Environmental Science

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    Assessment of change in ground water and surface water quality in the nearby area due to solid waste at Sisdol Sanitary Landfill Site, Nuwakot
    (Department of Environment Science, 2009) Thapa Shrestha, Ujjwal
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    Characterization Of Landslide Hazard In The Sub Himalayan Zone Of Nepal
    (Institute of Science & Technology, 2023-09) Bhandari, Bharat Prasad
    Landslides are a typical geological process in the Himalayan Mountains, causing yearly loss of life and property during the Monsoon period. Active tectonism, seismic activity, monsoon rainfall, complicated geology, and steep slopes are crucial markers of the Himalayan landslide process. The Siwalik is the world's youngest mountain range, comprising fragile sedimentary rocks. Landslides are a common natural disaster in the Sub Himalayan zone (Siwalik) during the Monsoon period, resulting in the loss of lives and property. Landslide mitigation and prevention are a significant challenge in the Siwalik region. The characterization is a new issue for this region to explore and comprehend the natural process of landslides. This study aims to characterize the landslide by using geological, topographical, hydrological, and geotechnical attributes along with landslide classification and susceptibility modeling in the Babai River watershed of the Siwalik region. The procedure began with the spatial and temporal landslide inventory mapping by using Google Earth, Landsat, and Sentinel imageries. The spatial inventory map included all landslides in the study area, whereas the temporal inventory map included new landslides annually from 2010 to 2021. The size, length, area, and number of landslides in different geological units were investigated from the landslide inventory map. In addition, the mechanism of landslide beginning in geological units was studied. Total yearly and monsoon rainfall amounts, the geographical distribution of rainfall, and the distance to the drainage map were used as hydrological characteristics. Data from seven stations from 2010 to 2021 were used to create the rainfall distribution map. The slope, aspect, curvature, topographical wetness index, and “T” factors were used for topographical characterization. The shear behavior, phase relation, and index properties of 120 landslide soils were obtained for geotechnical characterization. A size, activity, and mechanism-based classification of the landslide were proposed. For the susceptibility analysis, 14 landslide-causing factors were chosen. Similarly, four bivariate models were used for landslide susceptibility analysis: the weight of evidence, frequency ratio, information value technique, and Shannon's entropy. The silt/clay ratio in Siwalik's soil is one of the leading causes of landslides in saturated conditions. The soils of the Middle Siwalik are stiff, whereas those of the Lower and Upper Siwalik are soft. Lower and Upper Siwalik soils are similarly poorly graded. The average shear strength in the Lower and Upper Siwalik is also lower than in the Middle Siwalik. Minor and shallow landslides characterize the Lower and Upper Siwalik. Large-scale landslides are prevalent in the Middle Siwalik. The "T" factor and landslides have a positive association. There is a substantial positive relationship between total annual rainfall and yearly landslides. Similarly, hill slope and landslide incidents are strongly correlated. A size-based classification was created based on the landslide area's logarithmic scale. Size-based classification is proposed in five sizes: very small, small, medium, large, and very large. Landslides with less than 100 m2 of surface area are considered very small, while those with more than 100,000 m2 are considered very large. For activity-based classification, five activity states are recommended: new, active, inactive, stable, and reactivated. It describes the intended activity state conditions. Based on the landslide mechanism, five types of landslides have been proposed: Type 1, Type 2, Type 3, Type 4, and Type 5. The percentage of very high susceptibility (21%) is obtained from the information value method, whereas the low susceptibility percentage (8%) is obtained from the Shannon entropy model. Medium susceptibility is obtained higher from the information value, weight of evidence, and frequency ratio models. The result shows that the susceptibility distribution is more or less similar between frequency ratio, the weight of evidence, and the information value model; however, the Shannon entropy model has a slightly different result. The weight of the evidence model has a higher accuracy and prediction rate, according to the results. The WoE model has a success rate of 85% and a prediction rate of 79.9%. The accuracy and prediction rate of the remaining three models are comparable. The prediction rate hierarchy is WoE (79.9%), FR (75.3%), IVM (74.4%), and SE (73.2%). The success rates of four different models (WoE, FR, IVM, and SE) are 85%, 78.75%, 78.57%, and 77.2%, respectively. Every model's accuracy and prediction rate are greater than 70%, indicating that all models can be used to predict landslide susceptibility in Nepal's Siwalik Hills. हिमालय क्षेत्रमा पहिरो खस्नु एउटा निरन्तर भौगर्भिक प्रक्रिया हो । नेपालको सवहिमालय (सिवालिक) क्षेत्रमा वर्षायाममा ठूलो मात्रमा पहिरो जाने गरेको छ जसले गर्दा हरेक बर्ष मान्छेको जिउ धनको क्षति हुने गरेको छ । सक्रिय टेक्टोनिक्स, भूकम्पीय गतिविधि, मनसुनी वर्षा, कमजोर भौगर्भिक अबस्था र ठाडो भिर युक्त जमिनहरु हिमालय भूस्खलन र पहिरो जाने प्रक्रियाका महत्वपूर्ण अवयवहरु हुन् । यस अध्ययनले नेपालको पश्चिम क्षेत्रको सवहिमालय (सिवालिक) भित्र पर्ने बबई नदीको जलाधार क्षेत्रमा पहिरोको वर्गीकरण र संवेदनशीलता मोडलिङका साथै भौगर्भिक, जलविज्ञान, भूसतहिक र भूप्राविधिक विशेषताहरु प्रयोग गरी पहिरोको विशेषता निर्धारण गर्ने लक्ष्य राखेको छ । अध्ययनको सुरुवात पहिरोको सूची नक्साङ्कनबाट गरियो । जसमा गुगल अर्थ, ल्याण्ड स्याट र सेन्टिनल इमेजरीहरुको प्रयोगबाट इस्वी सम्बत २०१० देखि २०२१ सम्मका नयाँ तथा पुराना पहिरोहरुको स्पेश र टाइमका फरक नक्साहरु तयार गरियो । डिजिटल एलिभेसन मोडलको प्रयोगबाट पहिरो जाने सम्भावित फ्याक्टरहरुको नक्सा तयार गरियो । भौगर्भिक नक्सा तयार गरी तीनवटा फर्मेशनहरु क्रमश लोयर सिवालिक, मिडल सिवालिक र अपर सिवालिक साथै चट्टान नबनेका तटीय सेडिमेन्टहरुलाई quaternary deposit मा छुट्याइयो । अध्ययन क्षेत्रको पुरै भाग समेटिने गरी प्रत्येक फर्मेसनबाट १०,००० वर्ग मिटर भन्दा बढि क्षेत्रफल भएका ४० वटा पहिरोहरु छुट्याई स्थलगत अध्ययन गरी माटोको नमुना सङ्कलन गरियो । सङ्कलित नमुनाहरुलाई भूप्रयोगशालामा ल्याई विभिन्न भूप्राविधिक परीक्षणहरु गरियो । पहिरो संवेदनशील नक्साङ्कनका लागि १४ वटा सम्बन्धित कारकहरुको नक्सा तयार गरियो र पहिरो प्रकोपको अवस्था थाहा पाउन ४ वटा bivariate model हरु छनोट गरियो । यस अध्ययनको नतिजाबाट समग्र बार्षिक वर्षा र समग्र बार्षिक पहिरो सङ्ख्या बिच पर्याप्त सकारात्मक सम्बन्ध देखियो । पहाडको पन्ध्र डिग्रीदेखि पैंतालिस डिग्रीको स्लोप बढी संवेदनशील देखिन्छ । दक्षिण aspect मा बढी पहिरो जाने गरेको भेटियो भने concave सतह भएको भिरालो जमिनमा बढी सङ्ख्यामा पहिरो जाने गरेको पाइयो । माटोमा पाइने सिल्ट/क्ले अनुपात वर्षाको पानीले पहिरो गराउने प्रमुख कारण रहेको पाइयो । Lower र Upper सिवालिकका माटोहरु नरम र कम घनत्वका भेटिए भने Middle सिवालिकका माटोहरु कडा र बढी घनत्वका भेटिए । समग्रमा Middle सिवालिकमा औसत shear strength parameter बढी देखियो जसले गर्दा चट्टानी पहिरो बढी तर माटोको कारणले जाने पहिरो न्यून सङ्ख्यामा देखियो । पहिरो जाने सम्यन्त्रका आधारमा सिवालिक क्षेत्रका पहिरोहरुलाई पाँच समूहमा बर्गीकरण गरियो । त्यसैगरी आकार र गतिशीलताका आधारमा पनि पाँच समूहमा बर्गीकरण गरियो । अध्ययन क्षेत्रमा चारै ओटा मोडलका पहिरो संवेदनशील नक्साहरु तयार गरियो जसमा weight of evidence मोडलले frequency ratio, information value र entropy मोडल भन्दा उत्तम नतिजा दिएको छ भने चारैओटा मोडलहरु पहिरो जोखिम अध्ययनको लागी प्रयोग गर्न सकिने देखिएको छ । सबै मोडेलहरुले पहिरोको जोखिम बीस देखि तीस प्रतिशतको हाराहारीमा देखाएको छ । यो अध्ययनले नेपालको सिवालिक क्षेत्रको पहिरोको बहुआयामिक तवरले विशेषीकरण गरेको छ र उक्त क्षेत्रका पहिरो अध्ययन र अनुसन्धान तथा नियन्त्रणमा महत्वपूर्ण भूमिका खेल्न सक्ने छ ।
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    Water resource potential and socio-economic impact assessment of the proposed upper Karnali Hydroelectric project, Nepal
    (Department of Environmental Science, 2013) Jyakhwo, Rabindra
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    Assessment of water availability and river health in the Marshyangdi watershed, Nepal
    (Institute of Science and Technology, Environmental Science, 2022) Singh, Reeta
    Understanding water availability is essential for water resource development and management, as well as devising river health interventions. Climate change/variability impacts the hydrology of a river system which subsequently affects human and ecological health by altering the structure and function of the aquatic ecosystem. This study, therefore, aims to assess water availability and river health under current and future climate scenarios in the Marshyangdi Watershed, central Nepal, which has a huge potential for water infrastructure development. The specific objectives are i) to assess historical trends in the climatic variables, ii) to project future climate, iii) to evaluate the impacts of projected changes (climatic) on streamflow, and iv) to assess river health under current and future climatic conditions. Historical (1983-2013) and future (near-future: 2014-2033; mid-future: 2034-2053) trends in the climatic extremes were computed using RClimDex and hydrologic extremes using the Indicators of Hydrologic Alteration (IHA) tool. Bias-corrected projected future climate for the near and mid future under moderate (RCP 4.5) and pessimistic (RCP 8.5) scenarios was developed based on multiple regional climate models. Further, trends in extreme indices were estimated using the Mann-Kendall test and Sens’s slope estimator. A hydrological model was set up in the Soil and Water Assessment Tool (SWAT). It was