Ravi Chaturvedi | Banaras Hindu University, Varanasi (original) (raw)

Papers by Ravi Chaturvedi

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

TDR/The Drama Review, 2002

ABSTRACT Plant functional traits (PFTs) are the characteristics of plant species which respond to... more ABSTRACT Plant functional traits (PFTs) are the characteristics of plant species which respond to the dominant ecosystem processes of the habitat. Tropical dry deciduous forests (TDFs) experience a long dry period annually; therefore, main focus should be on those functional traits (FTs) which make a species successful in relation to moisture gradient. TDFs are characterized by FTs like deciduousness and drought tolerance. Deciduousness is a phenological attribute expressing adaptation to seasonality and drought, resulting in minimized activities during the unfavourable season and resumption of growth with variable rates of resource use during the short favourable season. There is much diversity in FTs among various plant species and also within species due to the characteristics such as rooting depth and the degree of drought experienced by them. Since, the extent and intensity of seasonal drought in TDF may differ with the geographical location, there can be a mosaic of different functional types showing varying adaptations to seasonal drought. Information on PFTs related to morphological and physiological traits are lacking for the dry deciduous woody species of Vindhyan highlands. Therefore, proposed research was initiated with the following objectives: • To identify determinants of composition, distribution and diversity of woody species in the TDF of Vindhyan Highlands on the basis of moisture content (SMC) and other physico-chemical properties of the soil • To characterize selected PFTs of dry deciduous species in terms of morphological/physiological and soft/hard traits • To analyze the effect of SMC and other soil physico-chemical properties on the selected PFTs of the TDF • To group woody plants of TDF according to selected FTs To fulfil the above objectives, the work was done in five sites, Hathinala West (24º 18´ 07˝ N and 83º 05´ 57˝ E, 291 m.a.s.l.), Gaighat (24º 24´ 13˝ N and 83º 12´ 01˝ E, 245 m.a.s.l.), Harnakachar East (24º 18´ 33˝ N and 83º 23´ 05˝ E, 323 m.a.s.l.), Ranitali (24º 18´ 11˝ N and 83º 04´ 22˝ E, 287 m.a.s.l.) and Kotwa (25º 00´ 17˝ N and 82º 37´ 38˝ E, 196 m.a.s.l.) which are located in the Vindhyan highlands, India. The area experiences tropical monsoon climate with three seasons in a year, viz. summer (April to mid June), rainy (mid June to September) and winter (November to February). Soils are residual, ultisols derived from Kaimur sandstones (Dhandraul orthoquartzite), sandy-loam in texture (Raghubanshi 1992) and reddish to dark gray in colour and extremely poor in nutrients (Singh et al. 1989). This study emphasizes the relationship between morphological and physiological traits of the woody species and their effects on community organization and ecosystem processes. For the detection of the effect of plant species on the FTs at different habitats, analysis of species composition, distribution and diversity in the five experimental sites was done. Plants adjust leaf life-span so as to maximize whole-plant photosynthesis according to their deciduousness. Leaves from different plant species may have different carbon gain strategies and different life-spans. Therefore, the diversity of leaf life-span in the woody species of Vindhyan highlands was detected and the plant species were grouped according to their leaf flushing period, leaf life-span and leaf fall period. Seven morphological and twelve physiological traits were identified which are important for the plant species of the dry deciduous forest and their range in tree and shrub species across the experimental sites were observed. Further, analysis of the response of FTs to soil moisture content across species and sites was performed. The relationships among FTs and between FTs and soil properties across sites were also examined. Plant species were segregated across experimental sites on the basis of physico-chemical properties of soil. Grouping of plant species was also done on the basis of studied FTs. Six dominant and ubiquitous tree species were selected and a detail study of physiological traits was done at four sites, every month for two years to test the following hypotheses: (i) FTs of the tree species are influenced by SMC, (ii) there are variations in the relationships of the FTs among species at different SMC and in different seasons, (iii) growth traits are influenced by leaf traits which are in turn related to SMC and (iv) FTs and their plasticity are affected by habitat conditions. Important findings from the present work are following: 1. Species composition of a site experiencing disturbance is a cumulative outcome of differential responses of species to disturbance. Some species may tolerate the disturbance and others may disappear. Among the species dominating or codominating the adult tree vegetation, A. catechu, H. binata, L. parviflora, L. coromandelica and Z. glaberrima increased in importance value with enhanced level of soil moisture stress, indicating that their ability to tolerate soil…

