Short-term changes in tree populations in a tropical evergreen forest at Varagalaiar, Western Ghats, India

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.

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Alpha diversity of lianas in a tropical evergreen forest in the Anamalais, Western Ghats, India

Diversity and Distributions ◽

10.1046/j.1472-4642.2000.00057.x ◽

2000 ◽

Vol 6 (1) ◽

pp. 1-14 ◽

Cited By ~ 29

Author(s):

S. Muthuramkumar ◽

N. Parthasarathy

Keyword(s):

Western Ghats ◽

Alpha Diversity ◽

Evergreen Forest ◽

Tropical Evergreen Forest

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Tree-liana relationships in a tropical evergreen forest at Varagalaiar, Anamalais, Western Ghats, India

Journal of Tropical Ecology ◽

10.1017/s0266467401001274 ◽

2001 ◽

Vol 17 (3) ◽

pp. 395-409 ◽

Cited By ~ 14

Author(s):

S. MUTHURAMKUMAR ◽

N. PARTHASARATHY

Keyword(s):

Western Ghats ◽

Negative Binomial ◽

Permanent Plot ◽

Evergreen Forest ◽

Binomial Model ◽

Breast Height ◽

Tropical Evergreen Forest ◽

Family Level ◽

The Mean ◽

Better Than

In a 30-ha permanent plot of tropical evergreen forest at Varagalaiar, Indian Western Ghats, all trees ≥ 30 cm girth at breast height (gbh) were examined for the presence of lianas ≥ 1 cm dbh. The plot contained 13 445 trees in 152 species and 11 200 lianas in 75 species. Twenty-eight per cent of trees supported lianas and the mean number of lianas per tree was 0.38 ± 0.72. Association analysis between lianas and trees of 16 tree families and 20 abundant tree species indicated that tree susceptibility to lianas was better pronounced at species rather than at family level. Overall, at Varagalaiar site, the aggregation of lianas followed neither Poisson nor clumped distribution. Among the four dominant tree families Dipterocarpaceae and Clusiaceae fit to the negative binomial model better than Euphorbiaceae and Meliaceae. These four families differed in their susceptibility level with 34.6% , 36.7% , 24.1% and 27.7% of trees ≥ 30 cm gbh respectively supporting lianas. At the species level, the proportion of trees with lianas was positively correlated with the mean branch free bole height of trees ≥ 30-40 and ≥ 40 cm gbh classes, and the mean number of lianas per tree was also positively correlated with the mean branch bole height of trees ≥ 30 cm gbh. Of the 16 abundant families, Euphorbiaceae contributed 31% and dominated the lower canopy, but its susceptibility to lianas was lower when compared to most other families.

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Ambient air characteristics of biogenic volatile organic compounds at a tropical evergreen forest site in Central Western Ghats of India

Journal of Atmospheric Chemistry ◽

10.1007/s10874-021-09415-y ◽

2021 ◽

Author(s):

Nidhi Tripathi ◽

L. K. Sahu ◽

Kashyap Patel ◽

Ashwini Kumar ◽

Ravi Yadav

Keyword(s):

Organic Compounds ◽

Western Ghats ◽

Ambient Air ◽

Evergreen Forest ◽

Forest Site ◽

Biogenic Volatile Organic Compounds ◽

Tropical Evergreen Forest ◽

Western Ghats Of India ◽

Volatile Organic ◽

Central Western Ghats

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Prey selection and food habits of the Tiger Panthera tigris (Mammalia: Carnivora: Felidae) in Kalakkad-Mundanthurai Tiger Reserve, southern Western Ghats, India

Journal of Threatened Taxa ◽

10.11609/jott.5607.12.5.15535-15546 ◽

2020 ◽

Vol 12 (5) ◽

pp. 15535-15546

Author(s):

Bawa Mothilal Krishnakumar ◽

Rajarathinavelu Nagarajan ◽

Kanagaraj Muthamizh Selvan

Keyword(s):