calibrated and validated at multiple hydrological stations. Simulated hydrological time series was used to assess water availability under current and future conditions. Similarly, river health conditions under current, as well as future scenarios, were evaluated based on a customized indicator-based framework. The annual maximum temperature was observed with a significant increasing trend over the historical period at all the stations whereas temperature-related extremes showed both increasing and decreasing trends (e.g., warm spell duration index, warm days, and summer days are increasing whereas cold spell duration index, cool days, and warm nights are decreasing). Further, trends in precipitation extremes such as the number of heavy and very heavy precipitation days and maximum 1-day precipitation were decreasing along with the average annual precipitation amount in the entire watershed, indicating drier and hotter conditions over the historical period in the watershed. vi The climate in the Marshyangdi Watershed was projected to be hotter and wetter in the future. Among the stations, maximum climatic variation was observed at the Chame Station (Index: 816), with average annual precipitation projected to increase by 10% under RCP8.5 for mid-future, and maximum temperature increase at the rate of 0.06 o C/year. Maximum temperature and temperature-related extreme indices (hot nights and warm days) have been projected to have an increasing trend for both scenarios. Similarly, average annual precipitation has been also projected to increase at all the stations in the future for both RCPs but further decreases in consecutive dry days at most stations indicate wetter conditions in the future. Climate change is anticipated to increase hydrological alterations from low (in the current) to high (in the future) as revealed by the IHA tool. Annual average water availability increased, varying across seasons, and seasonal trends followed the annual trends. The average annual volume of water in the Marshyangdi Watershed was estimated to be 9,335 Million Cubic Meters (MCM), which will increase by 15% in the near future and 11% in the mid-future under RCP8.5 scenarios. Statistically, at a 5% level of significance, current river health showed moderate condition (67% of the sites) and it is projected to remain the same condition in the future, for both near and midfuture under both RCPs (4.5 and 8.5) scenarios but with varying degrees. Keywords: Climate Change, Indicators of Hydrologic Alteration, Marshyangdi Watershed, River Health, SWAT
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    Emission inventory of Nepal's air pollutants for effective air quality management
    (Faculty of Environment Science, 2022) Das, Bhupendra
    Air pollution is a serious issue in Nepal. It has an impact on the environment as well as human health. This study covers three main sectors of air pollution: crop residue open burning (CROB), open burning of municipal solid waste (MSW), and emissions from diesel vehicles. To estimate specific pollutants from various sources, an inventory of emissions factors (EFs) is required. This study presents a gridded emissions inventory of Nepal's key open burning sectors at a fine resolution of 1 km x 1 km. In 2016/17, the mass of CROB was 2,908 Gg, accounting for 22% of the dry matter produced. The air pollutant emissions were calculated by multiplying the mass of crop residue burned with EFs, which was CO 2 4,140, CO 154, CH 4 6.5, SO 2 1.2, PM 2.5 24.5, OC 8.6, BC 2.2, NO x 7, NMVOC 22.5, and NH 3 2.7 , in Gg/yr. Open burning was more common in districts with less cattle per hectare. The other contributing factors were the use of combine harvesters, especially in the Tarai districts, and labor migration. Rearing more cattle and utilizing dung for clean energy production as well as industrial raw materials could be the mitigation options to reduce CROB. Likewise, the entire quantity of garbage burnt openly in 2011 was estimated to be 89.2 Gg (i.e., 0.24 Gg/day), accounting for 4.5% of all waste generation. By multiplying the mass of waste burnt with EFs, the air pollutant emissions were estimated as PM 2.5 0.67 (OC 0.51), PM 10 0.72, BC 0.3, CO 2 145, CH 4 0.36, SO 2 0.06, NO x 0.23, CO 7.66, NMVOC 1.36, and NH 3 0.07, all in Gg. Lower waste collection efficiency reveals more open burning, especially in the rural areas of Kathmandu Valley and Nepal. MSW open burning could be minimized with proper waste collection services as well as recycling practices. The emission inventory of diesel vehicle categories was obtained through experimentallybased EFs for the Kathmandu Valley and Nepal. The fuel-based EFs of CO 2 , CO, BC, and PM 2.5 were calculated using the carbon mass balance technique. In average, the EFs of the diesel vehicles measured while idling (n = 29) were 2,600 for CO 2 , 33.3 for CO, 0.6 for BC, and 5.2 for PM 2.5 , in unit of g/L. In average, the EFs of the diesel vehicles measured while moving (n = 5) were 2,476 for CO 2 , 97.3 for CO, 1.7 for BC, and 20.7 for PM 2.5 , in g/L. In 2017/18, CO 2 was estimated as 2,214-2,781, CO 27.7-88.8, BC 0.513.55 and PM 2.5 3.42-23.47, in Gg, of which 24.4-29.5%, 28.9-32.3%, 12.3-31.9%, and 21.8-42.5% was respectively for the Kathmandu Valley. Higher emission were from lower euro-grade vehicles, including lack of proper maintenance in time, low fuel quality, traffic congestion, and roadway-grade. Implementation of higher grade vehicles (> Euro III/BS III), electric vehicles, better fuel quality with low sulfur, timely repair and maintenance of vehicles, road repair and opting for low-carbon sustainable pathways could significantly reduce air pollution from the transport sector. This study recommends sound policies for open burning and transport sectors that would significantly improve air quality as well as assist in minimizing negative health effects in Nepal.
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    Climate Trend and Treeline Dynamics in Nepal Himalaya
    (Faculty of Environmental Science, 2016) Gaire, Narayan Prasad
    Representing each site and species, six ring-width site chronologies dating back up to AD 1763 were developed from A. spectabilis and B. utilis. Response function analysis revealed that, depending upon the study sites, the radial growth of A. spectabilis was limited by temperature and or moisture stress. In SNP region it was more sensitive with summer temperature, while in MCA and RNP region, the growth was more sensitive with spring season temperature and moisture. The radial growth of B. utilis was limited mainly due to the moisture stress during spring season with positive relation with precipitation and negative relation with the temperature of the same season; however, in some sites it was due to insufficient temperature during growing period. The March–June average temperature and total precipitation of western Nepal was reconstructed for past over 170 years (1840-2013 AD), which showed non-significant long-term trend. The temperature reconstruction identified several periods of warming and cooling. The short cold episodes were observed around 1880s, and 1910s, while warm episodes were centered in 1870s, 1890s, and 1980s. Similarly, the reconstructed precipitation showed several wet and dry periods. The correlation between the reconstructed spring temperatures with indexes of sea surface temperature of the equatorial Pacific and extended multivariate ENSO Index revealed a significant negative correlation with monsoon and post monsoons seasons. The relationship with precipitation was in opposite direction than that with temperature. This relationship demonstrates that the climate of western Nepal has spatio-temporal linkages with global scale climatic variability. However, both the observed and reconstructed temperature from MCA region has weak relation with global climatic phenomenon suggesting some local effect in climatic condition. The different regeneration and migration pattern of studied species indicated that the treelines in Nepal Himalaya were also subject to changes in species composition. Population demography and growth response studies suggested that trees in Nepal Himalaya have a species-specific and site dependent response to climate change. Further studies at treeline ecotone incorporating climatic and non-climatic, biotic and abiotic factors will enhance our understanding on treeline dynamics in Nepal Himalaya in response to the rapid environmental change including climate change.
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    Population and Ecology of Sarus Crane (Grus antigone, Linnaeus 1758) in Northern Region of Rupandehi District
    (Faculty of Environmental Science, 2015) Gyawali, Bigya
    The present study was carried out on Sarus Crane (Grus antigone antigone) to estimate population of Sarus crane in the Northern region of Rupandehi district, to know breeding success and nest ecology of Sarus in the study area. This survey was carried out in August to October, 2013.Village road was taken as transect. Field observation and informal discussion was conducted to assess population status to know breeding success and assess nest ecology. Nests were visited and measured with a tape without disturbing eggs. Survey was carried out in 18 VDCs. 95 individuals of Sarus crane were found among which 29 were breeding pairs, 11 were observed in flock and 3 as single individuals and 23 were juveniles. Mean encounter rate of the Sarus was about 9 individuals per 7 sq. km. The maximum flock size was 11 individuals. Hatching success rate was 63.88 chicks per 100 laid eggs and 127.77 individuals per 100 nests. Among the active nests monitored, at least one egg was found in 18 out of 19 nests. So nesting success was 94.73 %. Among the 19 nests, 42.10 % were observed in wetland and 5.26 % in agricultural land and 52.6 % were in the interface of wetland and agricultural land. Average area of nest was 2.76 m 2 (n=19).
