Ecological structure of a herpetological assemblage in South India

1987 ◽  
Vol 8 (3) ◽  
pp. 189-202 ◽  
Author(s):  
M. Koshy ◽  
Robert F. Inger ◽  
H.B. Shaffer ◽  
R. Bakde
Keyword(s):  
South India ◽  
Niche Breadth ◽  
Niche Overlap ◽  
Common Species ◽  
Evergreen Forest ◽  
Terrestrial Species ◽  
South Indian ◽  
Tropical Evergreen Forest ◽  
The Western Ghats ◽  
Level Of Analysis

AbstractWe collected detailed microhabitat information on 1460 specimens comprising 52 species of amphibians and reptiles from a small area of tropical evergreen forest in South India. Although most individuals were found in non-riparian situations, the number caught in and along streams was higher than expected on the basis of collecting effort. Very few animals were caught under logs and rocks. When niche breadth values are corrected for variation in sample size, we find no correlation between magnitude of niche breadth and general habitat usage, such as terrestriality vs. arboreality. A cluster analysis of 28 common species using niche overlap values reveals one group of 6 terrestrial species with very high niche overlap values and high co-occurrence within collecting sorties; this group probably represents a genuine terrestrial guild. Another set of 4 terrestrial species is peripherally associated with the first 6, whereas the remaining species show generally low overlap values. Altitudinal restriction is an almost ubiquitous feature of the distribution of species in this fauna, with distinct groups of low (below 300 m), intermediate (300-399 m), and high altitude (above 399 m) taxa roughly corresponding to major shifts in forest types. At a broader level of analysis, we find considerable evidence for local endemism within partially isolated hill ranges in the Western Ghats, suggesting that geographic isolation may be an important contributing factor to the diversity of the South Indian herpetofauna.

Structure and floristic composition of a tropical evergreen forest in south-west India

1996 ◽  
Vol 12 (2) ◽  
pp. 191-214 ◽  
Author(s):  
Jean-Pierre Pascal ◽  
Raphael Pelissier
Keyword(s):  
Western Ghats ◽  
Basal Area ◽  
Floristic Composition ◽  
Evergreen Forest ◽  
Systematic Sampling ◽  
Importance Value Index ◽  
Importance Value ◽  
Tropical Evergreen Forest ◽  
Western Ghats Of India ◽  
The Western Ghats

ABSTRACTA permanent plot of 28 ha was established in a dense wet evergreen forest in the Western Ghats of India to study the functioning of the ecosystem. Since April 1990, 1981 trees of ≥30 cm gbh have been enumerated in a systematic sampling of five strips totalling 3.12 ha. This paper describes the main structural and floristic characteristics of the plot.The density (635 trees ≥30 cm gbh per hectare) and basal area (39.7 m2 ha−1) are high. Despite the high diversity (Simpson's D = 0.92 and Shannon's H' = 4.56), four species are distinctly, dominant in terms of an importance value index (relative density + relative basal area). Each of these four species occupies a different layer in the ecosystem: Humboldtia brunonis Wall. (Fabaceae) dominates the undergrowth, Myristica dactyloïdes Gaertn. (Myristicaceae) the intermediate strata, Valeria indica L. (Dipterocarpaceae) the higher canopy level and Dipterocarpus indicus Bedd. (Dipterocarpaceae) the emergents. This pronounced species hierarchy is one of the most important characteristics of the evergreen forests of the Western Ghats. The two dipterocarps account for 20.1% of the total number of trees and contribute 40.9% to the total basal area. This formation can, therefore, be considered as the westernmost lowland dipterocarp forest of Asia.Analysis of the spatial variations in the floristic composition and in the structure of the main species populations shows that two kinds of mature phases can be identified: where the topography is raised and gently sloping, the vertical structure of the stand is discontinuous, with Dipterocarpus indicus and Vateria indica forming an emergent layer above a dense undergrowth; on slopes, the stand is lower, vertically continuous and saturated with Valeria indica and Myristica dactyloïdes. The link between the structure of the stand and dynamic processes is discussed.

Rediscovery, extended enumeration and conservation assessment of Henckelia lyrata (Gesneriaceae) in Western Ghats, India

Phytotaxa ◽  
2016 ◽  
Vol 284 (2) ◽  
pp. 147
Author(s):  
M.P. GEETHAKUMARY ◽  
S. DEEPU ◽  
A.G. PANDURANGAN ◽  
E.S. SANTHOSH KUMAR
Keyword(s):  
Sri Lanka ◽  
Western Ghats ◽  
South India ◽  
Morphological Characters ◽  
The Philippines ◽  
Indian Species ◽  
Conservation Assessment ◽  
South Indian ◽  
Southern Thailand ◽  
The Western Ghats

