Eastern Himalayan Region Of India Research Articles

Growth and production potential of buckwheat genotypes under organic farming in the Eastern Himalayan region of India

Growth and production potential of buckwheat genotypes under organic farming in the Eastern Himalayan region of India

Sustainable solid waste management challenges in hill cities of developing Countries: Insights from eastern Himalayan smart cities of Sikkim, India

Rapid urbanization and the growing tourism industry in the Himalayan region have raised significant concerns about the sustainable handling and management of solid waste in the area. This concern is particularly pronounced in the unique and vulnerable ecosystem of cities nestled in the eastern Indian Himalayas, where geography, ecology, and socio-economic factors converge to create distinctive challenges. This study undertakes a thorough investigation of solid waste management practices and challenges in two smart cities nestled in the eastern Himalayan region of India, specifically Gangtok and Namchi. The primary objective was to unveil the complex challenges confronting these cities by conducting an in-depth exploration of waste management practices. This comprehensive investigation was achieved through the collection of samples, conducting surveys within each ward of the cities, and performing physicochemical characterization analyses. The study also proposes a solution-oriented approach leveraging life cycle analysis. Despite the Himalayan backdrop, waste generation varies significantly, with Gangtok producing substantially more waste (50 tons per day (TPD)) compared to Namchi (4.6 TPD). Both cities excel in waste collection, but Gangtok leads in proactive treatment, with 22% (11 TPD) undergoing composting and recycling. However, shared challenges at riverside disposal sites, including overfilled dumpsites and leachate contamination, pose potential environmental hazards amid the Himalayan allure. Organic waste predominates at 40.9% and 40.01% in both cities, indicating composting potential. Plastic closely at 22.25% (Namchi) and 22.65% (Gangtok) was way above the global (12 %) and national (8.4 %) average respectively, emphasizing the urgency of plastic waste reduction strategy. The 16.95% cardboard in Gangtok highlights potential commerce-related waste. The study also highlights the importance of comprehensive policies for informal sector well-being. The lifecycle assessment of Namchi and Gangtok reveals significant methane emissions (99%) from waste anaerobic decomposition potentially due to poor source segregation. Implementing a futuristic waste strategy reduces emissions by 38% in Namchi and 40% in Gangtok, through biogas utilization and renewable energy adoption. The findings advocate for citizen engagement, improved collection, targeted campaigns, and circular economy principles. To ensure sustainability and resilience in waste management within mountain regions, tailored strategies such as material recycling facilities, community engagement initiatives, and landfill diversion mandates should integrate ecological, socioeconomic, and logistical considerations, fostering awareness and participation among communities.

Urban built-up area footprint (UBAF): A novel method of urban bio-capacity and ecological sensitivity assessment

In the city level, urban ecological footprint (UEF) assessment is used for a variety of measures, from biological resources through people as well as human population as a whole. But, the context of this study is sightly specific, here we focus built-up land consumption coming out the general concept of UEF. This study used to figure out the urban built-up area footprint (UBAF) as well as bio-productive status in a city scale, and its impact on urban ecological sensitivity (UES). For this assessment, one of the fastest growing-up cities in Eastern Himalayan region of India, namely Siliguri Municipal Corporation (SMC) is selected as a study area. To assess the UEF and bio-capacity (BC), the yield and equivalent factors have been introduced. Further, variable weights combination (VWC) method is used to assess the UES of SMC. The result shows that increasing UBAF directly impacted on bio-capacity of SMC area. Most of the lands have been converted into built-up land, and highly ecological deficit is seen in the built-up land areas. Thus, the SMC is already crossed the standard limit of the UBAF limit (>3 ha per capita). Consequently, entire SMC has been ecologically sensitive and facing ecological deficit condition rigidly. Therefore, a UBAF based environmental impact assessment framework has been proposed for city level that can be helpful for the further urban land use planning.

