Western Ghats Research Articles

Investigation of rainfall-induced landslide on unsaturated lateritic residual soil slope in Nilgiris, Western Ghats, India using deterministic and reliability analysis

Investigation of rainfall-induced landslide on unsaturated lateritic residual soil slope in Nilgiris, Western Ghats, India using deterministic and reliability analysis

On-farm crop diversity, conservation, importance and value: a case study of landraces from Western Ghats of Karnataka, India

Landraces are important genetic resources that have a significant role in maintaining the long-term sustainability of traditional agro-ecosystems, food, nutrition, and livelihood security. In an effort to document landraces in the on-farm conservation context, Central Western Ghat region in India was surveyed. A total of 671 landraces belonging to 60 crops were recorded from 24 sites. The custodian farmers were found to conserve a variety of crops including vegetables, cereals and pulses, perennial fruits, spices, tuber and plantation crops. The survey indicated a difference in the prevalence of landraces across the sites. A significant difference with respect to the Shannon-diversity index, Gini-Simpson index, evenness, species richness, and abundance was observed among the different survey sites. Computation of a prevalence index indicated the need for immediate intervention in the form of collecting and ex situ conservation of landraces of some crops as a back-up to on-farm conservation. The study also identified the critical determinants of on-farm conservation, including (i) suitability to regional conditions, (ii) relevance in regional cuisine and local medicinal practices, (iii) cultural and traditional significance, and (iv) economic advantage. The information documented in this study is expected to promote the collection and conservation of landraces ex situ. The National Genebank housed at ICAR-NBPGR, New Delhi conserves around 550 accessions of landraces collected from the Central Western Ghats region surveyed in this report. Information collected from custodian farmers on specific uses will be helpful to enhance the utilization of these accessions.

Conservation Status of Reptilia in Agasthyamalai Biosphere Reserve, Western Ghats, India and its Environment

The Agasthyamalai Biosphere Reserve is an important biogeographical hot spot and hosts diverse ecosystem in its habitat. The objectives of the present study are to assess conservation status of Reptilia in Agasthyamalai Biosphere Reserve and to know the role of habitat in harbouring and conserving/protecting wild fauna. Day time opportunistic visual encounter survey method was employed to study and site different species of Reptiles. There are about 78 species of reptiles inhabited in the reserve, out of which 15 species are threatened as per IUCN, 2023 The reserve harbors three species of turtle and tortoises, 31 species of lizards under five families and 44 species of snakes under six families. There are about 37 species of reptiles which are endemic in the region comprises one species of Geoemydidae, six species of Gekkonidae, eight species of Agamidae, two species of Scincidae, seven species of Uropeltidae, eight species of Colubridae, one species of Pareidae, one species of Elapidae and three species of Viperidae.

On three species of the genus Habrocestum Simon, 1876 (Araneae: Salticidae: Hasariini) from India

Two new species of the ground-dwelling jumping spider genus Habrocestum Simon, 1876 from the wet evergreen forests of the southern Western Ghats, India are described: H. benjamin sp. nov. (♂♀) and H. swaminathan sp. nov. (♂♀). Furthermore, H. emanasakgrensis Kadam & Tripathi, 2023 is synonymized with Chinattus validus (Xie, Peng & Kim, 1993) syn. nov.. Diagnoses, digital illustrations, morphological descriptions, natural history notes and discussion are provided.

The socio-ecological impacts of tourism development in the Western Ghats: the case of Wayanad, India

Globally, tourism is advocated as a development tool with the potential to uplift socioeconomic conditions for marginalized populations and contribute to biodiversity conservation. The expectation is that the tourism model of development can bring about positive social changes in diverse communities by broadening livelihood opportunities and concurrently preserving crucial ecosystems, which are regarded as valuable assets in the tourism sector. We investigated Wayanad in the Western Ghats of India, challenging the notion of “tourism for development.” We examined the socio-ecological features of the region, the evolution of tourism and sustainable tourism, and the implications across various sectors. The research employed an empirical approach grounded in the critical examination of socio-ecological systems for tourism governance and sustainability. The data were obtained through in-depth interviews conducted in Wayanad and a review of the relevant literature. The results reveal that despite the prevalent and persuasive arguments favoring tourism, there are extensive multi-sectoral implications in tourism development that negatively affect both the environment and people at large. These impacts include the erosion of agrobiodiversity-linked traditional Adivasi lifestyles, the displacement of local communities, the encroachment of tourism projects into forests and increased human–animal conflicts, the absence of social security measures for marginalized communities, a decline in traditional livelihood options, and an overreliance on the tourism industry and the private sector. These discernible impacts have pushed the fragile region further into a socio-ecological imbalance. Tourism development in ecologically delicate areas should take into account socio-ecological impacts because a region's culture and nature are key components of its attractiveness as a tourist destination. Large-scale landscape planning should involve the perspectives of various stakeholders, including both direct and indirect participants who could be influenced by tourism. The marginalization of Adivasi communities that maintain the region's ecological integrity is unproductive for both the economic and regional development interests of tourism.