The generic name Henckelia Sprengel (1817: 402) was proposed in honor of Leo F. V. Henckel von Donnersmark (1785–1861), a German administrator and passionate botanist. However, even though the genus had priority over Didymocarpus Wallich (1819: 378), in view of its wider usage the latter name was conserved (Vitek et al. 2000). Henckelia Sprengel (1817: 402) was resurrected from synonymy of Didymocarpus by Weber & Burtt (1997), separating them by an array of morphological characters, to give a more natural taxonomic unit. The genus Henckelia has about 180 species distributed from south India and Sri Lanka over Sumatra, southern Thailand, Malaya Peninsula, Borneo to the Philippines, Sulawesi and New Guinea. It accommodates most of the south Indian species formerly placed in Didymocarpus (Middleton et al. 2013). At present, 30 species are known to occur in India, of which 13 are endemic to the Western Ghats (Janeesha & Nampy 2015).

scholarly journals Niche Breadth and Overlap of Sphagnum Species in Costa Rica

1995 ◽  
Vol 11 (1) ◽  
pp. 119-127
Author(s):  
Cyrus B. McQueen
Keyword(s):  
Costa Rica ◽  
North America ◽  
South America ◽  
Niche Breadth ◽  
Niche Overlap ◽  
Common Species ◽  
The Common ◽  
Sphagnum Magellanicum

Niche breadth and overlap values of Sphagnum species in Costa Rica are similar to those reported for Sphagnum-dominated peatlands in North America. Sphagnum magellanicum Brid. and S. sparsum Hampe have the broadest niche breadth of the common species in Costa Rica. Although S. sancto-josephense Crum & Crosby has a relatively narrow niche breadth, it is one of the most common species along with S. magellancium and S. sparsum in the Sphagnum habitats of Costa Rica. Niche overlap is high among species with the exception of S. platyphyllum (Braithw.) Warnst. which is found in habitats that are rich in iron. The pH, conductivity, and concentrations of Ca, Fe, Mg, Mn, Na, K, and P of Sphagnum habitats in Costa Rica are similar to those reported for páramo habitats in South America.

Impact of selective logging on the dynamics of a low elevation dense moist evergreen forest in the Western Ghats (South India)

1998 ◽  
Vol 105 (1-3) ◽  
pp. 107-119 ◽  
Author(s):  
Raphaël Pélissier ◽  
Jean-Pierre Pascal ◽  
François Houllier ◽  
Henri Laborde
Keyword(s):  
Western Ghats ◽  
South India ◽  
Selective Logging ◽  
Evergreen Forest ◽  
The Western Ghats

Diet and habitat-niche relationships within an assemblage of large herbivores in a seasonal tropical forest

2012 ◽  
Vol 28 (4) ◽  
pp. 385-394 ◽  
Author(s):  
Farshid S. Ahrestani ◽  
Ignas M. A. Heitkönig ◽  
Herbert H. T. Prins
Keyword(s):  
Seasonal Variation ◽  
Habitat Selection ◽  
South India ◽  
Niche Breadth ◽  
Niche Overlap ◽  
Dry Season ◽  
Wet Season ◽  
Large Herbivores ◽  
Axis Axis ◽  
Habitat Niche

Abstract:There is little understanding of how large mammalian herbivores in Asia partition habitat and forage resources, and vary their diet and habitat selection seasonally in order to coexist. We studied an assemblage of four large herbivores, chital (Axis axis), sambar (Cervus unicolor), gaur (Bos gaurus) and Asian elephant (Elephas maximus), in the seasonal tropical forests of Bandipur and Mudumalai, South India, and tested predictions regarding the species’ seasonal diet browse : graze ratios, habitat selection and habitat-niche preference and overlap. Field data collected for the study included the seasonal variation in grass quality, the seasonal variation in δ13C in the species’ faeces and the seasonal variation in the species’ habitat selection and overlap using a grid-based survey. Results of the δ13C analyses showed that the chital was more of a grazer in the wet season (−17.9‰ to −21.6‰), but that it increased the proportion of browse in its diet in the dry season (−25.6‰ to −27.7‰); the gaur was a grazer for most of the year (−15.3‰ to −18.6‰); the sambar preferred to browse throughout the year (−21.1‰ to −30.4‰); and that the elephant was a mixed feeder (−14.2‰ to −21.4‰). Elephant habitat-niche breadth was high (0.53 in wet and 0.54 in dry) and overlapped equally with that of the other species in both seasons (0.39–0.94). The gaur had the most restricted habitat-niche breadth in both seasons (0.25 in wet and 0.28 in dry), and it switched from the moist deciduous habitat in the dry season to the dry deciduous habitat in the wet season. These results offer the first insights into the seasonal variation in browse : graze diet ratios and the habitat-niche overlap amongst the common largest-bodied mammalian herbivore species found in South India.

