Ayyappan Narayanan

• Dr
• Researcher at French Institute of Pondicherry

Calophyllum pascalianum, a medium sized tree occuring along the riverbanks in the southern Western Ghats of India, is described and illustrated. The species is different from the other allied species by its linear-oblong to linear-lanceolate leaves that are c. 7 times longer than broad. The population of the species in the type locality is threaten...

Within a 30-ha permanent plot of a tropical evergreen forest in the Anamalais, Indian Western Ghats, all the 13?415 trees =30?cm?gbh (belonging to 153 species) were identified and tagged during 1997–1998. This communication reports the results of tree population changes based on two annual censuses (1999 and 2000) of the plot after the initial cens...

A permanent plot of 30 ha (600 500 m2) was established for long-term ecological research on biodiversity and forest functioning in a tropical evergreen forest at Varagalaiar, Anamalais, Western Ghats. This paper gives the results of the first census of trees in the 30 ha plot. All trees 30 cm gbh were permanently tagged with sequentially numbered a...

Motivation Here, we make available a second version of the BioTIME database, which compiles records of abundance estimates for species in sample events of ecological assemblages through time. The updated version expands version 1.0 of the database by doubling the number of studies and includes substantial additional curation to the taxonomic accura...

Understanding phenological responses of tropical forest plant communities is crucial for identifying climate-induced changes in ecosystem dynamics. Monitoring phenology across diverse species in natural habitats provides cost-effective insights for conserving both species and forests. We studied tree phenology in a lowland evergreen dipterocarp for...

Trees can differ enormously in their crown architectural traits, such as the scaling relationships that link their height and crown size to their stem diameter. Yet despite the importance of crown architecture in shaping the structure and function of woody ecosystems, we lack a complete picture of what drives this incredible diversity in crown shap...

Accurate assessment of aboveground biomass (AGB) in tropical forests, particularly within a biodiversity hotspot, is vital for sustainable resource management and the preservation of ecosystems. However, estimating AGB in tropical forests is complex due to the diverse and intricate nature of vegetation, necessitating the integration of data from mu...

accurate mapping and monitoring of tropical forests aboveground biomass (aGB) is crucial to design effective carbon emission reduction strategies and improving our understanding of Earth's carbon cycle. However, existing large-scale maps of tropical forest aGB generated through combinations of Earth Observation (EO) and forest inventory data show m...

Key message The recurrent anthropogenic disturbances, poor regeneration potential, high carbon stocks, and restricted habitat suitability warrants effective conservation and restoration of two ecologically and economically important endemic tree species. Abstract Despite a growing consensus on the application of species distribution models (SDM) i...

Supplementary: A Comparative Analysis of Machine Learning Techniques for Aboveground Biomass Estimation: A case study of the Western Ghats, India

Lianas shape tropical forest species composition, structure, and dynamics. Increasing climate fluctuation and anthropogenic disturbances increase liana abundance. Despite the increasing number of liana studies in India, only a few have examined the distribu�tion and association of hosts with lianas, or liana–host interaction networks to deter�min...

This study presents a comparative investigation of the biodiversity variation of regeneration in the logged and unlogged sites in the Western Ghats. This research was carried out in selectively logged (37 years before) and unlogged compartments of the low-elevation dipterocarp forest in Uppangala. Individuals with a diameter at breast height from 1...

Background A gamut of abiotic and biotic factors is related to the amount of above-ground biomass (AGB) produced in ecosystems. Some factors have direct and others indirect relationships with AGB. Detailed analyses in tropical forests are few but much needed for better understanding the potential impacts of global change drivers and for mitigating...

Aboveground biomass (AGB) estimation is crucial for assessing forest productivity, carbon sequestration, and functional diversity. Integrating optical remote sensing data with field inventory to estimate AGB saturates at high biomass. However, transformed optical imagery is effective in tropical forest AGB estimation, especially for eliminating sat...

The study focuses on assessing the impact of changing environmental conditions on the leaf flushing phenology of 48 tree species within a tropical wet evergreen forest in Central western ghats, Karnataka, India. The investigation spans two time periods, 1993-1994 and 2021-2022, aiming to compare the leaf flushing timing and determine if there's any...

In ecologically sensitive areas like the Western Ghats, fire is largely considered to be the most significant management concern. Therefore, identifying and predicting the fire susceptible areas is crucial for managing protected area networks. In this study, we investigated the factors affecting forest fires and modelled the fire susceptibility in...