Tropical Plant Research, 2016

We analysed the diversity of leaf life-span in the woody species of Vindhyan highlands and groupe... more We analysed the diversity of leaf life-span in the woody species of Vindhyan highlands and grouped the plant species according to their leaf flushing period, leaf life span and leaf fall period. We also studied the factors influencing the foliar phenology of the woody species. The study was conducted on five sites (Hathinala, Gaighat, Harnakachar and Ranitali) within the tropical dry deciduous forest in northern India. Leaf life-spans of the woody species were highly variable. About 67% species had peak of their leaf flush initiation during summer period (pre-rain leaf flushing) and rest species had their peak leaf initiation during rainy season (post-rain leaf flushing). The peak period of leaf flushing initiation at all the sites was May when 52% of the species initiated their leaf formation and the peak period of leaf flushing completion was August when 38% of the plant species completed their leaf formation. The peak period of leaf fall initiation in maximum species (54%) at all...

Forest Ecology and Management, 2015

We investigated vegetation characteristics, carbon density (CD) and carbon accumulation (CA) of t... more We investigated vegetation characteristics, carbon density (CD) and carbon accumulation (CA) of trees in mono-and multi-specific, Tectona grandis (Teak) and Shorea robusta (Sal) forest stands in a tropical dry region of India to address the following questions: (i) How are the mono-and multi-specific stands structured in terms of relative basal area of tree species? (ii) What are the levels of CD and CA in the stem component of tree species in the mono-and multi-specific stands? (iii) Which vegetation characteristics strongly account for the variations in CD and CA in the tree species in the mono-and multi-specific stands? We established 15 stands (six mono-and nine multi-specific stands), each having 4 ha area in the forest region. Total number of species across the stands was 46 belonging to 25 families. Average tree density ha À1 and stem basal area (BA, m 2 ha À1), across the stands were 522 and 11.1, respectively. Margalef's index of species richness (SR), Whittaker's index of species evenness (Ew) and Shannon-Wiener index (H 0) were greater at multi-specific stands compared to mono-specific stands. Average wood specific gravity (WSG) across species for the mono-specific (Teak) was greatest compared to the other categories. Across the mono-and multi-specific stands, WSG among species ranged between 0.47 and 0.79 g cm À3 , with 26.2% having WSG P 0.70 g cm À3. Across the plots in mono-and multi-specific stands, stem density showed positive correlation with BA and aboveground stem biomass (AGB). The associations of SR with Ew and H 0 , and Ew with H 0 were significantly positive. The AGB was positively associated with SR, Ew and BA. Repeated measures ANOVA indicated significant effects of year, stand and species for DBH, height and AGB. Average aboveground CD and CA across the stands were 136 t-C ha À1 and 5.3 t-C ha À1 yr À1 , respectively. Results of step-wise multiple regression indicated that across the stands, CD was influenced by BA and H 0 , and CA was affected by SR and BA. Principal component analysis exhibited strong association of CA and CD with multi-specific stands compared to mono-specific stands. Teak and Sal trees showed maximum CA per unit BA at multi-specific stand compared to mono-specific stand. These findings can be used by the forest managers to increase the carbon density and accumulation in Teak and Sal forests of India.

Forest Science, 2015

For accurate estimation of teak biomass, it is necessary to develop allometric models for differe... more For accurate estimation of teak biomass, it is necessary to develop allometric models for different stem diameter classes (D classes). In this study, we harvested teak trees in the tropical dry forest region of India in 10 D classes, measured biomass of foliage, branch, bole, and the total aboveground part, and developed regression models for the nondestructive estimation of foliage, branch, bole, and aboveground biomass with the help of wood density (), stem diameter (D), and plant height (H). Models used for the prediction of biomass of tree components were of the linear, logistic, Gompertz, and Chapman forms. These models explained more than 90% variability in the biomass of each component of teak. For foliage biomass only, the model with just D as the estimator exhibited greater R 2 and lower standard error of estimate and average deviation. For branch, bole, and aboveground biomass, the models including , D, and H had greater R 2 and lower standard error of estimate. Our study detected that logistic models are more appropriate for broad diameter ranges and linear models for small D classes. The regression models developed in our study can be applied separately for the 10 D classes, and this could minimize the error occurring during nondestructive estimation of biomass of teak in different D classes.

