South Sikkim Research Articles

Empirical Modeling of Soil Loss and Yield Utilizing RUSLE and SYI: A Geospatial Study in South Sikkim, Teesta Basin

Soil erosion and subsequent sedimentation pose significant challenges in the Sikkim Himalayas. In this study, we conducted an assessment of the impact of rainfall-induced soil erosion and sediment loss in South Sikkim, which falls within the Teesta Basin, employing Revised Universal Soil Loss Equation (RUSLE) and Sediment Yield Index (SYI) models. Leveraging mean annual precipitation data, a detailed soil map, geomorphological landforms, Digital Elevation Models (DEMs), and LANDSAT 8 OLI data were used to prepare the factorial maps of South Sikkim. The results of the RUSLE and SYI models revealed annual soil loss >200 t ha−1 yr−1, whereas mean values were estimated to be 93.42 t ha−1 yr−1 and 70.3 t ha−1 yr−1, respectively. Interestingly, both models displayed similar degrees of soil loss in corresponding regions under the various severity classes. Notably, low-severity erosion <50 t ha−1 yr−1 was predominantly observed in the valley sides in low-elevation zones, while areas with severe erosion rates >200 t ha−1 yr−1were concentrated in the upper reaches, characterized by steep slopes. These findings underscore the strong correlation between erosion rates and topography, which makes the region highly vulnerable to erosion. The prioritization of such regions and potential conservation methods need to be adopted to protect such precious natural resources in mountainous regions.

Swachh Bharat Mission (Gramin) and Practices of Solid Waste Management in Rural Sikkim

Generation of waste and disposal in rural areas has not been the prime focus for deliberation, unlike the urban areas where it is regarded as a crucial issue that demands immediate attention and solution. Until recently, managing solid waste was not considered an issue in rural areas of Sikkim. However, with the proliferation of solid waste in recent years due to increasing population, the growth of tourism industry and changing consumption patterns have prompted the government of Sikkim to decentralise the responsibility of managing solid waste in compliance with the guidelines of Swachh Bharat Mission (Gramin). Based on primary data collected from the two Gram Panchayats, namely Mellidara Paiyong and Lungchok Kamarey in South Sikkim district, the paper attempts to comprehend the various types of waste generated, and critically evaluate the common conventional methods and practices adopted by the villagers for disposal of their household waste. Simultaneously, it also attempts to assess various policies and strategies taken up by the local self-government in managing the solid waste generated from households.

Water Scarcity Zonation Mapping using MCDM Method in District, NAMCHI, South Sikkim using QGIS

Abstract: A major worldwide issue, water scarcity has especially serious repercussion like India that have an abundance of water. There are only so many fresh water sources available to meet the growing demand for water brought on by urbanisation, industrialisation, and population expansion, Since the limited water supplies cannot satisfy the population’s needs, a state of water scarcity has resulted. The present research is conducted in CCCT Chisopani, Sikkim, India. Water scarcity is a major issue in the area we selected, the multiple criteria decision making (MCDM) approach will be used in this case study to solve the ranking water scarcity problem, and the next upcoming major problem for water scarcity is the growing population in the study area. Along with the households the area consists of 2 study institutes due to which the population may increase in the coming years effecting the water management. The first step was to conduct a survey in and around the study area by preparing questionnaire including total population of household, highest qualification in the house, storage capacity, tenants, local source, rain water harvesting, hours water received, water fetched manually or not? Type of roofs, distance to perennial source. After collection, the data was evaluated and standardised to guarantee comparability across numerous criteria. Further the study was continued with water scarcity index calculation making it easier to prepare the zonation map for the study area. The MCDM method exhibits how the method can be used against the water scarcity problem. The main focus of the study was to create a scarcity map for the study zone in QGIS using RS&GIS method.