Biomass and carbon stock assessments in data-deficient plantations and identifying the factors influencing tree growth, distribution, and carbon stocks are extremely important for implementing sound silvicultural management and monitoring practices to achieve REDD+ goals. We conducted carbon stock assessments in five major plantation types in a reg...

Selective logging disrupts forests, changing their structure and species composition. Long-term monitoring helps in identifying the factors influencing it and aids in designing management plans. We conducted a quantitative re-assessment of trees ≥ 30 cm girth at breast height in four 1 ha plots in logged and two 1 ha plots in adjacent unlogged comp...

Tropical forest ecosystems are among the most essential habitats on Earth for conserving biological diversity and short-term climate regulation. For this reason, they are key areas of conservation policies in the world. In this paper, we aim to investigate the dynamics of forest cover and their changes in primary productivity by empowering informat...

The use of remote sensing for examining phenological variation in tropical forests is scarce. The major objectives of the study were to characterize the intra-annual variability of phenological cycle of the Biligiri Ranganathaswamy Temple Tiger Reserve (BRT) and the potentiality of these phenological metrices in defining species assemblages by clas...

Data capturing multiple axes of tree size and shape, such as a tree's stem diameter, height and crown size, underpin a wide range of ecological research—from developing and testing theory on forest structure and dynamics, to estimating forest carbon stocks and their uncertainties, and integrating remote sensing imagery into forest monitoring progra...

Litsea keralana Kosterm. (Lauraceae), an endemic and threatened species is newly reported from Biligiri Ranganathaswamy Temple Tiger Reserve (BRTTR), Karnataka state. Hitherto, this species is known from Kerala and Tamil Nadu of the southern Western Ghats. The present study confirms the range extension of the species to further north towards Karnat...

Forests across the globe have been exploited for resouces, and over the years the demand has increased, and forests are rather exploited instead of sustainable use. Focussed research on vegetation and forerst dynamics is necessary to preserve biodiversity and functioning of forests for sustanence of human life on Earth.This article emphasis that th...

Lantana camara, one of the major invasive alien species, affects the native biodiversity directly by occupying suitable niches or indirectly by increasing the fire risk. It has been suggested that climate change may increase the likelihood of invasion via modification of species ranges and invasibility in some regions. This study aims at providing...

When ordinating plots of tropical rain forests using stand-level structural attributes such as biomass, basal area and the number of trees in different size classes, two patterns often emerge: a gradient from poorly to highly stocked plots and high positive correlations between biomass, basal area and the number of large trees. These patterns are i...

Documenting the biodiversity of protected areas and reserve forests is important to researchers, academicians and forest departments in their efforts to establish policies to protect regional biodiversity. Shettihalli Wildlife Sanctuary (SWS) is an important protected area located in the central Western Ghats of Karnataka state known for its divers...

Documenting the biodiversity of protected areas and reserve forests is important to researchers, academicians and forest departments in their efforts to establish policies to protect regional biodiversity. Shettihalli Wildlife Sanctuary (SWS) is an important protected area located in the central Western Ghats of Karnataka state known for its divers...

The increasing spatial, spectral and temporal resolution of satellite images create a potential for producing accurate datasets on community level biodiversity and more widely, as an alternative to monitor individual species. This project is aimed to develop community level vegetation database for regional landscapes and describe vegetation charact...

• Questions. Changes in the functional composition of tree communities along resource availability gradients have received attention, but it is unclear whether or not understory and canopy guilds respond similarly to different light, biomechanical, and hydraulic constraints. • Location. An anthropically-undisturbed, old-growth wet evergreen Diptero...

I created an algorithm to processing a Multiple Time Series Analysis on Dry Matter Productivity, FAPAR and NDVI Satellite Products. I selected from 8 to 6 years of time resolution of an Indian Western Ghat Region to detect the forest changes. After I have been set the method I reproduce the model with higher Spatial Resolution Images (10m Sentinel...

The principal aim of this thesis is to investigate a method and standardize it through an algorithm, to analyze with a remote sensing approach, the vegetation properties and indices trend, as well as their dynamics connected to the forest structures. My focus is to link the classic research fieldwork with remote sensing vegetation monitoring techni...

The strong contribution of remote sensing has led to the development of the concept of the Remote Sensing enabled Essential Biodiversity Variables which represents a set of variables that can be monitored from space. This work synthesizes current state of research and technological development in use of remote sensing enabled essential biodiversity...