Assessing climate change and its impact on kiwi (Actinidia deliciosa Chev.) production in the Eastern Himalayan Region of India through a combined approach of people perception and meteorological data

Assessing climate change and its impact on kiwi (Actinidia deliciosa Chev.) production in the Eastern Himalayan Region of India through a combined approach of people perception and meteorological data

Canopy Manipulation for Production of Winter Guava (Psidium guajava L.) in the Eastern Himalayan Region of India

Elimination of rainy-season crops is pivotal to encourage winter crops in guava. In general, rainy-season guava fruits are of poor fruit quality, insipid in taste, have poor shelf life, and mostly affected by many insect pests. Pruning is also considered one of the most eco-friendly methods for crop regulation. To fully comprehend the impact of pruning time and severity on flowering, fruit quality, and crop production, a field experiment was carried out. Three alternative pruning times (mid-April, mid-May, and mid-June) at different pruning levels (low, moderate and heavy pruning) were employed in the experiment, which was designed as two-factor factorial RBD. For obtaining optimal fruiting, size of fruit and quality of fruit attributes, mid-May pruning has proven to be the best time for guava pruning. Whereas, concerning pruning severity, moderate pruning (pruning 1/2 of the current season’s shoot length) showed a good response to yield and fruit quality parameters. Therefore, the present study concluded that moderate pruning of guava trees during the month of mid-May proved to be the most effective for producing winter-season guava with good yield and superior quality.

Variation of phosphorus pools as affected by land use in acidic soil of eastern Himalayan region of India

Soil phosphorus (P), an essential major element is mostly low in many tropical and sub-tropical soils and its characterization into different pools and relationship with other soil properties is crucial in understanding the adsorption chemistry and its release to available forms. Three soil depths (0–15, 15–30 and 30–45 cm) from six major land use were studied to elucidate the effect of land use on different pools of soil P and its relationship with other soil properties. The studied soils were acidic in nature (pH: 5.03–6.33) and land use significantly increased the soil pH for lowland rice (LR: 6.1), the higher soil pH in LR soil also significantly increased the available P forms (available P: P and Mehlich P: M-P) while the higher clay content in Teak (T) plantation decreased the available P forms implying that P was fixed. In addition, soil pH was positively related to the labile inorganic pool (NaHCO3-PI) and stable pool (HCLP). The moderately labile pool, NaOH-P (16–44%) was higher compared to labile pool, NaHCO3-P (11–15%) and stable, HCL-P (2–13%) due to the acidic soil pH where Fe and Al oxide dominates in sub-tropical weathered soils. The organic P pools (NaOH and NaHCO3) which is important for long term P cycling were higher than the inorganic pools in T, F and R land uses. Management strategy for increasing SOC is important to maintain organic P cycling to supply available P for long term.

Conservation tillage and diversified cropping enhance system productivity and eco-efficiency and reduce greenhouse gas intensity in organic farming

Environmental pollution, resource dwindling, and soil degradation questioned the sustainability of contemporary agricultural production systems. Organic farming is advocated as a sustainable solution for ensuring food security without compromising environmental sustainability. However, poor farm productivity quizzed the sustainability of organic production systems. Hence, a field study was carried out in the Sikkim region of the Indian Himalayas to assess the efficacy of conservation-effective tilling and diversified cropping on system productivity, profitability, environmental quality, and soil nutrient balance in organic farming. Three tillage systems, namely, (i) conventional tillage (CT), (ii) reduced tillage (RT), and (iii) zero tillage (ZT), and four maize based diversified cropping systems (maize–black gram–toria, maize–black gram–buckwheat, maize–rajmash–toria, and maize–rajmash–buckwheat) were tested using a three times replicated split-plot design. The ZT system recorded 13.5 and 3.5% higher system productivity over CT and RT, respectively. Of the four diversified cropping systems, the maize–rajmash–buckwheat system recorded the maximum system productivity (13.99 Mg ha−1) and net returns (3,141 US$ ha−1) followed by the maize–black gram–buckwheat system. Among the tillage practices, ZT recorded the significantly high eco-efficiency index (EEI; 1.55 US$ per kg CO2-eq emission) and the lowest greenhouse gas intensity (GHGI; 0.15 kg CO2-eq per kg production). Of the diversified cropping systems, the maize-rajmash-buckwheat registered the lowest GHGI (0.14 CO2-eq per kg production) and the highest EEI (1.47 US$ per kg CO2-eq emission). Concerning soil nutrient balance, after three cropping cycles, the soil under ZT recorded significantly higher available N (340.0 kg ha−1), P (16.6 kg ha−1), and K (337.3 kg ha−1) over the CT system at 0–10 cm soil depth. Similarly, the soil under the maize–black gram–buckwheat system had the maximum bio-available NPK. Thus, the study suggests that the cultivation of the maize–black gram/rajmash–buckwheat systems under ZT and/or RT would increase farm productivity, profitability, and soil fertility with minimum GHGI in organic farming under the Eastern Himalayan region of India.

