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Ramachandran, K. K.
- Species Abundance Distributions of Selected Communities in the Myristica Swamp forests of Southern Kerala
Abstract Views :213 |
PDF Views:79
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
- South Asian Subtropical Low-Level Jet:Influence on Regional Hydrology and Aerosol Optical Depth
Abstract Views :240 |
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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