Refine your search
Co-Authors
Journals
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
Ramachandran, K. K.
- Feeding Ecology of Nilgiri Langur (Trachypithecus johnii) in Silent Valley National Park, Kerala, India
Abstract Views :312 |
PDF Views:0
Authors
Source
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 :261 |
PDF Views:0
Authors
Source
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.- The State of Myristica Swamp Forests in Southern Western Ghats, India - Butterfly Species Richness as an Indicator
Abstract Views :234 |
PDF Views:0
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 :404 |
PDF Views:130
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 :728 |
PDF Views:0
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
- Anderson D.R. and Southwell C. (1995). Estimates of macropod density from line transect surveys relative to analyst expertise. J. Wild Manage, 59(4): 852-857.
- Barnes R.F.W., Asamoah-Boateng B., Majam J.N. and Agyei-Ohemeng J. (1997). Rainfall and the population dynamics of elephant dung-piles in the forests of southern Ghana. Afr. J. Eco., 35: 39-52.
- Barnes R.F.W. and Dunn A. (2002). Estimating forest elephant density in Sapo National Park (Liberia) with a rainfall model. Afr. J. Eco., 40: 159163.
- Borchers D., Margues T., Gunnlaugsson and Jupp P. (2010). Estimating distance sampling detection functions when distances are measured with errors. J. Agricultural, Biological and Environmental Statistics, 15: 346-361.
- Buckland S.T., Anderson D.R., Burnham K.P., Laake J.L., Borchers D.L. and Thomas L. (2001). Introduction to distance sampling: Estimating abundance of biological populations,Oxford University Press Inc, New York.
- Buckland S.T., Anderson D.R., Burnham K.P., Laake J.L., Borchers D.L. and Thomas L. (2004). Advanced Distance Sampling, Oxford University Press Inc, New York.
- Buckland S.T., Plumptre A.J., Thomas L. and Rexstad E.A. (2010a). Line Transect Sampling of primates: Can animal-to-observer distance methods work? Int. J. Primatol., 31: 485-499.
- Buckland S.T., Plumptre A.J., Thomas L. and Rexstad E.A. (2010b). Design and analysis of line transect surveys for Primates. Int. J. Primatol., 31: 833-847.
- Burnham K.P., Anderson D.R. and Laake J.L. (1980). Estimation of density from line transects sampling of biological populations. Wildlife Monographs, 72: 202.
- Forcard S., Isotti R. and Tinell A. (2002). Line transect estimates of ungulate populations in a Mediterranean Forest. J. Wild Manage, 66(1): 48-58.
- Guthery F.S. (1988). Line transect sampling of probable density of Rangeland: Evaluation and recommendations. Wildlife Society Bulletin, 16: 193-203.
- The Hindu (2012) The Hindu archives. http://www.thehindu.com/navigation/?type=static&page=archive, accessed on 30 April 2012.
- Mercey K.A. and Jayaraman K. (1999). Predicting the variation in detection function in line transect sampling through random parameter model. Environmental and Ecological Statistics, 6(4): 341-350.
- Mercey K.A. and Jayaraman K. (2002) Effect of errors in visual assessment of distance in line transect sampling. In: Proceedings of the 14th Kerala Science Congress 29-31 January 2002 (M.R.Das eds), Science and Technology Department, Government of Kerala, Thriuvananthapuram, 2002, pp. 455-458.
- Mercey K.A., and Jayaraman K. (2004). Detection function models for indirect evidence of elephant and gaur. Indian Forester, 130(10): 12011203.
- 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.
- White G.C., Bartmann R.M., Carpenter L.M. and Garrot R.A. (1989). Evaluation of aerial line transects for estimating deer densities. J. Wild Manage, 53(3): 625-635.
- South Asian Subtropical Low-Level Jet:Influence on Regional Hydrology and Aerosol Optical Depth
Abstract Views :462 |
PDF Views:119
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
References
- Joseph, P. V. and and Sijikumar, S., Intraseasonal variability of the low-level jet stream of the Asian summer monsoon. J. Climate, 2004, 17, 1449–1458.
- Zou, H. et al., Local wind system in the Rongbuk Valley on the northern slope of Mt. Everest. Geophys. Res. Lett., 2008, 35, L13813.
- Yu, Y., Notaro, M., Kalashnikova, O. V. and Garay, M. J., Climatology of summer Shamal wind in the Middle East. J. Geophys. Res. Atmos., 2016, 121, 289–230.
- Stensrud, D. J., Importance of low-level jets to climate: a review. J. Climate, 1996, 9, 1698–1711.