Cross-Cultural Comparative Analysis of Technological Gap between Tribal Pineapple Growers of Meghalaya, India

The varied agro-climatic condition of Meghalaya favours cultivation of different horticultural crops, particularly different fruit crops, and pineapple is the most notable of them. The present study was conducted on 200 tribal pineapple growers of Meghalaya in the North Eastern Himalayan region of India in the year 2017-2018. The article highlighted the technological gap among pineapple growers with special emphasis on the differences in agro-economic, socio-psychological and extension-communication characteristics between the Khasi and the Garo tribes of Meghalaya in the north-eastern Himalayan region of India. The average level of the technological gap of Garo farmers (61.78%) was slightly higher than that of Khasi farmers (57.85%). The Mann-Whitney U test reported that the mean scores of the technological gap for the farmers of West Garo Hills and Ri Bhoi were indicating a significant difference in the technological gap between the farmers of these two tribes. The study suggested the need to understand the differential characteristics of these tribes and to introduce location-specific technologies to minimize the technological gap and increase pineapple production in these tribal areas.

Weather-Based Fruit Fly Population Dynamics Prediction Model for the Mid-Hills of Eastern Himalayan Region of India

Across the globe, it is widely observed that current change in climate or weather pattern has marked effect on insect population dynamics and behavior, though with varied aspects and intensity. Understanding the correlations of insect population dynamics with weather parameters is the fundamental first step in formulating an effective integrated pest management programme. In the major citrus growing mid-hill regions of Arunachal Pradesh, fruit fly, Bactrocera dorsalis, is one of the chief reasons for heavy loss leading to pre-harvest fruit drop in citrus. The current study aims to determine how changes in weather parameters influence the population dynamics of fruit flies and to develop an optimized weather-based population prediction model for fruit flies infesting citrus in the mid-hills of Arunachal Pradesh. The population was monitored through standard methyl eugenol para-pheromone traps and a model was developed using stepwise multiple regression technique. The study revealed that the population was highest during the fruit development and ripening stage and it was found that the number of flies per trap and meteorological parameters (temperature and humidity) is positively correlated with appreciable statistical significance. The optimized regression model was developed with variables temperature and humidity, and was found to be 79 percent accurate in the study site. This model will serve as an important tool in pre-estimation of the fruit fly population in the citrus growing mid-hills of Arunachal Pradesh and for formulation of effective preventive management strategies.

‘When orange becomes sweeter’: understanding climate variability, situated knowledge and development in an Eastern Himalayan region of India

In contemporary times, climate variability has spurred interdisciplinary efforts to gauge the impacts of climate change. Drawing from field-based research in Arunachal Pradesh, India, this paper explores what constitutes ‘climate knowledge’ when bio-physical environmental changes are perceived differently among community members. To associate bio-physical realities with socio-cultural knowledge and practice, it is necessary to shift the frame of reference. This enables an interdisciplinary study of climate change that is more productive for both natural sciences and interpretative social sciences. We also discuss the hybrid nature of climate’s ontological and material relations emerging from colonialism, capitalism, and development, which further shape the relationship between community and environment. Finally, the article discusses the loss of Indigenous communities’ cosmological world-making practices in the context of weakening traditional livelihood practices and social cohesion. The paper suggests that climate change needs to be considered not only as a loss of biodiversity but also as a loss of culture when it comes to interpreting the environment.