Unveiling Indigenous Traditional Knowledge (ITKs) Using Different Available Plants by the Local People of South Sikkim, India

Northeast India is biologically diverse regions, among which the South Sikkim district possesses unique rural landscapes enhanced with endless waves of farming areas and terraced hills. Within this region, three main indigenous groups—Nepali, Lepcha and Bhutia—coexist, contributing to the cultural diversity. Over the years, these communities have cultivated a traditional knowledge based on which they are greatly dependant on diverse plant resources for both protective measures and medicinal practices. These traditional practices encourages a strong local knowledge base. These practices include local plants namely utis (Alnus nepalensis), chilauni (Schima wallichii), wild fern, titepati (Artemisia vulgaris) and many more. However, despite the rich diversity of these cultural practices connected with nature, there is a lack of detailed exploration and documentation for better understanding traditional practices and ethno-medicinal knowledge upheld by these communities. The absence of such documentation underscores a significant gap in our understanding of their cultural heritage, as these ITKs can be further integrated with science to make contribution for adaptive management to many environmental and health issues. Therefore, this study is conducted with the aim to unreveal the potential of these traditional practices and ethno-medicinal knowledge preserve among the diverse communities of South Sikkim, which can help to shed light on their cultural heritage and to recognize their invaluable contributions.

An overview of Rodinia-Gondwana Supercontinents, India - Asia Collision, emergence of Himalaya and Paleobiogeography of the eastern Tethys in Indian Subcontinent, South Asia

The existence of Rodinia Supercontinent during Meso-Neoproterozoic and its subsequent breakup and reassembly as Gondwana Supercontinent is a widely accepted hypothesis in geological history of the Earth. The breakup of the Rodinia resulted in formation of rift basins and passive continental margins around 650 Ma. Major palaeoclimatic events like Neoproterozoic global glaciation (Snowball Earth) followed by global warming have been recorded from different continents including Indian Lesser Himalaya (Blaini -Krol Cryogenian-Ediacaran Period). The emergence of multicellular Ediacaran life in the Upper Krol Formation is consistent with an increase in the atmospheric oxygen. The base of Ediacaran System in the Lesser Himalaya is established in the cap carbonate, the Blaini Formation overlying the glacial diamictites (Blainian). The pink cap carbonate of the Blaini Formation shows negative δ13C value (-3‰ PDB) and invariably correlate with the Marinoan glacial event. Large continents of Gondwanaland Supercontinent South America, Africa, India, Australia and Antarctica were located over the South Polar region and global equatorial to polar oceanic circulation was blocked and may have been the main cause of glaciation. Paleogeographically Carboniferous–Permian diamictite, coal beds and plant fossil bearing Gondwana outcrops are found in South Sikkim and Arunachal Lesser Himalaya of Northeast India. The Late Paleocene – Middle EoceneTethyan foraminiferal – algal carbonate biofacies are well developed after Late Cretaceous – Paleogene mass extinction event in the eastern Tethys, Meghalaya, east India. These Tethyan benthic orthophragmine foraminiferal –algal limestones were deposited in the passive continental margin setting of a shallow marine carbonate shelf in eastern Tethys and Standard Benthic Zones (SBZ) of the Alpine- Adriatic western Tethys are recorded from Meghalaya. The Cretaceous – Tertiary boundary is well marked in these basins by biotic mass extinction. Late Cretaceous mega ammonoid fossils and Sauropod dinosaur bones are abundantly found in the Maastrichtian Mahadeo Formation. The present δ13C and δ18O isotope data is comparable with the marine values of the limestone The Umlatodoh Limestone contains foraminiferal taxa of early Ilerdian and Middle Eocene (early Lutetian) age. The Indo-Myanmar Orogenic Belt (IMOB) represents the eastern suture of Indian plate and it was formed due to the collision of the Indian plate with the Myanmar plate. The Naga-Manipur ophiolites have been assigned to range in age from Upper Cretaceous to Eocene on the basis of faunal assemblages (radiolarian, planktonic foraminefera) in the olistolithic blocks of pelagic limestone and cherts. Pan Indian Pre and Post India–Asia Collision, emergence of Himalaya and Paleogeography of the Indian Subcontinent has been discussed in South Asia.

