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Community structure and species diversity of Saddle Peak forests in Andaman Island

Authors:
K. P. Tripathi at Dolphin Institute of Bio-Medical & Natural Sciences, DEHRADOON, INDIA
K. P. Tripathi
  • Dolphin Institute of Bio-Medical & Natural Sciences, DEHRADOON, INDIA
S. TRIPATHI
S. TRIPATHI
S. TRIPATHI
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Thiru Selvan at Tripura University
Thiru Selvan
K. KUMAR
K. KUMAR
K. KUMAR
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Abstract

Saddle Peak forests, declared as a National Park, in Diglipur forest division of north Andaman (13°15′ to 13° 41′ N and 92° 37′ to 93° 7′ E) are characterized as humid tropical evergreen forests. A few species like Aglaia andamanica, Artocarpus gomeziana, Bombax insignie were common in all the studied sites. Among species, in littoral forests Mimusops littoralis, Artocarpus gomeziana, and in inland forest Pterocymbium tinctorium, Taberneamontana crispa, were dominant. In foothill forest Artocarpus chaplasa, Mallotus peltatus (male), were abundant whereas in middle saddle peak forest area Zanthoxylon budrunga, Parishia insignis and Mesua ferrea were the most abundant species. Across the sites the population density increased from 459 to 2681 plants per hectare from littoral to middle saddle peak forest site, but the reverse was true for basal area which decreased from 74 to 48 m2 ha-1. The species richness (61) as well as Shannon Wiener’s diversity index (3.58) were highest in foothill forest. Beta diversity was maximum in inland forest (5.1) and minimum in middle saddle peak forest (1.54). Heterogeneity was almost similar in foothill and middle saddle peak forests and it was relatively less in littoral forest zone. Mean girth showed a decreasing pattern from littoral forest (183) to middle saddle peak forest (39) similar to basal area. Size variation was greatest in foothill forest site showing a highest degree of asymmetry. Population structures for different forests have been prepared and interpreted.
Species diversity in Andaman Isla
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... Uniyal et al. (2010) reported Simpson's index of dominance to be 0.24 and 0.35 for managed and unmanaged forests respectively in Garhwal Himalaya. Tripathi et al. (2004) found Simpson's index of dominance for undisturbed forest between 0.041 to 0.126. This study also showed Simpson's index of dominance for the unmanaged block was 0.109 which is similar to the previous study however it was found higher for the managed blocks. ...
... However, Shannon-Wiener indices were nearly equal for disturbed (3.5) and undisturbed (3.4) evergreen forests of Andaman Island (Rasingam and Parathasarathy 2009). In the protected (undisturbed) forest of the same island, Tripathi et al. (2004) reported the Shannon Wiener index from 2.63 to 3.58. ...
Regeneration Status and Diversity under Irregular Shelterwood System: A Study from Panchkanya Community Forest, Sunsari, Nepal
Article
Full-text available
  • Jan 2021
The present study is the outcome of vegetation sampling conducted in the managed and unmanaged forest patch under the irregular shelterwood system to analyze community structure and plant diversity in a degraded mixed forest in Eastern Terai, Nepal. Systematic random sampling was followed by laying out 15 quadrates sized 4m2 with uniform spacing of 50 meters in both managed and unmanaged blocks, respectively. This study revealed that the first and second-year regeneration felling subsisted the Shorea robusta in the managed forest patch. There was observed a remarkable increase in regeneration but a decrease in plant diversity in the managed area in comparison to the unmanaged one. Simpson’s index of diversity was 0.760 and 0.890 and Shannon-Wiener indexes were 1.82 and 2.43 in managed and unmanaged forest blocks, respectively. Independent sample t-test showed a significant difference in the total number of regenerations between managed and unmanaged forest blocks since P-value <0.05 (P=0.0166) i.e., managed blocks with opened canopy had higher regeneration but a lower diversity. This study concludes that the irregular shelterwood system is deemed pivotal for increased regeneration of Shorea robusta particularly in the eastern lowland of Nepal.
