Largest known madtsoiid snake from warm Eocene period of India suggests intercontinental Gondwana dispersal.

Here we report the discovery of fossils representing partial vertebral column of a giant madtsoiid snake from an early Middle Eocene (Lutetian, ~ 47 Ma) lignite-bearing succession in Kutch, western India. The estimated body length of ~ 11-15 m makes this new taxon (Vasuki indicus gen et sp. nov.) the largest known madtsoiid snake, which thrived during a warm geological interval with average temperatures estimated at ~ 28 °C. Phylogenetically, Vasuki forms a distinct clade with the Indian Late Cretaceous taxon Madtsoia pisdurensis and the North African Late Eocene Gigantophis garstini. Biogeographic considerations, seen in conjunction with its inter-relationship with other Indian and North African madtsoiids, suggest that Vasuki represents a relic lineage that originated in India. Subsequent India-Asia collision at ~ 50 Ma led to intercontinental dispersal of this lineage from the subcontinent into North Africa through southern Eurasia.

Fossils of the oldest diplodocoid dinosaur suggest India was a major centre for neosauropod radiation.

The Early Jurassic and Cretaceous deposits of India are known for their diverse sauropod fauna, while little is known from the Middle and Late Jurassic. Here we report the first ever remains of a dicraeosaurid sauropod from India, Tharosaurus indicus gen. et sp. nov., from the Middle Jurassic (early-middle Bathonian) strata of Jaisalmer Basin, western India. Known from elements of the axial skeleton, the new taxon is phylogenetically among the earlier-diverging dicraeosaurids, and its stratigraphic age makes it the earliest known diplodocoid globally. Palaeobiogeographic considerations of Tharosaurus, seen in conjunction with the other Indian Jurassic sauropods, suggest that the new Indian taxon is a relic of a lineage that originated in India and underwent rapid dispersal across the rest of Pangaea. Here we emphasize the importance of Gondwanan India in tracing the origin and early evolutionary history of neosauropod dinosaurs.

Avifauna habitability of wetlands in an intensive cultural landscape: insights from the Ichhamati floodplains, India.

Wetlands of Ichhamati floodplains, India, are endowed repositories of native and migratory avifauna. However, unplanned utilization and unregulated resource extractions had led to the continual ecological deterioration of these wetland habitats. Considering avifauna habitability as an environmental manifestation of wetland health, the present study attempted to assess the habitability status of major 18 wetlands (> 10 ha) of the floodplains under different livelihood dependency patterns. Accordingly, six widely used ecological indicators of avifauna distribution, species composition, and abundance had been applied to construct a composite index of avifauna habitability for two phases, viz. 2012-2013 and 2017-2018. Results indicated that wetlands with mixed livelihood practices (average habitability index score 2.471) were having statistically significant (p < 0.001) better habitability than those with agriculture and fishing dominated livelihood patterns (average index score 0.378 and - 2.746 respectively) in 2012-2013. The same scenario prevailed in 2017-2018 although overall wetland habitability was found to be declining throughout the floodplains during this period, especially in agriculture dominated wetlands (average index score 0.185). Faulty implementation of rural employment generation programs and distance cum lesser connectivity of wetlands with the perennial river channel had been identified as the prime detrimental factors of this degeneration and consequent loss of avifauna diversity.

Analyzing the effects of afforestation on estuarine environment of river Subarnarekha, India using geospatial technologies and participatory appraisals.

In the Subarnarekha estuary of eastern India, deforestation remained a perpetual menace throughout the last century, thereby considerably augmenting the regional environmental vulnerability, especially in the wake of climate change-induced rise of sea levels. Like other similar areas, coastal afforestation had been widely implemented here as a prime measure of integrated coastal zone management. This study highlighted the impacts of such afforestation initiatives conducted in this area during the last 40 years by integrating geospatial information and community feedbacks. It was also a pioneering one in evaluating the level of sustainability achieved by these initiatives chiefly by analyzing their ability to attain the dual aims of environmental conservation and livelihood generation for the coastal communities. Results indicated that the detrimental effects of the continual removal of healthy mangrove and Pandanus tectorius stands could overwhelmingly be traced along the backshore areas and riverbanks. However, the scenario became better since 2008-2009 as both the dense mangroves and Casuarina plantations had experienced considerable areal increases primarily due to the renewed impetus on the Joint Forest Management and Social Forestry programs as well as regulation on shrimp aquaculture practices. Conversely, overall status of biodiversity and ecological composure remained alarmingly poor as many areas exhibited monospecific stands of Avicennia species. Accordingly, the study suggested establishment of appropriate zonal plantations based on species assemblage and utilities, bio-stabilization of coastal dunes, regulated grazing, enhanced community emancipation regarding usufruct sharing, and conflict resolution as the imperative measures for sustainable ecological restoration of this estuary.