Wetland ecosystems hold an important part of the world’s biodiversity and are complex social-ecological systems. Aiming to understand interdependencies among their components and to define management policies, the social-ecological trajectory of Oussudu lake – a wetland of Pondicherry region in South India – was reconstructed and analysed. During t...

Aim Tree crowns determine light interception, carbon and water exchange. Thus, understanding the factors causing tree crown allometry to vary at the tree and stand level matters greatly for the development of future vegetation modelling and for the calibration of remote sensing products. Nevertheless, we know little about large‐scale variation and...

Aim: Tree crowns determine light interception, carbon and water exchange. Thus, understanding the factors causing tree crown allometry to vary at the tree and stand level matters greatly for the development of future vegetation modelling and for the calibration of remote sensing products. Nevertheless, we know little about large‐scale variation and...

Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research sp...

A lack of spatial congruence between carbon storage and biodiversity in intact forests suggests limited cobenefits of carbon‐focused policies for conserving tropical biodiversity. However, whether the same applies in tropical human‐dominated landscapes (HDLs) is unclear. In India's Western Ghats Biodiversity Hotspot, we found that while HDL forests...

Roadways are inevitable components in any human managed landscape across the world, with the sole objective to facilitate transportation. Reserve forests are not an exception to this situation. A roadway being a potential factor in influencing biodiversity, this study checks the possibility of relationship between the distance of tree communities f...

Aim Large tropical trees form the interface between ground and airborne observations, offering a unique opportunity to capture forest properties remotely and to investigate their variations on broad scales. However, despite rapid development of metrics to characterize the forest canopy from remotely sensed data, a gap remains between aerial and fie...

Aim: Large tropical trees form the interface between ground and airborne observations, offering a unique opportunity to capture forest properties remotely and to investigate their variations on broad scales. However, despite rapid development of metrics to characterize the forest canopy from remotely sensed data, a gap remains between aerial and fi...

Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time se...

Aim: Large tropical trees form the interface between ground and airborne observations, offering a unique opportunity to capture forest properties remotely and to investigate their variations on broad scales. However, despite rapid development of metrics to characterize the forest canopy from remotely sensed data, a gap remains between aerial and fi...

Aim: Large tropical trees form the interface between ground and airborne observations, offering a unique opportunity to capture forest properties remotely and to investigate their variations on broad scales. However, despite rapid development of metrics to characterize the forest canopy from remotely sensed data, a gap remains between aerial and fi...

Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time se...

Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community led open-source database of biodiversity time se...

Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time se...

The flora of Laos remains one of the least known within the Indo-Burma biodiversity hotspot. A floristic inventory was carried out in Phou Hin Poun National Biodiversity Conservation Area, an under-explored area of the Khammouane Limestone. This study provides a list of 27 taxa that are additions to the most recent country checklists. The Ebenaceae...

TreeGhatsData is a compilation of lists of tree taxa found in Western Ghats, South India: taxa for which the word "tree" appears in habit description in the book Flowering plants of the Western Ghats edited by the Tropical Botanic Garden Research Institute (TBGRI), including planted or cultivated taxa (Nayar, Beegam, and Sibi. 2014); tree taxa des...

The effects of fragmentation and overstorey tree diversity on tree regeneration were assessed in tropical rain forests of the Western Ghats, India. Ninety plots were sampled for saplings (1–5 cm diameter at breast height (dbh); 5×5-m plots) and overstorey trees (>9.55 cm dbh; 20×20-m plots) within two fragments (32 ha and 18 ha) and two continuous...

Very high spatial resolution (VHSR) optical satellite imagery has shown good potential to provide non-saturating proxies of tropical forest aboveground biomass (AGB) from the analysis of canopy texture, for instance through the Fourier Transform Textural Ordination method. Empirical case studies however showed that the relationship between Fourier...

The Western Ghats (WG), one of the main biodiversity hotspots of the world, shelter highly diverse forests in heterogeneous environments. The composition of these forests reflects a long and complex evolutionary and biogeographical history. Understanding the combined signatures of current and past biodiversity dynamics is needed to forecast the res...

Studies on the residual impact of logging on the diversity and composition of tropical forests are scarce in India. We examined the impact of selective logging on tree species richness, composition and structure prevalent after 27 years. Trees ≥ 30 cm girth at breast height were inventoried in four 1 ha plots in selectively logged patches and two 1...