... Tree diversity described by the Shannon-Wiener index showed a variation between 0.76 and 3.01 with a mean value of 2.05 ± 0.07 from homegardens of Sri Lanka (Mattson et al. 2015). Shannon-Wiener index of diversity of the current study (2.73) could be compared with tropical forest index values (2.6-4.8) for the Indian sub-continent as observed by many investigators (Visalakshi 1995;Tripathi et al. 2004). This confirms that diversity of homegarden is close to, although not as high, those of forest ecosystems even though it differs with function (Mohan 2004). ...
... The diameter distribution of tree density (number of trees) has often been used to represent the stand structure of a forest as well as a complex agroforestry system (Khan et al. 1987). As observed in many other studies especially from forest areas, the pattern of diameter class distribution of number of trees descending exponentially with increasing dbh is considered to be the major indicator of species with continuous regeneration (Tripathi et al. 2004). Although very little information exists in the regeneration dynamics of homegardens, Kumar et al. (1994) study from Kerala revealed a slightly skewed (positive) distribution pattern having the maximum number of trees in the 20-30 cm dbh class indicating the adequate regeneration of homegarden species. ...
Unveiling tree diversity and carbon density of homegarden in the Thodupuzha urban region of Kerala, India: a contribution towards urban sustainability
Article
  • Dec 2021
The present study aimed to assess the role of homegarden (HG) in safeguarding the tree diversity and carbon (C) density or storage in the Thodupuza urban region of Idukki district in Kerala, India. A stratified random approach was used for selecting the four homegardens (HGs) with a size of 1hectare (ha). The study mainly focused on species richness, diversity, above ground biomass, carbon, correlation and distribution of carbon with various variables, species and group wise carbon storage of the system. A total of 992 trees from 66 species belonging to 31 families were enumerated with representation of 4 endemic, 1 vulnerable, 1 endangered and 23 exotics. The diversity indices obtained were closer to those of the forest ecosystem. Above ground biomass and carbon density were estimated to be 67.06 t/ha (tonne/hectare) and 31.85 6 t/ha respectively. Species Tectona grandis showed dominancy in carbon and Important Value Index. Correlation analysis among species revealed that carbon exhibited a strong positive trend with basal area and tree density, but in the case of plot (HG)-wise examination only basal area had a strong positive relationship. The diametric class analysis showed skewed type of distribution for carbon and tree density while diversity had reverse j-shaped curve. Among the two plant groups, cultivated species had an edge over native in storing carbon. Overall, this assessment shows the potential of using homegardens as a socio-ecological systems for sustainable development particularly in terms of land availability and climate mitigation options in the face of rapid urbanization.
... However, Shannon-Wiener indices were nearly equal for managed (3.5) and non-managed (3.4) evergreen forests of the Andaman Island region (Rasingam & Parathasarathy, 2009). In the managed forests of the same island, Tripathi et al. (2004) reported a ShannonWiener index from 2.63 to 3.58. ...
... The Evenness (e) refers to the distribution pattern of the individuals between the species in the community. Importance Value Index (IVI) was calculated by summing up relative frequency, relative density, and relative dominance values in a particular stand (Tripathi et al. 2004). ...
Effects of Soil Management Practices on Soil Physical Properties and Water Cycle in a Multifactorial Field Experiment
Chapter
  • Sep 2021
In the last few decades, Bengaluru’s rapid urban expansion and associated population growth brought about profound changes in farming practices, reflected in an increase in irrigated land compared to rainfed land and a growing use of mineral fertilizers. Since it is not clear how intensification of land use due to urbanisation is affecting physical soil properties and field water cycle, we attempt to clarify this at two experimental sites established at the University of Agricultural Sciences Bangalore (UASB). The results show higher bulk densities, lower air capacities, and lower saturated hydraulic conductivity (Ksat) values in the rainfed field compared to the irrigated field. Soil moisture was observed to be higher in deeper layers of several plots with low N-level treatments in both experiments. However, it was not significant in other plots. Further statistical investigations and comparisons especially of model simulations are required to assess the effect of land use intensifications. Here the experimental approach and some preliminary results are presented.
