A.P. Thomas

A.P. Thomas

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73
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Publications

Publications (73)
Article
Full-text available
The genus Moniligaster Perrier, 1872 is restricted to the Western Ghats mountain regions of the southern Peninsular India. A new species, Moniligaster julkai Narayanan & Paliwal, sp. nov., is described and illustrated using samples found in the Kerala districts of Kottayam and Pathanamthitta. Apart from that, the status of Moniligaster deshayesi mi...
Article
The present study aimed to assess the role of homegarden (HG) in safeguarding the tree diversity and carbon (C) density or storage in the Thodupuza urban region of Idukki district in Kerala, India. A stratified random approach was used for selecting the four homegardens (HGs) with a size of 1hectare (ha). The study mainly focused on species richnes...
Article
The role of multi-heavy metal tolerant bacteria isolated from the rhizosphere of Eichhornia crassipes in the phytoremediation of Cu and Pb under laboratory conditions was investigated. The heavy metal tolerant rhizosphere bacteria were identified as Bacillus cereus, Paenibacillus alvei, Aeromonas caviae, Paenibacillus taiwanensis, and Achromobacter...
Article
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A comprehensive checklist of the earthworm species known from Sri Lanka, an island country in the Indian subcontinent, is presented. In total, 81 species and subspecies belonging to 20 genera and 8 families are recorded. Of these, 58 are Sri Lanka endemics, 2 near endemics and 21 exotics. The checklist includes the type locality, any significant su...
Article
Three new species of Moniligaster Perrier, 1872, namely M. bahli Narayanan & Julka, sp. nov., M. blakemorei Narayanan & Julka, sp. nov. and M. keralensis Narayanan & Julka, sp. nov. are described from materials collected from the Indian state of Kerala. Moniligaster cernosvitovi Gates, 1962, Moniligaster horsti Gates, 1940, Moniligaster michaelseni...
Chapter
In India, Western Ghats and the west coast plains are the areas with highest diversity of oligochaete fauna, especially of the earthworms. Here we provide the first comprehensive checklist of the oligochaetes of this hottest biological hotspot of the world. In total, 322 species/subspecies belonging to 82 genera and 13 families are reported. Of the...
Article
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Over the past four decades the Western Ghats of India, one of the eight hottest hotspots of biological diversity in the world, witnessed the transformation of its prime forests into other land-use types, mainly monoculture plantations. The present study evaluated the impact of conversion of natural forests to mixed-species (teak) and monoculture (r...
Article
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Among the 102 species of earthworms known from Kerala, Dichogaster saliens (Beddard, 1893) of the Family Benhamiidae and Metaphire posthuma (Vaillant, 1868) of the Family Megascolecidae were not recorded till date. The presence of exotic earthworms D. saliens and M. posthuma are documented herewith for the first time from Kerala, based on specimens...
Article
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The potential of biochar derived from pyrolysis of Phragmites karka—an invasive wetland plant biomass—for the adsorption of methylene blue (MB) dye from the aqueous medium was studied. The physico-chemical properties of the resultant char were studied using SEM-EDS, FTIR, TGA, ICP-MS, and Brunauer–Emmett–Teller (BET). Batch adsorption experiments w...
Article
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Earthworms are known to modify the soil structure and alter the physico-chemical as well as biological regimes of the inhabiting soil. Numerous studies focussing on the role earthworms play in soil carbon (C) mineralization and stabilization have been conducted, with recent reviews portraying earthworms as greenhouse-gas emitters. The present work...
Article
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The occurrence of the exotic earthworm species Metaphire bahli (Gates, 1945) of the family Megascolecidae is recorded for the first time from India. Specimens were collected from the Alappuzha District of Kerala State. Its detailed description along with geographical distribution is provided.
Article
Full-text available
A study was carried out to find out the relationship between soil respiration (SR) rate and various environmental factors in four selected land use systems-natural forest (NF), teak (TP), rubber (RP) and eucalyptus (EP) plantations in the Western Ghats area of Kollam district, Kerala, India during three seasons in 2018. The environmental factors co...
