Geographical Journal of Nepal

Approach to multi-disaster risk assessment and policy recommendation for disaster resilient urban development: A study of Birgunj–Simara Corridor

2023-03-23T04:29:10+00:00

This study identified multiple nature of disasters in Tarai in general and Birgunj - Simara Urban Corridor, one of the hotspots of urbanization in Nepal in particular. Using geospatial technology, secondary sources of information, and stakeholder’s consultations, this study evaluated floods, earthquakes, windstorms, and fire impacts, identified factors contributing to vulnerability, and solutions for increasing resilience. Although rivers have limited floodplains, floods have been increased because of floodplain encroachment, improper drainage, land use changes in upper catchment, and climate change. Although the earthquake could have a high impact, the seismicity is low compared to the national context. During pre- and monsoon seasons, windstorms have a high impact over a limited area and are hard to predict. Fires are not widespread in the settlements but common during hot, dry months due to compact rural settlements, nonresilient house designs, and inadequate safety measures. Besides, lack of adaptation capacity as a result of poor awareness, widespread poverty, and poor disaster response have contributed to a high vulnerability to multihazards. Mitigation actions identified include risk-sensitive land use planning, flood control and hydraulic structure design, efficient urban drainage, waste management, resilient housing, and disaster safety plans. Local communities should be involved in developing early warning systems, disaster preparedness, and response measures.

GIS based Approach for Suitability Analysis of Residential Land Use

2023-03-23T06:48:08+00:00

Developing countries in particular are experiencing a tremendous rise in urbanization. Population growth and internal migration generated rapid urbanization and uncontrolled infrastructure construction in urban and semi urban area in Nepal. In general, local needs for infrastructure development, and construction of housing and apartments are typically used to select the most suitable site for residential use. Identification of the criterion is crucial to a suitability analysis based on local needs. Site suitability analysis is used for identification of the best location or site for residential area using geographic information system (GIS) based on multi-criteria evaluation (MCE). Majority of research work, spatial analytical hierarchy process (AHP) is a suitable tool and used in suitability analysis purpose. The criteria were determined through prior work and customized in the local situation interaction with land use planner as expert perspective and focus group discussions, and utilized in land suitability analysis. In this study, GIS-MCE-AHP models is applied as an effective approach of spatial decision making process and play efficient vital role for identifying the potential areas for residential use. In the suitability residential index map, suitable level of residential area is covered only 5% and 38% land covered with the moderate suitable for residential area in Sambhunath municipality. The suitable for residential area is mainly occurred along the major road network and surrounding to the existing settlement area. GIS conjunction with MCE and AHP is useful for conducting land suitability analysis and serving as planning tool for suitable residential site.

Greenwood regeneration status in community forests of Chiti Lamjung Nepal

2023-03-23T07:01:25+00:00

Forest regeneration is the process by which new tree seedlings become entrenched after forest trees have been harvested or destroyed by fire, insects, or diseases. The process is key to sustainable forestry and can be accomplished through natural regeneration, which occurs when new seedlings or sprouts are produced by trees left on or near the site. The study is to calculate the regeneration status of the tree species in community-managed forests. The sampling points were generated by using the random table. The sample quadrate size was taken 20m×20m for a tree, 5m×5m for a sapling, and 1m×1m for the seedling. In five community forests, altogether 30 quadrates were taken for a tree, 60 nested quadrates were taken for a sapling and 120 nested quadrates were taken for a seedling. The tree layer, sapling layer and seedling layer were differentiated by taking reference tothe Diameter at Breast Height (DBH) class. An individual having DBH ≥ 5cm is considered a tree, an individual having DBH value between 1cm to < 5cm is considered a sapling, and individuals having 1cm to < 5cm DBH are considered as a seedling. The DBH distribution curve was obtained by plotting diameter class in x- axis and density on y- axis. All studied community forests are mixed forest dominated by tree species Castanopsis indica, Diospyros embryopteris (Diospyros malabarica), Shorea robusta, and Schima wallichii (Schima wallichii choisy). The regeneration potential of the Tilahar community forest(CF) is found high despite high grazing and other human intervention. The DBH class distribution curve of tree species is found as inverse J-shape, indicating that the overall forest has a sustainable regeneration.

Landslide susceptibility analysis using frequency ratio and weight of evidence approaches along the Lakhandehi Khola watershed in the Sarlahi District, southern Nepal

2023-03-23T07:11:13+00:00

Landslide susceptibility maps are considered as one of the most important keys to limiting and dodging potential landslide consequences worldwide. In the present study, landslide susceptibility maps are prepared using bivariate models: frequency ratio and weight of evidence approaches. At first, randomly selected 80% of landslides i.e.,one hundred eighty landslides are used as training data for the preparation of the model, and the rest 20% of landslides i.e.,forty-five landslides for its validation. Similarly,thematic layers of nine causative factors of landslides such as slope, aspect, curvature, stream density, TWI(Topographic Wetness Index), land use, geology, distance from river and distance from the road have been analyzed for the modeling in ArcGIS. Finally, prepared landslide susceptibility maps are classified into five classes from Very Low to Very High from both methods. The area of Low, Moderate, High, and Very High susceptible classes is also nearly equal. The success rate curve of FR (Frequency Ratio), and WOE (Weight of the Evidence), show accuracy of 71.09%, and 75.62% respectively. Likewise, the prediction rate curve shows 72.87% and 76.66% accuracy on FR and WOE methods respectively. Since the susceptibility maps prepared through both approaches show an accuracy of >70%, the result is deliberated as fair. These maps are useful to all the stakeholders for land use planning and developing mitigation strategies against the consequences of increasing landslides in the Siwalik Hills of Nepal.