An alternative approach for estimating above ground biomass using Resourcesat-2 satellite data and artificial neural network in Bundelkhand region of India.

Determination of above ground biomass (AGB) of any forest is a longstanding scientific endeavor, which helps to estimate net primary productivity, carbon stock and other biophysical parameters of that forest. With advancement of geospatial technology in last few decades, AGB estimation now can be done using space-borne and airborne remotely sensed data. It is a well-established, time saving and cost effective technique with high precision and is frequently applied by the scientific community. It involves development of allometric equations based on correlations of ground-based forest biomass measurements with vegetation indices derived from remotely sensed data. However, selection of the best-fit and explanatory models of biomass estimation often becomes a difficult proposition with respect to the image data resolution (spatial and spectral) as well as the sensor platform position in space. Using Resourcesat-2 satellite data and Normalized Difference Vegetation Index (NDVI), this pilot scale study compared traditional linear and nonlinear models with an artificial intelligence-based non-parametric technique, i.e. artificial neural network (ANN) for formulation of the best-fit model to determine AGB of forest of the Bundelkhand region of India. The results confirmed the superiority of ANN over other models in terms of several statistical significance and reliability assessment measures. Accordingly, this study proposed the use of ANN instead of traditional models for determination of AGB and other bio-physical parameters of any dry deciduous forest of tropical sub-humid or semi-arid area. In addition, large numbers of sampling sites with different quadrant sizes for trees, shrubs, and herbs as well as application of LiDAR data as predictor variable were recommended for very high precision modelling in ANN for a large scale study.

An alternative approach for delineating eco-sensitive zones around a wildlife sanctuary applying geospatial techniques.

The dynamics, degradation, and conservation of forest ecosystems are matters of prime concerns worldwide at the present. Proper planning and management of a forest area are essentially needed to protect it from the grasp of burgeoning pressure of urban-industrial sprawl. Establishment of eco-sensitive zones (ESZs), which act as buffer areas around the core forests, is one of the key approaches towards achieving this goal. This paper deals with the applicability of geospatial techniques to identify the ESZ around an Indian wildlife sanctuary following the different rules and acts prescribed by the Government of India. Gumti Wildlife Sanctuary, located in the northeastern state of Tripura in India, has been selected here as a case study. Collected pieces of information on the distribution of biodiversity and human population in the area were also used to make the approach more holistic. As inferred from this study, remote sensing and geographical information systems were found to be easily implementable and time as well as cost-effective tools for this purpose with a distinct advantage of spatial as well as temporal accuracy in identifying the existing land use and land cover patterns in pilot assessments. However, the results indicated that only appropriate hybridization of field-based information on the biodiversity and ecological aspects of the forest as well as patterns of human interferences with the remote sensing and GIS-based data could make this approach more relevant in actual implementations.

Community based mangrove management: a review on status and sustainability.

Community Based Mangrove Management (CBMM) has been advocated by both academia and governing agencies as a viable alternative for sustainably managing the ecologically important mangrove forests which are disappearing rapidly worldwide. Drawing insights from diverse sustainability issues, capabilities and performances of worldwide CBMM initiatives were examined in this paper. Higher numbers of CBMM initiatives were reported from South Asia and lesser from South America and Africa. Identification of the causes of degradation at a site and use-specific zonal replantations with respect to species associations were identified as major criteria of ecological sustainability. Regarding economic sustainability, transformation of potential uses of mangroves known by local communities into actual ones was found to be necessary. Proper disbursement of accrued benefits among community members irrespective of their socio-cultural status is also a major concern. Restructuring of CBMM institutions by ensuring participation of subsistence based users in decision-making and resource sharing have been identified as a prime determinant of institutional sustainability. However, limited number of studies on socio-political and institutional aspects as well as impacts of globalization induced socio-cultural transformations of communities on CBMM had been actually found. More focused researches on these aspects had been recommended for better community management of these highly stressed forests.