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The occurrence of landslides is not uncommon in the Western Ghats of Maharashtra, India. However, during the last week of July 2021, an unprecedented number of landslides due to heavy rainfall were reported in this region. To determine the cause of the large-scale landsliding, we mapped an event-based landslide inventory using high-resolution satellite imagery and identified 5012 landslides. We analysed rainfall data for the 2005–2021 period to identify the anomaly in rainfall quantity and its distribution which triggered such large number of landslides, particularly in 2021, even though heavy annual monsoonal rainfall is observed every year in this region. It is observed that the quantity of rainfall in 2021 is much lesser than that seen in most of the previous years. Analysis of antecedent rainfall for time-stamped landslides, such as Jui (2005), Malin (2014) and Taliye (2021), shows that two-day antecedent rainfall is the primary trigger of landslides in the region. An in-depth comparison of rainfall variability for all the years which recorded more rainfall than 2021 shows that the amount of two-day consecutive rainfall is significantly higher in 2021, although the cumulative seasonal rainfall is less than in preceding years. Further, this anomalously high rainfall was concentrated around the 600 m – 900 m elevation range. The probable consequence of such spatiotemporally localised heavy rainfall over higher elevations was rapid soil saturation triggering a large number of landslides in 2021. In times when the effect of climate change is visible in the form of weather extremes, the present study may aid in preparedness for response to such disasters. [ABSTRACT FROM AUTHOR]

The study of the avifaunal diversity was carried out in the Mangalore University campus, located in Dakshina Kannada District, Karnataka from 2013 to 2021, in and around the campus. A total of 150 bird species belonging to 18 orders and 56 families were recorded during the study. Out of these, the study area supports five species which are endemic to the Western Ghats. The feeding guild analysis revealed that the insectivorous group had the highest number of species (53 species). The study provides baseline data for monitoring the avifauna in the campus and demonstrates the importance of the area in bird conservation. [ABSTRACT FROM AUTHOR]

Vateria indica L. is a critically endangered tree species in South-Western Ghats of India, commercially exploited for its valuable resins. Seed recalcitrance is a major problem hindering the natural regeneration of this species and it poses a great challenge in seed storage and conservation. There was a continuous import of water from the maternal tissues to seed tissues till maturity and the seeds were released in a fully hydrated state. Differential accumulation of water has been noticed in the cotyledons and embryonal axis. There was a positive correlation between seed moisture content and rate of germination which is a character of recalcitrant seeds. The critical moisture content was found to be 40% in the axis and 23.5% in the cotyledons, below which the embryo will not germinate. Loss of germination ability as a result of desiccation was attributed to the cell membrane damage, expressed as the electrolyte leakage exceeding 0.79 μS/cm. ABA peaked in the mid embryogenesis, then dropped drastically and maintained a lower level till seed maturity. On desiccation, ABA started to increase but gradually dropped down. Both cotyledons and embryonal axis had differential ABA content but exhibited a general pattern of ABA level during embryogeny. Due to the thin seed coat/embryo ratio and low investment in the seed coat, this recalcitrant seed could not hold water as efficient as orthodox seeds. Thus, it germinated as soon as it was shed from the mother plant. On desiccation, ABA shot up and moisture content decreased along with electrolyte leakage and cell membrane damage. All these hindered germination of the seed. Thus, we can see a clear interplay between moisture content and ABA levels during embryogeny and desiccation. Since the seed biology of this species has not been well documented, the present work is mainly intended to study the dynamics of water and ABA during embryogeny and embryo drying. This study can surely contribute to the long-term storage and conservation of recalcitrant seeds which is a less explored area. [ABSTRACT FROM AUTHOR]

India ranks first in the world in terms of fatal landslides. Large vulnerable area (0.42 million km2), high population density and monsoon rainfall make India's landslide management and mitigation task difficult. Therefore, an understanding of landslide occurrences and exposure of socio-economic parameters on a national scale is essential to prioritise landslide mitigation efforts. In this paper, a database of 45,334 landslides (polygons) in India mapped by the National Remote Sensing Centre (NRSC) during the 1998–2018 period was compiled and catalogued in a WebGIS platform. High-resolution satellite data such as IRS PAN+LISS-III, Resourcesat LISS-IV Mx, Cartosat, WorldView, Pleiades and GeoEye were used to map landslides as small as 12 m2 to as big as 1,390,350 m2. GIS analysis using the landslide inventory revealed interesting results about control, exposure and pattern of landslide occurrences in India. The Northwest Himalayas contribute 66.5% of landslides in India, followed by the Northeast Himalayas (18.8%) and the Western Ghats (14.7%). The Greater Himalayan sequence consisting of high-grade metamorphic rocks has a considerable control (32%), and the Main Central Thrust is the major regional structure controlling (12%) landslides in India. In the Northeast Himalayas, the size of landslides and the slope gradient controlling landslide occurrence are less in comparison to the Northwest Himalayas and the Western Ghats. Landslides in the Western Ghats are triggered with a lesser amount of rainfall than the Himalayan regions. Exposure analysis using four key socio-economic parameters in the 145 hilly districts shows that Rudraprayag district is most affected by landslides in India. The understanding derived using the landslide database on a national scale will help to prioritise and strengthen landslide disaster risk reduction strategies in India. [ABSTRACT FROM AUTHOR]