Chemical composition, antioxidant activity and bioactive constituents of six native endangered medicinal orchid species from north-eastern Himalayan region of India

Orchidaceae is one of the largest and most diversified group of flowering plants within the families of angiosperm. Medicinal properties of orchids are less explored, but it is drawing significant attention of the scientific communities recently. The north eastern Himalayan region of India is well-known orchid hotspot with prevalence of two-third of total orchid species of the country. In the present study, an attempt was made to investigate the phytochemical composition of six native, endangered medicinal orchid species of this region namely Dendrobium nobile, Dendrobium moschatum, Dendrobium densiflorum, Acampe papillosa, Coelogyne nitida and Arundina graminifolia . The nutritional as well as phytochemical composition and antioxidant activity of the extracts were analyzed by spectrophotometric methods. Minerals were estimated by atomic absorption spectroscopy (AAS) and flame photometer. Quantification of phenolics and bioactive metabolites from methanol extracts of the selected orchid species were carried out by high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GCMS) methods. Results revealed that Dendrobium moschatum contained highest total carbohydrate (6.49 g 100g −1 ) and protein (11.30 g 100g −1 ). Dendrobium densiflorum was rich in total flavonoid content (35.54 mg quercetin equivalent QE 100g −1 ) and total alkaloid content (11.70 g 100g −1 ). It also showed highest 2, 2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging activity (64.4 µg ml −1 ). Acampe papillosa exhibited maximum total phenol content (4.09 g gallic acid equivalent GAE 100g −1 ), tannin (3.17 g tannic acid equivalent TAE 100g −1 ) and saponin (7.20 g 100g −1 ) content whereas Coelogyne nitida showed 281.7 µg ml −1 2, 2-diphenyl-1-picryl-hydrazyl (DPPH) scavenging activity. Iron, zinc, copper, manganese, sodium, potassium and calcium contents were higher in the Dendrobium species compared to other medicinal orchids under study. Quercetin (4518.3 mg kg −1 in Dendrobium moschatum ) and catechin (1211.1 mg kg −1 in Dendrobium densiflorum ) were the major phenolic compounds present abundantly in these orchid species. Metabolite analysis by GCMS showed presence of total twenty-six major bio-active compounds (like dendroban-12-one, embramine, scoparone etc.) in these six orchid species. The current study presents scientific evidence in support of the traditional therapeutic application of the studied orchid species and proves that these are potential sources of biologically and pharmacologically active ingredients. • Phytochemical composition analysis and bio prospecting of six medicinal orchids were carried out . • Dendrobium leaves are rich in carbohydrate and minerals but stems are rich in protein content. • Dendrobium densiflorum is rich in flavonoid, alkaloid, zinc, bio active compounds and antioxidant activity. • Acampe papillosa is rich in total phenol, total tannin and total saponin content . • Coelogyne nitida exhibits higher antioxidant activity due to higher quercetin content.

Impact of Live Mulch-Based Conservation Tillage on Soil Properties and Productivity of Summer Maize in Indian Himalayas

