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This study investigates the feasibility of a relevance vector machine tuned with improved Manta-Ray foraging optimization (RVM-IMRFO) in predicting monthly pan evaporation using limited climatic input data (e.g. temperature). The accuracy of the RVM-IMRFO was evaluated by comparing it with RVM tuned by gray wolf optimization, RVM tuned with a whale optimization algorithm, and RVM tuned with Manta Ray foraging optimization concerning root mean square errors (RMSE), mean absolute errors (MAE), determination coefficient (R²) and Nash-Sutcliffe Efficiency (NSE) and new graphical inspection methods. The models were assessed using data acquired from two stations in China and data were divided into three equal parts. The models were tested using each data set. The application outcomes revealed that the proposed algorithm considerably improved the accuracy of a single RVM in monthly pan evaporation prediction by an average improvement in RMSE, MAE, R², and NSE as 27.65%, 27.53%, 8.40% and 8.63%, respectively. It is also found that the proposed algorithm showed significant dominance over others models with respect to improvement in overall mean values of RMSE, MAE, R², and NSE statistics from 34.7-38.2 to 18.2-19.5, 36.2-36.4 to 19.1-18.5, 12.5-13.8 to 3.6-3.7, and 12.4-14.6 to 3.6-3.9%, for both climatic stations, respectively. Importing extraterrestrial radiation and periodicity component (month number of the data) into the model inputs improved the prediction accuracy of the implemented models. The outcomes revealed that the RVM-IMRFO performed superior to the other methods in predicting monthly pan evaporation using only temperature data which is essential, especially in developing countries where other climatic data are missing or unavailable. The RVM model was also compared with standard multi-layer perceptron neural networks (MLPNN) and found that the first acts better than the latter in monthly pan evaporation prediction. [ABSTRACT FROM AUTHOR]

Asian leaf-litter toads of the genus Leptobrachella represent charismatic anuran diversification with 80 species, of which 25 are from China. Recent new discoveries suggest that the diversity of this genus is underestimated. Here, we describe a new species of Leptobrachella, Leptobrachella bashaensis sp. nov. from the Basha Nature Reserve, Congjiang County, Guizhou Province, China. The new species is distinguished from its congeners by the following suite of morphological traits: small body size (SVL 22.9-25.6 mm in six adult males and 27.1 mm in one adult female); head longer than wide; dorsal skin slightly shagreened with small tubercles; creamy-white chest and belly with irregular black spots; distinct ventrolateral glands forming a white line; finger webbing and fringes absent; toe webbing rudimentary and lateral fringes narrow; iris bicolored with bright orange in upper half and silver in lower half; dorsal surface of tadpole head dark brown with small, brown, irregular spot, air sac-shaped bulges on both sides of body. The new species differs from all known congeners by an uncorrected p-distance of >5.3% of the 16S rRNA gene fragment examined, and the phylogenetic analysis clusters the new species with L. maoershanensis and L. laui. At present, the new species is only known from a small range of montane evergreen secondary forests in Basha Nature Reserve approximately 900 m elevation. Its natural history and conservation status are discussed. [ABSTRACT FROM AUTHOR]