Exploring the impact of land use change on soil quality under different ecosystems – a case study in the Nilgiri Hill region of Western Ghats global biodiversity hotspot

Exploring the impact of land use change on soil quality under different ecosystems – a case study in the Nilgiri Hill region of Western Ghats global biodiversity hotspot

Accuracy of historical precipitation from CMIP6 global climate models under diversified climatic features over India

The importance of global climate models (GCMs) is increasingly recognized due to their excellent ability to accurately predict climatic factors. These capabilities prove invaluable to water resources engineers as they facilitate effective planning and strategic decision-making. Finally, evaluating the performance of GCMs is very important because it allows us to simulate and predict different climate scenarios, empowering us to make informed choices. Therefore, the purpose of this study is to determine the degree of discordance between historical simulated data produced by the CMIP6 models and historical observational data over different climate zones of India. The ability of 24 different GCMs to reproduce the geographical and seasonal distribution of Indian precipitation has been tested by analyzing the daily historical precipitation forecasts from these models. These models have been used to estimate the degree of uncertainty associated with the spatiotemporal variability of precipitation forecasts. More than 20% percent bias (PBIAS) is observed to occur predominantly in four climate classifications: polar tundra, temperate, cold, and tropical monsoon. In some regions of India, the CMIP6 models produce overestimated or underestimated results. The locations identified indicate that there have been changes of more than 20% PBIAS near Sivalik Range, Naga Hills, and Western Ghats. The precipitations of those regions that have been underestimated also imply that those locations have different climatic conditions. This study also highlights that CMIP6 GCMs are yet to produce better results near several Indian mountainous regions depending upon climates. The outcomes of this study will be very useful for reconstructing modeled data for that specific regions.

A holistic approach of remote sensing, GIS, and machine learning for shallow landslide susceptibility mapping in Gaganbawada region of Western Ghats, India

A holistic approach of remote sensing, GIS, and machine learning for shallow landslide susceptibility mapping in Gaganbawada region of Western Ghats, India

Nutrient Dynamics in Small West-Flowing Tropical Mountainous Rivers of India

In this study, the distribution of dissolved inorganic nitrogen (DIN), phosphorus (DIP), and silicate (DSi) in surface waters of 70 coastal rivers in India's Western Ghats (WG) has been determined. The nutrient concentrations in individual rivers appear to be influenced by catchment geology, land use, and climate. The entire WG region contributes 0.31 Tg of DIN, 0.03 Tg of DIP, and 5.65 Tg of DSi annually to the coastal Arabian Sea. The annual ratios of N:P, Si:N, and Si:P suggest that most of these rivers are limited by P rather than N, and there is an excess supply of Si, primarily from natural sources. P limitation is severe during monsoon periods, while N limitation is observed in the Deccan Traps region. The annual export of 0.31 Tg of DIN from WG rivers could support 2.05 Tg of carbon (new production) on the Arabian Sea coast, indicating that the riverine export of DIN can significantly remove atmospheric CO2 through biological pumps in the Arabian Sea. The study also confirms that the excess input of Si from natural processes relative to the anthropogenic supply of limited P and N further supports the idea that riverine nutrient inputs from small west-flowing tropical mountainous rivers do not contribute to coastal eutrophication along the Eastern Arabian Sea coast.

New Indian species of Dacus Fabricius (Diptera: Tephritidae: Dacinae: Dacini) similar to Dacus crabroniformis (Bezzi), endemic to the Western Ghats and Northeastern Himalayas

Two new species of Dacus Fabricius, namely D. (Mellesis) nagarathnae Abhishek, David & Hancock, sp. nov., from Meghalaya and D. (Mellesis) venkateshi Abhishek & David, sp. nov., from the Western Ghats of India are described and illustrated. The Nepalese D. (Callantra) succaelestis Ito is newly synonymized with D. (Mellesis) polistiformis (Senior-White). An updated illustrated key to the 22 species of Dacus now known from the Indian Subcontinent is provided and attractant responses are listed.

Complete mitochondrial genome of critically endangered catfish Hemibagrus punctatus (Jerdon, 1849) and comparative analysis for insights into the phylogeny of hemibagrids through mitogenomic approach.

