Sikkim District Research Articles

The insight of agricultural adaptation to climate change: a case of rice growers in Eastern Himalaya, India.

Adaptation is crucial to curb down the negative impact of climate change particularly on agricultural sector. Hence, a study was conducted to identify the strategies adopted by the cereal growers in Eastern Himalaya region of India and determine the factors affecting them. A total 120 farmers were surveyed from Senapati district in Manipur and East Sikkim district in Sikkim. The widely adopted strategies were the change in transplanting time and change in transplanting as well as harvesting time, which were autonomous, traditional, and taken in response to the scarcity of water. Tobit model has identified that the area under rice cultivation, support received from Village Science Centre, and decline in food availability positively influenced the farmers to adapt to climate change. Multinomial logit model revealed that the female farmers, area under rice cultivation, and decline in rice productivity positively influenced the adoption of the strategies, whereas number of cattle owned, irrigated area, and support from Agricultural Department revealed the negative influence. To sustain farming in hill agriculture, the study recommends the integration of the farmers' knowledge along with scientific measures. Planned intervention, viz., in the form of construction of water harvesting structure, should be initiated by the State Government.

<b>A new record of the lesser-known butterfly Small Woodbrown <I>Lethe nicetella</I> de Nicéville, 1887 (Lepidoptera: Nymphalidae: Satyrinae) from Kangchendzonga National Park, Sikkim, India</b>

This study reports the recent sighting of Small Woodbrown Lethe nicetella from Khangchendzonga National Park in West Sikkim District, India. It was originally described by de Nicéville (1887) based on the collection of males and one female by Otto Möller from Sikkim but the exact type locality was unknown. We also reviewed various historical and contemporary reports on the description and distribution of this species. We did not find any report of collection or sighting of the species from India after Elwes & Möller (1888). The occurrence of this species in Sikkim is mentioned in Haribal (1992) but it is not clear whether the report is based on sightings or historical records because sighting location is not given, indicating its description based on museum specimens. Hence, we conclude that the Small Woodbrown L. nicetella was sighted after a gap of around 120 years. Further, we have provided the first photographic records of a live individual of this species from India. Our finding indicates a possibility of existence of many cryptic taxa that should be explored using morphological and molecular approaches.

Notes on the Distribution of a Rare and Little Known Species: Allium fasciculatum Rendle from Sikkim and West Bengal

Germplasm of a rare and lesser-known species Allium fasciculatum Rendle was enriched through exploration undertaken in interior parts of North, South and West districts of Sikkim (1300–2600 m) and Darjeeling in West Bengal where it was reported for use as vegetable and condiment. This species, a rare and economically useful plant species growing in the kitchen gardens/backyards in the area of exploration, forms a new record on cultivation with addition to the germplasm holdings in field genebank at ICAR-NBPGR regional station at Bhowali, Uttarakhand.

Morphological and Phylogenetic Evidence for Two NewLactariusSpecies (Russulales, Basidiomycota) from India

Lactarius ferruginascens sp. nov. and L. indoaquosus sp. nov. are described from the East and South districts of Sikkim, a small Himalayan state in India. Macro- and micromorphological descriptions coupled with the illustrations and nrITS-based molecular analyses are given for both species. Lactarius ferruginascens is a species in L. subg. Plinthogalus with striking features such as a sticky pileus surface caused by the ixohymeniderm structure of the pileipellis, watery white latex which is turning rusty brown on the lamellae and the occurrence under Abies sp. in the subalpine mixed forest. Lactarius indoaquosus is a new representative of L. subg. Russularia with completely transparent and unchanging latex and is furthermore characterized by basidiospores with a zebroid ornamentation, the absence of hymenial macrocystidia and the occurrence under Castanopsis sp. in the temperate broadleaf forest. Both species are illustrated and compared with related taxa.

A note on the Gadi Central Pandam Sacred Grove of East Sikkim, Sikkim, India.

Sacred groves are small forest patches conserved by local people through socio-religious and historical beliefs. Gadi Central Pandam is one of the oldest sacred groves and protected more than 300 years due to its various religious, historical and archaeological significances. It is situated in the Sumin Resrve Forest of Rangpo Block of East Sikkim District. The sacred grove harbors a wide variety of plant species. This grove is facing serious threats due to various developmental activities. Therefore, it is suggested here to create awareness among the native people about the traditional values of this sacred grove and environmental benefits to the region and better sustenance of mankind by conserving the biodiversity of the region. The native people should also be encouraged to involve actively in protection and sustainable conservation managements of this grove for posterity.