Western Ghats ◽

Prey Selection ◽

Scientific Information ◽

Distance Sampling ◽

Evergreen Forest ◽

Line Transect ◽

Panthera Tigris ◽

Tiger Reserve ◽

Tropical Evergreen Forest ◽

Southern Western Ghats

The Endangered Tiger Panthera tigris is the largest felid, distributed over 1.1 million km2 globally. Conservation of Tigers largely depends on the preservation of its natural prey base and habitats. Therefore, the availability of prey and its selection play a major role in the sustainable future of Tigers in the given landscape. The current study assesses the prey selection patterns by Tigers in tropical evergreen forest of the Kalakkad-Mundanthurai Tiger Reserve (KMTR), southern Western Ghats, India. Density of ungulates was assessed by distance sampling (line transect, N = 21) and diet composition of Tigers was evaluated by analysing their faecal samples (N = 66). The study estimated very low ungulate density (26.87 ± 7.41 individuals km-2) with highest density of Gaur Bos gaurus (9.04 individuals km-2) followed by Wild Boar Sus scrofa (8.79 ± 2.73 individuals km-2), whereas, primate density was quite high (45.89 ± 12.48 individuals km-2), with Nilgiri Langur Semnopithecus johnii having the highest density (38.05 ± 10.22 individuals km-2). About 74.62% of the biomass of Gaur constituted in the Tiger’s diet, consumed lesser than its availability, whereas Sambar constituted 16.73% of the Tiger diet consumed proportionally to its availability. Chital Axis axis, Muntjac Muntiacus muntjak, and Indian Chevrotain Moschiola indica were not represented in the Tiger’s diet. The current study is the first scientific information on prey selection of the Tiger in KMTR landscape, which will serve as a baseline for its conservation planning and management.

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Ischaemum mistryi (Poaceae: Andropogoneae): A new remarkable species from Sub-Tropical Evergreen Forest, India

Phytotaxa ◽

10.11646/phytotaxa.509.3.2 ◽

2021 ◽

Vol 509 (3) ◽

Author(s):

SHAHID NAWAZ LANDGE ◽

RAJENDRA D. SHINDE

Keyword(s):

New Species ◽

Detailed Comparison ◽

Iucn Red List ◽

Red List ◽

Evergreen Forest ◽

Short Discussion ◽

Iucn Red List Categories ◽

Tropical Evergreen Forest ◽

Sessile Spikelet ◽

A New Species

Ischaemum mistryi, a new species from the Sub-Tropical evergreen forest of Tilari Ghat, Maharashtra, India, is described and illustrated. This grass is unique with its leaves drooping, mostly congregated near the base, basal sheath villous, culms compressed at the base, lower glume of the sessile spikelet linear-lanceolate to oblongish tapering and slightly curled upwards, without a sub-apical ridge, nodules absent (if present 2–4 obscure) on its keels, and upper lemma of sessile spikelet bi-partite. Morphologically it is somewhat similar to I. mangaluricum, I. travancorense and I. barbatum. We provided a table of its detailed comparison with close species as mentioned above. According to IUCN Red List Categories and Criteria, we have assessed this new species as Critically Endangered (CR). The photo plates and illustration of the grass are given to facilitate its proper identification. A short discussion is also provided at the end.

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Effect of Disturbance Regimes on Spatial Patterns of Tree Species in Three Sites in a Tropical Evergreen Forest in Vietnam

International Journal of Forestry Research ◽

10.1155/2016/4903749 ◽

2016 ◽

Vol 2016 ◽

pp. 1-16 ◽

Cited By ~ 1

Author(s):

Do Thi Ngoc Le ◽

Nguyen Van Thinh ◽

Nguyen The Dung ◽

Ralph Mitlöhner

Keyword(s):

Spatial Patterns ◽

Tree Species ◽

Interspecific Interactions ◽

Abundant Species ◽

Evergreen Forest ◽

Small Scale ◽

Forest Types ◽

Disturbance Regimes ◽

Tropical Evergreen Forest ◽

Disturbed Forest

The effects of disturbance regimes on the spatial patterns of the five most abundant species were investigated in three sites in a tropical forest at Xuan Nha Nature Reserve, Vietnam. Three permanent one-ha plots were established in undisturbed forest (UDF), lightly disturbed forest (LDF), and highly disturbed forest (HDF). All trees ≥5 cm DBH were measured in twenty-five 20 m × 20 m subplots. A total of 57 tree species belonging to 26 families were identified in the three forest types. The UDF had the highest basal area (30 m2 ha−1), followed by the LDF (17 m2 ha−1) and the HDF (13.0 m2 ha−1). The UDF also had the highest tree density (751 individuals ha−1) while the HDF held the lowest (478 individuals ha−1). Across all species, there were 417 “juveniles,” 267 “subadults,” and 67 “adults” in the UDF, while 274 “juveniles,” 230 “subadults,” and 36 “adults” were recorded in the LDF. 238 “juveniles,” 227 “subadults,” and 13 “adults” were obtained in the HDF. The univariate and bivariate data with pair- and mark-correlation functions of intra- and interspecific interactions of the five most abundant species changed in the three forest types. Most species indicated clumping or regular distributions at small scale, but a high ratio of negative interspecific small-scale associations was recorded in both the LDF and HDF sites. These were, however, rare in the UDF.

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