Wind farm site suitability assessment & validation using geospatially explicit multi-criteria approach: A case study of South Sikkim, India

ABSTRACT Determination of optimal location for wind farm is a challenging task influenced by several decision criteria and factors subject to human. This case study done proposes an integrated decision support framework to investigate the spatial wind farm suitability based on F-AHP (Fuzzy-Analytical Hierarchy Process) together with Q-GIS (Quantum-Geographic Information System) tool. Firstly, spatial analysis and integration of nine-exclusion factors were included to identify the unsuitable sites. Next, F-AHP-based MCDM (Multi Criteria Decision Making) analysis was employed to obtain criteria weights of seven evaluation factors. Unlike traditional AHP method, the proposed F-AHP method is much flexible to deal with intermediate linguistic variable. F-AHP results reveal that wind speed is the most important criteria followed by power Tr. lines with weighted value of 33.05% and 20.95% respectively. The thematic suitability map was developed on Q-GIS platform to classify from “least suitable” to “most suitable” classes. The final suitable map indicates 26.09 km2 and 138.42 km2 area are most suitable and highly suitable respectively for wind farm establishment. This study is also supported with ground measurement wind resource data collected through a WMS (Weather Monitoring Station) installed at “most suitable” region of suitability indexed class.

Assessing the Socio-Economic Setup of Ravangla, Sikkim, and the Vulnerability of its Community using Geoinformatics

The geoinformatics platform integrates remotely sensed data and Geographic Information Systems (GIS). It has a vast range of applications. The technique is widely used not only to study the physical aspects of a region but also to analyse the social and economic setup. The objective of this study is to understand the socio-economic setup of Ravangla, which is a small tourist town located in South Sikkim, India. The primary data have been collected from the field survey and analysed using GIS tools. The social indices such as social structure, housing condition, and the condition of basic facilities such as health, education, transport, market, and others have been analysed in the present study. GIS has been used to study the spatial distribution of these social and economic parameters. The technique has also been used to assess the socio-economic vulnerability of the community living in Ravangla. The Composite Vulnerability at the community level has been calculated based on socioeconomic parameters and a vulnerability map has been prepared. Based on the Composite Vulnerability Index, the households in the study area have been classified as Highly, Moderately, and Less Vulnerable. The GIS techniques have been used to amalgamate the socioeconomic components of vulnerability to recognize the most vulnerable households in Ravangla. The study will help planners, policymakers, and administrators to take necessary steps for mitigating socio-economic problems in the study area.

Developing a model for residential water demand in the Indian Himalayan Region of Ravangla, South Sikkim, India

Climate change and increased demand for human needs have led to drinking water scarcity in the cities and towns located in the Indian Himalayan region. This paper aims to address the challenge of drinking water security by proposing a model of water demand among households in Ravangla town of South Sikkim, India. Our field survey results indicate that the water demand increases significantly due to the number of household members between the age of 18 and 60. Further, we find that the number of taps in the household is positively and significantly correlated with water demand. Number of water taps, storage capacity and the water consumption are positively related. However, we did not find any such strong association with the number of toilets in the household. The GIS maps of South Sikkim shows the areas with households that will soon face acute water stress and drinking water insecurity. In order to address the scarcity of water in these regions, policymakers may develop plans like rainwater harvesting to ameliorate the situation through a GIS based decision support system.

Response of water springs towards an earthquake: A case study from Sikkim Himalaya

Springs and streams are essential sources of fresh water for the Himalayan population. To global and regional extents, these resources are being severely affected by climate change as well as anthropogenic activities. However, the effects of seismicity also have considerable influence on springs but are negligibly studied in that aspect. Crustal deformation, shaking, and movement of the earth's surface due to an earthquake, can modify the stream flow and water level in wells through consolidation of surficial deposits and development of new fractures. The present study addresses the effect of an earthquake on water springs in a seismically active zone. On 18 September 2011, the Sikkim Himalaya experienced a strong earthquake of magnitude (Mw) 6.9. To assess the impact of this earthquake on hydrology, we studied the springs located in the South Sikkim district, India. Our research indicates that few springs dried up following the Mw 6.9 earthquake in 2011 while some springs discharged at a higher rate than before. The springs which were dried up due to climate change were excluded in this study. Furthermore, our study suggests that in tectonically active mountain ranges, like Himalaya, an earthquake not only causes surficial deformations but also influences the hydrological framework at a regional scale. Therefore, the seismic nature of the terrain should also be considered for spring rejuvenation policies.

