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Volatile organic compounds (VOCs) are the main precursors of pollution from ground ozone (O3) and PM2.5, which cause the deterioration of urban air quality. The emissions of VOCs from industrialized areas are significant and their characteristics are complex, which nowadays contribute significantly to the challenges of investigating the emission inventory. Taking a typical industrialized area in Tianjin as a case study, the anthropogenic VOCs emission inventory for 2020 was established in this study by using the activity data from a large-scale survey and the latest emission factors. The impact of VOCs on the environment was analyzed from the perspective of the combined control of PM2.5 and O3. The results showed that the total emission of VOCs in 2020 was about 1.68 Gg, mainly from industrial processes and mobile sources, which accounted for 38.4% and 36.5% of the total emissions, respectively. The top 10 emitted VOCs were toluene, acetone, ethylbenzene, m/p-xylene, i-pentane, n-hexane, formaldehyde, benzene, ethyl acetate and ethylene. The dominant species of O3 formation potential (OFP) were almost all aromatic hydrocarbons and alkenes, with m/p-xylene contributing the most to the OFP emissions (8.90%). The top 10 secondary organic aerosols formation potential (SOAP) emission species were aromatic hydrocarbons and long-chain alkanes, and the largest emission came from toluene (39.9%). An analysis of an ADMS diffusion model showed that VOCs emitted from traffic-heavy main roads and industrialized central areas had the greatest impact on the air quality in the surrounding areas. The VOCs concentration was higher in winter due to unfavorable meteorological conditions. Our research updated the VOC inventory of industrialized areas and evaluated VOCs species reactivity and their impact on ambient air quality. [ABSTRACT FROM AUTHOR]

We report here the first application of the Spatially Referenced Regressions on Watershed Attributes (SPARROW) model to China, a country naturally and culturally distinct from previous SPARROW applications. The Songhuajiang River Basin (556,700 km) empties into the Tongjiang monitoring section, a shared water resource of great import for both Chinese and Russian citizens. The model was calibrated to annual loads of total nitrogen (TN) at 102 sites and total phosphorus (TP) at 65 sites. We assessed the rates of delivery and loss of nutrients from diffuse sources and also provided reach-level predictions of the percentage of nutrient loads delivered from upstream subbasins to Tongjiang monitoring section. The results indicated that farmland and pasture land were responsible for about 70 % of nutrient inputs to the Tongjiang monitoring section. Point source inputs were not statistically significant sources of TN or TP. We presented evidence that rice paddies delivered less TN to streams per area than other types of cropland. The locations responsible for the highest TN and TP inputs to the Tongjiang monitoring section tended to be located near the mainstream, though the areas of highest TN delivered yield did not correspond to the areas of highest TP delivered yield. This suggests that different management priorities may be needed in different parts of the Songhuajiang River Basin. [ABSTRACT FROM AUTHOR]

Schizopygopsis chengi baoxingensisis endemic to the Baoxing River in China and may become an endangered species due to its very narrow habitat and the construction of hydropower dams. In this study, we successfully sequenced the first mitochondrial genome ofS. c. baoxingensis. The mitogenome is 16,787 bp in length, containing 13 protein-coding genes, two rRNA genes, 22 tRNA genes and a control region (D-loop). The overall base composition of the H-strand is 28.5% A, 26.2% T, 18.4% C, and 26.9% G, with a slight AT bias of 54.7%. The sequenced mtDNA genome ofS. c. baoxingensisis similar in gene arrangement to that of other cyprinidaes except for a 191 bp non-coding region found betweentRNAThrandtRNAPro. [ABSTRACT FROM PUBLISHER]

The Elongate loach ( Leptobotia elongata) belongs to family Cobitidae, which is endemic to the middle and upper reaches of the Yangtze River in China. In this study, the complete mitochondrial genome of L. elongata was sequenced. It was determined to be 16,591 bases. The nucleotide sequence data of 12 heavy-strand protein-coding genes of L. elongata and other 12 Cobitidae species were used for phylogenetic analyses. Trees constructed using Bayesian and maximum parsimony showed a similar topology demonstrating that L. elongate was clustered in subfamily Botiinae being sister to the subfamily Cobitinae. The trees also suggested that the genera Cobitis were polyphyletic. [ABSTRACT FROM AUTHOR]

The beardless sucking bard,Garra imberba, is an important economic freshwater fish with very limited yield. In this study, we successfully sequenced the first mitochondrial genome ofG. imberbaby PCR. The mitogenome is 16,600 bp in length, containing 13 protein-coding genes, two rRNA genes, 22 tRNA genes and a control region (D-loop). The overall base composition of the H-strand is 31.5% A, 26.7% T, 16.1% C, and 25.8% G, with a slight AT bias of 58.2%. Most of the genes are encoded on heavy strand, except for eight tRNAs (tRNAGln, tRNAAla, tRNAAsn, tRNACys, tRNATyr, tRNASer, tRNAGlu and tRNAPro) andND6genes. [ABSTRACT FROM PUBLISHER]

The Liobagrus marginatus is an economic fish which distribute in the upstream of Yangtze river and its distributary. For its taste fresh, environmental pollution and overfishing, its population declined drastically and body miniaturization in recent decades, so it is essential to protect its resource. In this study, the complete mitochondrial genome sequence of Liobagrus marginatus was sequenced, which contains 22 tRNA genes, 13 protein-coding genes, 2 rRNA genes, and a non-coding control region with the total length of 16,497 bp. The gene arrangement and composition are similar to most of other fish. Most of the genes are encoded on heavy-strand, except for eight tRNA and ND6 genes. Just like most other vertebrates, the bias of G and C has been found in statistics results of different genes/regions. The complete mitochondrial genome sequence of Liobagrus marginatus would contribute to better understand population genetics, evolution of this lineage, and will help administrative departments to make rules and laws to protect it. [ABSTRACT FROM AUTHOR]