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MAUSAM ◽  
2022 ◽  
Vol 53 (4) ◽  
pp. 481-486
Author(s):  
P. K. NANDANKAR

The present study aims at seasonal and diurnal pollution potential at Gorakhpur in east Uttar Pradesh. To assess the pollution potential, meteorological data for five year period (1982-86) of Gorakhpur have been analyzed for four seasons viz; winter (December-February), summer (March-May), monsoon (June-September) and post monsoon (October-November). Season wise wind roses, stability, stability wind roses have been prepared and season wise diurnal variation of mixing height and ventilation coefficient have also been worked out. It is found that Gorakhpur has a better diffusion capacity in summer and poor in post monsoon followed by winter. Afternoon hours are better for vertical mixing. The winds are predominantly from southwest to west in all seasons except in monsoon when it blows from northeast to east. Based on this study, an appropriate location for industrialization has been suggested.


2022 ◽  
Vol 22 (1) ◽  
pp. 371-393
Author(s):  
Baoye Hu ◽  
Jun Duan ◽  
Youwei Hong ◽  
Lingling Xu ◽  
Mengren Li ◽  
...  

Abstract. Because nitrous acid (HONO) photolysis is a key source of hydroxyl (OH) radicals, identifying the atmospheric sources of HONO is essential to enhance the understanding of atmospheric chemistry processes and improve the accuracy of simulation models. We performed seasonal field observations of HONO in a coastal city of southeastern China, along with measurements of trace gases, aerosol compositions, photolysis rate constants (J), and meteorological parameters. The results showed that the average observed concentration of HONO was 0.54 ± 0.47 ppb. Vehicle exhaust emissions contributed an average of 1.45 % to HONO, higher than the values found in most other studies, suggesting an influence from diesel vehicle emissions. The mean conversion frequency of NO2 to HONO in the nighttime was the highest in summer due to water droplets evaporating under high-temperature conditions. Based on a budget analysis, the rate of emission from unknown sources (Runknown) was highest around midday, with values of 4.51 ppb h−1 in summer, 3.51 ppb h−1 in spring, 3.28 ppb h−1 in autumn, and 2.08 ppb h−1 in winter. Unknown sources made up the largest proportion of all sources in summer (81.25 %), autumn (73.99 %), spring (70.87 %), and winter (59.28 %). The photolysis of particulate nitrate was probably a source in spring and summer while the conversion from NO2 to HONO on BC enhanced by light was perhaps a source in autumn and winter. The variation of HONO at night can be exactly simulated based on the HONO / NOx ratio, while the J(NO3-_R) × pNO3- should be considered for daytime simulations in summer and autumn, or 1/4× (J(NO3-_R) × pNO3-) in spring and winter. Compared with O3 photolysis, HONO photolysis has long been an important source of OH except for summer afternoons. Observation of HONO across four seasons with various auxiliary parameters improves the comprehension of HONO chemistry in southeastern coastal China.


Author(s):  
Weijun Guo ◽  
Jibing Zou ◽  
Sihong Liu ◽  
Xuewen Chen ◽  
Xiangpeng Kong ◽  
...  

Spatial–seasonal variations in dissolved heavy metals in surface seawater were analyzed based on surveys at 87 sampling sites and water samples from six rivers across Liaodong Bay. The concentrations of copper (Cu), lead (Pb), cadmium (Cd), and zinc (Zn) had ranges of 0.20–40.00 (5.45 ± 5.67), 0.51–33.64 (4.68 ± 3.93), 0.03–13.47 (2.22 ± 2.01), and 0.50–80.09 μg/L (14.22 ± 16.32), respectively, throughout the four seasons of 2020. The trace metal concentration showed a spatial gradient of high to low from river to estuary and from inshore to offshore areas. A combination of pollution levels and marine sensitivity was employed to assess the pollution degree of the heavy metals. As a whole, the single pollution factors of trace metals in Liaodong Bay were ranged in the order Pb > Zn > Cu > Cd. The total pollution degree was relatively high in autumn and summer due to increased riverine inputs after the rainy season, while relatively low in spring and winter. These findings provide baseline data for future targeting policies to protect marine environments in Liaodong Bay.


PeerJ ◽  
2022 ◽  
Vol 9 ◽  
pp. e12705
Author(s):  
Guangjie Fang ◽  
Haolin Yu ◽  
Huaxiang Sheng ◽  
Chuanxi Chen ◽  
Yanli Tang ◽  
...  

Marine bacteria in the seawater and seafloor are essential parts of Earth’s biodiversity, as they are critical participants of the global energy flow and the material cycles. However, their spatial-temporal variations and potential interactions among varied biotopes in artificial habitat are poorly understood. In this study, we profiled the variations of bacterial communities among seasons and areas in the water and sediment of artificial reefs using 16S rRNA gene sequencing, and analyzed the potential interaction patterns among microorganisms. Distinct bacterial community structures in the two biotopes were exhibited. The Shannon diversity and the richness of phyla in the sediment were higher, while the differences among the four seasons were more evident in the water samples. The seasonal variations of bacterial communities in the water were more distinct, while significant variations among four areas were only observed in the sediment. Correlation analysis revealed that nitrite and mud content were the most important factors influencing the abundant OTUs in the water and sediment, respectively. Potential interactions and keystone species were identified based on the three co-occurrence networks. Results showed that the correlations among bacterial communities in the sediment were lower than in the water. Besides, the abundance of the top five abundant species and five keystone species had different changing patterns among four seasons and four areas. These results enriched our understanding of the microbial structures, dynamics, and interactions of microbial communities in artificial habitats, which could provide new insights into planning, constructing and managing these special habitats in the future.