Prevalence of Invasive Fall Army Worm Spodoptera Frugiperda (J E Smith) on Organic Maize in Sikkim

Fall army worm (FAW) Spodoptera frugiperda (J E Smith) has been observed invading the north eastern region of India during April 2019 in Mizoram and on maize crop of Namphing GPU, South Sikkim, during May 2019. The detailed survey in the maize growing areas of state revealed the presence of early to fourth instar larvae feeding on the leaves and whorls. The identification was confirmed by morphological characters and DNA barcoding with mtCO1. The study indicated range (8.8 to 71.4%) of FAW infestations on maize. During survey, microbial infection in few larvae, and predatory wasps and spiders as predators were found. This is the first record of FAW on organic maize of Sikkim.

Decadal trend analysis of rainfall patterns of past 115 years & its impact on Sikkim, India

Fluctuations or variations in climatic parameters is a recurring phenomenon in India. The effects of climate variability exacerbate existing social and economic encounters across the area. Over the last 115 years, the rainfall patterns in India have changed significantly. The most significant change is the shifting of the monsoon season altogether. This study aims to discuss the significant changes of rainfall pattern and their influence in Sikkim state, India. Daily rainfall data of 115 years from 1901 to 2015 has been processed in the study to find out the monthly variability of rainfall for which Mann-Kendall (MK) Test together with the Sen's Slope Estimator for the determination of trend and slope magnitude. Monthly precipitation trend has been identified here to achieve the objective, which has been shown with 115 years of data. The Mann–Kendall test and Sen's estimation tests indicated significant changing patterns in the frequency and intensity of the rainfall across the Sikkim in an intra-decadal time series domain. It has been noted in this study that the Sikkim region observed drastic rainfall pattern changes after 2001, because of which there was an increase in disasters like landslides and floods., This study also used inverse distance weighted (IDW) interpolation method and reclassify tool to produce the maps for identifying the pattern and region that caused more rainfall. NDVI (Vegetation Index) has also shown the drastic changes in south Sikkim of vegetation due to decreased rainfall, urbanisation. NDVI values gradually risefrom spring to rainy season and fall steadily from autumn to winter.

Sikkimite: A New and Rare Suite of Potassic-perpotassic Syenites from South Sikkim, Lesser Himalaya, India

Abstract A new and rare suite of radioactive, plutonic-hypabyssal, nonperalkaline to peralkaline, potassic to perpotassic syenites have been reported as dyke-like and/or lensoid bodies (c. 100 m x 20 m to 5 m x 2 m) within the Buxa and Daling formations (Proterozoic) and Gondwana Group of rocks (Permo-Carboniferous) within the Ranjit tectonic window (RTW) and its peripheral parts in south Sikkim. These are christened in this work as ‘Sikkimites’ considering their unique field occurrences, petrography, mineralogy and geochemistry, unlike any known saturated potassic - perpotassic syenites from the plutonic environment from India or elsewhere. The modal (vol.%) mineralogical variations observed within the potassic syenites include orthoclase (57-65%) with subordinate to minor amounts of brown alkali amphibole (kataphorite, 3-32%), aegirine (1-20%), biotite (13% in one sample), opaque minerals (ilmenite and magnetite, 4.2-24.5%), quartz (traces to 12.9%) and minor to trace amounts (< 3%) of apatite, sphene, zircon, and monazite. Compositionally, the Sikkimite suite range from non-peralkaline to highly peralkaline types (with Mol. Na2O + K2O/Al2O3 varying from<1 to1.2 to 1.5), mildly-perpotassic (Mol. K2O/Al2O3>0.83 to 0.96) and perpotassic (Mol. K2O/Al2O3>1 and Wt.% K2O/Al2O3 = 2.52-23.9) and Wt.% K2O/Na2O(3.05-23.9). The potassic syenites shows wide variations in major, minor and trace elements with significant enrichments in TiO2, Ba, REE, Y, Zr and Nb. The petrogenetic model for these rare potassic syenite suite of rocks (termed here as Sikkimite) invokes a near-primary origin by partial melting of enriched, amphibole- and phlogopite-bearing heterogeneous mantle, having chemical signatures of both non-subduction and subduction-related metasomatism. Ar40-Ar39 dates on them indicate a Cretaceous age (100-90 Ma) suggesting their links to either the widespread igneous manifestation of the Kerguelen or the Marion plume of the Indian Ocean.. These rare potassic syenites were apparently brought to the near surface environments in south Sikkim due to the collision of Greater India with Asia and the ensuing Himalayan thrusts from the north (MCT1 and MCT2) which shifted the crystalline basement and the Gondwana rocks maximum to the south, unlike any other parts of the Himalaya.

