Forest structure and regeneration of Betula utilis (D. Don) was studied in birch forest located in Samagaun valley (3500 -4000 m) of Manaslu Conservation Area. Vegetation sampling was done by quadrat method. Altogether 40 quadrats were sampled to determine the Importance Value Index (IVI) of tree species, and distribution pattern of seedlings and saplings. Regeneration was assessed by density -diameter curve. Four tree species were recorded from the forest. Betula utilis was the dominant tree species with the highest Importance Value Index (173.22) in mixed Betula forest and 262.96 in pure Betula forest and Abies spectabilis was the co -dominant species (65.95) in mixed Betula forest while Rhododendron campanulatum was the co-dominant species (37.03) in pure Betula forest. Density of Betula utilis increased with increase in elevation where as density of other tree species decreased with increase in elevation. Mixed Betula forest at lower elevation was young. The density diameter curve of the tree population of Betula utilis, both on mixed and pure forests, deviated slightly from the typical reverse J shaped structure and hence did not show the sustainable regeneration. The sapling density was higher than seedling density. The distribution of seedlings and saplings were not uniform among the sampling plots.

Water borne infections in Nepal, especially in Kathmandu valley is one the major public health problems, causing thousands of deaths every year. Among three cities in the valley, the water borne infection including cholera is most predominant in Bhaktapur district. So the study was carried out to know the microbial drinking water quality in the city and to determine the prevalence of water borne infections in the specified region of the district in 2012. Altogether eighty (two samples from a single site at different interval-2/3 days) water samples were collected from Bhaktapur Municipality, one of the most vulnerable regions for water borne diseases, following standard methods as described by APHA, 2010. All samples were transferred to Microbiology laboratory of Khwopa College, Dekocha, Bhaktapur and preceded immediately for Microbial analysis. The coliform density in the water samples were determined by Most Probable Number (MPN) method followed by microscopy, colonial morphology and biochemical characterization. Subsequently, the presence of Vibrio cholerae, a causative agent of Cholera was analyzed in the same samples by enrichment in alkaline peptone water followed by culture on Thiosulphate citrate bile-salt sucrose (TCBS) agar, a selective media for Vibrio spp. The biochemical tests were then performed to identify V. cholerae. Among eighty water samples, 87.5 percent water samples contained coliforms and half of which (45%) contained feacal coliforms, Escherichia coli and remaining 12.5 percent water samples contained no coliforms. Vibrio cholerae were isolated from four water samples (5%). The drinking water quality in the region was found to be very poor. Therefore, the people in the region were suggested to treat the drinking water by using any of physical or chemical disinfection methods prior to drinking.

Vehicular emissions have been playing a pivotal role in deteriorating air quality in many urban parts of Nepal causing adverse impacts upon the health of commuters and pedestrians attributed to severe respiratory diseases. Primary data such as the number of vehicles (N) were obtained using two-hour peak (8 am to 10 am) and two-hour nonpeak (1 pm to 3 pm) count, after which average annual vehicle kilometer (VKT) and fuel economy (F) required for emission load estimation were obtained from vehicle survey using the simple random sampling method, sampling size taken statistically under 5% margin of error. Secondary data in this study include emission factors and derived equations from a published article. The vehicular emission load of Bhaktapur Municipality were found to be 3,310 tons/year including CO2, CO, NOx, HC, and PM10 of which CO2 accounts for 94.36% of total emissions followed by CO (4.39%), HC (0.72%), NOx (0.35%), and PM10 (0.18%), respectively. Significant positive correlation was found (r = 0.92, p = 0.002 ) between CO2 and PM10 (r = 0.87, p = 0.009 ), between CO2 and NOx (r = 0.90, p = 0.004 ), between CO and HC (r = 0.74, p = 0.05 ), and between NOx and PM10, respectively. The scenario analysis shows that the introduction of electric vehicles at different rates within the municipality can reduce the emissions to a significant amount. Exponential growth in vehicular gaseous pollutants potent to jeopardize the environment and welfare can become inevitable in the future if clean energy technology is not promoted early.

Bottled water is generally considered safe for drinking. However, several studies have reported the substandard quality of bottled water. Physico-chemical assessment of ten different brands of bottled water distributed in Bhaktapur Municipality was carried out from January 2018 to March 2018. In total, one hundred bottled water samples consisting of ten different brands were collected randomly from various retail outlets.Eight selected physico-chemical and microbiological parameters were analysed following standard methods, and the results were compared with the Nepal Drinking Water Quality Standard (NDWQS) (2005). Out of one hundred samples, sixty-nine samples did not comply with the standard pH limit. Other physico-chemical parameters were found to comply with the standard though variations were observed in the concentrations among different brands. Microbial contamination was not found in any brands of the bottled water samples considered in this study. However, it is necessary to examine other contaminants such as heavy metals, minerals, and chemicals to know the overall quality of water. Moreover, the regulatory bodies are required to strictly monitor water processing companies for the maintenance of the quality of bottled water. brand name, manufacture and expiry date were also inspected in the collected samples.Bhaktapur Municipality has ten wards. Therefore, to cover all the municipal territory in the sampling process, at least one sample of each brand of bottled water was collected from each ward. A simple random sampling technique was used to choose a particular retail outlet such as a department store, grocery shop, restaurant, and canteen. A total of one hundred number of bottled water samples (ten samples from each brand) were