In the Western Ghats of India, the soil properties, particularly Atterberg limits, are of relevance to the landslides. Pedogenic processes in the Western Ghats and plateaus on it are regulated by parent materials, relief (topography), organisms, climate, and time. In this study, the five major soils found within the mid-part of the Western Ghats in the Idukki district of Kerala, Southern India was analyzed for elucidating physical, chemical, and geotechnical properties (Atterberg limits) on landslides potentiality or slope failure processes. The result reveals that the highly weathered lateritic soils noted with lower KCl pH (3.6–4.6), low-cation exchange capacity (3.1 to 19.6 cmol(+) kg−1), low-effective cation exchange capacity (0.8 to 10.7 cmol(+) kg−1) and a negative ∆pH value indicate the presence of variable charge minerals such as amorphous sesquioxides. The variable ranking of random forest revealed that the soil Atterberg limits were significantly influenced by Citrate Bicarbonate Dithionite (CBD) iron, sand fractions, and organic carbon. The layer of porous sandy soils showed lower Atterberg limits due to accentuate with clay matter, whereas the illuvial layer (Bt) have noted as higher Atterberg limits that lead to potentially collapsing gullies or triggering mass movement during heavy rainfall followed by intensive runoff due to instability of soil mass within proxy of the steeply sloping surface. Soil geotechnical properties such as liquid limit, plastic limit, and plasticity index are the main characteristics that decide the slope stability and failure in various parts of the study area, whereas the soil profile morphometry has significantly associated with the occurrence of landslides with the plastic limit value between 28.01 and 40.48. It was noticed that the failed slopes have a higher value than stable slopes along with the hill-range topography, with soil particle sizes range of silt and clay (8.79 to 36.17 and 22.31 to 57.74%) with the measurement of liquid limit (40.05 to 68.4), plastic limit (24.2 to 43.94), and plasticity index (7.81 to 24.8). This indicates that the pedogenesis of the weathering profile of soils have significantly influenced the Atterberg limits that triggering slope failure or landslides along the gullies and weathered lateritic uplands. [ABSTRACT FROM AUTHOR]

A new species of Striga Lour., S. indica K. M. Prabhu, P. Jayanthi, A. Rajendran & M. Sabu is described from the Western Ghats of India. This species is shows similarities to S. barthlottii Eb. Fisch. et al., a recently described species from Morocco, but differs in unequal calyx lobes, equal bracteoles, short corolla tube, corolla colour and shape, fruit shape, stem colour, branching pattern, and presence of pubescence in various parts and host specificity. A detailed description with keys, illustrations, photographs, comparison chart and tables, conservation status and distributional details are provided. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Understanding of biodiversity on a local scale is extremely important for effective conservation measures, especially in biodiversity hotpsots hosting diverse endemic flora and fauna and subject to strong anthropogenic influences. Little is known about patterns of local biodiversity and the processes generating it in the Western Ghats biodiversity hotspot: the patterns of genetic diversity and biogeographic affinities are poorly known for most of the species from this region. We studied the genetic diversity and population structuring of an endemic frog Indirana cf beddomii, from 12 localities of Western Ghats using 15 polymorphic microsatellite loci. The genetic diversity as measured by mean expected heterozygosity ( H = 0.83) or allelic richness ( A = 10.41) was high and similar in all localities. Significant genetic differentiation (mean F = 0.075) with a strong pattern of isolation by distance (IBD) across the localities was observed. Clearest genetic discontinuities in the data corresponded to topographic gaps suggesting that apart from IBD, genetic structuring in this species is strongly influenced by habitat matrix. In general, the results provide novel insight into factors that may impact the genetic diversity and population structuring of endemic amphibians in this biodiversity hotspot. [ABSTRACT FROM AUTHOR]

The article focuses on the documentation and validation of rare endemic and threatened (RET) plants from Kanuvai, Madukkarai, and Nilgiri forests of southern Western Ghats in India. It states that Western Ghats has nearly 48% of 4000 endemic plant species. It adds that endemic plants in this region needs pragmatic conservation strategies for their effective protection.

