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Ramachandran, K. K.
- Feeding Ecology of Nilgiri Langur (Trachypithecus johnii) in Silent Valley National Park, Kerala, India
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Indian Forester, Vol 127, No 10 (2001), Pagination: 1155-1164Abstract
Feeding ecology of Nilgiri Langur has been studied in the rainforest ecosystem of Silent Valley from 1993 to 1996. Eighty-nine food species were identified through direct observations. A majority of them were typical evergreen species. Monthly and seasonal variations in the percentage frequency of feeding observations on different food items in the diet were observed. The need of conserving the evergreen habitats for the endangered Nilgiri Langur is discussed.
- Recent Population Trends and Management of Lion-tailed Macaque (Macaca silenus) in Silent Valley National Park, Kerala, India
Abstract Views :217 |
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Indian Forester, Vol 124, No 10 (1998), Pagination: 833-840Abstract
Fourteen Lion-tailed Macaque troops were identified in Silent Valley National Park and adjacent areas with a total 275 individuals. Of these, 8% were adult females and 45% were adult females. The population was monitored for yearly variation in the troop size. An increase of troop size was noticed in most of the cases. Management strategies to ensure the long-term survival of the highly endangered Lion-tailed Macaque in Silent Valley forests are discussed.- Environmental Aspects of Geology
Abstract Views :174 |
PDF Views:143
Authors
Affiliations
1 Centre for Earth Scince Studies Trivandrum, IN
1 Centre for Earth Scince Studies Trivandrum, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 26, No 2 (1985), Pagination: 149-158Abstract
No Abstract.Full Text
- Environmental Geology, Indian Context
Abstract Views :224 |
PDF Views:135
Authors
Affiliations
1 Centre for Earth Science Studies, Trivandram - 695 031, IN
1 Centre for Earth Science Studies, Trivandram - 695 031, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 32, No 3 (1988), Pagination: 253-254Abstract
No Abstract.Full Text
- Geochemical Characteristics of Mudbank Environment - A Case Study from Quilandy, West Coast of India
Abstract Views :181 |
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Authors
Affiliations
1 Marine Science Division, Centre for Earth Science Studies, Akkularn, Trivandrurn 695031, IN
1 Marine Science Division, Centre for Earth Science Studies, Akkularn, Trivandrurn 695031, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 33, No 1 (1989), Pagination: 55-63Abstract
Aerial variatron of SiO2, Al2O3, MgO, CaO, TiO2, K2O and Na2O in the Mudbank sediments off Quilandy are discussed. A comparative study of textural classes versus the elemental concentration revealed a size dependence factor on the elemental speciation. Chemical variability depicted from cluster analysis suggests three interrelated elemental groups, such as (I) Al2O3, Fe2O3, Na2O and MgO probably controlled by hydrous aluminosilicates in the finer fractions, (2) TiO2, CaO and SiO2 with coarser materials especially CaO with shell fragments, (3) lone element K2O influenced by both hydrous aluminosilicates and feldspars.
Mudbanks are conspicuous with high load suspension. Initial triggering which brought the sediments into suspension is explained in terms of convulsive physical action during the onset of southwest monsoon. It has been found that mudbank sediments are enriched with alumina and ferric oxide. Salinity reduction in the nearshore waters due to monsoonal precipitation is an ideal condition (optimum electrolitic concentration) to defloculate and disperse the sediments into suspension in the presence of phosphate as a natural peptizer. Hence apart from the physical mechanism of suspension, dispersion as a chemical mechanism for the sustenance of suspension is suggested.