Developing water resources management strategies for South Sikkim District, India

Abstract This study was an effort to analyse the problems and prospects of water resource management and for suggesting strategies to meet the perceptive demand of 410 L of water per family during the winter period in South Sikkim district of Sikkim state, India. The district is of hilly terrain with an average rainfall of 1,500 mm per year, yet the district faces acute water shortage during the winter period. The hydro-geological and meteorological characteristics of the sub-watersheds were also studied. The district had very poor soil depth (<50 cm), low water holding capacity of soils (27–28%) with mostly sandy-loam texture. The sub-watersheds were found to have more than 70% first-order streams, higher bifurcation ratio (3.31), higher drainage density (3.99 km/km2) and higher stream density (8.65/km2). Sub-watersheds are mostly elongated with average form factors of 0.21. The rainfall pattern, soil type and morphometry of sub-watersheds indicated poor in situ moisture storage and limited possibility of stream water harvesting. To mitigate the scarcity of water in South Sikkim, the only option left for the planners is to promote household roof water harvesting so that water demand can be met during the average consecutive dry period of 30 days.

Female plants and range extensions in Scapania davidii Potemkin (Scapaniaceae, Marchantiophyta)

Scapania davidii Potemkin, previously known from the Xizang district of China, East Nepal and India (West District of Sikkim), is now reported from Bhutan and the North and East Districts of Sikkim and Anjaw District of Arunachal Pradesh in India. Female plants with well-developed perianths are described and illustrated here for the first time. The differentiation of S. davidii from S. ornithopoides (With.) Waddel is discussed. The distinguishing features of S. davidii are hemispherically convex, broadly oval to nearly reniform leaf lobes, the subequal size of the dorsal and ventral lobes resulting in the formation of very compact head-like shoot apices, the decurrency of the dorsal lobe, contrasting deep brown pigmentation of marginal teeth, formation of variable paraphyses in the axils of vegetative leaves and the male and female bracts, and the morphology of the perianth with 1–2-celled cilia on its inner surface closer to the perianth-mouth. An expanded description, illustrations and map showing the spatial distribution of vegetative, male and female plants are provided.

The Tibetan Wolf Canis lupus chanco Gray (Mammalia: Carnivora: Canidae) in northeastern India with a recent sighting from northern Sikkim, India

The Tibetan Wolf Canis lupus chanco which is a relatively rarer subspecies of the wolf C. lupus occurs in Sikkim in North-east India with unconfirmed reports from Arunachal Pradesh. Its range in Sikkim is in the high elevation areas. There are very few sighting records from the state. This article reports an observation made recently between Thangu and Gyagong or Gogong in North Sikkim district at 4,250m elevation on 17 April 2014. Presence of feral dogs are threats to the Wolf as well as its prey base. Â

Correlation studies for effect of fruit grade on fruit quality and seed traits of mandarin variants in North East India

Field experiments were conducted during 2007–10 at ICAR Sikkim Centre, Tadong located at 1,400 m amsl to identify the suitable grade of fruits for raising nucellar nursery and fresh fruit marketing of Sikkim mandarin. Small and large sized fruits were collected from all the four districts of Sikkim. The highest fruit weight (161.25 g/fruit), waste index (1.14), TSS: acid ratio (8.00) and number of healthy seeds per fruit (19.5) were recorded. Maximum juice (53.2%), minimum waste index (0.68) and number of healthy seeds (7.1) were found in small fruits. Negative correlation between specific gravity and number of healthy seeds per fruit (−0.714) was observed. Waste index of fruits revealed significant positive correlation with healthy seeds per fruit (0.727) and total seed weight (0.721), while negative correlation with fruit shape index, specific gravity and juice content. Big sized fruits possessed high number of good quality seeds per fruit, which can be used for nursery raising as well as for fresh fruit marketing purpose, whereas small sized fruits with higher juice percentage can be recommended for fresh juice preparation.

Mollitrichosiphum spp: A new record of aphid from Alder-large cardamom ecosystem in Sikkim

Aphids (Hemiptera: Apihidoidea) pest problems were well known worldwide. A total 823 species in 222 genera and 18 sub families of the family Aphididae were known from the Indian sub continent. In Eastern Himalayas and North East India, 464 species in 147 genera in 15 sub families of aphids were known to be available. Sikkim belonged to NE India. From Sikkim, 26 important Aphids were reported so far. Three species of aphids were known to be associated with Alder ( Alnus nepalensis ) in North East India. Large cardamom ( Amomum subulatum Roxb.) was an important cash crop of Eastern Himalayan region. It was sciophytes i.e., the plant grew under shade. The crop grew somewhat wild in nature and damage due to insect pests was common. It was infested by various pests and diseases causing considerable amount of monetary loss. Surveillance was conducted in alder - large cardamom ecosystem in four different districts of Sikkim during 2011 to 2013. Mollitrichosiphum spp reported for the first time from Sikkim region. An observation about aphid species associated with alder tree in large cardamom ecosystem in Sikkim was presented.