Food security and soil sustainability are the prime challenges to researchers and policy planners across the globe. The task is much more daunting in the fragile ecosystem of the Eastern Himalayan region of India. Soil disturbance from conventional tillage reduces soil productivity and is not sustainable and environmentally friendly. Conservation tillage is regarded as the best crop production practice in the Indian Himalayas, where soil is very easily erodible. Zero tillage alone encourages the growth of different species of weed flora in fragile hill ecosystems. However, live mulching of a pulse crop under zero tillage may be a very beneficial practice, as it aids several soil quality benefits and promotes root proliferation with good crop harvest. Hence, a field investigation was carried out for 3 consecutive years to assess the impact of live mulch-based conservation tillage on soil properties and productivity of summer maize. Five tillage practices, viz. no-till (NT), NT and cowpea coculture live mulch (CLM), minimum tillage (MT), MT+CLM, and conventional tillage (CT), were assessed in a randomized complete block design with three replications. Results revealed that continuous adoption of MT+CLM had the lowest bulk density (1.31 and 1.37 Mg m−3) and maximum water holding capacity (48.49% and 43.1%) and moisture content (22.4% and 25%) at 0–10 and 10–20 cm soil layers, respectively, after 3 years. The infiltration rate (2.35 mm min−1) was also maximum under MT+CLM, followed by NT+CLM. MT+LMC had 13.8 and 27.15% higher available nitrogen and phosphorus, respectively, than CT at 0–10 cm soil depth. The MT+CLM gave a significantly higher maize grain yield (2.63 Mg ha−1), followed by NT+CLM (2.63 Mg ha−1) over the others. A cowpea green pod yield of 1.65 Mg ha−1 was also obtained from the legume coculture. Thus, the study found that live mulch of cowpea under MT/NT improved soil quality and subsequently led to greater productivity of summer maize in the Himalayan region of India.

Soil quality restoration and yield stabilization in acidic soils of northeastern Himalayas: Five years impact of green manuring and crop residue management

Soil quality restoration and crop productivity maximization are the global challenge to feed the galloping population. The task is much more daunting in a risk-prone, fragile, and low productive hilly region due to the depletion of supporting and regulating ecosystem services. A five-year long-term (2012–2017) field experiment was conducted to stabilize the yield and soil quality through legume green manuring and crop residue recycling in intensified cropping systems in the Eastern Himalayan region of India. Four treatments involving three green manures [green gram (Vigna radiata); cowpea (Vigna unguiculata);Sesbania(Sesbania aculeata) along with control (no-green manure)], three cropping systems [groundnut (Arachis hypogaea)—pea (Pisum sativum); maize (Zea mays)—pea, and maize + groundnut–pea] and two levels of residue management practices [residue removal and residue retention] were evaluated in three times replicated split–split plot design. Among the green manure options,Sesbaniaexerted a significant positive impact on the soil organic carbon (SOC) stock, available micro- (Fe, Mn, Zn, and Cu), and macronutrients (N, P and K) in surface (0–0.15 m) and subsurface (0.15–0.45 m) soils. The improvement in soil enzymatic activities (acid phosphatase, alkaline phosphatase, dehydrogenase, beta-glucosidase, and aryl sulfatase activity) (p< 0.05) inSesbania-treated soil was +28.1% to +38.9% in surface and +18.3% to +27.3% in subsurface soils over non-green manure.Sesbania-treated soils also exhibited higher soil quality index (SQI) and stratification ratio (SR) of available soil nutrients and enzymes over non-green manured soils. Among the cropping systems, groundnut intercropped with maize followed by peas (MGP) within situresidue retention increased (p< 0.05) the available soil macro- and micronutrients, SOC stock, soil enzymes, SR, and SQI in comparison to other cropping systems.Sesbaniagreen manuring and residue retention improved the yield sustainability by +19% and +11% in the MGP system over non-green manuring and residue removal, respectively. Therefore,Sesbaniagreen manuring in the MGP cropping system along with residue retention is recommended for stabilizing the soil quality through enhancing supporting and regulating ecosystem services and maintaining long-term productivity in the fragile Eastern Himalayan ecosystem of India.