An assessment of the water quality index (WQI) of drinking water in the Eastern Himalayas of South Sikkim, India

The current research was performed to evaluate the Water Quality Index (WQI) from the South Sikkim district, India, in the Eastern Himalayan region. Due to the rapid development of the tourism industry in the region, water scarcity has become one of the significant issues in some parts of the South Sikkim district. The lack of sufficient spring water to meet their drinking water needs has forced the local people to depend on alternate sources such as surface or rainwater. The main aim of the current research is to determine the acceptability of drinking water sources using the Water Quality Index (WQI) values. The Bureau of Indian Standard (BIS 2012) was used to evaluate the WQI and evaluate the quality of water for the water sources. Physicochemical parameters such as potential of hydrogen (pH), hardness, alkalinity, iron (Fe), fluoride (F−), chloride (Cl−), nitrate (NO3−), and turbidity were analysed using standard devices and found that water is safe for drinking purpose. The presence of all these parameters did not affect the water quality as all are below the permissible limit. The water delivered after conventional treatment to individual households by local administration is free from contaminants and suitable for drinking. Based on WQI values, surface waterfalls under the projected area of South Sikkim district into two categories: excellent water and good water (ranging from 0 to 50). However, water scarcity continues to remain a major challenge. The current study concludes with some suggestions for proper planning and managing drinking water resources in the South Sikkim district and hilly areas.

Uses of ethnomedicinal plants by the people living around Kitam Bird Wildlife Sanctuary, South Sikkim, India

The utilization of wild medicinal plants in primary healthcare system is still vital for mankind, particularly for people residing nearby the protected area. However, ethnobiological knowledge of indigenous people on plant usage is diminishing. The present study aimed at documenting the wild ethnomedicinal plants and to evaluate their importance in the healthcare among the local inhabitants in the fringe villages of Kitam Bird Sanctuary, South Sikkim, India. The methodology comprised interviews and questionnaire-based household surveys focusing on the informant's knowledge and experience in the use of wild medicinal plants against several diseases and ailments. Data was analysed using relative frequency citation (RFC), use value (UV), informant consensus factor (ICF) and fidelity level (FL%). A total of 23 ethnomedicinal plant species belonging to 20 families were recorded from the study area. Among the growth forms, herbs accounted the highest number of species (39%), followed by trees (30%), climbers (13%), ferns and shrubs with 9% each. Fruits have shown the highest use (20%), followed by leaves (16%) and whole plant. Terminalia chebula had the highest RFC (0.91) and UV (0.99), followed by Terminalia bellirica (RFC = 0.89, UV = 0.96) and Phyllanthus emblica (RFC = 0.84, UV = 0.91). Results indicate that the locals in the area had good ethnobotanical knowledge of medicinal plants which indicates their dependency on plants for treating several ailments and diseases. Some unexplored species such as Calamus erectus, Laportea bulbifera, Pteris biaurita and Solanum viarum possessing high fidelity level have scope for further pharmacological investigation.