Journal of Sustainable Forestry, 2014

ABSTRACT We investigated the composition of tropical dry forest woody species at adult, sapling, ... more ABSTRACT We investigated the composition of tropical dry forest woody species at adult, sapling, and seedling stages, in terms of plant diversity, distribution, and importance value index (IVI), and identified the dominant and ubiquitous species in the five study sites having variable edaphic properties. Species varied markedly in the composition and IVI at different sites. The semi-evergreen species, Shorea robusta, was dominant at the wettest site at all the three growth stages; at the driest site, highly deciduous species Lannea coromandelica was the dominant adult species and Nyctanthis arbortristis the dominant sapling and seedling species. Soil moisture content (SMC) altered the distribution of about 8% of the adult species. ANOVA indicated significant site-wise differences in the Shannon-Wiener index, Whittaker’s evenness, Margalef’s species richness, and β-diversity for the woody species at all the three stages. The Shannon-Wiener index, Whittaker’s evenness, Margalef’s species richness, and β-diversity were greater in seedlings as compared to adult and saplings of tree species. These variations in species composition and distribution are evidently on account of different levels of SMC as well as habitat heterogeneity as indicated by β-diversity which was independent of SMC.

Environmental Monitoring and Assessment, 2015

Soils play an important role to describe the economical growth of the study area. Soils of low le... more Soils play an important role to describe the economical growth of the study area. Soils of low level flood plains near Varuna River, is very fertile in nature without adding any nutrient in it. The Varuna is a minor tributary of the Ganges and extended between 25°27' N to 82°18'E and 25°45' N to 82°3' E flows east to southeast from some of 100 km from Phulpur tehsil of Allahabad and joins the Ganges at 25°19' N 83°2' E and 25° 32' N 83° 44' E just downstream of Varanasi. Organic carbon present in sufficient amount in soils of low level flood plains. Macro nutrients viz., N, P, K and S govern the fertility of soils. Twelve representative villages are selected in the study area. The total study area of lower Varuna basin is around 23.05 sq km. and different number of soil samples (0-15cm) are collected and analyzed for their physical status and chemical property and also analyzed for macro nutrient like available nitrogen (N), phosphorous (P), potassium (K), and Sulphur (S) status. Soil samples were found low in available P while medium in organic carbon and available N and K. While about 86% samples were found deficient in available sulphur.

Tij S Research Journal of Social Science Management Rjssm, Aug 30, 2014

Journal of Plant Ecology, 2012

Tropical Plant Research

We developed allometric models for accurate estimation of Tectona grandis (teak) leaf area index ... more We developed allometric models for accurate estimation of Tectona grandis (teak) leaf area index (LAI), for different stem diameter-classes (D-classes). In this study, we harvested teak trees in the tropical dry region of India in the ten stem diameter classes and measured LAI, and developed regression models for the non-destructive estimation of LAI with the help of wood density (ρ), diameter at breast height (D) and plant height (H). Models used for the prediction of biomass of tree components were of the form, linear, logistic, Gompertz and Chapman. Among the four models, non-linear models were more efficient compared to the linear model. We observed more than 60% variability in the LAI, explained by non-linear regression models. The models including ρ and D had greater R 2 and lower standard error of estimate. Our study detected logistic models more appropriate for broad diameter range and Gompertz models for small D-classes. The regression models developed in our study can be applied separately for the ten D-classes, and this could minimize the error occurring during indirect estimation of teak LAI.