Stability of soil organic carbon pools affected by land use and land cover changes in forests of eastern Himalayan region, India

Forests are among the largest terrestrial carbon pools that are most vulnerable to land use and land cover change (LULC). Therefore, it is essential to manage forest ecosystems to enhance soil organic carbon (SOC) pools and soil functionality. The present study was carried out to analyze C stability and change in SOC stock under different forest types in the eastern Himalayan region of India. Topsoil (0–15 and 15–30 cm) samples from six dominant forests i. e. tropical wet evergreen, montane subtropical, temperate, Quercus, bamboo, and shifting cultivation (Jhum) lands were collected and analyzed for selected soil properties and SOC stock. Active (very labile + labile), slow (less labile), and passive (non-labile) C fractions were also analyzed to determine the stability of the SOC pool under the LULC scenario. Results show that the percentage contribution of active C to total organic carbon in topsoil was highest in a temperate forest (74.1%) while lowest in a bamboo forest (48.1%). Unlike, slow C (18.4%) and passive C (26.6%) were highest in Quercus forest. Pearson correlation analysis shows significant positive relation of active and slow C pool with SOC and total nitrogen concentration. The estimates of SOC stock (0–30 cm) were significantly higher in temperate forests (132.7 Mg C ha−1). However, the conversion of natural forests to bamboo forest and jhum land reduced SOC stock by 29% and 68%, respectively. C lability index shows higher labile C in jhum land while recalcitrancy index was highest in a bamboo forest. Our study concluded that LULC change significantly altered the stability and stock of SOC in natural forests. Owing to a higher percentage of slow and passive C pools, Quercus forests play a major role in C sink management.

Black Carbon Concentration during Spring Season at High Altitude Urban Center in Eastern Himalayan Region of India

This study analyzed the BC associated with PM1 and the contribution of biomass burning to the BC using a portable seven-channel Dual spot Aethalometer in and around Gangtok, the capital city of Sikkim, India, during April 2021. Additionally, CO2 and meteorological parameters (Temperature, Pressure, and Relative Humidity) was measured. The minimum concentration of BC was found in rural areas where the contribution of biomass burning to the BC is highest. The observed spatial variability of BC over Gangtok Municipal Corporation (GMC) area is minimal. Five days back-trajectory analysis was done using the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model to understand the regional influences of air masses at Gangtok. The air mass of the studied region is under influence of trans-regional transport from Indo-Gangetic Plains affecting the BC concentration over the studied region. The black carbon presence in the ambient air near the glacier heights in the Eastern Himalayan region may significantly cause localized warming, thereby enhancing glacier melts. The results have significant bearing for the policy-makers to take corrective steps in addressing the issue of rising BC concentration in high altitude regions. A further detailed study is needed to examine the effect of BC on radiative forcing and its large-scale effect on the East Asian summer monsoon using regional climate models.

Assessing the vulnerability of protected areas in the eastern Himalayas based on their biological, anthropogenic, and environmental aspects

Protected areas are the cornerstone for biodiversity conservation in present times. Considering this, the post-2020 global biodiversity framework aims to expand the network of protected areas to cover 30% of the earth's terrestrial surface by 2030. For effective biodiversity conservation, it is essential to bring in more areas under protection and systematically conserve the areas with greater biological diversity that are relatively more vulnerable to various environmental and anthropogenic stresses. In the present study, we assess the vulnerability of montane forest ecosystems in the protected areas of the eastern Himalayan region of India. Our study specifically classifies the protected areas by their relative vulnerabilities, using established methods based on the number of imperilled species, anthropogenic pressure, and the degree of climate change. The results show that a quarter of the protected areas contain a high species richness of imperilled species; 36% of the protected areas are highly affected by climate change, while only 10% are highly influenced by anthropogenic pressures. Outlining the specific vulnerabilities for protected areas would help determine the required management interventions and promote the judicious use of conservation resources. The analytical framework used in our study can be more widely applied to map the important sites for biodiversity conservation and identify the areas ideal for future expansion.

Rangeland Conservation, Pastoralist Displacement, and Long-term Implications of a Grazing Ban in the Indian Himalaya

Conservation-induced displacement has been one of the major critiques of protected area management across South Asia. While there has been a steady increase in research on physical displacement, studies on loss of mobility remain limited. In 1998, a grazing ban was implemented in the state of Sikkim in the Eastern Himalayan region of India. Livestock herding in protected areas was restricted, and pastoral evictions were carried out across the state between 2000–2002. Fifteen years after the ban, we conducted this study to understand the long-term implications of the prohibition on grazing as well as that of the pastoral evictions in and around Khangchendzonga National Park (KNP). To do so, we assess eviction processes, document pastoral responses, and explore the complex social and perceived ecological outcomes of the grazing ban. Our study shows that pastoral evictions result in the further impoverishment of weaker sections of the pastoral community while powerful pastoralists appropriate benefits from conservation policies. Additionally, evictions do not necessarily aid in “biodiversity conservation”; instead, they give rise to social conflicts within the local community and lead to the emergence of new conservation challenges...

Phytochemical, nutritional and antioxidant potential of Panax bipinnatifidus and Panax pseudoginseng: A study of two underutilized and neglected species from the Eastern Himalayan region of India

The world we live in today is rapidly inclining towards plant-based therapeutic and curative medicines. among these phytomedicines, the role of Ginseng's (Panax species) significance as a functional food or nutraceutical has piqued interest in recent years, with a growing market value. Keeping in mind, the present study was intended to analyse the phytochemical, nutritional content and antioxidant activity of two Indian species of Panax viz. P. bipinnatifidus and P. pseudoginseng from the East Himalayan region of India. HPLC studies revealed the presense of four predominant ginsenosides viz. Rg1, Re, Rb1 and Rd in both the Panax species. Analysis of phenolic compounds indicated higher values of gallic acid, chlorogenic acid, and vanillic acid in both species. The tuber contains a good amount of protein, dietary fibre and carbohydrates. Dominant content of arginine and glutamic acid were found with cysteine and methionine as limiting amino acids in both the Panax species. High levels of palmitic, oleic and linoleic acid were observed with higher values of poly-unsaturates in P. pseudoginseng. Analysis of minerals and trace elements reflected high content of phosphorus, potassium, magnesium and selenium in Panax species. The antioxidant study further confirmed the effective potential of these Panax species against several free radicals such as DPPH, ABTS, and superoxide anions. The present findings provide biochemical insights into the diverse aspects of east Himalayan Panax species coupled with their antioxidant potential. These findings could be used as a baseline model for enriching the herbal raw materials required for pharmaceutical as well as nutraceutical formulations. Moreover, a commercially oriented cultivation of these species may be developed by adopting effective conservation strategies to conserve these therapeutically important east Himalayan Panax species.

Ethnomedicinal plants used by the indigenous tribal communities of Arunachal Pradesh, India: a review

Background: In the absence of modern healthcare facilities in remote rural localities, the indigenous tribal communities of Arunachal Pradesh in the Eastern Himalayan region of India continue to rely on plant-based ethnomedicine for the treatment of various ailments prevalent within their biocultural landscape. This review work has been carried out to document the ethnomedicinal knowledge of the indigenous tribal communities of Arunachal Pradesh by critically perusing the selected published literature. The exploration of ethnomedicinal knowledge of the tribal communities may provide clues for development of new drugs and can also help in the continuity and preservation of such important traditional healing practices. Methods: We downloaded 20 published ethnomedicinal literature (between 2005 to 2019) from online databases such as iMedPub, Academia.edu, ResearchGate, Semantic Scholar, Scopus, Web of Science, Publons, PubMed, etc. using keywords ‘ethnomedicine’, ‘tribes of Arunachal Pradesh’, and ‘North-East India’. The diversity of ethnomedicinal plants, types of ailments treated, herbal formulation, informant consensus and the species and family use values have been quantified using relevant statistical tools and techniques. Results: The present review have reported 358 species of medicinal plants belonging to 100 families used by the fourteen indigenous tribal communities for treating 107 specific types of ailments which are classified under 10 broad categories of ailments, namely, cardiovascular, dermatological, gastrointestinal, general health, gynecological, musculoskeletal, odontological, orthopaedic, respiratory, and urological disorders. Asteraceae has shown the highest use reports per family (86) while Acanthacaeae demonstrated the highest family use value index (UVf) of 4.90. The highest species use report was observed under gastrointestinal disorders with an Informant consensus factor (FIC) of 0.41 while the least species use report was observed under urological disorder (FIC 0.11). Conclusion: Plants showing higher UVf index and FIC in the present analysis should be useful for conservation priority. It will also help in prioritization for in-depth investigation of bioactive phytochemicals of potential medicinal plants effective against reported target ailment categories. Keywords: Ailments, Ethnomedicine, Family use value (UVf), Tribal communities, Informant consensus factor (FIC).