Article
Full-text available
This is a reporting on the occurrence of little known species of earthworm Megascolex lawsoni (Bourne, 1886), of the Family Megascolecidae for the first time from the political boundary of the State of Kerala. Specimens were collected from 12 locations within Wayanad District. So far, they have been reported from neighbouring states of Tamil Nadu a...
Article
Full-text available
ABSTRACT This is a report on the occurrence of little known species of earthworm Megascolex lawsoni (Bourne, 1886), of the Family Megascolecidae for the first time from the political boundary of the State of Kerala. Specimens were collected from 12 locations within Wayanad District. So far, they have been reported from neighbouring states of Tamil...
Article
Until now, occurrence of 98 earthworm species has been reported from the Western Ghats biodiversity hotspot of Kerala. Most of the known species were recorded more than 80–90 years ago. A recent survey of the earthworms of the state has revealed the presence of two more species, namely Octolasion tyrtaeum (Savigny, 1826) and Mallehulla indica Julka...
Article
Until now, occurrence of 98 earthworm species has been reported from the Western Ghats biodiversity hotspot of Kerala. Most of the known species were recorded more than 80–90 years ago. A recent survey of the earthworms of the state has revealed the presence two more species, namely Octolasion tyrtaeum (Savigny, 1826) and Mallehulla indica Julka &...
Preprint
Full-text available
The occurrence of the exotic earthworm species Metaphire bahli (Gates, 1945) of the family Megascolecidae is recorded for the first time from India. Specimens were collected from the Alappuzha District of Kerala State. Its detailed description along with geographical distribution is provided.
Conference Paper
Full-text available
Soil health status of three land use systems in a part of Achenkovil watershed, Kerala, India
Article
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United Nations Framework Convention on Climate Change highlights the significance of carbon storage and emission in forests towards climate change mitigation. The aim of this study was to quantify the tree biomass and carbon density (carbon storage) in the tropical dry forest of the Chinnar Wildlife Sanctuary of Kerala located in the Southern Weste...
Article
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Sustainability is considered as a remedy for the environmental issues arising due to overconsumption of natural resources. In this context, the general household consumption pattern in India and—one of its states—Kerala has been studied for a period of 50 years. Generally Monthly Per capita Consumer Expenditure (MPCE) is linked with consumption, di...
Article
Full-text available
A checklist of earthworm species hitherto known from Kerala, a constituent of the Western Ghats biodiversity hotspot in India, is presented. In total, 88 species and subspecies are recorded, of which 55 are Kerala endemics, 9 near endemics, 14 exotics and 10 native peregrines. These belong to 26 genera and 9 families. The checklist includes the lit...
Article
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Two exotic species of earthworms, Amynthas alexandri (Beddard, 1900) and Metaphire peguana (Rosa, 1890) are recorded for the first time from the state of Kerala, southern India. Both the species were collected along with other exotic species at most of the sites.
Article
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Pontoscolex corethrurus (Müller, 1857) is an important peregrine earthworm species in the humid tropics and is found in land disturbed by human activities. Its presence in Kerala state was first reported by Michaelsen in 1910. So far the occurrence of 14 exotic earthworm species has been reported from Kerala state. However present distribution stat...
Conference Paper
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Globally, climate negotiations have highlighted the role of land use sectors in mitigating the climate change. In the last few decades there have been massive deforestation and land use/cover change in the tropics that have contributed substantially to the rising concentration of CO2 atmospheric levels of CO2 to ameliorate the global climatic chang...
Article
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A study on the feeding rate, prey species of the near threatened Oriental Darter Anhinga melanogaster was studied at the Kuttanad wetlands. It showed more or less steady feeding rate throughout the day with a slight reduction in the noon time. The feeding rate was found almost stable from June to September and a declining trend was noticed from Oct...
Article
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The distribution and diversity of phytoplankton in relation with the water quality of Alappuzha Changanasserry canal in the Kuttanad wetland ecosystem, part of Vembanad Kol Ramsar site in Kerala was assessed in the present study. The results showed that from the whole stretch of the canal. Out of these, 39 species belonged to Chrysophyceae, Myxophy...
Article
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The distribution pattern of the arenicolous and limicolous Pontodrilus litoralis (Grube, 1855), a circummundane species, is very fascinating. Through this communication, we are reporting the second record of P. litoralis from the Kerala state, southern India after a time period of 85 years. 38 individuals of this species were collected from coastal...
