Nepal Journal of Environmental Science

Morphological and elemental analysis of termite mound and ant nest in agriculturally prominent area

2022-10-31T16:36:38+00:00

Soil management is important for the farmers to improve the crop yield. In nature some invertebrates serve as bioindicators and biomonitors. Biogenic structure built by insects is important for controlling soil erosion and water reserves. Ants and termites nest architecture along with the elemental analysis was studied to evaluate soil health and possible threats imposed by heavy metals in the area. The soil samples were collected and analyzed for various parameters. Systematic study of porosity, composition, and nutritional values of soil in ant nest and termite mound were done. The Atomic Absorption Spectrophotometer and Inductively Coupled Plasma Mass Spectrophotometer studies showed that ant nest and termite mound samples were found to contain elements viz., zinc, selenium, lead, cadmium, nickel drought and chromium. Based on Scanning Electron Microscope-Energy Dispersive Analysis of X-rays, the size of soil samples collected from ant nest and termite were found to be 27.77 nm and 25.56 nm, respectively. The corrosion resistant zirconium and titanium metals were detected in 0.68 and 0.39% concentration in ant nest and termite mound samples, respectively, representing the insect house as a possible source of rich metals. The ant nest and termite mound materials contain quartz, microcline, kaolinite, and clay minerals. Ant nests and termite mounds can thus be used as hydrological indicators to address the problems of soil erosion.

Trichoderma sp. for cellulase enzyme production

2022-10-31T16:10:13+00:00

The enzymes are having wide applications in various industries. The group of microorganisms, viz., bacteria, fungi, actinobacteria produces different enzymes, viz., cellulase, chitinase, amylase, protease, lecithinase, lipase, gelatinase, etc. and these enzymes have immense market demand. The work here describes isolation of Trichoderma sp. and study of their colony characteristics on different agar media. The morphology images of Trichoderma sp. were also studied light and stereo microscope. The isolated Trichoderma sp. was studied for the production of cellulase. The isolated three species of Trichoderma were found to show production of cellulase. The cellulase production was more by Trichoderma sp. isolate No. 1. The cellulase production by Trichoderma sp. will have applications in food and other industries. The production of cellulase by Trichoderma sp. will be economical and eco-friendly.

Quantification and characterization of household solid waste at Urban Area of Kathmandu

2022-12-30T09:05:47+00:00

Solid waste management can have significant positive and negative implications to the physical, social and economic environment and these implications are the function of management options adopted. The quantity and character of the waste generated changes with time and understanding these properties of waste in a locality form the basis of solid waste management. Thus, this research aims to understand the rate of solid waste generation in Kathmandu Metropolitan City, Ward 31, Shantinagar, and characterize the waste based on composition and management options. Waste generated by 100 households in 24 hours was collected, segregated, and weighed to quantify and characterize the waste generated at household level. Furthermore, an in-person interview was conducted with the household representatives using a semi-structured questionnaire to understand the options used for solid waste management at household level and their willingness to participate in waste segregation at source. The percentage composition of each waste category and per capita waste generated at household level was calculated. The relation of the per capita waste with number of family member was modeled by using linear regression. Data analysis was performed by using Microsoft Excel and R software. Significant fractions of the waste generated in the households were organic waste followed by paper waste which together makes up nearly 51% of total weight of the solid waste generated in the area. Per capita waste generation was found to be 402.7 grams per person per day. Per capita waste generation was a function of the number of family members with a decrease in per capita waste by an average of 111 g with an increase in one member in a family. Households who are involved in rooftop farming were segregating waste at the source indicating the local government can encourage rooftop farming to promote waste segregation at source.

Forecasting seasonal TDS using a normalized difference water index in the Ganges River in Bangladesh

2023-03-20T09:03:25+00:00

The Ganges is one of the most remarkable rivers in Bangladesh. The river contributes to the surface water supply, which is significantly high in the northwest region of Bangladesh. The water quality of this river changed based on many environmental events, and rainfall was one of them. The research focused on finding the mathematical relation between the field observations of water quality parameters and the observed data from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors. This study treated the Total Dissolved Solids (TDS) as one of the crucial parameters in the water quality index, which was monitored and forecasted using multiple linear regression from satellite-derived Normalized Difference Water Index (NDWI) from the Landsat imageries and Electrical Conductivity (EC) from the field observations for the pre-monsoon, monsoon, and post-monsoon periods. The predicted values returned significant correlation coefficient values compared to the field TDS values of 0.64, 0.71, and 0.52 for the three periods, respectively. The regression equations found from this study may be further utilized to predict the TDS values in the future years.

Physicochemical and microbial assessment of effluent from slaughter slab in Kirtipur Municipality, Kathmandu, Nepal

2022-12-30T15:15:52+00:00

The number of slaughterhouse facilities and retail meat shops has been on the rise, leading to an increase in the amount of wastewater they produce. Wastewater is hazardous to the environment as it causes deoxygenation in water bodies, pollutes the groundwater, and spreads several diseases if released untreated. The study was conducted in slaughter slabs and retail meat shops in Kirtipur Municipality to evaluate the physicochemical characteristics and microbial status of wastewater. Fifteen wastewater samples were collected and analyzed as per APHA-AWWA-WEF for physicochemical and total coliform count. The average values of chemical oxygen demand (COD) and biological oxygen demand (BOD) were 574.5 mg/L and 284.5 mg/L, respectively and exceeded generic standards for tolerance limits for industrial effluent. The average level of total coliform count in the fresh water and wastewater were 733 CFU/100 mL and 7.72 × 10⁴ CFU/100 mL, respectively. There is a significant difference in the total coliform count in freshwater (p value (T > t) = 0.01 < 0.05) and wastewater (p value (T>t) = 0.00 < 0.05). Slaughtering of animals without adhering to hygienic rules leads to a higher load of organic pollutants and other chemical contaminants in wastewater and has detrimental health effects on human, animal, and the environment. The slaughter slabs in Kirtipur Municipality need to be inspected during the process of slaughtering.