Variation of snow cover in the Nyang River basin of southeastern Tibetan Plateau, China

Snow cover is highly sensitive to global climate change and strongly influences the climate at global and regional scales. Because of limited in situ observations, snow cover dynamics in the Nyang River basin (NRB) have been examined in few studies. Five snow cover indices derived from observation and remote sensing data from 2000 to 2018 were used to investigate the spatial and temporal variation of snow cover in the NRB. There was clear seasonality in the snow cover throughout the entire basin. The maximum snow-covered area was 8,751.35 km2, about 50% of the total basin area, and occurred in March. The maximum snow depth (SD) was 5.35 cm and was found at the northern edge of the middle reaches of the basin. Snow cover frequency, SD, and fraction of snow cover area increased with elevation. The decrease in SD was the most marked in the elevation range of 5,000–6,000 m. Above 6,000 m, the snow water equivalent showed a slight upward trend. There was a significant negative correlation between snow cover and temperature. The results of this study could improve our understanding of changes in snow cover in the NRB from multivariate perspectives. It is better for water resources management.

Research on Operating Efficiency of Security Companies Based on Super-Efficiency DEA-Malmquist Index

In China’s economic system, security companies are important participants, and their high operating efficiency can improve the country’s economy. Based on the traditional CCR-DEA model, this paper uses super-efficiency DEA model and MALMQUIST index model to analyze the operational efficiency of 10 listed security companies in China from 2016 to 2020, it is found that the operating efficiency of security companies as a whole has a slight upward trend, and the improvement of business efficiency depends on technical efficiency, and relates to pure technical efficiency and scale efficiency.

Information Entropy Evaluation Model of Bus Line Reliability Considering the Combination of Bus Stops and Bus Travel Time

Evaluating the reliability of a bus line can provide useful information on the service performance of the city's bus transit system and the need for improvements. This paper presents a reliability evaluation model of a bus line based on information entropy. The model integrates the weighted bus-stop index and the variation index of bus travel time. To better determine the weights of the bus stop, six multiple indices were established based on three characteristics: passenger flow, bus stop properties, and the environment. The proposed model was applied to typical bus lines in Fuzhou, China. The results show that most of the bus stop reliabilities at the peak period were smaller than those at the off-peak period. Besides, for either the peak or off-peak period, the reliability shows a slight upward trend following a gradual decline after the first stop reflecting the influence of passenger flow, environment, and location factors generally.

Link between Energy Efficiency and Sustainable Economic and Financial Development in OECD Countries

The growing risk of climate change caused by the emission of greenhouse gases poses new challenges to contemporary countries. The development of economies is usually related to increasing levels of greenhouse gas emissions. Therefore, the question arises whether it is possible to achieve sustainable economic and financial development and simultaneously reduce greenhouse gas emissions. This paper assumes it is possible if energy efficiency is increased. The aim of the paper is to show the link between energy efficiency and sustainable economic and financial development in Organisation for Economic Co-operation and Development (OECD) countries for the period 2000–2018 by using data envelopment analysis (DEA) and regression analysis. The results show a slight upward trend of total factor energy efficiency (TFEE) in OECD countries for the analysed period; however, there is a difference in TFEE levels. Developed OECD countries have higher TFEE levels than developing OECD countries. The links between total factor energy efficiency and sustainable economic and financial development reveal different impacts depending on the variables taken into consideration.

Current issues of food and chemical safety of children and adolescents: acute household poisoning

Ukraine is among the countries with a high prevalence of acute chemical etiology poisoning in the countries of the European region, taking the penultimate place according to WHO (2017). The Aim of the Research. To study the risk factors for acute domestic poisoning among children and adolescents in Ukraine and to identify measures to improve it. Methods and Materials. The annual statistical reports of WHO, the data of the State Statistics Committee of Ukraine, the Center for Medical Statistics of the Ministry of Healthcare of Ukraine, and statistics of the Department of acute poisoning of the NCSH «Okhmatdyt» were analyzed. Research methods: system approach and benchmarking were applied. Results and Discussion. A comparative estimate of the incidence of acute poisoning over the last 15 years in Ukraine indicates an overall tendency for their growth as a whole: in the group of children 0–14 years, an average of 10.4% (from 13.8 ± 0.05 cases / 10000 in 1996–1998 to 15.4 ± 0.1 cases / 10000 pediatric population in 2006–2010). Among children aged 0–4 years, the rate of increase in the number of acute poisonings was the highest, i.e. it increased from 31.7 ± 0.1 to 37.1 ± 0.2 cases / 10000 of the pediatric population of this age. The incidence of primary diseases of the pediatric population, according to the data of the Injury and Poisoning statistical group, has been practically at the same level in recent years, with a slight upward trend. Thus, over the last 20 years the incidence has fluctuated within 39.6–51.4 cases / 10000 population. Conclusions. An important factor in the emergence of household poisoning is the lack of motivation of the population, including children and adolescents, to lead a healthy lifestyle (including maintaining a healthy diet). Key Words: chemical safety, food safety, toxicology, acute poisoning.