Forest fire as a potential environmental threat in recent years in Sikkim, Eastern Himalayas, India

Forest fires of short to medium return intervals are quite common during the winter seasons in the state of Sikkim, Eastern Himalayas, India. The forest fires of different intensities were reported from various locations of three districts of Sikkim in the years 2009 to 2011. This paper discusses and analyses the causes of occurrence of forest fires of different severity, in terms of forest area burnt by the formation of conducive atmosphere by the climatic variables such as rainfall, temperature, sunshine hours and humidity during the fire season from 2009 to 2011. These variables were analysed from the forest fire prone months November to April of the years 2009 to 2011. It further highlights that the forest fire disaster is a potential environmental threat in recent years and suggests certain short-term and long-term strategies for mitigation of forest fire in the state.

Geotechnical Aspects of Sikkim Earthquake of September 18, 2011

There was wide spread ground failure and landslide during the recent Sikkim earthquake (Magnitude ML = 6.9) of September 18, 2011. An intensive damage survey was carried out after a week of the earthquake. This paper presents the results of a reconnaissance study in Sikkim. The various geotechnical aspects of the damage caused by earthquake including landslides, failure of retaining walls, foundation failures, damage to roads and creep of soil due to ground shaking have been investigated. The maximum damage was observed in Lachung, North Sikkim district. The paper presents the geotechnical aspects of damages correlating it with level of shaking (intensity on MSK scale) and epicentral distances at different locations. It was found that major damage was due to landslides and failure of retaining walls which in turn are due to movement of soil. In this paper, causes of damages have been investigated and remedial measures, to avoid these in future earthquakes, are suggested.

Damage Survey Report for Sikkim Earthquake of 18 September 2011

A disastrous earthquake of magnitude 6.9 ( M L) struck the Sikkim–Nepal border at 18:11 IST on 18 September 2011. The earthquake left behind a trail of death and devastation, killing about 100 persons, injuring more than 1000, and rendering more than 20,000 homeless. It was located at Latitude 27.723 °N and Longitude 88.064 °E in the India–Nepal border region, with an estimated focal depth of 19.7 km. The fault plane solution shows Nodal Plane 1 having strike N220°, dip 78°, and slip 0°, whereas Nodal Plane 2 corresponds to strike 130°, dip 90°, and Slip (rake) 168°. The location of the earthquake and its fault plane solution was also reported by Indian Metrological Department, New Delhi. The magnitude was reported to be 6.8 with occurrence time 18:11 h IST, on 18 September 2011 in the Sikkim–Nepal border region. The fault plane was shown to be strike slip. De and Kayal (2003) observed that earthquakes in this region occur with strike‐slip mechanism in the mid crust, at a depth range of 10–25 km. The focal mechanism of this earthquake further reconciles the fact that crustal shortening in the Sikkim Himalaya has been substantially accommodated by transverse tectonics rather than underthrusting in recent times (Hazarika et al. , 2010). The North Sikkim district was the worst affected area. The main cities and towns in Sikkim which suffered major damage to built environment include Gangtok, Lachung, Singhtham, Mangan, Jorthang, Legship, Geizing, and Rangpo. The earthquake was reported to be widely felt in adjoining states of Assam, Meghalaya, northern parts of West Bengal, Bihar, and parts of other eastern and northern regions of India. The authors visited the damaged area during 24–29 September 2011, and carried out a detailed damage survey. The main objective of the team conducting the post‐earthquake damage survey was to study and document the macroseismic …

Morphological characterization of indigenous chickens of Sikkim and West Bengal, India

The study was conducted to characterize the variations in physical characters and some important feather and skin mutations observed in different populations of native chickens of West Bengal and Sikkim, India. The data encompassing eight different phenotypes such as, naked neck chicken, frizzled chicken, muffed/bearded chicken, creeper chicken, crested chicken, rumpless chicken, feathered shank chicken and fibromelanosis chicken, were collected from six districts of West Bengal and two districts of Sikkim. Seven qualitative traits such as colour of the egg shell, feather, skin, shank, comb and earlobe as well as the type of feather, and three quantitative traits such as shank length, egg weight and body weight, were assessed in a total of 2 170 fowls of both sexes. The data were analysed statistically using descriptive statistics, the differences in means were compared using Duncan's multiple range test and ?2 was used for non-parametric characters. Each of the populations had multiple variants and mixed feather colours were seen in most of the chickens while the feather, skin and shank colours were all black in fibromelanosis chickens. The shank colour was predominantly blue, followed by yellow and white. The skin colour in most of the chickens was white. Most of the chickens had a single comb (except for the crested chicken). The highest body weight was observed in the desi chicken while the rumpless chicken weighed the least. The egg-shell colour varied between cream and light brown in all the flocks except for the fibromelanosis chicken whose egg-shell colour was tinted bluish. The highest recorded egg weight was observed in the naked neck chicken, whereas the hatchability and egg weight were the lowest for the rumpless chicken. In the recent years, it has been observed that there is a significant reduction in the population of native chickens. This may be attributed to the restocking with Rhode Island Red and synthetic Kruilor chickens following the avian influenza outbreaks in the region. Hence, immediate steps need to be taken to preserve whatever is left in the native chicken ecotypes in the region.