Proceedings of the Indian National Science Academy

India is home to an unusually large number of endemic species and ranks sixth among the 12 megabi... more India is home to an unusually large number of endemic species and ranks sixth among the 12 megabiodiversity centers of the world. Four terrestrial biodiversity hot spots (Himalaya, Indo-Burma, Western Ghats and Sri Lanka, and Sundaland) partly lie in India. The 27 distinct biogeographic provinces, and the variety of life zones and floral groups result in equally diverse vegetation and ecosystem types. The forest ecosystems are markedly diverse and have been classified into six 'major groups' ranging from tropical to alpine, 16 'groups' and more than 200 'group categories'. The grassland ecosystems are categorized into five major grass cover types. There are 1193 wetlands covering a total area of 3.9 million hectares in 274 districts. Total area of coral reefs comprises 2,375 sq km. India is one of the eight Vavilov's centers of origin of cultivated plants in the world and has twenty distinct agro-ecosystems, characterized by variations in edaphic, climatic and geographic features, and consequently a diverse cropping pattern. In this article we give an overview of the vast array of broad ecosystem types that occur in India. We also briefly discuss the human impacts on the health of country's ecosystems and the ecosystem conservation scenario.

ABSTRACT We analysed the phenotypic plasticity in nineteen functional traits (FTs) (seven morphol... more ABSTRACT We analysed the phenotypic plasticity in nineteen functional traits (FTs) (seven morphological and twelve physiological) in tree and shrub species across the five study sites located in a tropical dry forest (TDF), showing variable soil moisture content (SMC). The aim was to observe the range of FTs in tree and shrub species across the study sites. Further, the response of FTs to SMC across species and siteswas analysed. We also studied the relationships among FTs and between FTs and soil properties across sites. Results showed that the plasticity in FTs significantly varied across the study sites. The plasticity in FTs also differed significantly across species. All FTs under study affect relative growth rate (RGR) of the tree and shrub species directly or indirectly. However, the strength of effect is determined by environmental parameters and in case of TDF soil water availability is the important parameter. Plasticity in FTs due to changes in environmental parameters explained the variations in RGR. Step-wisemultiple regression indicates that more than 80% variability in RGR can be explained by canopy cover (CC), leaf area index (LAI), specific leaf area (SLA) and leaf intrinsic water use efficiency (WUEi) alone. First three variables represent quantity of photosynthetic surface and last represent water use economy of a species. All these are also significantly modulated by soil moisture availability. Important point to note here is that photosynthetic rate (A max) is not an important parameter to determine RGR in TDF where water economy and extended period of leaflessness are critical.

The Scientific World Journal, 2012

Accurate characterization of biomass in different forest components is important to estimate thei... more Accurate characterization of biomass in different forest components is important to estimate their contribution to total carbon stock. Due to lack of allometric equations for biomass estimation of woody species at juvenile stage, the carbon stored in this forest component is ignored. We harvested 47 woody species at juvenile stage in a dry tropical forest and developed regression models for the estimation of above-ground biomass (AGB). The models including wood-specific gravity (ρ) exhibited higher R 2 than those without ρ. The model consisting of ρ, stem diameter (D), and height (H) not only exhibited the highest R 2 value but also had the lowest standard error of estimate. We suggest that ρ-based regression model is a viable option for nondestructive estimation of biomass of forest trees at juvenile stage.

New Forests, 2013

ABSTRACT Estimation of accurate biomass of different forest components is important to estimate t... more ABSTRACT Estimation of accurate biomass of different forest components is important to estimate their contribution to total carbon stock. There is lack of allometric equations for biomass estimation of woody species at sapling stage in tropical dry forest (TDF), and therefore, the carbon stored in this forest component is ignored. We harvested 46 woody species at sapling stage in a TDF and developed regression models for the biomass esti-mation of foliage, branch, bole and the total aboveground part. For foliage and branch biomass, the models with only stem diameter as estimator showed greaterR 2 . For bole and aboveground biomass, the models including wood specific gravity or wood density exhibited higherR 2 than those without wood density. Also, the model consisting of wood density, stem diameter and height had the lowest standard error of estimate for bole and aboveground biomass. Moreover, theR 2 values are very similar among models for each component. The measurement error of height and the use of a standard value of wood density together may introduce more than 2 % error into the models. Therefore, we suggest using diameter-only model, which may be more practical and equally accurate when applied to stands outside our study area.

