Indian monsoon variations during three contrasting climatic periods : the Holocene, Heinrich Stadial 2 and the last interglacial-glacial transition

Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here by permission of Elsevier for personal use, not for redistribution. The definitive version was published in Quaternary Science Reviews 125 (2015): 50-60, doi:10.1016/j.quascirev.2015.06.009.In contrast to the East Asian and African monsoons the Indian monsoon is still poorly documented throughout the last climatic cycle (last 135,000 years). Pollen analysis from two marine sediment cores (NGHP-01-16A and NGHP-01-19B) collected from the offshore Godavari and Mahanadi basins, both located in the Core Monsoon Zone (CMZ) reveals changes in Indian summer monsoon variability and intensity during three contrasting climatic periods: the Holocene, the Heinrich Stadial (HS) 2 and the Marine Isotopic Stage (MIS) 5/4 during the ice sheet growth transition. During the first part of the Holocene between 11,300 and 4,200 cal years BP, characterized by high insolation (minimum precession, maximum obliquity), the maximum extension of the coastal forest and mangrove reflects high monsoon rainfall. This climatic regime contrasts with that of the second phase of the Holocene, from 4,200 cal years BP to the present, marked by the development of drier vegetation in a context of low insolation (maximum precession, minimum obliquity). The historical period in India is characterized by an alternation of strong and weak monsoon centennial phases that may reflect the Medieval Climate Anomaly and the Little Ice Age, respectively. During the HS 2, a period of low insolation and extensive iceberg discharge in the North Atlantic Ocean, vegetation was dominated by grassland and dry flora indicating pronounced aridity as the result of a weak Indian summer monsoon. The MIS 5/4 glaciation, also associated with low insolation but moderate freshwater fluxes, was characterized by a weaker reduction of the Indian summer monsoon and a decrease of seasonal contrast as recorded by the expansion of dry vegetation and the development of Artemisia, respectively. Our results support model predictions suggesting that insolation changes control the long term trend of the Indian monsoon precipitation, but its millennial scale variability and intensity are instead modulated by atmospheric teleconnections to remote phenomena in the North Atlantic, Eurasia or the Indian Ocean.The work of C.Z. was supported by the ANR MONOPOL

A floristic study on herbs and climbing plants at Puducherry, South India: an approach to biodiversity conservation and regeneration through eco-restoration

A qualitative floristic exploration with life form classifications and monitoring of flowering and fruiting phenology has been carried out at a restored site near Puducherry, South India in 2009 and 2010. The species were classified into three categories based on their occurrence status, namely, Naturally Occurring, Naturally Regenerated and Introduced. The present study focuses only on two life forms, the Herbaceous and the Climbing plants. The site selected for eco-restoration originally comprised of an eroded and severely degraded landscape with scattered remnant species. However, active human intervention over a thirty year period included the introduction of appropriate plant species and other physical measures to enhance soil fertility and ground water level, and regenerate and conserve the deteriorating typical Tropical dry evergreen forest (TDEF) vegetation. A large number of naturally ccurring herbaceous, climbing species (172) and a consistent number of naturally regenerated species (44) are now observed as a result of eco-restoration. Lowland herbaceous species have also established themselves as a green cover at ground level. At present, parts of the area have fertile soils and rich floristic composition with the herbaceous life form represented by 165 species encompassed in 105 genera and 37 families, and the climbing plants represented by 68 species belonging to 54 genera and 25 families. ‘Genus to family’ and ‘species to genus’ ratios indicate the establishment of diverse vegetation in the study site. Nearly one third of the species have been observed flowering throughout the year and about half of the species were observed fruiting throughout the year. We emphasize that the two fold approach of land and vegetation reclamation has been very effective in helping restore the unique TDEF vegetation at the local level and the same may be extended to help regenerate and conserve the Coromandel Coastal vegetation at the regional scale

Study of cognitive functions in breast cancer patients: A case control study

Context: One-third of breast cancer survivors report difficulties with concentration, multi-tasking, and memory. Cognitive dysfunction can have an impact on quality of life by affecting activities of daily living, treatment compliance, interpersonal relationships, work/profession, and future. Aims: The objective of this study was to evaluate the cognitive functions in breast cancer patients. Settings and Design: This study was conducted in the outpatient department of Oncology from where the cases were recruited. The controls were patients attending other departments and not suffering from cancer. Materials and Methods: A total of 60 patients, 30 breast cancer patients and 30 non-cancer individuals patients matched for age, education were evaluated. Tools used were SMMSE, TMT-B, and DSST for evaluation of cognitive functions. Statistical Analysis: The various findings were analyzed using Chi-square test, Mann-Whitney Test, T test and ANOVA. Results: Breast cancer patients had highly statistically significant cognitive deficits in language and recall domains and significant deficit on orientation domain of SMMSE. They performed poorly in TMT-B, taking more time to complete the test which was statistically highly significant. No significant deficits were noted on the DSST test. Conclusion: Breast cancer patients show statistically significant cognitive deficits as compared to non cancer individuals

Leaf classes, foliar phenology and life forms of selected woody species from the tropical forests of central and southern Eastern Ghats, India