- Sediment Characteristics, Processes and Stability of the Beaches in the Northern Kerala Coast, India
Abstract Views :199 |
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Authors
Affiliations
1 Marine Science Division, Centre for Earth Science Studies, P. O. Box No. 7250, Akkulam, Trivandrum, 695 031, IN
1 Marine Science Division, Centre for Earth Science Studies, P. O. Box No. 7250, Akkulam, Trivandrum, 695 031, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 38, No 1 (1991), Pagination: 82-95Abstract
The cyclicity in the erosional and accretional pattern is monsoon controlled. The erosion during monsoon (May-August) and accretion during pre-monsoon (January-April) and post-monsoon (September-December) are well defined. The transport trends derived from the progressive changes in the grain-size characteristics show relatively better correlation with the measured trends where they are not influenced by the input of sediments from multiple sources. The obliquely approaching swell waves which generate intense northerly longshore currents during non-monsoon season favour accretion of the beaches. The foreshore in the accreted zones are gentler and are characterized by finer and negatively skewed sediments. This zone exhibits a higher period for the breaking waves. The converse is true in the beaches where erosion is prevalent during the monsoon season.Keywords
Sedimentology, Grain-Size, Sediment Transport, Beach Stability, Kerala Coast.- Quartz Grain Surface Textures as Indicators of Depositional History of Beach and Strand Plain Sediments Along the North Kerala Coast
Abstract Views :180 |
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Authors
Affiliations
1 Marine Science Division, Centre For Earth Science Studies, Trivandrum 695 031, IN
2 Nagarjuna University, Nagarjuna Nagar 522510, A.P., IN
1 Marine Science Division, Centre For Earth Science Studies, Trivandrum 695 031, IN
2 Nagarjuna University, Nagarjuna Nagar 522510, A.P., IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 40, No 6 (1992), Pagination: 501-508Abstract
SEM analysis of quartz grain surfaces from the strand plain show many of the characteristic textures that are produced under sub-aqueous environments with second generation features of wind action. It is inferred that the initial stage of deposition of the strand plain sediments was associated with a wave dominated environment. With emergence of this coast, the strand plain sediments were exposed to sub-aerial action, thus registering both sub-aqueous and sub-aerial action features.Keywords
Sedimentology, Coastal Geomotphology, Kerala Coast.- The State of Myristica Swamp Forests in Southern Western Ghats, India - Butterfly Species Richness as an Indicator
Abstract Views :176 |
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Authors
Affiliations
1 Department of Zoology, St. Thomas' College, Thrissur-1, Kerala, IN
2 Kerala Forest Research Institute, Peechi, Thrissur, Kerala, IN
1 Department of Zoology, St. Thomas' College, Thrissur-1, Kerala, IN
2 Kerala Forest Research Institute, Peechi, Thrissur, Kerala, IN
Source
Indian Forester, Vol 141, No 10 (2015), Pagination: 1056-1066Abstract
Species richness of butterflies in and around the highly fragmented, threatened and restricted patches of Myristica swamp forests in South Western Ghats, Kerala, India was documented. Eighty species of butterflies belonging to 5 families were recorded from these swamp forests with a land area of less than 1.5 km2 (149.75 ha). Species composition inside and outside the swamps showed above 80% similarity Presence-absence of butterfly species was affected by variations in host plant diversity, % of canopy cover, % of inundated area and % of ground litter cover. Habitat usage studies indicated that while habitat specialists were restricted to larger patches of evergreen forests, habitat generalists were not similarly constrained and formed the bulk of the species. The ecotone area between the swamps and the adjacent matrix had relatively more number of species, except where the ecotone had been disturbed. The increase in the butterfly species diversity at the expense of habitat specialists and the proliferation of generalists is an indicator of cryptic changes in the swamp environment leading to increase in microhabitats and host plants associated with disturbance and call for immediate conservation measures.Keywords
Butterfly, Myristica Swamp Forests, Species Richness, Habitat, Conservation.- Species Abundance Distributions of Selected Communities in the Myristica Swamp forests of Southern Kerala
Abstract Views :212 |
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Authors
Affiliations
1 Department of Zoology, St Thomas’ College, Thrissur 680 001, IN
2 Department of Tree Physiology, Kerala Forest Research Institute, Peechi, Thrissur 680 653, IN
3 Department of Wildlife, Kerala Forest Research Institute, Peechi, Thrissur 680 653, IN
4 Department of GIS & Remote Sensing, Kerala Forest Research Institute, Peechi, Thrissur 680 653, IN
1 Department of Zoology, St Thomas’ College, Thrissur 680 001, IN
2 Department of Tree Physiology, Kerala Forest Research Institute, Peechi, Thrissur 680 653, IN
3 Department of Wildlife, Kerala Forest Research Institute, Peechi, Thrissur 680 653, IN
4 Department of GIS & Remote Sensing, Kerala Forest Research Institute, Peechi, Thrissur 680 653, IN
Source
Current Science, Vol 107, No 3 (2014), Pagination: 447-453Abstract