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    Assessment of Parabolic Solar Cooker as Alternative Cooking Fuel and Users’ Perception towards it in Beldangi Refugee Camp, Damak
    (Faculty of Environmental Science, 2016) Nepal, Khyam Raj
    This study was carried out to assess the effectiveness of Solar Cooker (SK-14) in Beldangi Refugee camp, Damak, Nepal and its contribution towards the sustainability. A questionnaire survey in user’s household was conducted to assess the user’s attitudes and field sample survey was conducted for the assessment of the saved amount of biomass and fuel related CO2emission compare to baseline cooking technology. Solar cooker has been used for cooking purpose along with solid biomass as briquette coal and fuel wood. According to the survey data the average numbers of hours using solar cooker is about 4 hour (3.95) per day,663 hrs in a year as average number of days using solar cooker is 46 days in per 100 days. Among these facts 74 % of respondent’s family uses daily, 22% respondent’s family uses occasionally and rest 4% are not using due to partial damage or lack of space. The user’s expressed their satisfactions regarding the operation of SK-14, found to have 11% excellent, 55% goods, 17% satisfactory, 11% poor and 6% very poor performance. The amount of heat energy contributed by the SK- 14 throughout the year is 1068.1 MJ for the cooking (average 663 hrs as effective operating hours in a year) with average power of 430watt. Again the amount of CO2 emission reduction by one solar cooker in one year is found to be 3.906 tons if baseline cooking technology is traditional cook, which is equivalent to 1065.95 kg of fuelwood. Similarly, the amount of CO2 emission reduction when improved cook stove is found to be 1.953 tons per year per solar cooker and this is equivalent to 532.75kg of fuel wood.
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    Habitat Preferences and Illegal Trade of Chinese Pangolin Manis pentadactyla (Linnaeus 1758) in Kavrepalanchowk District, Nepal
    (Faculty of Environmental Science, 2015) K.C., Anju
    Available with full text
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    Ethnobotanical Study of Muchu Vdc in Humla District
    (Faculty of Environmental Science, 2012) Prajapati, Meena
    Humla is one of the remote mountainous districts situated in the northwest corner of Nepal bordering with China. The main objective of research is to assess the ethnobotanical study of Muchu VDC and to know the similarity of ethnobotanical and conservation knowledge of different age people. Research was carried out in 9 wards of Muchu VDC Humla. Data collection with other required information was collected on June 2010. Semi structured questionnaire was conducted randomly in Muchu VDC. Likewise, the questionnaire survey was supplemented with the interviews, group discussions, different informal interaction, and direct field observation. The data of consensus analysis were analyzed through PAST software. This study documented the traditional ethnobotanical knowledge of Lama Community of upper Humla. The study could identified and documented 148 species of plants, out of which 17% are cultivated in the fields, 72% are available in nearby forest and lekh and remaining 11 % are found both in wild and cultivated form. Among them maximum 71% of plants are herbs and least 1% of them are Creeper. In lama community there have a wide range of knowledge on the use of plants for various purposes here 69% plants are reported to be of single use, 23% with double use and 8% with triple use. Especially old age people have very good knowledge of plant species and their uses. This is one of the best technologies in such remote area where there are no facilities of healthcare center. However, the consensus analysis shows no agreement of ethnobotanical and conservation knowledge of different age people. It is possibly due to the attraction of new generation towards allopathic medicine, commercialization of medicinal herbs and influences of modernization cause the traditional ethnobotanical knowledge diminishing slowly. Therefore, the traditional ethnobotanical knowledge should be preserved, promoted and disseminated. Keywords: Ethnobotanical knowledge, Medicinal plants, Traditional medicine, Humla, Consensus analysis
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    Study of Vegetation Ecology, Conservation and Management Practices of Betini Community Forest in Mangalbare Urlabari of Morang District, East Nepal
    (Department of Environmental Science, 2012) Ghimire, Nirmala
    A study on vegetation ecology, conservation and management practice of Betini Community Forest (BCF) was conducted in Urlabari Village Development Committee (VDC) of Morang district of Eastern Nepal. The field work was conducted on the month of January to March in 2011. The major objectives of this research were to study the species diversity of the forest and its status, demand and sustainable supply of the forest product, to identify the management practice of the community forest (CF) and to analyze the socioeconomic aspect of the Community Forest User Groups (CFUGs). The methodologies include both primary and secondary data collection. The primary data were collected by vegetation survey, socioeconomic survey, Focus Group Discussion (FGD), Key Informant Interview (KI) and Interaction with management committee. The secondary data were collected through the internet, report, and other related journals. Vegetation survey was conducted by using random sampling method in 49 quadrates where as socio economic survey was conducted using structured questionnaires of 79 HH through stratified random sampling method. The density and diversity index of the forest indicates that the forest was dense (higher diversity) with dominant species of Shorea robusta and the forest was more evenly distributed. The forest was found to be good in terms of high regenerating species. However the