Amphibians are rapidly declining worldwide, but recent studies have shown that their diversity may be heavily underestimated, and many new species have been recently reported from biodiversity hotspots. For successful conservation and management strategies to be implemented within such hotspots, a better understanding of the species diversity and their evolutionary relationships is required. We used three mitochondrial ( 16S, 12S and CO1) and two nuclear ( rag1 and rhodopsin) gene fragments to investigate the genetic diversity within the endemic Indirana genus from the Western Ghats biodiversity hotspot. The species diversity within Indirana was found to be much higher than previously anticipated. Instead of the expected six species within this region, our analyses identified 11 clades with high (4.2-17.1%) sequence divergence. Each of these clades is likely to represent a distinct species. Particularly pronounced polyphyly was found within Indirana beddomii, which consisted of four highly supported monophyletic clades with high genetic divergence. Similarly, Indirana diplosticta was divided into two highly divergent monophyletic clades. We also report a new candidate species within the genus from Vellarimala in Kerala, which we believe is yet to be described. Our results suggest the existence of multiple unrecognized cryptic lineages within Indirana, all of which are likely to have more narrow distribution ranges and lower abundances than the taxonomic units into which they are currently assigned. Hence, the International Union for Conservation of Nature ( IUCN) Red List statuses of Indirana frogs are likely to be in need of substantial revision, and detailed genetic studies across the Western Ghats might uncover additional new candidate species from this poorly studied endemic genus. Together with several earlier amphibian studies describing cryptic species from tropics, our results highlight the importance of proper species identification efforts before it is possible to reliably determine the IUCN conservation status of tropical amphibians described on the basis of morphological criteria. [ABSTRACT FROM AUTHOR]

Frogs of the genus Indirana belong to the endemic family Ranixalidae and are found exclusively in the Western Ghats biodiversity hotspot. Since taxonomy, biology and distribution of these frogs are still poorly understood, we conducted a comprehensive literature review of what is known on the taxonomy, morphology, life history characteristics and breeding biology of these species. Furthermore, we collected information on the geographical locations mentioned in the literature, and combined this with information from our own field surveys in order to generate detailed distribution maps for each species. Apart from serving as a useful resource for future research and conservation efforts, this review also highlights the areas where future research efforts should be focussed. [ABSTRACT FROM AUTHOR]

A new species of Amomum Roxb. from Western Ghats of Kerala is illustrated and described. Amomum nilgiricum VP.Thomas & M.Sabu, sp. nov. shows similarity with A. masticatorium Thwaites in having long drying ligule with an acuminate apex, pubescent anther and echinate capsules, but differs in clump forming habit with non-stoloniferous rhizomes, tomentose lamina beneath, long corolla tube, obovate to rhomboid labellum with clefted apex and without any colour design, emarginate anther crest and reduced staminodes. Detailed description, illustration, photographs, conservation status, and distributional details are provided. [ABSTRACT FROM AUTHOR]

Coscinium fenestratum (CF) (Gaertn.) Colebr., [Family: Menispermaceae] is an endangered species of dioecious liana found in Western Ghats of India. The present investigation aimed with systematic analytical studies on the macroscopic, microscopic examination of male and female CF flowers, various solvent extractions, accompanied by phytochemical screening through chemical tests, identification of Berberine alkaloids, antioxidant activity, and Berberine quantification by high-performance thin-layer chromatography (HPTLC) process. Two different amounts of solvents (10 ml and 20 ml) with two different time intervals, that is, 15 min and 25 min, respectively, were used for extraction. Results revealed that both flowers had their own unique characters. Chemical tests revealed the group of phytoconstituents present, especially Berberine alkaloids, in both the CF extracts. The yield and antioxidant activity for female flowers resulted higher in methanol extract than other extracts. Validated HPTLC method with good linearity of standard Berberine was established, and the estimated amount of Berberine resulted higher in methanol extract of the female flower (low detectable in male flower). Finally, it concluded that the methanol extract was better for extraction of Berberine from the female CF flower (10 ml volume with 15 min time period) which also showed higher antioxidant activity using the DPPH method. [ABSTRACT FROM AUTHOR]

Excess rainfall during August 2018 triggered numerous landslides in the Western Ghats region of India covering the states of Kerala, Karnataka and Tamil Nadu. These landslides caused widespread damage to property, loss of life and adversely affected various land resources. In this article, we present an inventory of landslide prepared from the analysis of multitemporal high-resolution images acquired before and after the rainfall event from Resourcesat-2, WorldView-2, GF-2, SPOT-6 and 7, Pleiades-1, Kompsat-3 and Sentinel-2 Earth observation satellites. A total of 6970 landslides with a cumulative area of 22.6 sq. km were mapped for this rainfall event. Majority of landslides have occurred in Kerala (5191), followed by Karnataka (993) and Tamil Nadu (606). Landslides are mostly debris slide and debris flow type with entrainment along the channels. Results show that landslides (83.2%) are triggered by very high rainfall. Also, very high rainfall has resulted in 14.9% of landslides even though slopes are moderate, mainly in the Kodagu district of Karnataka. [ABSTRACT FROM AUTHOR]