammonia toxicity data from local aquatic species in the Liao River were compared against data from species native and non-native to China, based on comparisons of the overall trends of species sensitivity distributions and derived water quality criteria. Liao River data were acquired by acute and chronic tests using five local freshwater invertebrate species, and then compiled alongside published data from Chinese national guidelines and international literature. Models of best fit using three species sensitivity distribution approaches (log-logistic, log-normal, and Burr III) did not vary markedly (r 2 >0.9), and no specific model provided a best fit across all data sets. The comparisons of the overall trend of species sensitivity distribution curves showed no significant differences at either a national (Chinese native taxa tested in China versus non-native taxa) or regional level (Liao River taxa versus non-Liao River taxa). The comparisons also revealed that the inclusion or exclusions of different ecological groups had little influence on the overall trends of species sensitivity distributions. These findings suggested data on non-local and non-native species, and data from local species tested elsewhere, could be appropriate for guiding the derivation of ammonia water quality criteria for regions such as Liao River. However, caution is needed when using hazardous concentration 5% values in the development of site-specific water quality criteria for a river basin due to the considerable variation observed for ammonia (16.8–56.6 mg/L), although these differences were not statistically significant. Based on the toxicity test evaluation, a preliminary acute value of 10.0 mg/L and chronic value of 1.7 mg/L (at pH of 7.0 and 20 °C) are proposed as site-specific ammonia water quality criteria for the Liao River, China. Graphical abstract fx1 Highlights • Liao River represents a model cool temperate freshwater system in China. • Acute and chronic ammonia toxicity was detected in 5 Liao River species. • Site-specific ammonia Water Quality Criteria (WQC) were derived for Liao River. • No significant species sensitivity difference between Liao and international taxa. • International toxicity data is suitable for WQC where site-specific data is poor. [ABSTRACT FROM AUTHOR]

Water quality criteria (WQC) are considered to be an effective management tool for protecting aquatic environments. To derive site-specific WQC for an area, local data based on local species are essential to improve the applicability of WQC derived. Due to the paucity of local fish data available for the development of site-specific WQC for the Liao River, China, four local and widespread fishes ( Pseudorasbora parva ， Abbottina liaoningensis , Ctenogobius giurinus , and Misgurnus anguillicaudatus ) were chosen to test their sensitivities to ammonia, cadmium and nitrobenzene. These compounds are common and regularly-measured pollutants in Chinese rivers. In addition to the published data for species resident in the Liao River, site-specific WQC for the three chemicals were derived using both a log-logistic species sensitivity distribution (SSD) and the method recommended by the USEPA, in line with current best practice, which were then compared with Chinese national WQC. It was found that A. liaoningensis was the most sensitive, followed, in order, by P. parva , C. giurinus and M. anguillicaudatus was the least sensitive, and this trend was the same to all three chemicals tested. When comparing the SSD derived solely from previously-published data with that including our data on local fish, there were significant differences identified among parameters describing the SSD curves for ammonia and nitrobenzene and significant differences were detected for site-specific WQC derived for all of the three chemicals. Based on the dataset with local fish data taxa, site-specific WQC of Liao River for ammonia, cadmium, and nitrobenzene were derived to be 20.53 mg/L (at a pH of 7.0 and temperature of 20 °C), 3.76 μg/L (at a hardness of 100 mg/L CaCO 3 ), and 0.49 mg/L, respectively. Using the same deriving method for each chemical, the national Chinese WQC were higher than site-specific WQC derived in this study for ammonia (national WQC of 25.16 mg/L) and nitrobenzene (national WQC of 0.57 mg/L), while the national WQC for cadmium was lower (national WQC of 1.81 μg/L). These results indicated that published data can be helpful for use when deriving site-specific WQC but that there were differences between site-specific and national WQC which may lead to either over- or under-protection depending on the pollutant if national WQC were used as the basis for the water management of specific river systems, like the Liao River. [ABSTRACT FROM AUTHOR]