- Membery, D. A., Low level wind profiles during the Gulf Shamal. Weather, 1983, 38, 18–24.
- Gadgil, S., The Indian monsoon and its variability. Annu. Rev. Earth Planet. Sci., 2003, 31(1), 429–467.
- Gadgil, S. and Gadgil, S., The Indian monsoon, GDP and agriculture. Econ. Polit. Wkly., 2006, 41(47), 4887–4895.
- Findlater, J., A major low-level air current near the Indian Ocean during the northern summer. Q. J. R. Meteorol. Soc., 1969, 95, 362–380.
- Liu, M., Westphal, D. L., Holt, T. R. and Xu, Q., Numerical simulation of a low-level jet over complex Terrain in Southern Iran. Mon. Weather Rev., 2000, 128, 1309–1327.
- Alizadeh-Choobari, Zawar-Reza, P. and Sturman, A., The ‘wind of 120 days’ and dust storm activity over the Sistan Basin. Atmos. Res., 2014, 143, 328–341.
- Ramaswamy, V., Muraleedharan, Babu, P. M. and Prakash, C., Mid-troposphere transport of middle-east dust over the Arabian sea and its effect on rainwater composition and sensitive ecosystems over India. Sci. Rep., 2017, 7, 1–8.
- Gadgil, S., The Indian monsoon – how do we get rain? Resonance, 2006, 11, 8–21.
- Lau, W. K. M., Waliser, D. E. and Goswami, B. N., South Asian monsoon. In Intraseasonal Variability in the Atmosphere–Ocean Climate System, Springer Praxis Books, Springer, Berlin, Germany, 2012, pp. 21–72.
- Neiman, P. J., Ralph, F. M., White, A. B., Kingsmill, D. E. and Persson, P. O., The statistical relationship between upslope flow and rainfall in California’s coastal mountains: observations during CALJET. Mon. Weather Rev., 2002, 130, 1468–1492.
- Panziera, L. and Germann, U., The relation between air flow and orographic precipitation on the southern side of the Alps as revealed by weather radar. Q. J. R. Meteorol. Soc., 2010, 136, 222–238.
- Vinoj, V., Rasch, P. J., Wang, H., Yoon, Jin-Ho, Landu, K., Singh, B. and Ma, Po-Lun, Short-term modulation of Indian summer monsoon rainfall by West Asian dust. Nature Geosci., 2014, 7, 308–313.
- Platnick, S. et al., MODIS Atmosphere L3 Daily Product. NASA MODIS Adaptive Processing System, Goddard Space Flight Center, USA, 2015; http://dx.doi.org/10.5067/MODIS/MOD08_D3.006.
- Huffman, G. J. et al., The TRMM Multisatellite Precipitation Analysis (TMPA): quasi-global, multiyear, combined-sensor precipitation estimates at fine scales. J. Hydrometeorol., 2007, 8, 38– 55.
- Dee, D. P. et al., The ERA-interim reanalysis: configuration and performance of the data assimilation system. Q. J. R. Meteorol. Soc., 2011, 137, 553–597.
- Saha, S. et al., The NCEP climate forecast system reanalysis. Bull. Am. Meteorol. Soc., 2010, 91, 1015–1057.
- Rao, Y. P., Meteorological Monograph Synoptic Meteorology, No. 1/1976: South West Monsoon, India Meteorological Department, 1979, pp. 1–379; http://imdpune.gov.in/Weather/Reports/sw%20monsoon%20whole%20book.pdf
- Pant, G. and Kumar, K., Climates of South Asia, John Wiley, Hoboken, NJ, USA, 1997.
- Tyrlis, E., Lelieveld, J. and Steil, B., The summer circulation over the eastern Mediterranean and the Middle East: influence of the South Asian monsoon. Climate Dyn., 1997, 40, 1103.
- Najafi, M. S., Sarraf, B. S. and Zarrin, A., Climatology of atmospheric circulation patterns of Arabian dust in western Iran. Environ. Monit. Assess., 2017, 189, 473.
- Bollasina, M. and Nigam, S., The summertime ‘heat’ low over Pakistan/Northwestern India: evolution and origin. Climate Dyn., 2011, 37, 957–970.
- Krishnan, R., Kumar, V., Sugi, M. and Yoshimura, J., Internal feedbacks from monsoon–midlatitude interactions during droughts in the Indian summer monsoon. J. Atmos. Sci., 2009, 66(3), 553–578.
- Anoop, T. R. et al., On the generation and propagation of Makran swells in the Arabian Sea. Int. J. Climatol., 2019, 1–9.