A checklist of selected woody species of Angiosperms is provided with the aim of classifying their life forms, foliar phenology and leaf classes from the tropical forests of central and southern Eastern Ghats, India. Though there are checklists available for the plants of the Eastern Ghats, a comprehensive listing of quantitative foliar measurements as done in other parts of the world, leading to valuable inputs for Plant Functional Type (PFT) classification, has not thus far been done for this key biogeographic zone of India. The list, gathered from 388 individual plants through the study area, encompasses 156 species and 3 infraspecific taxa which belong to 116 genera and 50 families. Of the total 159 taxa, 83 are evergreen and 76 are deciduous. 135 taxa are trees, 13 are shrubs 10 are climbing shrubs and one hemiparasite. Among the leaf classes of species, mesophyll dominated with 87 species, followed by notophyll (39), microphyll (24) and macrophyll (9). Hence, quantitative leaf trait measurements for selected woody species and the methodology for such studies in the tropics is the unique contribution of the present paper to the existing state-of-the-art

Clinical and laboratory profile of diabetic ketoacidosis in elderly with type 2 diabetes mellitus

INTRODUCTION: Diabetic ketoacidosis (DKA) in elderly is rare and poses a special problem because of high degree of mortality, comorbidity, age-related impairment of functional ability, and increased chances of hypoglycemia. OBJECTIVES: The main objective is to study the precipitating factors, clinical and laboratory profile of DKA in elderly. MATERIALS AND METHODS: A total of 100 type 2 diabetes mellitus (T2DM) patients, ≥60 years, admitted in a rural tertiary medical center were included in this study. RESULTS: Most of them had prolonged diabetes with mean duration of 7.3 ± 4.6 years. 24 patients were newly detected diabetes mellitus. Systemic infections seen in 67 patients (respiratory –32.8%, sepsis – 28.4%, acute gastroenteritis – 22.4%, and urinary tract infections– 16.4%), were the main precipitating factors, followed by noncompliance to drugs (34). Osmotic symptoms were reported by most (62) followed by pain abdomen (56). Dehydration was seen in 72 patients, whereas altered sensorium in 48. Blood glucose at presentation (493.12 ± 72.38 mg/dl) and HbA1c levels (9.63 ± 0.94%) were found to be elevated with lowered arterial pH (7.14 ± 0.07) and bicarbonate (13.7 ± 4.2 mEq/L). 22 had severe acidosis and 10 had mild acidosis. There was no mortality in the present series. CONCLUSION: DKA is more common in T2DM than anticipated. The most common precipitating factor is infection followed by noncompliance even in elderly. Majority had poor glycemic control. All elderly diabetic patients with high serum glucose level must be investigated for ketosis as the symptoms of DKA are minimal and morbidity and mortality are high in these patients

Resilience of the tropical dry evergreen forest in the human-impacted region of Coromandel Coast, India

International audienceAn assessment of the resilience of Tropical Dry Evergreen Forest(TDEF) formation was made using quantitative vegetation andsurface soil pollen surveys in 14 sites around Pondicherry withinthe heterogeneous landscape of the Coromandel coast ofsouthern India. The sites for vegetation and soil surface pollensamples were selected using a stratified random sampling.Vegetation or land cover quantities were measured in quadratswhere 325 angiosperm species representing 75 families ofAngiosperms of the present vegetation were recorded. Therelative densities of species evaluated from three distinct siteshelped to compare them across time, the trajectory of individualspecies and the TDEF itself. The vegetation study indicates thatsome of the TDEF species have the ability to ‘recover’ and adaptto changing conditions and anthropogenic pressures. The studyalso demonstrated the significance of the use of pollen toreconstruct the past land cover

Diversity matters: Diet of Apis cerana in southeast India includes one consistently occurring and several seasonally available floral sources

International audienceLittle is known about the agroecological implications of the Asian honey bee Apis cerana Fabricius in itsvast native range including southeast India. To identify the foraging preferences of this generalist species,we collected 388 corbicular pollen samples over three years at Merveille, an eco-restoration site inPuducherry region, southeast India. Pollen was collected twice or thrice weekly from March 2018 toDecember 2021 in three locations within the site. We used canonical correspondence analysis to evaluatehow average daily temperature, humidity and other meteorological changes over the years wouldinfluence A. cerana’s diet. We show that (1) A. cerana has a large dietary niche (87 pollen taxa), butessentially feeds on Cocos nucifera (all year long) and on Borassus flabellifer, Turnera, Acacia,Mollugo/Trianthema, Leucaena/Prosopis, Portulaca, Poaceae, Syzygium-t, Dodonaea viscosa and Boerhaviaseasonally; these were most frequently and abundantly foraged at all locations. (2) In all locations, beespreferentially feed on arboreal plants (44 taxa). (3) Bees’ pollen diet varies in composition according toseasons. It is also least diverse in the hottest and driest months (March-May) with 2–4 taxa against 7–13taxa in other months. (4) In 2021, which was more humid and slightly cooler than 2018 and 2019, beediet included more pollen of Cyperaceae, Dodonaea viscosa, Liliaceae and fallow land weeds such asBoerhavia and Mimosa pudica. In conclusion, corbicular pollen loads of Apis cerana provide a long andcontinuous record of the bee’s diet and its changes through time and space. The diet changed accordingto subtle changes in humidity and temperature as also drastic changes in rainfall at the study site,likely reflecting changes in the floral resource availability and the bees’ preference. The sustained presenceof this bee species within its native ranges can be a bellwether of pollinator friendly habitats

Eaux douces - eaux amères

DVD trilingue anglais, français, Tamil, de l'institut français de Pondicherry, publications hors série n°5, ISSN 0972-2157, ISBN 978-81-8470-157-