The aims of this study were to evaluate the bioavailability of polycyclic aromatic hydrocarbons (PAHs) in industrial and agricultural soils using chemical methods and a bioassay, and to study the relationships between the methods. This was conducted by comparing the quantities of PAHs extracted from two manufactured gas plant (MGP) soils and an agricultural soil with low level contamination by solid-phase micro-extraction (SPME) and Tenax-TA extraction with the quantities taken up by the earthworm ( Eisenia fetida ). In addition, a biodegradation experiment was conducted on one MGP soil (MGP-A) to clarify the relationship between PAH removal by biodegradation and the variation in PAH concentrations in soil pore water. Results demonstrated that the earthworm bioassay could not be used to examine PAH bioavailability in the tested MGP soils; which was the case even in the diluted MGP-A soils after biodegradation. However, the bioassay was successfully applied to the agricultural soil. These results suggest that earthworms can only be used for bioassays in soils with low toxicity. In general, rapidly desorbing concentrations extracted by Tenax-TA could predict PAH concentrations accumulated in earthworms (R 2 =0.66), while SPME underestimated earthworm concentrations by a factor of 2.5. Both SPME and Tenax extraction can provide a useful tool to predict PAH bioavailability for earthworms, but Tenax-TA extraction was proven to be a more sensitive and precise method than SPME for the prediction of earthworm exposure in the agricultural soil. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we study the asymptotic behavior of solutions of non-autonomous parabolic problems with singular initial data. We first establish the well-posedness of the equation when the initial data belongs to () and (), respectively. When the initial data belongs to , we establish the existence of uniform attractors in for the family of processes with external forces being translation bounded but not translation compact in . When we consider the existence of uniform attractors in , the solution of equation lacks the higher regularity, so we introduce a new type of solution and prove the existence result. For the long time behavior of solutions of the equation in , we only obtain the uniform attracting property in the weak topology. [Copyright &y& Elsevier]

To reduce the size of Ni(OH) 2 aggregates is an effective way to improve their capacitive performance for the electrodes of supercapacitors. The ultrasmall Ni(OH) 2 aggregates (1–2 nm) on active carbon (AC) can be obtained by depositing the soluble precursor of Ni(OH) 2 on AC at low temperature. The Ni(OH) 2 /AC samples were characterized by SEM, TEM, XRD and XPS. The specific capacitance of ultrasmall Ni(OH) 2 aggregates in the Ni(OH) 2 /AC composite can reach 2949 F g −1 at a scan rate of 20 mV s −1 , which is higher than its theoretical specific capacitance (2382 F g −1 ). Ni(OH) 2 aggregates supported on carbon cloth can also exhibit superior specific capacitance as a bind-free flexible electrode. The capacitive, rate and cycling performance of ultrasmall Ni(OH) 2 aggregates on AC are excellent, revealing the great potential of ultrasmall sized materials in energy storage. [ABSTRACT FROM AUTHOR]

The lack of treatment systems for pollutants in family-livestock and poultry sites results in large amounts of untreated manure and urine being directly discharged to environment. The risks from veterinary antibiotic (VA) and heavy metal (HM) exposure in the rural environment require further research. In this investigation, 221 samples (feed, manure, surface soil, soil profiles, water, and plant) were collected from 41 livestock and poultry farms (swine, chichen, and cattle). Copper (Cu), zinc (Zn), oxytetracycline (OTC), and enrofloxacin (ENR) were frequently detected in the samples. Metals and VAs in sandy loam soils were more inclined to migrate to deep layers than those in loam soils. Copper and Zn in the polluted soils mainly existed in available forms, which facilitated their migration to deep soil layers. In this study, OTC was also observed to migrate more easily to deeper soil layers than ENR due to its relatively high pKa value. Eighteen antibiotic resistance genes (ARGs) and 5 metal resistance genes (MRGs) along with one mobile genetic element (MGE) occurred in the soils at 80 cm depth. Luteimonas , Clostridium_sensu_stricto_1 , and Rhodanobacter were dominant genera detected in the soil samples from different sites, which might increase migration of ARGs or degradation of VAs. An ecological risk assessment suggested that VAs posed threats to the growth of Triticum aestivum L, Cucumis sativus L, and Brassiaca chinensis L. Remediation techniques including biochar/modified biochar, anaerobic digestion, and manure composting should be developed urgently for joint HM and VA pollution. [Display omitted] • Forty-one farmhouses were surveyed for heavy metals and antibiotics. • Antibiotics and resistance genes migrated in soils at depths of 0–80 cm. • Accumulation of antibiotics could be higher than their dissipation. • Heavy metals and antibiotics may induce similarities in microbial communities. [ABSTRACT FROM AUTHOR]