demand of forest product does not match with the supply from CF. Resources demand was found to be two times more in fuelwood and 35 th times more in fodder than the forest can supply. Large farm households (HH) have fulfilled the deficit of fodder and fuelwood through their own land and have adopted alternative energy resources like biogas. The landless and small farm HH had high pressure on the CF regarding the fuelwood and fodder. The unequal resource distribution compels the locals for illegal extraction of resource from the CF. The forest management practice of the CF was found to be weeding, thinning and new plantation which is entirely depends on their traditional knowledge. Also the forest provided good habitat for the different kind of animals, birds, and maintain biological corridor of elephant. Key Words: Community Forest, Forest User Groups, Demand, Sustainable supply, Species Diversity, Biodiversity Conservation, Biological Corridor
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    Climate Extremes and Landslide Hazard Mapping of Puwa Watershed, Ilam
    (Department of Environmental Science, 2011) Bhattarai, Mahendra
    Available With Full Text
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    Role of Biogas for Emission Reduction of Greenhouse Gases, A Study from Damak Municipality of Jhapa District
    (Department of Environmental Science, 2012) Adhikari, Bimala
    Burning of fossil fuel and extensive use of fuel wood are the major sources of green house gas emission in Nepal. It can be reduced by the use of biogas. The field work was conducted on January and February of 2010. This thesis work tends to calculate the emission reduction of greenhouse gases by the use of biogas at Damak municipality of Jhapa district. The study estimates the benefits of using biogas over the traditional use of fuel wood. Both primary and secondary data collection and analysis were done. Primary data were collected through questionnaire survey, focus group discussion; key informants interview and field visit whereas the secondary data were gathered from the review of related literature, publication from various organizations and related websites. There was a considerable reduction in the consumption of fuelwood at the surveyed households after the installation of the biogas plant. Reduction in fuelwood consumption consequently reduces the emission of greenhouse gases. There was a reduction of 7.99 tons of carbondioxide equivalent per households per year due to reduction in consumption of fuelwood. There was reduction in 0.0022 tons of Carbondioxide equivalent per households per year due to less consumption of LPG. But there was no reduction in the consumption of the kerosene at the study area after the installation of the biogas plant. There was an annual saving of NRs. 21210.55 due to reduction in consumption of fuelwood and LPG at the study area. The payback period for the biogas plant that gets subsidy and economic incentives from community forest and those which do not get any subsidy are 1.58 years and 2.16 years respectively. Key words: Biogas Plant, Emission reduction, Greenhouse Gases, Payback Period
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    Impact of Bhutanese Refugee Settlement on Humse-Dumse Community Forest: A Case from Beldangi, Damak, Jhapa, Nepal
    (Department of Environmental Science, 2012) Subedi, Sandhya
    United Nations High Commissioner for Refugees defines four main reasons for refugees flows: political instability, economic tensions, ethnic conflict, and environmental degradation. Movement of thousands of people and the establishment of refugee camps often has a serious impact on local environment, as well as on the welfare of nearby communities. Nepal has also hosted Bhutanese refugees in the eastern region since 1990. In this context, Humse-Dumse Community Forest was selected to study the impacts of Bhutanese refugee settlements on the forest, as three refugee camps (Beldangi I, Beldangi II and Beldangi III) have been established inside the forest. The reconnaisance survey was conducted during October 2010 and field survey during January 2011. Vegetation analysis and questionnaire survey (to both refugees and Community Forest User Groups) were done by using stratified random samplings. Socio-economic status of the Bhutanese refugees and CFUGs, their resources (fodder and fuelwood) need and access, and their extraction practices are highlighted in the questionnaire survey, and status of forest resources and its supply scenario are highlighted in the vegetation part. The camp settlement inside the CF has reduced the forest area by one fifth. As the refugees had no strong income source, they had no other better alternative (for the fuel resource) than extracting fuelwood from the nearby village, Community Forest and from market. From the CFUGs, landless were more depended on the C.F for both fodder and fuelwood. Annual extraction of both fodder (2896.07 t/yr) and fuelwood (1503.74 t/yr) by the Bhutanese refugees are quite higher than that of CFUGs‟ (fodder; 1792.53 t/yr and fuelwood; 289.16 t/yr), outstripping the forest‟s annual sustainable supply (fodder; 152.83 TDN in t/yr and fuelwood; 1087.79 t/yr). Absence of refugee settlement would greatly reduce these extractions so that the C.F resources do not get overharvested. Moreover, the refugees‟ illegal activities such as slice cutting of trees stems, uprooting of regenerating species and small herb saplings, collecting twigs and broken branches for fuelwood, collecting fodder for their livestock were increasing pressure load for the forest resources. All these activities of the refugees in longer term will definitely decline the forest‟s sustainability to a very high extent. Therefore, there is an emerging need of strong policy amendment regarding these settlements inside the community forest. Key words: Bhutanese refugees, CFUGs, extraction, forest resources, sustainability, vegetation analysis, UNHCR.