2022 ◽  
Vol 82 ◽  
Author(s):  
W. A. Chiba de Castro ◽  
R. C. Luz ◽  
C. K. Peres

Abstract As a result of biodiversity and ecosystem service losses associated with biological invasions, there has been growing interest in basic and applied research on invasive species aiming to improve management strategies. Tradescantia zebrina is a herbaceous species increasingly reported as invasive in the understory of disturbed forest ecosystems. In this study, we assess the effect of spatial and seasonal variation on biological attributes of this species in the Atlantic Forest. To this end, we measured attributes of T. zebrina associated with plant growth and stress in the four seasons at the forest edge and in the forest interior of invaded sites in the Iguaçu National Park, Southern Brazil. The invasive plant had higher growth at the forest edge than in the forest interior and lower leaf asymmetry and herbivory in the winter than in the summer. Our findings suggest that the forest edge environment favours the growth of T. zebrina. This invasive species is highly competitive in the understory of semi-deciduous seasonal forests all over the year. Our study contributes to the management of T. zebrina by showing that the summer is the best season for controlling this species.


2022 ◽  
Vol 40 ◽  
Author(s):  
Catiane Zanin Cabral ◽  
Alan da Silveira Fleck ◽  
Fernanda Chaves Amantéa ◽  
Claudia Ramos Rhoden ◽  
Sérgio Luis Amantéa

Abstract Objective: To evaluate air quality in the waiting room of a pediatric emergency service considering the serial concentrations of particulate matter (PM2.5), and to determine if the number of people present in the room can have an influence on the pollutant concentrations. Methods: Cross-sectional study, carried out in the waiting room of a reference pediatric hospital in the city of Porto Alegre, conducted in a one-year period, in a continuous-time sample including all of the four seasons of the year. The monitoring of PM2.5 was performed using a real-time aerosol monitor (DustTrak II). The number of people in the room was determined every hour and the climatic characteristics per daily mean. The concentration of PM2.5 and the number of people were expressed by mean and standard deviation. The means were compared by Analysis of Variance and Pearson's correlation coefficient. Results: There was a significant increase in the concentration of PM2.5 in the autumn, when compared to other seasons (p<0.001). The pollutant increase, in this season, was accompanied by the higher number of people in the emergency room (p=0.026). The association between PM2.5 and the number of people is confirmed by the positive correlation between these two variables (r=0.738; p<0.001). Conclusions: The pediatric emergency waiting room showed elevated PM2.5 in all seasons. The number of people in the room had a positive correlation with the concentration of the pollutant in the environment.


2022 ◽  
pp. 107-129
Author(s):  
Carlos Raul Navarro González ◽  
Yanet Villarreal González ◽  
Pedro Alberto Escárcega Zepeda ◽  
Ana Laura Sanchez Corona ◽  
Rigoberto Zamora Alarcon ◽  
...  

The objective of this research was developed to evaluate the working conditions of workers in an electronic industry located in the city of Mexicali, analyzing a process in a work table where welding operations of electronic components are made and certain factors are presented that generated discomfort to the operating personnel of this manufacturing area. The workers frequently visited the company doctor and health institutions in Mexicali due to symptoms of discomfort and pain in the head, neck, back, spine, arms, hands, and shoulders in addition to discomfort in the eyes due to not having a position due to poor structure (work table and chair) and low light intensity, which caused fatigue and stress and discomfort with eyestrain. In addition, certain employees in the production areas presented symptoms of respiratory diseases caused by an environment contaminated by pollutants, essentially derived from sulfur (sulfides), as well as variations in temperature and relative humidity in the four seasons of the year.


2022 ◽  
Vol 5 (1) ◽  
pp. 29-38
Author(s):  
Sibel Bayar ◽  
Ercan Akan

Our country is surrounded by seas on three sides; it is in an attractive position in terms of tourism due to its suitable climate and many history and cultures. Especially the stagnant structure of the Aegean and the Mediterranean allows sea tourism in almost four seasons; it is one of the routes preferred especially by yacht ships. In this respect, a maritime traffic arises due to touring, sports and recreational ships and yachts, and these ships occasionally cause accidents. In the study, marine accidents in the Turkish Search and Rescue Area involving touring, sports and recreational vessels and yachts are statistically analyzed. In this context, frequency distributions are carried out first and the hypotheses are examined by Chi-Square independence analysis.


2021 ◽  
Vol 1 (1) ◽  
pp. 1-14
Author(s):  
Ömer K. ÖRÜCÜ ◽  
Atila GÜL

Eğirdir districts is rich in natural and historical environmental values and cultural traits are the important places of tourism and recreational activities. Tourism and recreational activities, which are developed in regards with the atractiveness of such places, are made of those natural and cultural environment. When events of tourism all over the world are examined, it could be observed that such activities usually take place during summer months. However, since developing residences and facilities tend to use sources more than before, they affect natural, historical and the cultural values negatively and thus corruption starts. Inspite of the fact that the district is gradually getting more intensive in terms of tourism and recreation during the four seasons, there haven’t been any serious problems yet. In the areas of these natural and cultural resources, the problems related with the use of those resources where tourism and recreational activities are concentrated can not be ignored and the purpose of this study is what can be done to prevent the spread of such problems of the district. In this study, natural and cultural traits to be developped in the district of Eğirdir have been investigated and analized in order to detect the tourism and the recreational potentials in the region.


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