The younger, the better? Speech perception development in adolescent vs. adult L3 learners

Whereas the belief “the younger, the better” regarding foreign language learning seems to hold tenaciously, studies comparing learners of different starting ages attest that in instructed (as opposed to naturalistic) learning contexts, a younger age of onset does not automatically yield better results. However, little is known about how multilingual learners from different age groups develop in their non-native languages over time. The present study thus investigates the understudied domain of perceptual development with seven adolescents aged 12–13 and seven adults aged 19–39 (L1 German, L2 English) over the first year of L3 Polish instruction (tested after one, three, five, and ten months). The sound contrast under scrutiny was /v–w/, which only exists in the learners’ L2 and L3. As expected, in the ABX task, adults performed better than adolescents in both languages at most testing times and generally showed a slight upward trend in both their L2 and L3 learning trajectories. For the adolescents, development was more non-linear. Further, a boosting ‘novelty effect’ was found for the younger learner group: After only a few hours of L3 instruction, they perceived the contrast more consistently and faster than in L2 and at any other testing time, performing within the adults’ range.

Comparative Analysis of Long-Term Variation Characteristics of SO2, NO2, and O3 in the Ecological and Economic Zones of the Western Sichuan Plateau, Southwest China

Sulfur dioxide (SO2), nitrogen dioxide (NO2), and ozone (O3) are important atmospheric pollutants that affect air quality. The long-term variations of SO2 and NO2 in 2008–2018 and O3 in 2015–2018 in the relatively less populated ecological and economic zones of Western Sichuan Plateau, Southwest China were analyzed. In 2008–2018, the variations in SO2 and NO2 in the ecological zone were not significant, but Ganzi showed a slight upward trend. SO2 decreased significantly in the economic zone, especially in Panzhihua, where NO2 changes were not obvious. From 2015 to 2018, the concentration of O3 in the ecological zone increased significantly, while the economic zone showed a downward trend. The rising trend of the concentration ratio of SO2 to NO2 in the ecological zone and the declining trend in the economic zone indicate that the energy consumption structure of these two zones is quite different. The lower correlation coefficients between NO2 and O3 in the Western Sichuan Plateau imply that the variations of O3 are mainly affected by the regional background. The effects of meteorological factors on SO2, NO2, and O3 were more obvious in the economic zone where there are high anthropometric emissions.

SWAT-Based Runoff Simulation and Runoff Responses to Climate Change in the Headwaters of the Yellow River, China

Runoff in snowy alpine regions is sensitive to climate change in the context of global warming. Exploring the impact of climate change on the runoff in these regions is critical to understand the dynamics of the water cycle and for the improvement of water resources management. In this study, we analyzed the long-term variations in annual runoff in the headwaters region of the Yellow River (HRYR) (a typical snowy mountain region) during the period of 1956–2012. The Soil and Water Assessment Tool (SWAT) with different elevation bands was employed to assess the performance of monthly runoff simulations, and then to evaluate the impacts of climate change on runoff. The results show that the observed runoff for the hydrological stations at lower relative elevations (i.e., Maqu and Tangnaihai stations) had a downward trend, with rates of 1.91 and 1.55 mm/10 years, while a slight upward trend with a rate of 0.26 mm/10 years was observed for the hydrological station at higher elevation (i.e., Huangheyan station). We also found that the inclusion of five elevation bands could lead to more accurate runoff estimates as compared to simulation without elevation bands at monthly time steps. In addition, the dominant cause of the runoff decline across the whole HRYR was precipitation (which explained 64.2% of the decrease), rather than temperature (25.93%).

Validation of Sentinel-3A/3B Satellite Altimetry Wave Heights with Buoy and Jason-3 Data

The validation of significant wave height (SWH) data measured by the Sentinel-3A/3B SAR Altimeter (SRAL) is essential for the application of the data in ocean wave monitoring, forecasting and wave climate studies. Sentinel-3A/3B SWH data are validated by comparisons with U. S. National Data Buoy Center (NDBC) buoys, using a spatial scale of 25 km and a temporal scale of 30 min, and with Jason-3 data at their crossovers, using a time difference of less than 30 min. The comparisons with NDBC buoy data show that the root-mean-square error (RMSE) of Sentinel-3A SWH is 0.30 m, and that of Sentinel-3B is no more than 0.31 m. The pseudo-Low-Resolution Mode (PLRM) SWH is slightly better than that of the Synthetic Aperture Radar (SAR) mode. The statistical analysis of Sentinel-3A/3B SWH in the bin of 0.5 m wave height shows that the accuracy of Sentinel-3A/3B SWH data decreases with increasing wave height. The analysis of the monthly biases and RMSEs of Sentinel-3A SWH shows that Sentinel-3A SWH are stable and have a slight upward trend with time. The comparisons with Jason-3 data show that SWH of Sentinel-3A and Jason-3 are consistent in the global ocean. Finally, the piecewise calibration functions are given for the calibration of Sentinel-3A/3B SWH. The results of the study show that Sentinel-3A/3B SWH data have high accuracy and remain stable.

White stork (Ciconia ciconia L.) as an indicator of natural environment status in agricultural areas, illustrated with an example of Masurian Landscape Park

The paper presents the results of a 5-year study on the population size of the white stork (Ciconia ciconia L.) as one of the indicator species used to assess a biodiversity level in agricultural areas. The study was carried out in Masurian Landscape Park situated in Warmińsko-Mazurskie Voivodeship. The results demonstrated that the white stork population size was closely linked to agricultural areas, in particular, the extensively managed permanent grassland. In the years 2014–2018, even if minor changes were observed in the land use structure, the white stork population size showed a slight upward trend within the study area. In order to maintain this status, efforts should be made to preserve open landscapes (first and foremost – meadows and pastures), which are preferred feeding grounds of white stork. Consequently, potential decision as regards afforestation and housing should be made considerately.