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    Wetland Conservation through Water Quality Assessment and Willingness to Pay (A Case of Baral Danda Lake Complex, Kaski, Nepal)
    (Department of Environmental Science, 2012) Shahi, Anima
    The wetlands located at the periphery of Baral Danda Lake Complex (BDLC), Kaski, Nepal serves plethora of ecological and socio-economic benefits, yet they are subject to increasing natural and anthropogenic disturbances. This study aims in finding situation of wetlands conservation based upon the assessment of water quality index (WQI) of Bach (1980) in three lakes: Gunde, Neureni and Khaste of Lekhnath municipality. The study was carried out for two seasons; dry and rainy from March, 2010 A.D. to July, 2011 A.D. The socioeconomic analysis was done using contingent valuation method (CVM) for estimating willingness to pay (WTP) in lake conservation. The lakes were found to be critical pollution (II-III) during dry season and severe pollution (III) during rest of the study period for Gunde and Neureni lakes. While Khaste lake accounted to be severe pollution throughout the study period. The indicator tolerant species of organic pollution recorded in three lakes also supported the results of WQI. Significant differences in Dissolved Oxygen (DO), Electrical Conductivity (EC), Free Carbon Dioxide (CO 2 ), Biochemical Oxygen Demand (BOD iv 5 ), Chemical Oxygen Demand (COD), Orthophosphate (O-PO 4 2- -P) and Total Iron were observed for annual and seasonal data. Whereas, no significant differences were found in pH, temperature, total alkalinity as CaCO 3 , total hardness as CaCO 3 , chloride, ammonia and nitrate in comparison with WHO values and Nepal Drinking Water Guidelines. The lakes were not suitable for recreation purpose due to dense growth of algae and macrophytes. Neureni lake could be suitable for aquaculture than other two lakes and Khaste lake; suitable for irrigation water. All lakes water could be suitable for livestock watering. Likewise, about 81.60% of respondents emphasized in lakes degradation with time and appealed for conservation. From WTP calculation, it was computed that aggregate WTP per annum to be around NRs. 391, 200 (US$ 4,400). This suggested the individual household WTP per annum to be NRs. 397.56 (US$ 4.47) i.e. NRs. 33/month/household. The maximum amount of WTP by respondents was negatively correlated with age of the respondents, time duration of living in the village and total number of family members. Degrading lake water quality and local people‗s strong willingness in lake conservation thus signified the need of wetlands conservation in BDLC. Keywords: Water Quality Index, Wetland Conservation, Willingness to Pay
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    Feasibility Analysis of REDD+A Case Study in Ghwangkhola Sapaude Babiyabhir Community Forest of Syangja, Nepal
    (Department of Environmental Science, 2012) K.C., Anup
    Climate Change is growing as a hot issue throughout the world. It is necessary to apply mitigation and adaptation strategy for combating climate change.Reducing emissions from deforestation and forest degradation (REDD) is potentially low-cost option for mitigating climate change.The main objective of this study was to determine the carbon stock and cost-benefit analysis(CBA)of community forest (CF)by entering into carbon trading through REDD. For this, the study was carried out in Ghwangkhola Sapaude Babiyabhir CF(GSBCF), Syangja.The CF was established in 2000 with an area of 92 hectares with 195 Community Forest User Group (CFUG)members.The total carbon stocks of forest in 2011 was measured by following the guidelines prepared by MFSC and jointly by ICIMOD,ANSAB and FECOFUN. Information about the socioeconomic condition of the CFUG and cost and benefit associated with Community Forest Management (CFM)was collected fromCF Operation Plan, focus group discussion (FGD), key informant survey (KIS) and household (HH) survey. Population of female was more than that of male among the CFUG. More than 52% of total CFUGs had medium economic standard in the village. On an average,11.61 ropani of land was owned by each household in the village.Average total livestock per household in this CFUG was 5.62. The forest was with Cast on opsis-Scimalying at an altitude range of 970 to 1320 masl. More than 90% of the trees in the forest had diameter less than 20 cm which had high potential of increasing biomass in the future.The biomass in the forest was 164 ton/ha,with yearly incre men to f 0.95 ton/ha. The total carbon stock of the forest was 122.29 ton/ha, including soil organic carbon and below ground carbo no f 45.18 ton/ha and 12.85 ton/ha,respectively.The total Opportunity Cost of the forest was US $ 329.Rich, medium and poor HH were willing to pay 25.97 %, 51.95 %, 22.08 %of Total Willingness to Pay(WTP) respectively for the ecological services provided by the forest.The annual total benefit and cost in 2010 was US $ 7300 and 2456, respectively.Benefit Cost Ratio measured directly with out discounting and with discounting for 10 years from 2006 to 2015 was 2.97 and 3.91, respectively.The study concludes that the CF had already benefitted from current state of management. If REDD scheme is introduced in the community forest of Nepal, it will provide additional benefit of carbon credit to the CFUG. Keywords: GSBCF,Carbon sequestration, REDD, WTP, Opportunity cost, CBA.