... The Evenness (e) refers to the distribution pattern of the individuals between the species in the community. Importance Value Index (IVI) was calculated by summing up relative frequency, relative density, and relative dominance values in a particular stand (Tripathi et al. 2004). ...
Tree Species Diversity in the Southern Transect Across the Rural–Urban Interface of Bengaluru
Chapter
  • Sep 2021
Urbanisation is a complex process, differently defined in different contexts and disciplines. However, a general feature of urbanisation is that it comes along with changing environmental landscapes by accommodating large numbers of migrants and industries in densely built-up areas. This affects environmental and ecological components of the landscape. Trees have many ecological and environmental functions, as they provide habitat and protection for fauna and flora, and support spiritual, cultural and recreational activities of people. Our study addresses the composition, density and diversity of trees in the urban, transitional and surrounding rural region South of Bengaluru, India. WorldView-3 satellite imagery was used to randomly select 25 one-hectare plots with a high share of built-up area to characterize the tree species composition. A total of 82 tree species were observed in these plots, out of which 21 species were found in all the three domains. Diversity indices such as Shannon Index, Simpson Index, Pielou’s Evenness, and Margalef’s Richness indicated that tree species richness decreased towards the rural domain though the species composition varied from plot to plot. The Shannon and Simpson Index decreased towards the transitional and rural domain. The species were more or less evenly distributed in all domains.
... Shannon-Wiener DI. Shannon-Wiener DI is being widely used in several previous ecological studies (Lande, 1996;Laurin et al., 2014;Tripathi et al., 2004;Yeom and Kim, 2011). With the increase in the number of species and consistency in the species, the value of this index also increases (Kim et al., 2017;Lemos et al., 2011;Magurran, 2013) which indicates it is a measure of abundance and consistency. ...
Optimal band characterization in reformation of hyperspectral indices for species diversity estimation
Article
Full-text available
Species diversity quantification is a crucial step towards the conservation of biodiversity and healthy ecosystem. The technological advancements and existing limitations of multispectral remote sensing has increased the popularity of hyperspectral remote sensing which found its use in the estimation of species diversity. The contiguous narrow bands available in hyperspectral data enables the improvised assessment of diversity index but the overlapping of the information could result in the redundancy that needs to be handled. Due to this, the idenfication of optimal bands is very important and hence the current study provides modified hyperspectral indices through detection of optimum bands for estimating species diversity of Shoolpaneshwar Wildlife Sanctuary (SWS), India. Narrow hyperspectral bands of EO-1 Hyperion image were screened and the best optimum wavelength from visible and Near Infrared (NIR) regions were identified based on coefficient of determination (r²) between band reflectance and in situ measured species diversity. For in situ species diversity measurements, quadrat sampling was carried out in SWS and different Diversity Indices (DIs) namely the Shannon Weiner DI, Margalef DI, McIntosh DI and Brillouin DI were calculated. The identified optimum wavelengths were then employed for modifying 38 existing spectral indices which were then investigated for testing their relation with the in situ DIs. The obtained optimum bands in visible and NIR were found to be in variation with four DIs. During validation, mMNLI, mREPI, mSIPI and mRGRI were identified as the best hyperspectral indices for determining Shannon Weiner DI, Margalef DI, McIntosh DI and Brillouin DI respectively.
... Patterns of regeneration of juvenile (pole-sized) trees after early-stage mortality may provide strong signals of future shifts in composition, but these trends are yet to be examined in the region. Evergreen forests are associated with higher tree, bird and butterfly diversity and higher tree basal area (Davidar et al., 2001;Padalia et al., 2004;Prasad et al., 2010;Tripathi et al., 2004), making their conversion to deciduous patches a matter of concern. ...