Article
Full-text available
The distribution pattern of the arenicolous and limicolous Pontodrilus litoralis (Grube, 1855), a circummundane species, is very fascinating. Through this communication, we are reporting the second record of P. litoralis from the Kerala state, southern India after a time period of 85 years. 38 individuals of this species were collected from coastal...
Article
Full-text available
The objective of the study was to evaluate the survival response of multi-drug resistant enteropathogenic Escherichia coli and Salmonella paratyphi to the salinity fluctuations induced by a saltwater barrier constructed in Vembanadu lake, which separates the lake into a freshwater dominated southern and brackish water dominated northern part. There...
Article
Full-text available
The objective of the study was to evaluate the survival response of multi-drug resistant enteropathogenic Escherichia coli and Salmonella paratyphi to the salinity fluctuations induced by a saltwater barrier constructed in Vembanadu lake, which separates the lake into a freshwater dominated southern and brackish water dominated northern part. There...
Article
Carbon assimilation defined as the overall rate of fixation of carbon through the process of photosynthesis is central to the climate change research. The present study compares the two well-known algorithms in satellite based carbon assimilation estimation, the Vegetation Photosynthesis Model (VPM) and the MOD 17A2 GPP Model, over the tropical for...
Article
The climatic variability and the influence of temperature and sea level fluctuations on the earth’s surface configuration during the Holocene are being discussed all over the world. The present study evaluates the palaeo-environmental conditions of western coast of India during this epoch through the analysis of pollen grains embedded in a carbonac...
Article
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The uncontrolled exercise of pesticides in agriculture segment causes a severe environmental degradation problem also, being closely associated with public and workers health hazard. Even though the utilization of pesticides helps to manage diseases thus reduce crop losses and result in improved yield of the crops. The present study aimed at deter-...
Article
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The present study characterises the tree communities with respect to topographic and climatic variables and identifies the most important environmental correlate of species richness in the southern region of Western Ghats Biodiversity Hotspot, India. Digitally derived environmental variables in combination with tree species richness information wer...
Article
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Kumarakom heronry is the biggest of all heronries found in Kerala. We surveyed the breeding population of Oriental darter at this heronry for four years. Total 442 nests were counted at this heronry. 73.5 % of nests were recorded during 2007. After this Kumarakom heronry showed a drastic decline in the number of nests.
Article
Composite membranes were developed from polyamide microfiltration membranes by a combination of two cationic (poly (ethyleneimine)-PEI, chitosan-CHI) and an anionic (poly (acrylic acid)-PAA) polyelectrolyte through layer-by-layer (LbL) assembly. The removal efficiency of these membranes was investigated using two model textile effluents, methylene...
Article
The Industrial Revolution brought about an increased production and discharge of both xenobiotics and natural chemical substances which usually end up in the sediments of water bodies. The tolerance of bacteria to heavy metals has been proposed as an indicator of the potential toxicity of heavy metals to other forms of biota. The present study was...
Article
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Since the launch of the first satellite in 1972, ecologists have been equipped with new tools to address the degradation of tropical forests, previously limited by field-based methods. This article is a review of the state of remote sensing technology in characterizing the degradation of tropical forest. The factors responsible for the structural a...
Article
Mercury, a global pollutant, has become a real threat to the developing countries like India and China, where high usage of mercury is reported. Mercury and other heavy metals deposited in to the aquatic system can cause health risk to the biota. The common edible fishes such as Mugil cephalus, Arius arius, Lutjanus ehrenbergii, Etroplus suratensis...
Article
To assess the prevalence of faecal coliform bacteria and multiple drug resistance among Escherichia coli and Salmonella serotypes from Vembanadu Lake. Systematic microbiological testing. Monthly collection of water samples were made from ten stations on the southern and northern parts of a salt water regulator constructed in Vembanadu Lake in order...
Article
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The avifauna of Kuttanad was studied from January 1995 to June 2007. Two-hundred-and-twenty-five taxa of birds belonging to 15 orders and 59 families were recorded. Among the birds recorded, 38% were migrants. Fifty-five species were found to breed in the area. Family Scolopaceidae showed maximum species diversity. European Roller Coracias garrulus...
