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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 impacts. Here, we examined the relationship between AGB and different predictor variables and quantitatively evaluated their relative importance in lowland to lower montane deciduous and lower montane – montane evergreen forest types. We hypothesised that the relationship between AGB and climate, topography, structural diversity, species diversity (alpha and beta) and phylogenetic diversity would differ between the two forest types. We inventoried trees from 114 plots (each 0.1 ha) and used partial least square structural equation modelling to test the direct and indirect relationship between AGB and the predictor variables. We found that structural diversity variables, stem density and tree girth, were significantly and positively related to AGB in both forest types, displaying a stronger relationship in montane evergreen forests (w = 0.65 for density and 0.89 for tree girth). In the deciduous forest, alpha and phylogenetic diversity were also important factors, whereas beta and phylogenetic diversity were important in the evergreen forest. The effects of topography and climate varied between forest types, with elevation and precipitation being related to AGB directly and indirectly through their relationship with structural diversity. Our results suggest that structural diversity is a key driver of tropical forest biomass, both directly and indirectly. This fundamental understanding can aid in the predictive efforts of biodiversity conservation and forest management. [ABSTRACT FROM AUTHOR]

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 classifying the forest. Sentinel-2 derived temporal Normalized Difference Vegetation Index (NDVI) data of 2019 was used to extract the vegetation trends and to derive phenological metrics using CropPhenology R package. Seasonal trends revealed that the highest greenness was associated with high NDVI values in September and October. We identified seven vegetation classes in the region and used Random Forest classifier to prepare a community level classification map with an overall classification accuracy of 68.9%. Our results revealed that incorporating the field sampling data and NDVI data can be effectively used for identifying, mapping and monitoring phenology of the BRT landscape.. [ABSTRACT FROM AUTHOR]

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 diverse flora and fauna with distinct ecological features. For the last four decades the sanctuary has witnessed the loss of forest cover, yet the vegetation in few locations is relatively undisturbed. The current inventory was undertaken during 2019–2020 to provide a checklist of woody species from SWS under-researched earlier. The list comprises 269 species of trees, lianas and shrubs distributed in 207 genera and 68 families. The most diverse families are Fabaceae, Moraceae, Rubiaceae, Rutaceae, Lauraceae, Apocynaceae, Meliaceae, Malvaceae, Phyllanthaceae, and Anacardiaceae, representing 48% of total woody flora. The sanctuary shelters 263 native and six exotic plant species. Thirty-nine species were endemic to the Western Ghats, five species to peninsular India and one species to the Western Ghats and Andaman & Nicobar Islands. Four forest types, i.e., dry deciduous, moist deciduous, semi-evergreen, and evergreen forests, are represented in the sanctuary. Of the total species, only seven occurred in all forest types, while 111 species are exclusive to a single forest type. One-hundred-and-four taxa were assessed for the International Union for Conservation of Nature & Natural Resources (IUCN) Red List. Ten species that fall under Near Threatened, Vulnerable, and Endangered categories were encountered occasionally. The baseline data generated on plant diversity will be useful in highlighting the importance of these forests for species conservation and forest management. Such data form a cornerstone for further research. For instance, to understand the effect of invasive species and human impacts on the diversity of the region. [ABSTRACT FROM AUTHOR]

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 information on historical forest management and fieldwork research with remote sensing vegetation monitoring methods. The study area falls within the central portion of the Indian Western Ghats, a global biodiversity hotspot. In particular, part of the analysis was performed on the Kadamakal Reserve Forest and Pushpagiri Wildlife Sanctuary, which harbours an endemic low elevation dipterocarp evergreen forest. This area was managed by selective logging and became fully protected in 1984. We performed multiple time series macroscale analyses between 1999 and 2020 on the Indian Central Western Ghats region, using satellite products at 1 km spatial resolution from the VITO Copernicus Global Land Service on Dry Matter Productivity, Fraction of Absorbed Photosynthetically Active Radiation, and Normalised Difference Vegetation Index. We also performed a very-high spatial resolution Normalised Difference Vegetation Index differential analysis between 2021 and 2016 with Sentinel 2-L2A products to investigate forest dynamics within the reserve. At the 1 km spatial resolution has been found an increase in all three vegetation indices, by employing the LOESS statistical method for the smoothed transition autoregressive model of raster data medians of our datasets. The boxplot raster distribution analysis also highlighted a significant imbalance in dry matter productivity in the last decade (2010−2020) comparing the previous one (1999–2009). The second part of the analysis, at 10 m spatial resolution within the reserve forest, revealed a growth in the vegetation cover on the top of the Pushpagiri Mountain ridge and in a previously landslide area. The study found new erosion channels down to the upper plateau on the South-West side of the reserve due to an increment of the run-off processes during the monsoon period. This satellite analysis highlighted generalised positive vegetation trends in the Central Western Ghats, India, over the last twenty-two years, enhancing an improvement in the ecosystem functioning and carbon storage ecosystem service. Notably, through this work, we also developed a standardised and open-access framework to monitor the vegetation remotely (SVIT) during periods of forest inaccessibility for fieldwork sampling. [Display omitted] • Tropical forest ecosystems are hotspots for conserving biological diversity • Natural conservation policies focus on the tropical region's legacy • Remote sensing tools as proxies for monitoring the vegetation functioning • Open-source ecology as a tool for standard methods and information consistency • Highlights of conservation effectiveness efforts in Central Western Ghats, India [ABSTRACT FROM AUTHOR]