Plant communities and alien invasion in Kalika community forest, Kailai district, Sudurpashchim Province, Nepal

2023-03-23T07:20:47+00:00

One of the major threats to native biological diversity is caused by invasive alien plant species (IAPS). As the documentation of plant communities and alien plant invasion in Far-west Nepal is very scarce, this study was carried out in the Kalika community forest of Kailali district, Sudurpaschim Province, Nepal. The aim of the study was to identify plant communities and the status of IAPS in the forest. A total of 43 plots (size 10 m × 10 m) were sampled. Plant communities were distinguished based on the Sorenson similarity index and cluster dendrogram. Cover of the tree canopy and IAPS was measured. A total of 101 species of vascular plants were recorded from five types of plant communities in the forest. The communities were named as (i) Buchanania latifolia-Terminalia alata community (ii) Casearia glomerata-Mallotus philippensis community (iii) Shorea robusta-Terminalia alata community (iv) Adina cordifolia-Mallotus philippensis community (v) Terminalia-Shorea-Trewia mixed community. These communities were invaded by invasive Ageratum houstonianum, A. conyzoides, Bidens pilosa, Cassia tora, and Argemone mexicana. A high cover of IAPS was found in Terminalia-Shorea-Trewia mixed community. The cover of IAPS was low under the high tree canopy. Control and management of IAPS should be done to protect the native plant communities in the forest for reducing disturbance to maintain tree canopies. It is hoped to be an effective method to reduce alien plant invasions.

Use of plant extracts to control activities of the invasive giant African land snail Achatina fulica

2023-03-23T07:31:53+00:00

Giant African land snails (Achatina fulica; GALS) are a highly invasive herbivore and pose serious threats to native species and that could disrupt ecosystems. Various botanical extracts have been used as molluscicides to control mollusks for pest management. We aimed to identify the effects of neem (Azadirachta indica) and titepati (Artemisia vulgaris) to reduce GALS activities and survival using solutions of fresh neem leaf and titepati leaf, bark, and root. We found a fast movement in the GALS only in the extraction groups while the lethargic movement was lower in mulching method. A significant association of control groups with different extraction groups along with mulching treatment (p<0.05) however, no differences were observed among different extractions at 2.5% and 5% concentrations. Among the treatments, Neem leaf at 5% concentration was found to be effective as it helped immobilize the samples after ten days whilst other treatments required minimum 14 days to be effective. We recommend further studies of titepati and neem as control agents to reduce crop and vegetable damage from GALS.

Vegetation dynamics in the Madiwatershed, Gandaki Province of Nepal

2023-03-23T07:39:28+00:00

Monitoring of Spatio-temporal vegetation dynamic is one of the most important indicators used to track environmental quality. Spatial and temporal dynamics of Normalized Difference Vegetation Index (NDVI) values are the most useful and reliable technique to analyze the general vegetation dynamics at the regional level. Thus, this study analyzed the spatial pattern and temporal trend of NDVI values of naturally vegetated areas in the Madi Watershed of Nepal relating to its geomorphic and built-up density factors in 2000, 2010,and 2020. Lands at images were used to derive NDVI values and SRTM DEM and the topographic map were used to derive geomorphic factors and built-up density. This study excluded cultivated land, built-up area, water body, cliff, snow-cover area, glacier, and glacier moraine areas to derive only naturally vegetated areas. Human population data was collected from the population censuses. Field observation and information collected from the field to verify ground reality in 15 different watersheds. This study revealed that there is a significant increase in natural vegetation in all parts of the watershed. However, there is the highest rate of increase in vegetation in lower plain areas, where the population density is the highest. The overall increase in natural vegetation is because of the decreasing human and livestock population, changes in lifestyle, etc. The highest increase in natural vegetation in lower plain areas is because of the alternative use of cooking energy and building materials in urban and accessible areas, decreasing the number of livestock. Thus, it can be concluded that there is a significant impact of population dynamics on vegetation in the Madi Watershed of Nepal.

Difficulties Faced by Students and Teachers in Online Teaching Process During Covid-19 in Lalbandi Municipality

2023-03-23T07:45:51+00:00

This paper analyzes the difficulties faced by the students and teachers in online teaching learning process during the COVID-19 pandemic. Online learning is an alternative platform that replaced to the face-to-face mode of instruction. It refers to instruction that is delivered electronically through various multimedia, internet platforms and applications. This paper is based on mixed-method research design and primary and secondary data sources are used. Primary data were collected from field observation, personal interviews with students, teachers, parents, and focus group discussion. In this process, two secondary schools which were involved in online learning were purposively selected from Lalbandi Municipality of Sarlahi district of Madhesh Pardesh. Secondary data were collected from various sources- journals, Municipal offices, and e-resources. The findings show that online-learning has been felt more reliable mode of instruction during the pandemic situation for students, teachers and parents. However, it faces a lot of problems during operation and it became ineffective as compared to face-to-face mode of instruction. It is mainly due to the lack of electronic devices to support online class, lack of high-speed internet facility, irregular power supply, lack of teacher-students' interaction and ineffective assignment practices. As a result, a large number of students have not participated in online learning. Thus, this paper concludes that a strong institutional support policy among schools and local government requires to mainstreaming students participation in online-class.