Knowledge of aerosol chemistry in densely populated regions is critical for effective reduction of air pollution, while such studies have not been conducted in Changzhou, an important manufacturing base and populated city in the Yangtze River Delta (YRD), China. This work, for the first time, performed a thorough chemical characterization on the fine particulate matter (PM2.5; samples, collected during July 2015 to April 2016 across four seasons in this city. A suite of analytical techniques was employed to measure the organic carbon (OC), elemental carbon (EC), watersoluble organic carbon (WSOC), water-soluble inorganic ions (WSIIs), trace elements, and polycyclic aromatic hydrocarbons (PAHs) in PM2.5; in particular, an Aerodyne soot particle aerosol mass spectrometer (SP-AMS) was deployed to probe the chemical properties of water-soluble organic aerosol (WSOA). The average PM2.5 concentration was found to be 108.3 μgm-3, and all identified species were able to reconstruct ∼80% of the PM2.5 mass. The WSIIs occupied about half of the PM2.5 mass (∼52.1%), with SO2-4, NO-3, and NHC 4 as the major ions. On average, nitrate concentrations dominated over sulfate (mass ratio of 1.21), indicating that traffic emissions were more important than stationary sources. OC and EC correlated well with each other and the highest OC/EC ratio (5.16) occurred in winter, suggesting complex OC sources likely including both secondary and primary ones. Concentrations of eight trace elements (Mn, Zn, Al, B, Cr, Cu, Fe, Pb) can contribute up to ∼5.0%of PM2.5 during winter. PAH concentrations were also high in winter (140.25 ngm-3), which were predominated by median/high molecular weight PAHs with five and six rings. The organic matter including both watersoluble and water-insoluble species occupied ∼21.5% of the PM2.5 mass. SP-AMS determined that the WSOA had average atomic oxygen-to-carbon (O = C), hydrogen-to-carbon (H = C), nitrogen-to-carbon (N = C), and organic matter-toorganic carbon (OM = OC) ratios of 0.54, 1.69, 0.11, and 1.99, respectively. Source apportionment of WSOA further identified two secondary OA (SOA) factors (a less oxidized and a more oxidized oxygenated OA) and two primary OA (POA) factors (a nitrogen-enriched hydrocarbon-like traffic OA and a local primary OA likely including species from cooking, coal combustion, etc.). On average, the POA contribution outweighed SOA (55% vs. 45%), indicating the important role of local anthropogenic emissions in the aerosol pollution in Changzhou. Our measurement also shows the abundance of organic nitrogen species in WSOA, and the source analyses suggest these species are likely associated with traffic emissions, which warrants more investigations on PM samples from other locations. [ABSTRACT FROM AUTHOR]

Particle size distribution down to 1.4 nm was measured in the urban atmosphere of Nanjing, China, in spring, summer, and winter during 2014-2015. Sub-3 nm particle event, which is equivalent to nucleation event, occurred on 42 out of total 90 observation days, but new particles could grow to cloud condensation nuclei (CCN)-active sizes on only 9 days. In summer, infrequent nucleation was limited by both unfavorable meteorological conditions (high temperature and relative humidity - RH) and reduced anthropogenic precursor availability due to strict emission control measures during the 2014 Youth Olympic Games in Nanjing. The limiting factors for nucleation in winter and spring were meteorological conditions (radiation, temperature, and RH) and condensation sink, but for the further growth of sub-3 nm particles to CCN-active sizes, anthropogenic precursors again became limiting factors. Nucleation events were strong in the polluted urban atmosphere. Initial J1.4 at the onset and peak J1.4 at the noontime could be up to 2.1 10² and 2.5 10³ cm-3 s-1, respectively, during the eight nucleation events selected from different seasons. Time-dependent J1.4 usually showed good linear correlations with a sulfuric acid proxy for every single event (R² = 0.56-0.86, excluding a day with significant nocturnal nucleation), but the correlation among all eight events deteriorated (R² = -0.17) due to temperature or season change. We observed that new particle growth rate (GR) did not increase monotonically with particle size, but had a local maximum up to 25 nm h-1 between 1 and 3 nm. The existence of local maxima GR in sub-3 nm size range, though sensitive to measurement uncertainties, gives new insight into cluster dynamics in polluted environments. In this study such growth rate behavior was interpreted as the solvation effect of organic activating vapor in newly formed inorganic nuclei. [ABSTRACT FROM AUTHOR]

This article focuses on a study which simulated the performance of a full-scale sequencing batch reactor (SBR) plant for municipal wastewater treatment. Particular focus is given to the modified Activated Sludge Model No. 3 (ASM3), along with the components of the Zhuzhuanjing wastewater treatment plant in Hefei City, China. Results of the study showed that the influent chemical oxygen demanded (COD) fraction did not change substantially from the average values. It also identified the key to obtaining high-quality effluent.