Varying impacts of logging frequency on tree communities and carbon storage across evergreen and deciduous tropical forests in the Andaman Islands, India
Article
The majority of Earth's tropical forests have been selectively logged; some on repeated occasions. Selective logging is known to affect forest structure, composition and function in various ways, but how such effects vary with logging frequency and across forest types remains unclear. In the Andaman Archipelago in India, we examined adult and pole-sized trees in baseline (unlogged since 1990s), once-logged (logged between 2007 and 2014) and twice-logged (logged in early 1990s and between 2007 and 2014) evergreen and deciduous forests, and tested whether higher logging frequency was associated with lower canopy cover, tree density, tree diversity, aboveground carbon stocks and divergence in species composition, including increased relative abundances of deciduous species in these forests. While once-logged evergreen and deciduous forests were similar to their respective baselines for most attributes assessed, and twice-logged evergreen forests had 22-24% lower adult tree density and diversity, twice-logged deciduous forests had 17-50% lower canopy cover, pole density, adult species diversity and above-ground carbon stocks, and 12% higher deciduous fractions compared to the base-lines. Collectively our results reveal lasting impacts of repeated selective logging, even at relative low intensity, on tree communities and carbon storage. These impacts can potentially be mitigated by reducing logging frequency and retaining unlogged patches in logged landscapes, but management must also incorporate hetero-geneity in responses and recovery across different forest types. In the Andaman Islands, all forests may require more than 15-25 years between logging events, with deciduous forests potentially requiring more stringent extraction limits compared to evergreen forests.
... In the present study Simpson's index value range from 0.76-0.9 in undisturbed forest and 0.76-0.87 in disturbed forest stands. These values are well within range for other tropical forests (Knight 1975;Visalakshi 1995;Tripathi et al. 2004;Lalfakawma Sahoo et al. 2009;Selvan 2014). Further, greater species diversity indices in undisturbed forests indicate higher species richness and dominance of one or two species in the tree community. ...
Tree species diversity and biomass carbon assessment in undisturbed and disturbed tropical forests of Dibru-Saikhowa biosphere reserve in Assam North-East India
Article
Full-text available
In the present study, the tree species phytosociological attributes, tree density, basal area, and tree biomass carbon (above- and below-ground) distribution pattern was explored in the undisturbed and disturbed forest sites in Dibru-Saikhowa biosphere reserve of Assam, northeast India. The study area is globally recognized biodiversity hotspots in India and situated in the flood plain of the Brahmaputra and Lohit River. The tree species attributes like tree density, basal area, and tree biomass carbon were estimated in three undisturbed and disturbed forest sites. Principal component analysis, redundancy analysis, and correlation analyses were conducted to explore the relationship between biodiversity indices, forest stands characteristic, and tree biomass. The undisturbed forest stand showed the highest biological attributes (29–39 species and 25–33 genera) compare to disturbed forest stands (27–32 species and 21–27 genera). Combretaceae, Lauraceae, Phyllanthaceae, Salicaceae, Myrtaceae, and Moraceae has shown a higher importance value index. The biodiversity indices were significantly higher in undisturbed forest stands and the Shannon–Wiener diversity index (H′) ranged from 1.97 to 3.57, Simpson index (Cd) ranged from 0.76 to 0.88, and evenness index (e) ranged from 0.65 to 0.97 in all the stands. The mean tree density and forest basal area were significantly higher in the undisturbed forest (796.66 ha−1 and 56.56 m2 ha−1, respectively) compared to disturbed forest stands (436.66 ha−1 and 38.91 m2 ha−1, respectively). Tree biomass carbon in undisturbed forest (184–214.62 Mg C ha−1) was also more than disturbed forests (124–137.53 Mg C ha−1). Moreover, the biomass carbon was greatly affected by the tree composition, diversity, density, and the disturbances in forest stands. The present study will provide the baseline information for effective and sustainable tree species diversity conservation and evaluate tree carbon stock in the Dibru-Saikhowa biosphere reserve.
... These values of beta diversity indicates that species composition with increasing altitude varied considerably. Beta diversity values reported by Tripathi et al. (2004) ranged from 1.54 to 5.1. Sharma et al. (1999) recorded 1.11 to 2.4 values of beta diversity for Trikuta Hills (Jammu). ...