The species abundance distribution (SAD) utilizes all the information gathered in a community and is the most complete mathematical description of the data. Myristica swamp forests are an endemic, highly fragmented ecosystem, naturally restricted due to systematic destruction and the special abiotic conditions required for their survival. Species diversity of amphibians, reptiles and trees in the Myristica swamp forests of southern Western Ghats in Kerala was documented using standard protocols for two years. Conventional species abundance distribution models could not be fitted into the datasets of this study. Graphical representations of the distribution of the dataset suggest that existence of multiple peaks on a log scale does not reject the universal hollow curve law on the arithmetic scale, but it will reject all SAD models producing unimodal curves. Various studies using SAD as a tool for community and ecosystem studies were reviewed and it was found that the presence of many species of intermediate abundance and decrease in rare species in our datasets could be an indication of natural distributions moving apart under disturbance and enrichment. Deconstruction and identification of resident and transient groups was done. We suggest that the Myristica swamps, which are situated in an area with high potential for rare species, may be in a transition due to disturbance and fragmentation. Ground truthing and previous studies already indicate these swamp forests as highly fragmented and disturbed.Keywords
Amphibians, Conservation, Myristica Swamps, Reptiles, Species Abundance Distribution, Trees.Full Text
- Evaluation of Line Transect Sampling Technique in Estimating Elephant Abundance in Forests Using Dung Survey
Abstract Views :600 |
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Authors
Affiliations
1 Southern Regional Station, National Dairy Research Institute, Bangalore, IN
2 Kerala Forest Research Institute, Peechi, Thrissur District 680 653 Kerala, IN
1 Southern Regional Station, National Dairy Research Institute, Bangalore, IN
2 Kerala Forest Research Institute, Peechi, Thrissur District 680 653 Kerala, IN
Source
Indian Forester, Vol 142, No 10 (2016), Pagination: 959-964Abstract
Line transect sampling technique is widely applied for estimating the biological population in forests. Recently, this technique has been in use for the estimation of elephant abundance using dung survey. The method of transforming dung count into elephant density requires dung density, which is corrected by defecation and decay rate. In this paper, the performance of the line transect sampling technique (LTS) in dung surveys with particular reference to variation in the number of detections of dung piles caused by annual rainfall variability was evaluated. The data set for this purpose was from the estimation of elephant population in the State of Kerala during the years 2005, 2007 and 2010, covering about 9000 km2. The study showed that the presence of dung piles and its detection probability were dependent on the level of rainfall in the two months preceding the date of dung survey. However, the LTS could provide comparable dung density estimates under the highly varying number of dung piles present in the area due to differences in the annual rainfall pattern.Keywords
Distance Sampling, Detection Probability, Elephant Density, Rainfall Variability.References
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- Sivaram M., Ramachandran K.K., Nair P.V. and Jayson E.A., Population estimation of Wild Elephants in the Elephant Reserves of Kerala State2005, Kerala Forest Research Institute, Peechi, KFRI Extension Report, 2005, No.18, p.46.
- Sivaram M., Ramachandran K.K., Nair P.V. and Jayson E.A. (2007). Population estimation of Wild Elephants in the Elephant Reserves of Kerala State-2007, Kerala Forest Research Institute, Peechi, KFRI Extension Report, No.27, p.40.
- Sivaram M., Ramachandran K.K., Jayson E.A. and Nair P.V. (2010). Wild Elephant Census of Kerala State-2010, Kerala Forest Research Institute, Peechi, KFRI Extension Report, 2011, No.52, p.40.
- Thomas L., Laake J.L., Strinberg S., Marques F.F.C., Buckland S.T., Borchers D.L., Anderson D.R., Burnham K.P., Hedley S.L., Pollard J.H., Bishop J.R. and Marques T. A. (2006). Distance 5.0, Release 2, Research Unit for Wildlife population Assessment, University of St. Andrews, U.K.
- Turnock B.J. and Quinn II T.J. (1991). The effect of responsive movement on abundance estimation using line transect sampling. Biometrics, 47: 701-715.
- Varman K.S., Ramakrishnan U. and Sukumar R. (1995). Direct and indirect methods of counting elephants: A comparison of results from Mudumalai Sanctuary. In: A week with Elephants: Proceedings of the International Seminar on Asian Elephants (J.C. Daniel, J. C. and S.H. Datye eds),Oxford University Press, New Delhi.
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- South Asian Subtropical Low-Level Jet:Influence on Regional Hydrology and Aerosol Optical Depth
Abstract Views :238 |
PDF Views:87
Authors
Affiliations
1 National Centre for Earth Science Studies, Akkulam, Thiruvananthapuram 695 011, IN
2 University of Hyderabad, Central University P.O., Prof. C.R. Rao Road, Gachibowli, Hyderabad 500 046, IN
1 National Centre for Earth Science Studies, Akkulam, Thiruvananthapuram 695 011, IN
2 University of Hyderabad, Central University P.O., Prof. C.R. Rao Road, Gachibowli, Hyderabad 500 046, IN
Source
Current Science, Vol 117, No 5 (2019), Pagination: 852-858Abstract
A 38-year high-resolution wind climatology shows a consistent occurrence of hitherto unreported South Asian subtropical low-level jets (SASLLJs) over the 31°–35°N and 60°–62°E latitude–longitude region, occurring throughout the year are the northerly LLJs (NLLJs) and southerly LLJs (SLLJs). The NLLJ is persistent mostly during the monsoon season. The NLLJ is frequent, unlike the SLLJ. The synoptic heat low in South Asia (62°–66°E and 27°–32°N) and the anticyclone over Turkmenistan (40°–50°N and 50°– 60°E) are critical in inducing the NLLJ. Regional topography permits direct mid-latitude air intrusion into the subtropical region. Importantly, we find that the NLLJ results in enhancing the transportation of dust to the Indian subcontinent and the northern part of the Arabian Sea due to wind blows. Long-term NLLJ intensity displays waning trend because of the weakening of pressure gradients between the heat low in South Asia and over Turkmenistan.Keywords
Aerosol Optical Depth, Low-Level Jet, Regional Hydrology, Rainfall.Full Text
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