Sreejith, K. A. | bioRxiv Science

bioRxiv2024

LONG-TERM ECOLOGICAL MONITORING IN INDIA: A SYNTHESIS

Long-term ecological monitoring (LTEM) is crucial for understanding ecological processes and responses to environmental change, informing management of natural resources, and biodiversity conservation. Systematic LTEM efforts began in India in the mid-1900s, but there is a lack of comprehensive synthesis of LTEM efforts in the country. Here, we use a wide-ranging questionnaire survey of ecologists coupled with a survey of published literature on LTEM efforts in India to synthesise their thematic and geographical spread, and types of data being collected, and identify key challenges to the establishment and maintenance of LTEM projects in the country. Studies monitor 77 unique subjects across 272 LTEM efforts in India. LTEM efforts are more often located in the Western Ghats and Eastern Himalaya, focused on forest vegetation, and monitoring factors such as abundance, distribution, species richness, and biomass. Regions such as North-Eastern, Eastern, Central, and North-Western India, ecosystems such as grasslands, deserts and wetlands, organisms such as macrofungi, amphibians, and reptiles (other than turtles) are underrepresented. Short turnover times of funding and permits were most frequently reported as hurdles in sustaining LTEM efforts. Data from LTEM efforts have been largely used to produce academic outputs such as journal articles, but have also found use for on-the-ground conservation efforts. Overall, this synthesis can help draw attention to the need for systematic long-term ecological monitoring, help efficient utilisation of existing long-term ecological data, identify regions, species and ecosystem components that are underrepresented in Indian LTEM efforts, foster collaborations, and serve as a starting point to address challenges in sustaining LTEM efforts in India.

ecology↗

bioRxiv2022

Importance Of Small Diameter Woody Plants And Treelet Species In Tropical Wet Evergreen Forest Of Southern Western Ghats, India

Tropical forests have long been accepted for their productivity and ecosystem services on account of their high diversity and stand structural attributes. In spite of their significance, tropical forests, and especially those of Asia, remain understudied. Until recently, most forest inventories in Asia have concentrated on trees 10 cm in diameter. Floristic composition, plant species diversity, above ground biomass, basal area and diversity were investigated across different life form and two-diameter classes in a large scale 10-ha plot, in the undisturbed tropical seasonal rain forest of Southern Western Ghats, Kerala, India. Regeneration pattern of the study area was examined by evaluating fishers alpha and IVI (Important Value Index) across three layer of vegetation (seedling, sapling, and tree). Within the plot, we recorded 25,390 woody plant species[≥] 1 cm dbh from 45 families, 91 genera, and 106 species. Plant density was 2539 woody individuals per hectare, with a basal area of 47.72 m2/ha and an above-ground biomass of 421.77 Mg/ha. By basal area, density, and frequency, the Rubiaceae, Sapotaceae, and Malvaceae families were the most important. Small-diameter trees (1 cm [≤] dbh [≤]10 cm) found to be 78 percent of the total tree population, 20.2 percent of the basal area, and 1.4 percent of the aboveground biomass. They also possessed 6 percent more diversity at the family level, 10% more diversity at the genus level, and 12% more diversity at the species level than woody individuals under 10 cm dbh.. Woody individuals of treelets life form and small-diameter classes were much more diverse and dense than the other groups, indicating that results based only on larger canopy trees and larger diameter class may be not an appropriate representation of the diversity status of a particular tropical forest type. Lower density of individuals in initial girth class indicates the vulnerability of the forest system to anthropogenic, natural disturbance and a changing climate. Reduce the minimum diameter limit down to 1 cm, in contrast to 10 cm limit used in most of the evergreen forest inventories, revealed a high density and diversity in thelower stories.

ecology↗