Ethnobotany of the Jarawa tribe of Andaman Islands, India (with an appendix on typifications and taxonomic notes)
Book
Full-text available
  • Nov 2020
Ethnobotany of the aborigine Jarawa tribe inhabiting the Andaman Islands, India is presented based on the studies carried out during 2001–2002 and 2018–2019. Ethnobotanical uses of 172 plant species used by the Jarawa tribe are documented in this presentation. They include: Marine algae: 2 families, 2 genera, 2 species. Pteridophytes: 1 family, 1 genus, 1 species. Gymnosperms: 2 families, 2 genera, 2 species. Angiosperms: 57 families, 136 genera, 167 species (Monocotyledons: 9 families, 29 genera, 48 species. Dicotyledons: 48 families, 107 genera, 119 species). The book is documented with 65 photographic Plates. Some of the earlier compiled publications on the plants used by the Jarawa tribe are marred by inaccuracies. Such inaccurately reported uses of 68 plant species are enumerated separately in a Table with references and appropriate notes and comments. The introductory part deals with the location, area, origin, geology, climate, soil types, vegetation, and the forest types of the Islands. A chapter has been added about the aborigine tribes and the settlers of the Islands. Botanical history of the Islands is then discussed followed by historical notes, review of literature on the economic botany, ethnobotany and anthropological studies. Background of the present studies and the materials and methods adopted are also elaborated. Next, the available details of the Jarawa tribe, such as origin, language, social aspects, age-sex ratio, movement, dietary pattern and storage of food, hygienic practices and common diseases and morbidity are mentioned with references. Finally, the ethnobotany of the tribe is presented followed by notes on impact of human interference and concluding remarks. The book is appended with a chapter on typifications and taxonomic notes. It is hoped that this presentation will be helpful for the researchers and students of botany, taxonomy and ethnobotany with reference to the Andaman Islands, India.
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Article
Full-text available
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Full-text available
  • Nov 1995
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Article
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Article
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Article
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Article
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Puerto Rico
Article
Puerto Rico. ELENA CEVALLOS. World Bibliographical Series, Volume 52. Oxford: Clio Press, 1985. xiii+195 pp. $40.00 (cloth). ISBN 0-903450-89-5
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Old-growth forests in the Pacific Northwest are known to support high levels of diversity across the varied landscapes they occupy. On 1200 plots distributed over the Cascade Mountains in southwestern Washington, climatic, physiographic, edaphic and floristic data were collected to evaluate the ecological characteristics of these coniferous forests and develop a classification framework useful in land management. The resulting abundance of data provided a unique opportunity to analyze plant diversity relationships at multiple levels and identify the environmental and biotic factors which influence diversity at local and landscape scales. Plant species richness and diversity were generally lower in communities characterized by environmental extremes (i.e., excessive or scarce moisture and severely cold high elevation) than in mesic environments at low-to-middle elevations. Evenness among plant species was greatest at higher elevations, where severe climate limited the ability of any single or group of species to dominate. Species turnover rates were also higher near the environmental extremes. High turnover rates among mountain hemlock associations were attributed to highly variable topography and local microclimates which resulted in substantial geographical isolation and species specialization among site types. Moisture appeared to have the most influence on species richness (alpha diversity) and sequential turnover rates (beta diversity) at high elevations, where available water is seasonally limited by low temperatures. Temperature had the greatest influence on overall species turnover (gamma diversity) throughout the landscape. Species richness of the landscape (epsilon diversity) was quite accurately predicted (within 7% for temperature and moisture gradients) by a computational method which uses independent measures of alpha, beta and gamma diversity. Patterns of forest plant diversity appear to be the result of environmental conditions at larger scales and the complex interactions among biological and physical variables at smaller scales, within an historical context of stochastic disturbance events. Managers wishing to restore and sustain the high diversity characteristic of these old-growth coniferous forests will need to consider the respective roles of various biophysical factors and the disturbance dynamics in these unique ecosystems.