Managing rice fallow lands of the Eastern Indian Himalayas: Impacts of residue management and varietal interventions on soil properties, carbon stocks, and productivity

AbstractDegenerating soil properties, low diversification, and productivity are the major issues for keeping large areas as fallow after rainy season rice (Oryza sativa L.) in Southeast Asia. Long‐duration rice cultivars along with conventional till farming and lack of irrigation facilities limit the chances of growing succeeding crops like pulses in rice fallow areas. Therefore, a field study was conducted to test the hypothesis that cultivating short‐duration rice and lentil (Lens culinaris Medic.) cultivars along with residue retention through mulching or standing rice stubble under no‐till (NT) farming for lentil can enhance the productivity in rice fallow areas and improve economic returns from the cropping system by conserving soil moisture and improving soil properties and carbon stocks. Two rice cultivars (namely, Shahsarang‐1: high yielding and medium duration; and Mendri: local, low yielding, and long‐duration variety), two high biomass lentil varieties (DPL‐81: early duration and IPL‐406: medium duration), and three rice residue management practices (namely, residue removal, 20 cm standing stubble, and mulching at 5 Mg ha−1 in lentil) were tested in the rice–lentil system. After harvest of rainy season rice, lentil was sown under NT using a manually operated furrow opener. Results of a 3‐year study revealed that rice residue retention as mulch at 5 Mg ha−1 and 20 cm standing stubbles (~2 Mg ha−1) conserved residual soil moisture and recorded significantly lower bulk density (1.10 and 1.09 Mg m−3), increased water‐holding capacity (57.05% and 55.14%), and improved water infiltration rate (3.47 and 3.30 cm hr−1) compared to residue removal. Soil organic carbon (SOC), soil microbial biomass carbon, dehydrogenase enzyme activity, available nitrogen, and phosphorus contents at 0–15 cm soil depth were significantly higher by 7.2%–11.1%, 3.9%–6.8%, 4.1%–6.7%, 2.7%–6.4%, and 2.7%–8.0%, respectively, under standing rice stubbles/mulching than residue removal. The SOC stock (25.3 Mg ha‐1) under mulching was significantly higher than that recorded under residue removal at 0–15 cm (23.4 Mg ha−1) and remained non‐significant at 15–30 cm depth. A significantly higher mean seed yield of lentil was obtained under mulching (1.68 Mg ha−1) and standing stubbles (1.49 Mg ha−1) than that under removal (1.27 Mg ha−1). Average productivity of lentil (1.53 Mg ha−1) after medium‐duration rice variety Shahsarang‐1 was greater than that grown after local long‐duration rice variety Mendri (1.43 Mg ha−1). The mean seed yield of early lentil variety DPL‐81 grown after medium‐duration rice was significantly higher (1.60 Mg ha−1) than medium‐duration lentil variety IPL‐406 (1.36 Mg ha−1). Thus, cultivating medium‐duration rice (Shahsarang‐1) followed by early‐duration lentil variety (DPL‐81) and rice residue retention either through mulching or standing rice stubble is recommended for improving soil properties, carbon stock, and productivity of lentil in rice fallow areas of the Eastern Himalayan region of India and other similar agro‐ecosystems.