Impact of climate change on crop water and irrigation requirements over eastern Himalayan region

Due to climate change, the agricultural and socio-economic development over the eastern Himalayan region of India is greatly affected. The present study has been carried out to investigate the implications of climate change on regional crop water requirements (CWR) and crop irrigation requirement (CIR) of major crops (maize, wheat and, rice) over a Himalayan state, i.e., Sikkim. Daily climatic datasets such as rainfall, minimum temperature, maximum temperature, wind speed, sunshine hours, and relative humidity are used for this analysis along with crop and soil data. For future period (2021–2099), climatic datasets are collected from the four climate models (ACCESS1-0, CCSM4, CNRM-CM5 and MPI-ESM-LR) of CORDEX under two different scenarios, i.e., Representative Concentration Pathway (RCP) 4.5 and 8.5. CWR & CIR of maize, wheat and rice crops are projected for three-time windows, i.e. start term (2021–2046), mid-term (2047–2073), and end term (2074–2099) by taking 1998–2015 as baseline period. In addition, uncertainty and sensitivity analysis is carried out. The outcomes from the study suggest an increase in the CWR towards the end of the twenty-first century for rice and wheat over West (8% and 39%) and South (11% and 37%) Sikkim with respect to baseline period. In case of Maize, a decreasing trend is noticed over West (− 4%) and East (− 15%) Sikkim. For all the crops in East Sikkim, a declining trend is likely to occur. In most of the cases, the CIR has increased towards the end of the twenty-first century. The uncertainty analysis reveals RCP 4.5 as the possible scenario over the study area. The outcomes from the study facilitate the agricultural and water managers for adopting effective measures to ensure sustainability.

Climate Change Impact on Socio-cultural and its Vulnerability Assessment in Himalayan District of South Sikkim, India

Climate Change Impact on Socio-cultural and its Vulnerability Assessment in Himalayan District of South Sikkim, India

Morphological characterization and secondary metabolites profile of black pepper (Piper nigrum L.) genotypes from Sikkim

Quantification of volatile oil and analysis of four major metabolites using HPLC was done in 24 black pepper genotypes collected from south Sikkim. The amount of volatile oil ranged from 2.01% to 0.022%. Secondary metabolites like piperine ranged from 2.75-0.022%, myrcene from 2.094-0.022%, alpha- phellandrene from 1.373-0.008% and linalool from 0.834-0.012%. Genotype 23 had the highest amount of myrcene and linalool, genotype 13 had the highest quantity of piperine and genotype 8 had high amount of alpha-phellandrene. The principal component analysis (PCA) of analyzed metabolites grouped the genotypes into four categories. The study revealed that some of the genotypes were as good as pepper varieties grown in traditional areas. These genotypes will be useful in crop improvement strategies and suitable for Sikkim Himalaya.

Business Plan for a Start up Hotel: A case study on Hotel Ravangla Star, South Sikkim

Business Plan for a Start up Hotel: A case study on Hotel Ravangla Star, South Sikkim

Precipitation analysis for the East and South districts of Sikkim, India

This study emphasizes the rainfall analysis in the state of Sikkim located in the north east region of India, which covers up an area of 7097 km2. The rainfall analysis of the two districts East Sikkim and South Sikkim for a period of 118 years (1901-2018) are computed. Various tests depicting the trends, homogeneity, slope and statistical data reveals the monthly, seasonally and annual rainfall pattern in these districts of Sikkim. For the annual rainfall, the coefficient of variance varies from 13% to 19% whereas the coefficient of variance for seasonal rainfall varies from 14% to 81% which indicates that seasonal variability is more than the annual variability. Southwest monsoon contributes 79% to the annual rainfall followed by pre-monsoon which contributes 14% to the annual rainfall. The trend analysis depicts an insignificant increasing trend annually but a significantly decreasing trend for the south west monsoon with a negative slope justifying the downward trend. The homogeneity test points out the specific year the trend of the rainfall begins which was found to be in the year 1955.

Quantitative analysis of vegetation structure, composition and species diversity of moist Sal bearing tropical forest of Sumbuk reserve forest in South Sikkim, India

Quantitative analysis of vegetation structure, composition and species diversity of moist Sal bearing tropical forest of Sumbuk reserve forest in South Sikkim, India