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    Climate Change and Its Impact on Agriculture Productivity of Nuwakot District
    (Department of Environmental Science, 2012) Subedi, Sangita
    Agriculture is very much sensitive towards climatic variability. Changes in climatic factors like temperature, solar radiation and precipitation have potentials to influence crop production. Nepalese economy depends largely on agriculture which contributes 42% of the total GDP. In this regard an attempt has been made to investigate the effect of climatic variability on the paddy, wheat and maize yield in plant ationmaturity and harvest period in Nuwakot district. The climate variables analyzed in this study are temperature,and rainfall. These two variables are used to explore the relation of climate to the paddy, wheat and maize yield based on 20 years of data records from 1990 to 2009. The regression analysis was carried out to study the climatic trend also the correlation analysis is carried out between the backward difference filtered climatic parameters and the backward difference filtered cropyield. Over the last 20 years the mean temperature increased by 0.051 VII 0 C per year.Therehas been 0.06 0 C per annum increase in maximum temperature and 0.006 C perannum increase in minimum temperature.. The warmest year was 2009 with the mean maximum temperature of 29.19 0 C.Regarding the rainfall, total mean annual rainfall was of 1922.7 mm with mean annual rainfall of 155.72 mm in the district.The year 2002 remained the wettest year with total mean annual rainfall of 2285.6 mm and the year 2006 was the driest year over the study period with total annual rainfall of 1254.4 mm. The present study concludes that increase in temperature and increase in rainfall is favorable condition for paddy yield .In case of wheat increase in temperature and rainfall is favorable in plantation period only,the condition is reverse in maturity and harvest period. However in case of maize decrease in temperature and increase in rainfall is favorable for both plantation and harvest period.The impact of irrigation in crop yield has not been considered in this study.Furthermore, the complex relationship between crop and climate should be studied in detail taking into account of the multiple relations between various meteorological variables.
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    Impact of Climate Change on Agricultural Production: Case of Kavre and Jumla District
    (Department of Environment Science, 2012) Pandey, Keerti Singh
    Nepalese economy depends heavily on agriculture. Agricultural sector alone contributes about 42% of the total GDP. Climate change is a global phenomenon which has affected crop and livestock production practices and their yields. Negative effects are projected to be more prominent than the positive effects. In a humid climate like that of Nepal, there will be changes in spatial and temporal distribution of temperature and precipitation due to climate change, which in turn will increase both the intensity and frequency of extern events like droughts and floods. In this regard, an attempt has been made to investigate the effect of climate variability on the rice, wheat and maize yield in transplant/planting, maturity and harvest periods along Kavre and Jumla district of Nepal. The climate variables such as temperature, rainfall are utilized to explore the relation of climate to the crops yield based on 20 years of data records. The study focuses on the variability of rainfall and temperature in Kavre and Jumla districtin various cropping periods of rice, wheat and maize yield. The (linear) regression analysis is carried out to study the climatic trend. The correlation analysis is carried out between the backward difference filtered climatic parameters and the backward difference filtered crops yield. There has been 0.02 0 C per annum increase in temperature of Kavre district and 0.064 C per annum of Jumla district. The average annual rainfall of the Kavre has been 1144.9mm and 797.8mm of Jumla district. The impact is assessed for each cropping periods of respective crop. Yield of rice, wheat and maize is in growing trend, but fluctuates over the years. The correlation between rice yield and temperature and rice yield and rainfall in harvest period is negative at Kavre district but positive at Jumla district which shows positive response of climate change. Similarly, the correlation wheat yield and rainfall and minimum temperature in harvest period is positive whereas wheat yield and maximum temperature is negative at Kavre district. The correlation between wheat yield and rainfall and maximum temperature is positive but yield and minimum is negative at Jumla district. Likewise, the correlation between maize yield and temperature is positive but yield and rainfall is negative at Kavre district. While that of correlation between maize yield and rainfall and temperature is negative at Jumla district which shows climatic condition is favorable for maize production. The result has shown that extreme fluctuation in weather has caused negative impact on production in Jumla than that of Kavre district.