Hemibagrus punctatus (Jerdon, 1849) is a critically endangered bagrid catfish endemic to the Western Ghats of India, whose population is declining due to anthropogenic activities. The current study aims to compare the mitogenome of H. punctatus with that of other Bagrid catfishes and provide insights into their evolutionary relationships. Samples were collected from Hemmige Karnataka, India. In the present study, the mitogenome of H. punctatus was successfully assembled, and its phylogenetic relationships with other Bagridae species were studied. The total genomic DNA of samples was extracted following the phenol-chloroform isoamyl alcohol method. Samples were sequenced, and the Illumina paired-end reads were assembled to a contig length of 16,517bp. The mitochondrial genome was annotated using MitoFish and MitoAnnotator (Iwasaki et al., 2013). A robust phylogenetic analysis employing NJ (Maximum composite likelihood) and ASAP methods supports the classification of H. punctatus within the Bagridae family, which validates the taxonomic status of this species. In conclusion, this research enriches our understanding of H. punctatus mitogenome, shedding light on its evolutionary dynamics within the Bagridae family and contributing to the broader knowledge of mitochondrial genes in the context of evolutionary biology. The study's findings contribute to a better understanding of the mitogenome of H. punctatus and provide insights into the evolutionary relationships within other Hemibagrids.

Optimizing callus formation in the endangered medicinal tree Hydnocarpus macrocarpa using phytohormone

Hydnocarpus macrocarpa (Flacourtiaceae) is one of the endemic and endangered medicinal tree, was selected to investigate the influence of plant growth regulators on callus formation. H. macrocarpa is majorly distributed at low and medium elevations of the Southern Western Ghats. The seeds of this plant are used for the treatment of ulcers, biliousness, leprosy and epilepsy. An experiment was carried out with two different methods. In the first method Murashige and Skoog (MS) medium supplemented with cytokinin alone or combined with auxin (2–4-Dichlorophenoxy acetic acid; Naphthalene acetic acid; Indole acetic acid; Indole butyric acid and Gibberellic acid) at different concentrations (1, 2, 3, 4 and 5 µM) were used; in the seond method, MS medium supplemented with coconut endosperm (Solid and liquid) extract (1, 2, 3, 4 and 5 %) with Aloe vera jelly extract at different concentrations (1, 2, 3, 4 and 5 %) in combination and separately were used. Among the different treatments, good callus proliferation was obtained using MS medium supplemented with Benzylaminopurine and in combination with Naphthalene acetic acid and 2–4-Dichlorophenoxyacetic acid (3 µM and 4 µM). But the best callus proliferation, shoot tip proliferation; auxiliary root and shoot formation were observed in MS medium supplemented with Aloe vera jelly extract in combination with coconut endosperm extract. The natural growth regulators supplemented with the media gave a positive response for plant growth. The results showed that the natural growth regulators, such as coconut endosperm and Aloe vera jelly extracts were found to be more efficient than the synthetic growth regulators (auxin and cytokinin). The presence of Indole acetic acid and Indole butyric acid in both Aloe vera jelly extracts and coconut endosperm were confirmed by High performance liquid chromatography and Fourier transform infrared spectroscopy analysis.

First Record of Garra triangularish from Madhya Pradesh, India

Garra triangularis Shangningam et al. [1] has been reported first from the Sakartod River at Khanvel, Dadra & Nagar Haveli (UT), Western ghats, and then from Gajapati district of Odisha, Eastern Ghat. The present study reports it for the first time from Madhya Pradesh. The present specimen agrees with all the morphometric and meristic counts of the species, including the snout shape and the structure of tubercles on the proboscis. G. triangularis has a new distribution record from the State of Madhya Pradesh in India.

Emblica chakrabartyi sp. nov. (Phyllanthaceae), a striking species from the southern Western Ghats, India

A new species of Emblica Gaertn. (Phyllanthaceae), E. chakrabartyi sp. nov. from the southern part of the Western Ghats, India is described here along with data on distribution, phenology and colour photographs. A key to the species of Emblica in India is also provided. The new species is allied to Emblica anamalayana, but differs in habit, urceolate staminate flowers with short pedicel, inner tepals of staminate flower larger than outer, short anthers which are equal in length to its column, three distinct deeply bifid styles, shape of capsule and its styles and black lineolate smooth seeds.

Identifying Climatic Niche Shift of The Endemic Avifauna of Western Ghats

Identifying Climatic Niche Shift of The Endemic Avifauna of Western Ghats

Morphological and molecular description of a new species of sandfly, Sergentomyia (Neophlebotomus) ashwanii sp. nov. (Diptera: Psychodidae) from Western Ghats, India

Objective: To report a new species of sandfly, Sergentomyia (Neophlebotomus) ashwanii sp. nov. (Diptera: Psychodidae) from Western Ghats, India. Methods: A systematic sandfly survey was conducted in the Thrissur and Kollam districts of Kerala, India using mechanical aspirators, light and sticky traps, both indoor and outdoor habitats, for a period of one year. Deoxyribonucleic acid barcoding of samples was performed targeting mitochondrial cytochrome oxidase I (COI) gene and sequence generated was subjected to phylogenetic analysis. Results: Sergentomyia (Neophlebotomus) ashwanii, a new sandfly species is recorded and described in this communication. A single row of 10-12 pointed teeth in the cibarium with 4-6 small denticles or fore-teeth are the key characteristics that is distinctive from other members of the subgenus Neophlebotomus. Mitochondrial COI barcode followed by phylogenetic analysis of the nucleotide sequence confirms that specimens of the species belong to the same taxonomic group while the genetic distance (14.2%) with the congeners established it to be a different species. Conclusions: The Western Ghats' being an important biodiversity hotspot and has dearth of systematic entomological surveys on sandflies. The current study tried to fill the void and also report a new sandfly species.