New distributional record of a rare sedge Kobresia (Cyperaceae) from Sikkim, India

Kobresia harae Rajbh. et H.Ohba (Cyperaceae) is reported for the first time from India. Nomenclature, description, phenology, habit, habitat, distribution and illustrations are provided here. The species is known so far from North Sikkim district only.

A case series and review of sporotrichosis in Sikkim

Sporotrichosis caused by the fungus Sporothrix schenckii has been widely reported from the northern Himalayan belt and the north eastern region of India. Three autochthonous cases of lymphocutaneous sporotrichosis from east and south districts of Sikkim are reported. Fluid aspirate from the nodulo-ulcerative lesions were sent for cytology and fungal culture. S. schenckii was isolated on culture and cytological examination in all three cases showed granulomatous reaction. Thermal dimorphism was demonstrated and animal pathogenicity testing was performed. Saturated solution of potassium iodide was used for treatment and the last case was treated with itraconazole and potassium iodide. Awareness of this disease and an extensive environmental study is required to understand the actual burden of this disease.

Macroseismic study of 20th May 2007 Sikkim earthquake — Its seismotectonic implications for the region

An earthquake of magnitude 5.0 with its epicenter in the West Sikkim district occurred on the evening of 20th May 2007. The macroseismic study revealed an ENE-WSW isoseismal pattern indicating a trend conforming to that of the major tectonic discontinuities in this part of the Himalaya.

Distribution of Frankia genotypes occupying Alnus nepalensis nodules with respect to altitude and soil characteristics in the Sikkim Himalayas

We investigated the distribution of Frankia genotypes with respect to three altitudinal zones in the Sikkim Himalayas. The study was carried out for 90 Alnus nepalensis trees at nine different locations from three altitudes from the east and north districts of Sikkim, India. We used a PCR‐based technique to amplify the internally transcribed spacer (ITS) region of the rrn operon using two primers specific for the distal part of 16S ribosomal RNA (rRNA), ITS and proximal part of 23S rRNA genes of Frankia. The PCR products were digested with the restriction enzyme RsaI to generate amplified recombinant DNA restriction analysis (ARDRA) patterns. Frankia genotypes were categorized on the basis of 17 different ARDRA patterns. Nucleotide sequences of some representative amplicons were also obtained. Rhizosphere soil samples associated with the 90 trees were collected and analysed for eight different soil properties. In general, soil properties did not differ by site or altitude, and did not correlate with Frankia genotypes. Frankia community composition was strongly affected by altitude and to a lesser extent by site.

Landslide hazards in eastern Himalayas

The Himalayas, with extreme variations in relief, are characterised by very steep slopes, harsh (i.e. cold and humid) climate and a dynamic geotectonic setting. These characteristics appear responsible for widespread slope failures and mass movements, which are often accentuated by various human activities. The importance and severity of landslide phenomenon was not recognised until recently because of sparse habitation, remoteness of its occurrence, and limited sphere of influence of the individual slides. During the last few decades, increasing developmental activities, such as unplanned urbanization, communication, dam construction, deforestation, and agriculture, have substantially affected the geo-environment and aggravated the landslide hazard in the eastern Himalayas.
 Three sample areas: i) along the National Highway 31 A (the East Sikkim District), ii) in the area of the Rarnmarn Hydroelectric Project Stage II (the Darjeeling District), and iii) in the Kalimpong Municipal area (the Darjeeling District), all within the inner tectonic belt of the Lesser Himalaya, were investigated for preparing LHZ maps on 1:25,000 scale. Landslide hazard evaluation factors (LHEF) were rated for each of the major causative factors, namely lithology, structure, slope morphometry, relative relief, land use, and drainage density, and summed up to obtain the total estimated hazard (TEHD) values for each slope facet. The TEHD values from 0 to 10 were classified into live zones of increasing relative hazard.

On some plant fossil from Gondwana equivalent sediments of Eastern Himalaya

The plant fossils reported here were recovered from Gondwana equivalent continental facies outcropping in Kameng District (Arunachal Pradesh), South Sikkim District (Sikkim) and Darjeeling District (West Bengal). The flora comprising equisetalean axes, Phyllotheca sp., Glossopteris stenoneura Feistmantel, G. communis Feistmantel, G. sp. cf. G. leptoneura Bunbury, G. syaldiensis Chandra & Surange, G. formosa Feistmantel and Vertebraria indica Royle resembles that of the Late Permian Raniganj Formation of peninsular India.