Journal of Biosciences, 2011

Functional traits (FTs) integrate the ecological and evolutionary history of a species, and can p... more Functional traits (FTs) integrate the ecological and evolutionary history of a species, and can potentially be used to predict its response as well as its influence on ecosystem functioning. Study of inter-specific variation in the FTs of plants aids in classifying species into plant functional types (PFTs) and provides insights into fundamental patterns and trade-offs in plant form and functioning and the effect of changing species composition on ecosystem functions. Specifically, this paper focuses on those FTs that make a species successful in the dry tropical environment. Following a brief overview, we discuss plant FTs that may be particularly relevant to tropical deciduous forests (TDFs). We consider the traits under the following categories: leaf traits, stem and root traits, reproductive traits, and traits particularly relevant to water availability. We compile quantitative information on functional traits of dry tropical forest species. We also discuss trait-based grouping of plants into PFTs. We recognize that there is incomplete knowledge about many FTs and their effects on TDFs and point out the need for further research on PFTs of TDF species, which can enable prediction of the dynamics of these forests in the face of disturbance and global climate change. Correlations between structural and ecophysiological traits and ecosystem functioning should also be established which could make it possible to generate predictions of changes in ecosystem services from changes in functional composition.

Forest Ecology and Management, 2012

We investigated the effect of grazing and harvesting on diversity, mortality, recruitment and car... more We investigated the effect of grazing and harvesting on diversity, mortality, recruitment and carbon accumulation of juvenile trees at five sites in a tropical dry forest (TDF) to address the questions: (i) How is the TDF structured in terms of juvenile trees and their carbon densities? (ii) What is the level of biotic disturbances in the TDF which affect juvenile tree population? And (iii) what is the relationship between species mortality and recruitment in the sites having different disturbance intensities? Across the sites, we recorded juvenile individuals in 41 species belonging to 22 families. Wood specific gravity (WSG) among species varied between 0.36 and 0.66 g cm À3. Carbon density in the juvenile tree populations ranged from 271 to 966 kg-C ha À1 and carbon accumulation from 10 to 210 g-C cm À2 yr À1. Mortality due to browsing, harvesting, and drought was respectively, 41%, 47% and 12%. Significant differences across sites were observed for species richness, carbon density, carbon accumulation, numbers of dung pellets and damaged juveniles, annual mortality index (AMI) and annual recruitment index (ARI). Species also differed significantly for AMI and ARI. Species richness, carbon density and carbon accumulation were negatively related with AMI and positively with ARI. Soil moisture content, total N and total P across study sites also favored juvenile recruitment. The findings suggest that mortality of juvenile trees in TDF is mainly due to browsing and harvesting. The future floristic composition and carbon accumulation of TDF will depend upon the status of juvenile trees. Therefore, it is important to restrict the livestock grazing in the forest and to particularly protect the juveniles of the dominant canopy trees and those with high carbon accumulation potential.

Environmental Monitoring and Assessment, 2013

Your article is protected by copyright and all rights are held exclusively by Springer Science+Bu... more Your article is protected by copyright and all rights are held exclusively by Springer Science+Business Media B.V.. This e-offprint is for personal use only and shall not be selfarchived in electronic repositories. If you wish to self-archive your work, please use the accepted author's version for posting to your own website or your institution's repository. You may further deposit the accepted author's version on a funder's repository at a funder's request, provided it is not made publicly available until 12 months after publication.

Abbreviations A area = Area-based photosynthetic rate (mmol m À 2 s À 1); A mass = Mass-based pho... more Abbreviations A area = Area-based photosynthetic rate (mmol m À 2 s À 1); A mass = Mass-based photosynthetic rate (nmol g À 1 s À 1); Chl = Chlorophyll concentration (mg g À 1); Gs area = Area-based stomatal conductance (mol m À 2 s À 1); Gs mass = Mass-based stomatal conductance (mmol g À 1 s À 1); LCC = Leaf carbon concentration (% dry wt.); LNC = Leaf nitrogen concentration (% dry wt.); LPC = Leaf phosphorus concentration (% dry wt.); RGR = Relative growth rate (cm 2 Á cm À 2 Á yr À 1); SLA = Specific leaf area (cm 2 g À 1); SMC = Soil moisture content (cm 3 cm À 3 expressed as % volumetric SMC); TDF = Tropical dry forests; WUEi = Intrinsic water use efficiency Nomenclature: