Tropical forests serve as carbon sinks and perform an essential function in climate change mitigation. The present research paper seeks to assess the carbon storage ability of different tree biomass and vegetation soil and temporal soil carbon stock at Ramnabagan wildlife sanctuary in Burdwan, West Bengal. The four vegetation sites of deciduous trees species (Shorea robusta, Tectona grandis, Schleichera oleosa, and Albizia lebbeck) were selected for biomass estimation as well as carbon stock. The tree biomass was calculated using allometric equations, and litterfall was estimated by standard litter trap method. Soil parameters were analyzed using standard techniques. Results revealed that organic carbon content in top soil was higher than subsoil, whereas bulk density showed a reverse trends. The highest quantity of tree biomass was recorded for A. lebbeck followed by S. robusta, S. oleosa, and lowest for T. grandis. Moreover, the highest carbon stocks of biomass were noticed for A. lebbeck (1.96 t/ha) and leaf litter for S. robusta (0.60 t/ha). Carbon stocks in soil were highest for S. robusta (11.30 Mg/ha) in summer, A. lebbeck (14.72 Mg/ha) in rainy, and S. oleosa (17.02 t/ha) in winter seasons, respectively. The order of the total carbon storage capacity of different vegetation site was S. robusta > A. lebbeck > T. grandis > S. oleosa. Therefore, it was concluded that tree species conservation insights into the major biomass drivers and carbon storage of soil may contribute to climate change mitigate in the tropical forest.

The internal retranslocation of nutrients of senescence leaves is a significant aspect of nutrient dynamics in a forest ecosystems. The present investigation was carried out by considering four types of deciduous tree species (Shorea robusta, Tectona grandis, Schleichera oleosa, and Albizia lebbeck) to assess nutrient resorption efficiency (NuRE) and resorption proficiency (NuRP) of nitrogen (N), phosphorous (P), and potassium (K), as well as seasonal changes of nutrient concentration in green and senescence leaves. Green and senescent leaves were sampled and analysed for NPK concentration by standard methods. Experimental results revealed that the higher nutrition contents were recorded in green leaves than senescence leaves. The highest N and P resorption efficiency (RE) were recorded for S. robusta and lowest for T. grandis (46.74

The present study focused on the soil enzyme activities through in situ incubation of litter decomposition pits across major seasons in a subtropical forest of Bengal. This study examined the activities of extracellular enzymes (amylase, cellulase and invertase) and their relationship with the types of litter decay and soil physiochemical properties at different depths of the soil matrix. The higher decay constant ( k ) of decomposed leaf litter was recorded for Tectona and lower for Albizia in the studied three seasons. The results also revealed that the activities of soil extracellular enzymes were higher in rainy season compared to winter in all experimental sites with respect to control. Among the studied enzymes, invertase was significantly higher in different decomposed sites at the surface soils compared to other enzymes during the rainy season. The results also demonstrated that the enzyme activities gradually declined from the surface soil to subsurface soil at the different decomposed sites. However, in surface soil, the amylase and invertase activities were highest in Tectona litter-containing soil and cellulase activity was highest in Shorea litter-containing soil in all the studied seasons. On the other hand, soil parameters such as moisture, organic carbon and available nitrogen were significantly correlated with enzyme activities in different decomposed sites. The results suggest that the activity of the extracellular enzymes involved in litter decomposition varies in different species and seasons.

The present study evaluates the cytogenetic effects of both silver and gold nanoparticles on the root cells of Allium cepa. In this study, the root cells of Allium cepa were treated with both gold and silver nanoparticles of different concentrations (1 mg/L, 5 mg/L and 10 mg/L) along with control for 72 h. Experimental results revealed that after 72 h of exposure, a significant decrease in mitotic index (MI) from 68% (control) to 52.4% (1 mg/L), 47.3% (5 mg/L) and 41.4% (10 mg/L) for gold nanoparticles and 57.1% (1 mg/L), 53% (5 mg/l), 55.8% (10 mg/L) for silver nanoparticles. Through minute observation of the photograph, it was recorded that some specific chromosomal abnormalities such as stickiness of chromosome, chromosome breaks, nuclear notch, and clumped chromosome at different exposure conditions. Therefore, present results clearly suggest that Allium cepa root tip assay could be a viable path through which negative impact of both gold and silver nanoparticles can be demonstrated over a wide range of concentrations.

We studied leaf litter fall, decomposition and nutrient release patterns of Shorea robusta and Tectona grandis by using a litter bag technique to better understand the release pattern of nutrients to soil from leaf litter. Annual litterfall varied from 13.40 ± 2.56 t ha −1 a −1 for S. robusta to 11.03 ± 3.72 t ha −1 a −1 for T. grandis and the decay constant ( k ) of decomposed leaf litter was distinctly higher for T. grandis (2.70 ± 0.50 a −1 ) compared to S. robusta (2.41 ± 0.30 a −1 ). Biomass loss was positively correlated with the initial litter C, WSC, C/N and ash content in S. robusta and N, P and K concentration for T. grandis . Biomass was negatively correlated with lignin and L/N ratio for S. robusta and L, WSC, L/N and C/N ratio for T. grandis ( P < 0.01). Nutrient use efficiency (NUE) and nutrient accumulation index (NAI) of S. robusta was higher than for T. grandis . The retranslocation of bioelements from senescent leaves ranked as P > N > K. Annual N, P and K input to soil through litterfall differed significantly between the two species in the following order: N>K>P. S. robusta was superior in terms of K and P return and T. grandis was superior in terms of N return. The two tree species showed a similar patterns of nutrient release (K > P > N) during decomposition of their leaf litter. Nutrients of N, K and P were the primary limiting nutrients returned to soil through litterfall with important roles in soil fertility and forest productivity.

Soil enzyme activities provide a unique biochemical means for assessing soil function as an indicator of soil fertility, which can be altered by a profusion of fluoride in the soil and seasonal changes. Seven sites were chosen in the fluoride-affected area of Nasipur, Birbhum District, West Bengal, India, to compare seasonal changes in enzymes (urease, amylase, cellulase and invertase), fluoride content, physicochemical characteristics and the availability of microbes in the soil with a control. The activity of all the enzymes varied with season. Urease had greater activity in the summer, followed by winter; it showed marginal differences from the control area during the winter (p<0.002) and summer (p<0.110) but a significant (p<0.000) difference during the rainy season. Soil pH had a negative impact on urease activity during both winter and summer. Cellulase activity was accelerated by the organic matter and organic carbon content of the soil. Fluoride therefore had the greatest activity against urease activity during the rainy, summer and winter seasons. The microbial population of the soil also showed a negative impact of fluoride, which may in turn affect the soil enzymes and characteristics.

This study aims to check the tolerance potential of Solanum tuberosum to accumulate fluoride (F). For this work S. tuberosum were grown for 87 days under five different concentrations of F viz. control, 11.05(T1), 22.11(T2), 44.21(T3), 110.53(T4) and 221.05(T5) mg per Kg NaF. Study results revealed that maximum reduction of root biomass (82.5 %) at the fluoride dose 95 mg NaF/Kg soil. However, growth ratio and tolerance index showed opposite trend with concentration of F. On the other hand, F accumulation pattern was recorded highest in leaves and % of total F translocation from soil to plant linearly decreases with increasing added fluoride in soil. The F accumulation in leaves, root, shoot and potato tuber is 3.96 mg NaF per Kg, 3.02 mg NaF per Kg, 2.8 mg NaF per Kg and 1.56 mg NaF per kg, respectively. It was inferred from this study that potato (S. tuberosum) accumulates fluoride at tissues level.

Heavy metals are major environmental pollutant when they present in high concentration in soil and have toxic effects on growth, nodulation and nitrogen fixation of legumes and development of plants. Mercury stress triggers disturbances in cellular structure, and metabolismn is poorly understood. The response of seedling growth and nodulation of Vigna radiata (L) Wilczek to different concentrations (0.1, 0.5, 1.0 and 1.5 ppm) of mercury (Hg) salt solutions were studied. Morphological parameters like root and shoot length, dry weight, nodule number, total leaf area and biochemical constituents (chlorophyll, malondialdehyde and leghaemoglobin) of bean plants were recorded at an interval of 30 days. The successive growth deformaties in seedlings and nodules were recorded at lower concentration (0.1 ppm), but marginal (0.5 ppm) and higher (1.0 ppm) level of Hg salt solution showed significant suppression. The maximum level of Hg concentration (1.5 ppm) shows high level of tolerance index without any nodule. The control treatment shows maximum level of leghaemoglobin (0.219 mM) and all other morpho-physiological and bio-chemical properties of roots and shoots excepting tolerance index (0.00) and chlorophyll ‘a’ (7.52 mg g−1 FW). Mercury accumulation pattern follows the sequences: leaf > nodule > root ≈ shoot at lower level of Hg (0.1 and 0.5 ppm). However, higher level of Hg (1.0 and 1.5 ppm) showed shoot > root > leaf > nodule. The scanning electron microscopy (SEM) study of root also highlights the deleterious effect of Hg salt at higher concentration.

This paper presents a novel human-system collaborative robot-programming platform, where case-based reasoning (CBR) and explanation-based learning (EBL) are integrated together. CBR takes advantage of its unique CBR cycle to achieve the knowledge acquisition and reuse in the form of case, realizing efficient robot programming with the support of experienced human experts. EBL optimizes the rule structure in the knowledge base through learning in retrieving speedup rules in order to accelerate the case adaptation process. Feasibility of this proposal is verified via a number of experiments that allow the system to output both schemata for generalized robot programming tasks whose calculation rules are adaptive enough so that it can be applied to novel task inputs. Moreover, it is shown that our system is adaptive to the increase of the cases processed and be able to tackle with the learning utility problem.

A study has been conducted to observe the toxic effect of leachate from cigarette origin tobacco leaf and extracts of cigarette smoke on Bengal gram (Cicer arietinum L.). Results showed that germination index significantly vary with concentration. Almost all the treated seeds germinated within five days of incubation. However tobacco leaf extract showed 85 % germination with same days of incubation. The growth parameters like root length, shoot length, number of leaf per plant, shoot diameter, root and shoot fresh and dry weight etc. changes according the concentration gradient. The highest pigment content and germination index were recorded in treatment T4.

Six aquatic macrophytes, such as Pistia stratiotes, Ceratophyllum demersum, Nymphoides indica, Lemna major, Azolla pinnata,and Eichhornia crassipes were considered for remove fluoride from aqueous solution. Five different concentrations (10, 30, 50, and 100 ppm) of fluoride solution were taken in 1 L plastic container. Fixed weight (20 g) of macrophytes along with 500 ml fluoride solution was taken in each plastic container for 72 hours observation. Results demonstrated all the macrophytes show highest fluoride removal during 24 h to 48 h, but after 72 h their efficiency reduced drastically. The species N. indica showed better removal efficiency than other experimental macrophytes. In general, pigment measurement data indicated higher concentration at 72 h. However, Pistia sp. showed higher concentration of pigmentation at intermediate time interval (48 h). Higher level of dry weight to fresh weight ratio was recorded for L. major and A. pinnata at all concentrations, excepting at 10 ppm. In addition, all macrophytes showed lower RGR at higher concentration. Isotherm study indicated that macrophyte C. demersum is a good fitted with Freundlich and Langmuir isotherm whereas L. major with Langmuir isotherm during 24 hours.

An investigation was initiated to examine the effects of carbon soot collected from exhaust tube of 15 years old petrol and diesel operated vehicles on gram seed germination and biochemical changes of seedling. In view of the widespread cultivation of gram seed in India and long-term impact of black carbon is the warming of the atmosphere as per the recommendation of IPCC (2007). Black soot were separately treated with different doses and the effects of these treatment had on seed germination, seedling vigor, chlorophyll and carotenoid content, root and shoot growth, protein, sugar, phenol and proline estimation were studied. The treatment T6 significantly affected on seed germination (84%) as well as seedling vigor and chlorophyll content. But other treatment promoted both seed germination and seedling vigor along with enhancement of other biochemical constituents. On the other hand micrograph study revealed that treatments T1 and T4 both showed negative effects on stomata rather than the ultra-structure of xylem and phloem.

Seed germination, one of the most important phase in the life cycle of a plant, is highly responsive to the existing environment. High levels of heavy metals significantly change the structural orientation of leaf, root and shoot. This paper reports on the effect of Cd toxicity on seed germination, seedling growth, photosynthetic pigment content and structural orientation of vascular tissues in chickpea ( Cicer arietinum L) seedlings. Results showed that inhibition of seed germination and root growth started at 0.10 mM cadmium treatment solution and the highest inhibitive effect was found at 50.0 mM concentration. The accumulation of cadmium in plant parts are in the order root > stem > leaf. From the SEM study it was found that normal orientation of the vascular tissues as well as associated tissues are disrupted and the stomatal complexes with guard cells were highly affected in the leaves. Permanent URL: http://hdl.handle.net/2047/d20018674

In the present study adsorption of copper (II) ions from aqueous solution by alluvial soil of Bhagirathi River was investigated under batch mode. The influence of solution pH, sorbent dose, copper concentration, contact time, stirring rate and temperature was studied. The copper adsorption was favored with maximum adsorption at pH 6.0. Sorption equilibrium time was observed in 60 min. The equilibrium adsorption data were correlated with Freundlich, Langmuir, DubininRadushkevich, Temkin and BET adsorption isotherm models. The kinetics of the adsorption process was tested by pseudofirst-order, pseudo-second order, Elovich, Intra-particle diffusion and surface mass transfer models. It was shown that adsorption of copper could be described by the pseudo-second order kinetic model. The activation energy of the adsorption process (Ea) was found to be -17.63 kJ/mol by using the Arrhenius equation, indicating physisorption nature of copper (II) adsorption onto adsorbent. Thermodynamic parameters such as Gibbs free energy (G o ), the enthalpy (H o ) and the entropy change of sorption (S o ) have also been evaluated and it has been found that the adsorption process was spontaneous, feasible and exothermic in nature. The results indicated that alluvial soil of Bhagirathi River can be used as an effective and low-cost adsorbent to remove copper (II) from aqueous solution.

The objective of the present study was to access the pollutant generated from bio-fuels like bamboo sticks, cow dung, paddy straw, carbon dust cake, gobar gas, jute stick, and mustard stick and synthetic fuel like LPG during cooking in rural villages of Burdwan, West Bengal, India and its fluctuation in living room. The average SO2 released from the fuels was found in the following order: bamboo stick > cow dung > paddy straw > carbon cake > gobar gas > jute stick > LPG > mustard stick; NO2 emission was in the following order : mustard stick > carbon dust cake > paddy straw > cow dung cake > LPG, jute stick > gobar gas > bamboo stick > and SPM was obtained in the following sequence: cow dung cake > bamboo stick > carbon dust cake > gobar gas > LPG > mustard stick > paddy straw > jute stick, respectively. The highest living room to kitchen room (L/K) ratio of SO2, NO, and SPM was found in LPG, gobar gas, jute stick respectively in 2009 and followed by bamboo stick > paddy straw > jute stick > cow dung cake, respectively in 2010. Results of this study suggest that different fuels released different amount of air pollutants, but more extensive study is needed to confirm the relationship between fuels and released air pollutants.

The study was done to evaluate enzyme activities (amylase, cellulase and invertase) from the soils of different vegetation sites, with seasonal variation, of social forest, Burdwan, India. Study results showed significant lower enzymatic activities in the subsoil compared to those of the topsoil. The seasonal variations indicated that amylase, cellulase and invertase enzyme activities had reached peaks during the rainy seasons in different soil depths. Amylase activity was highest in Tectona litter containing soil in all seasons in both the soil layers. All the three enzyme activities have shown significant positive correlation with available nitrogen (p < 0.05) and available phosphorous (p < 0.05) during rainy season in both the soil depths. Correlation study revealed that soil organic carbon was positively correlated with cellulase and invertase activities except in the Anacardium vegetation site in the topsoil during rainy season. Irrespective of the seasons and the depths of soil, control site without vegetation showed much lower levels of organic carbon and enzyme activity compared to those of the experimental sites. Therefore, it is concluded that carbon transformation will be higher during rainy season in the vegetation sites of forest soil under such agroclimatic conditions.

The present study investigates that physiological response on gram seeds (Cicer arietinum L.) under treatment of different leaf leachate in laboratory conditions. The aqueous leaf leachate of seven variety of selected tree species viz. Acacia auriculiformis A. Cunn ex.Benth, Anacardium occidentale L., Albizia lebbeck(L)Benth, Eucalyptus citriodora Hook, Emblica officinalis Gaertn, Shorea robusta Gaertn.f., Tectona grandis Linn f was studied on physiological changes during gram seed germination. Aqueous extracts of tree species significantly reduced the frequency of seed germination, vigour index; shoot length, root length, fresh and dry weight. Plant pigment viz., chlorophyll, carotenoids reduced significantly. The soluble sugar content reduced with 100 %( v/v) of leachate treatment but proline and phenol content increased on the test plant. The result revealed that Eucalyptus citriodora. and Shorea robusta extract had greater inhibitory effect on germination and vigour index over the control due to the presence of allelochemicals in the leachate. Leachate biochemical analysis also supports the inhibitory effect of seed germination and biochemical effects of seedlings. Allelopathy, allelochemicals, proline, vigour index, carotenoids.

A new medium, eggshell powder has been developed for fluoride removal from aqueous solution. Fluoride adsorption was studied in a batch system where adsorption was found to be pH dependent with maximum removal efficiency at 6.0. The experimental data was more satisfactorily fitted with Langmuir isotherm model. The kinetics and the factor controlling adsorption process fully accepted by pseudo-second-order model were also discussed. Ea was found to be 45.98 kJmol-1 by using Arrhenius equation, indicating chemisorption nature of fluoride onto eggshell powder. Thermodynamic study showed spontaneous nature and feasibility of the adsorption process with negative enthalpy (∆H0) value also supported the exothermic nature. Batch experiments were performed to study the applicability of the adsorbent by using fluoride contaminated water collected from affected areas. These results indicate that eggshell powder can be used as an effective, low-cost adsorbent to remove fluoride from aqueous solution as well as groundwater.

A laboratory experiments was conducted for the assessment of physiological and biochemical responses of iron dust under the influence of different pH levels (6.5, 5.0, 3.0) and two concentration of iron dust (0.1 mg and 0.6 mg) with two particle size (100 μm and 300 μm) sprayed on the Cicer arietinum L. seed surface for fifteen day exposure. Observation was made on germination percentage and germination rate, vigour index, % phytotoxicity of root and shoot, chlorophyll, sugar, protein and proline content in both treated and control plant. The present results revealed that the seed color changes to brown under iron stress. The lower germination percentage and germination rate gradually decrease with pH of the medium but both the parameters were not significantly affected by the iron dust. Moreover higher % phytotoxicity was observed under all treatments compared to control and also lower values of this parameter were recorded in shoot than root. The reduction trend in chlorophyll and protein content was recorded at low pH but reverse result was recorded for sugar. Moreover highest proline was recorded under highly acidic condition.