Background: The Western Ghats of India contain the westernmost dipterocarp forests of Asia. However, only a few dipterocarp tree species actually coexist in the forest canopy among which Vateria indica and Dipterocarpus indicus are the most common. The mechanisms contributing to the coexistence of these phylogenetically closely related species have...

In a survey of endophytic fungi associated with endemic plant Cinnamomum malabatrum leaves harbored a bioactive endophytic isolate CMS 3 was identified as Colletotrichum gloeosporioides through morphological and phylogenetic analysis based on ITS-rDNA. The ethyl acetate extract of fermentation broth of Colletotrichum gloeosporioides CMS 3 displayed...

Growing pressures on mangroves throughout the world, highlight the need for studies of vegetation across spatio-temporal scales even in relict patches for ecosystem conservation. Mangroves experience human pressure due to coastal development and are also subjected to environmental stress such as cyclones, tsunami, floods, and sea-level rise, often...

Google apps to identify the tree species in the evergreen forests of the Western Ghats Download link: https://play.google.com/store/apps/details?id=com.ifp.biotik&hl=en OR in iTunes https://itunes.apple.com/fj/app/western-ghats-tree-id-biotik/id1085561257?mt=8

The present study was aimed to investigate the diversity and functional traits of lianas in four tropical forest types of peninsular India. The work also intended to study the variation in the proportion of lianas with trees along an altitudinal gradient and to compare the functional traits of lianas and trees sharing similar environmental conditio...

Lianas are woody climbers rooted in soil and are incapable of autonomous vertical growth above a certain height and rely on external support to reach forest canopy (Wyka et al. 2013). Lianas have long attracted the interest of botanists because of the peculiar characteristics associated with this life-form including their climbing mechanisms (Darwi...

This chapter describes variation in species composition, density, climbing mechanisms and dispersal syndromes of lianas across four principal forest types of peninsular India. The forest types include: wet evergreen forest (WEF), semi-evergreen forest (SEF), seasonal dry forest (SDF), and dry evergreen forest (DEF). The chapter compares the charact...

Medicinal plants are a world treasure to be natured for the benefit of mankind. About 85% of the world's population depends on traditional medical treatments based on plants remedies and ~ 25% of the world's pharmaceutical medicines are derived from plants. The resurgence of public interest in plant-based medicine coupled with rapid expansion of ph...

Online Interactive, multientry species identification tool for trees of evergreen forests in the Western Ghats Google apps to identify the tree species in the evergreen forests of the Western Ghats Download link: https://play.google.com/store/apps/details?id=com.ifp.biotik&hl=en OR LINK: for online version Follow the link http://www.ifpindia.org/d...

The genus Memecylon L. has a paleotropical distribution, with about 300 species in the World, and about 30 in India. In this note we report the distribution extension of Memecylon macrocarpum Thwaites based on our diversity inventories in tropical evergreen forests at Uppangala in the Western Ghats, India. Additional distribution records of the spe...

We provide a data set on demography of trees monitored over 20 years in Uppangala permanent sample plot (UPSP) in undisturbed, old-growth wet evergreen Dipterocarp forest located within the Pushpagiri Wildlife Sanctuary in India's Western Ghats biodiversity hotspot. During 1989—1990, all trees ≥30 cm girth at breast height (gbh) were sampled in fiv...

Changes in tree, liana, and understory plant diversity and community composition in five tropical rain forest fragments varying in area (18–2600 ha) and disturbance levels were studied on the Valparai plateau, Western Ghats. Systematic sampling using small quadrats (totaling 4 ha for trees and lianas, 0.16 ha for understory plants) enumerated 312 s...

The diversity, density, basal area, population structure and spatial distribution of all dipterocarps (≥ 10 cm dbh) was investigated in a 30-ha permanent plot of tropical evergreen forest at Varagalaiar, Anamalais, Western Ghats, south India. Dipterocarpaceae in our site was represented by three species, Dipterocarpus indicus, Hopea parviflora and...

Alpha diversity of a tree community spectrum was analyzed by hectares to address the extent of variation in tree diversity between thirty adjacent 1-ha subplots within a 30-ha permanent plot of tropical evergreen forest at Varagalaiar, Anamalais, Western Ghats, India. Three pairs of adjacent subplors had an equal number of species and for one pair...