Article
The southwestern coast of India was under the influence of local marine environments to a minor extent in the geological past. The sea level along this part of the coast stood around 60-100 m below the present MSL during the last glacial maxima (around 20,000 YBP) and the rivers flowing at that time incised their valley to this base level. Later a...
Article
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Palaeo-environmental interpretation using the fossil remains has attained a world wide attention and the palaeontological studies coupled with geochronology and stratigraphy could bring many dimensions to certain obstinate facets of biogeography and promote not only the theory of evolution, but the concept of plate tectonics also. Throughout geolog...
Article
Kerala State of Indian sub-continent unfortunately possesses a highly imperfect geological record compared to other states. The occurrence of Tertiary and Recent deposits as longitudinal outcrops paralleling the Western coast has led to the view that Kerala was under the influence of local marine environments to a minor extent in the geological pas...
Article
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Carbon stock distribution in different tropical forest types in India is rarely studied although India is a country with mega-diversity. The present study estimates the biomass and carbon stock of major tropical forest types in India, and attempts to identify suitable interpolation techniques for mapping carbon stock. Empirically derived allometric...
Conference Paper
We documented the butterfly fauna and the host plants available in the Mahatma Gandhi University Campus. Total 109 species of butterflies belonging to 85 genera were recorded. This forms 32% of the butterflies documented from the Western Ghats. Eighty four species of plants were found to be used as larval food plants in the campus. Among the butter...
Article
Prevalence of faecal coliform bacteria and the survival of Escherichia coli, Vibrio parahaemolyticus and Salmonella paratyphi were studied in the water and sediment from Vembanadu Lake in the presence and absence of protozoan predators. The density of faecal coliform bacteria ranged between mean MPN value 5080–9000/100ml in water and 110,000–988,00...
Article
The edible fishes Etroplus suratensis and Arius arius were collected from two different sites of Vembanad backwaters. Accumulation of heavy metals such as zinc, cadmium, lead and copper in different tissues of these fishes were analysed. Kidneys showed maximum accumulation of all the metals in both the fishes. Lead and copper were high in Kumarakom...
Article
Wastewater treatment using self-assembled membranes is an upcoming research area and it is believed that this technology is much superior to other conventional membranes. The present study demonstrates the usefulness of chitosan/polystyrene sulfonate (CHI/PSS) based multilayer membranes in the treatment of paper mill and textile effluents. Membrane...
Article
Carbonaceous clay found in the palaeo-deposits of Meenachil River basin was analysed for the total organic carbon, nitrogen and textural characters. Radiocarbon dating of this clay formation and the embedded carbonized wood fragments was also done. The values obtained for the organic carbon, nitrogen and C/N ratio of the carbonaceous clay exhibited...
Article
The variability in ground water potential at different regions of the Meenachil River basin and the remarkable presence and distribution of palaeodeposit of sand at its middle to lower reaches have led to interpret the quantitative geomorphology of the River basin for elucidating the relationship between mathematical expressions and filed observati...
Article
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Tropical forests, which play critical roles in global biogeochemical cycles, radiation budgets and biodiversity, have undergone rapid changes in land cover in the last few decades. This study examines the complex process of land cover change in the biodiversity hotspot of Western Ghats, India, specifically investigating the effects of conservation...
Article
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Exotic weed invasion has been identified as one of the serious environmental problem impacting the structure, composition and function of biological diversity. They are aggressive colonizers, which have flexible habitat requirement and ability to outcompete native species. The present paper describes the distribution and autecology of an exotic wee...
Conference Paper
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The ecotoxic potential of Linear Alkyl-benzene Sulphonate (LAS) detergents on diverse aquatic organisms suggested the need to study their toxicity. The enormous volume discharged into the environment without ample treatment has eventually made LAS persistant in the depleted environment causing hazardous effects (Kruger et al., 1998a). Several studi...
Article
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2667 May 2007 | ISSN 0973-2535 (Print edition); 0973-2551 (Online edition) www.zoosprint.org ABSTRACT The food habits and relative abundance of large carnivores was studied through scat analysis technique in Parambikulam Wildlife Sanctuary from November 2002 to April 2003. A total of 377 scats (103 of Tiger, 188 of Leopard and 86 of Dhole) were ana...