Unusual temporal niche overlap in a phytophagous bat ensemble of western Cuba

2013 ◽  
Vol 29 (6) ◽  
pp. 511-521 ◽  
Author(s):  
Carlos A. Mancina ◽  
Ivan Castro-Arellano
Keyword(s):  
Activity Patterns ◽  
Biosphere Reserve ◽  
Niche Overlap ◽  
Evergreen Forest ◽  
Temporal Niche ◽  
Artibeus Jamaicensis ◽  
Forest Sites ◽  
Tropical Evergreen Forest ◽  
Reproductive Females ◽  
Temporal Overlap

Abstract:We assessed the differences and similarities in diel activities among five phytophagous bat species at two habitats over two seasons within the Sierra del Rosario Biosphere Reserve in Cuba. We characterized temporal patterns of activity and overlap of temporal activity for frugivore and nectarivore bat species (Artibeus jamaicensis, Monophyllus redmani, Phyllonycteris poeyi, Phyllops falcatus and Brachyphylla nana) that occur in tropical evergreen forest sites with distinct altitude and vegetation structure during wet and dry seasons. Capture frequencies using mist-nets of 1180 capture events were the empirical basis for analyses. For each species we compared activity patterns between habitats, between seasons, between males and females, as well as between reproductive and non-reproductive females. We also assessed temporal overlap among each possible pair of species at each habitat and used Monte Carlo simulations to evaluate assemblage-wide temporal niche overlap using a new algorithm, termed Rosario, designed specifically for temporal data. The two habitats had the same species composition and bat diel rhythms tended to be consistent across habitats, seasons and sexes for most bat species. In general bat species pairwise temporal niche overlap was high, and the ensemble-wide temporal overlap was consistently high across habitats and seasons indicating a common constraint for bat activities. Activity peaks of most bat species coincided at 4–5 h after sunset, this being in sharp contrast to other Neotropical bat assemblages at continental sites where activity peaks usually overlap within the first 2 h after sunset. This strong disparity in timing of activity peaks between continental and insular bat assemblages can provide the framework for the generation of hypotheses that explain the potential role of time as a mediator of ecological interactions in bat assemblages.

scholarly journals Niche Diversification of Sphagnum in Bolivia

1997 ◽  
Vol 13 (1) ◽  
pp. 65-73
Author(s):  
Cyrus B. McQueen
Keyword(s):  
North America ◽  
Niche Breadth ◽  
Niche Overlap ◽  
Common Species ◽  
Cloud Forests ◽  
Bolivian Andes ◽  
Niche Diversification

Niche breadth values of Sphagnum species in the páramo and cloud forests of Bolivia are similar to those reported for Sphagnum-dominated peatlands in North America, but niche overlap values are higher for Sphagnum species in Bolivia. The pH, conductivity, and concentrations of Ca, Mg, Na, K, and P suggest that Sphagnum habitats in Bolivia are ombrotrophic in nature. Sphagnum is limited to small, scattered carpets in the páramo and cloud forests of the Bolivian Andes between 1800 and 4200 m. Common species found in these habitats include S. alegrense Warnst., S. boliviae Warnst., S. cuspidatum Ehrh., S. magellanicum Brid., S. oxyphyllum Warnst., S. recurvum P. Beauv., S. sanctojosephense Crum & Crosby, and S. sparsum Hampe.

scholarly journals An Assessment of Skeletal Craniofacial Asymmetry in South Indian Population

2012 ◽  
Vol 13 (1) ◽  
pp. 80-84 ◽  
Author(s):  
G Anil Kumar ◽  
Saibel Farishta ◽  
G Baiju ◽  
VK Taneja ◽  
RC Minocha ◽  
...  
Keyword(s):  
College Students ◽  
South India ◽  
Indian Population ◽  
Cranial Base ◽  
The Other ◽  
South Indian Population ◽  
X Rays ◽  
Base Area ◽  
South Indian ◽  
The Face

ABSTRACT The present study was undertaken to assess the skeletal craniofacial asymmetry in South Indian population by a posteroanterior cephalometric radiographic method. The skeletal craniofacial structures on one side of the face were compared with that of the other, by drawing various triangles representing different craniofacial regions. The sample consisted of 60 subjects (30 males and 30 females) aged between 18 to 25 years, who were mainly dental college students from South India. Overall 52 X-rays were obtained, with four errors each in the male and the female groups. The results revealed that the total facial structures in the South Indian population were larger on the left side (statistically insignificant). The cranial base area exhibited a greater degree of asymmetry than any other component area of the face, which might be due to the inaccuracy at the condylar point. How to cite this article Taneja VK, Kumar GA, Farishta S, Minocha RC, Baiju G, Gopal D. An Assessment of Skeletal Craniofacial Asymmetry in South Indian Population. J Contemp Dent Pract 2012;13(1):80-84.

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