A trait‐based understanding of the vulnerability of a Paleotropical moth community to predation by a sympatric bat with flexible foraging strategies

Abstract Prey vulnerability across seasons can be predicted by measuring their morphological traits and availability. Although conventional prey–predator dynamics focus on pairs of prey and predator species, the trait‐based approach allows us to draw inferences at the scale of the entire assemblage. Here, we coupled measurable prey traits with their availability in the study area, to identify the vulnerability of a diverse moth assemblage to predation by the lesser false vampire bat (Megaderma spasma) Chiroptera: Megadermatidae, Linneaus 1758, a bat with flexible foraging strategies, in the Western Ghats biodiversity hotspot of India. We analysed the discarded prey remains from several roosts, collected over 3 years, for seasonal patterns in the diet and selective hunting. Through light‐trapping, we collected moth specimens in different seasons and measured the morphological traits likely to affect their vulnerability to predation, such as body size and evasive flight capability. Our results showed that consumed moth prey diversity varies seasonally, with moths belonging to the Hepialidae family being preferred in the wet season. We found that the larger moth species with lower evasive capabilities are more vulnerable to predation. Sphingid and Hepialid moths, among the most abundant in the diet, have the lowest manoeuvrability and the maximum body size, respectively. By assessing vulnerability at the prey assemblage level, our study sets the stage for future research on moth–bat interactions from the diverse and less‐explored Paleotropical communities. In addition, the study reiterates the usefulness of trait‐based approaches to understanding prey–predator dynamics.

New distribution record of Alstonia sebusii (Van Heurck & Müll. Arg.) Monach. from Manipur, India

The genus Alstonia belonging to the Apocyanaceae family is represented by 44 species distributed worldwide. In India, the taxon is represented by eight species, reported from Andaman & Nicobar Islands, Western Ghats, Eastern Ghats, western Himalaya, and northeastern regions. The present study reported the occurrence of Alstonia sebusii from Pudunamei village, Mao, a new addition to the flora of Manipur. Detailed morphological descriptions and measurements were recorded based on living plant specimens. The plant is locally called ‘Topfiira Koso Pro’ having ethno-medicinal properties and widely been used by local people of the state to treat various ailments. The plant is rare and found to occur at specific location at Pudunamei village.

Aquatic insects as bioindicators of stream water quality - a seasonal analysis on Western Ghats river, Muthirapuzha, in central Kerala, India

This study was conducted to assess the water quality of Muthirapuzha River, Idukki using aquatic insects as bioindicators. Insects were collected on a seasonal basis from February 2014 to January 2015 from 12 sampling stations. Insects were sampled using standard collection methods and were identified up to family level. A total of 3,278 individuals belonging to seven orders and 37 families were collected during the study period. The greatest number of taxa was represented by order Ephemetroptera during monsoon (27%) and post-monsoon (25%), while Diptera (22.7%) dominated the pre-monsoon season. Shannon Weiner diversity index, Simpson dominance index, and Margalef’s richness index was highest post-monsoon. The EPT score in Muthirapuzha was for normal waters, however, pre-monsoon values were lowest, indicating pollution load during this period. Hilsenhoff’s family biotic index (HFBI) was used to estimate the status of organic pollution along the river based on representative families of aquatic entomofauna; values were highest at pre-monsoon season. The overall organic water quality level in the Muthirapuzha was good to fair based on this study.

Uniyala multibracteata (Gamble) H.Rob. & Skvarla (Asteraceae: Vernoniae): notes on its identity and rediscovery

The genus Uniyala H.Rob. & Skvarla with 11 species got segregated from the genus Vernonia Scherb. All 11 species are distributed in India and Sri Lanka. In India, nine species of this genus are endemic to southern Western Ghats. During our recent floristic exploration in southern India, specimens of Uniyala were collected and one of them was identified as Uniyala multibracteata (Gamble) H.Rob. & Skvarla. In further analysis, it was found that this taxon was not reported after its type collection and it was assessed as an ‘Endangered’ species (Sasidharan 2004). Hence, it is now reported as the rediscovery of the species with a note on the correct identity of the species.