Total Amount Of Carbon Research Articles

Efficient Sn Recovery from SnO2 by Alkane (CxHy=2x+2, 0\u2009\u2264\u2009x\u2009\u2264\u20094) Reduction

We study the mechanism of alkane reduction of SnO2 for efficient low-temperature recovery of Sn from SnO2. Based on thermodynamic simulation results, we comparatively analyze the reduction behavior and the efficiency of SnO2 reduction by H2 and alkanes (CxHy=2x+2, 0 ≤ x ≤ 4). We found that alkanes (n·CxHy) with the higher nx generally complete the reduction of SnO2 (T100) at the lower temperature. Moreover, the T100 of the SnO2 reduction by alkanes (n·CxHy) was decreased from the T100 of pure hydrogen with the same amount of hydrogen atoms (n·Hy). We found that the concentration of a gas phase product mixture, the amount of the produced solid carbon, and the T100 complementary vary as a function of the nx and ny, the total amount of carbon and hydrogen atoms in the reducing gas phase molecules. Our results demonstrate a viability of the low temperature reduction method of SnO2 by alkanes for efficient recovery of Sn from SnO2, which can be applied for Sn recovery from Sn containing industrial wastes or Sn ores with economic value added that is held by the co-produced H2.

ENSO-driven CO2 efflux variability and the role of the upwelling region on the carbon exchange in the Northern Humboldt Current System

Abstract The role played by El Nino-Southern Oscillation (ENSO) on modulating the oceanic carbon outflux in the Northern Humboldt Current System (NHCS) is assessed with the use of outputs from a coupled physical-biogeochemical hindcast which permits to evaluate the interannual variability of the surface seawater partial pressure of carbon dioxide, hereinafter pCO 2 s w , and reconstruct associated air-sea CO2 fluxes from 1998 through 2015 at monthly timescales. In addition, surface dissolved inorganic carbon (DIC) concentrations were inferred from a recent neural network methodology prescribed with the same outputs of the biogeochemistry hindcast. Results show a large spatiotemporal variability of the CO2 exchange to nine El Nino and La Nina episodes throughout the period of analysis. Within the coastal and equatorial upwelling region, that variability results from combined ENSO-driven ΔpCO2 (pCO 2 s w - pCO 2 a i r ) and wind speed variations, although the latter in a minor proportion during ENSO peaks. Specifically, it is found that the weak CO2 source behavior during an average El Nino episode is mainly caused by a weakening of ΔpCO2 which is partially compensated by more efficient CO2 exchange at the air-sea interface due to the strengthening of the upwelling-favorable winds. Conversely, the relatively strong CO2 source behavior during an average La Nina episode results from more efficient upwelling which brings colder but CO2-rich waters to the surface, therefore, increasing pCO 2 s w and the associated CO2 efflux. Moreover, it is estimated that during an average La Nina episode, 3.3 million metric tons of carbon is additionally emitted contributing to the atmospheric CO2 accumulation. In contrast, during an average El Nino episode, the total amount of carbon retained is about 24.7 million metric tons of carbon that normally would have been lost to the atmosphere as CO2, rendering the NHCS a key region for the global atmospheric carbon budget.

Strengthening mycorrhizal research in South America.

Strengthening mycorrhizal research in South America.

Re-assessing Vegetation Carbon Storage and Emissions from Land Use Change in China Using Surface Area

Land surface area estimation can provide basic information for accurately estimating vegetation carbon storage under complex terrain. This study selected China, a country dominated by mountains, as an example, and calculated terrestrial vegetation carbon storage (VCS) for 2000 and 2015 using land surface area and traditional ellipsoid area. The land surface area is estimated by a triangular network on the high precision digital elevation model. The results showed that: 1) The VCS estimated by the surface area measurement in 2000 and 2015 were 0.676 and 0.692 Pg C (1 Pg = 1015 g) higher than the VCS calculated using the ellipsoid area, respectively. 2) As the elevation increases, the differences between VCS estimated by surface area measurement and ellipsoid area measurement are expanding. Specially, a clear gap was present starting from an elevation of 500 m, with the relative error exceeds 8.99%. 3) The total amount of carbon emitted due to land use change reached 0.114 Pg C. The conversions of forestland and grassland to other land use type are the main reasons of the loss of vegetation carbon storage, resulting in a total amount of biomass carbon storage decreased by 0.942 and 0.111 Pg C, respectively. This study was a preliminary exploration of incorporating land surface area as a factor in resource estimation, which can help more accurately understand the status of resources and the environment in the region.

Comparative analysis of the physicochemical, phytochemical and mineral composition of avocado (Persea americana mill.) pulp and seed

An analysis on Some Physicochemical, Phytochemical and Elemental Composition of Avocado (Persea americana Mill.) Pulp and Seed were carried out. Avocado fruit is a tropical fruit and is one of the most productive plants per unit of cultivated area. Avocado stands out for its high nourishing value and its usefulness to growth and development. It has also been the subject of intense and varied use in the past not only for its importance in food but also for medicinal needs. The length, thickness, width, roundness, sphericity, mass, true density, bulk density, porosity, angle of repose, static coefficient of friction were all investigated. Moisture contents of 78.39±0.17% and 57.65±0.27% (DB) for the pulp and seed was determined respectively which revealed that the seed contained more of moisture than fat and fibre. The pulp of avocado has the highest content of all proximate analysis considered except in carbohydrate where the seed has 12.71±3.41. It was stated that the pulp has the highest amount of total carbon of 83.20±0.014%. These values were analyzed using AOAC methods. The pulp of the avocado proved to be rich in Saponins (0.15±0.02mg/100g), phenolic compounds (3.04±0.11mg/100g), 0.13±0.02 mg/100g Tannins, 0.01±0.00 mg/100g Cyanogenic glycosides, 0.15±0.00 mg/100g Alkaloids, 2.08±0.19 mg/100g Steroids, 5.11±0.11 mg/100g Phytates and flavonoids (4.05±0.12mg/100g). The seed was superior to the pulp in the contents of all phytochemical compounds with 18.91±2.01mg/100g of Saponins, 7.00±1.18 mg/100g of total phenols, 0.26±0.22mg/100g Tannins, 0.04±0.02mg/100g Cyanogenic glycosides, 0.70±0.12mg/100g Alkaloids, 7.00±1.18mg/100g Phenols and 44.3±3.1 mg/100g of flavonoids but lesser in steroids and phytates with 0.08±0.00mg/100g and 3.31±0.19mg/100g respectively. This research work was carried out in the Nutrition Laboratory, Department of Animal Production and Health. Federal University of Technology, Akure, Nigeria.

Organic Carbon and Nitrogen Stocks Along a Thermokarst Lake Sequence in Arctic Alaska.

Thermokarst lake landscapes are permafrost regions, which are prone to rapid (on seasonal to decadal time scales) changes, affecting carbon and nitrogen cycles. However, there is a high degree of uncertainty related to the balance between carbon and nitrogen cycling and storage. We collected 12 permafrost soil cores from six drained thermokarst lake basins (DTLBs) along a chronosequence north of Teshekpuk Lake in northern Alaska and analyzed them for carbon and nitrogen contents. For comparison, we included three lacustrine cores from an adjacent thermokarst lake and one soil core from a non thermokarst affected remnant upland. This allowed to calculate the carbon and nitrogen stocks of the three primary landscape units (DTLB, lake, and upland), to reconstruct the landscape history, and to analyze the effect of thermokarst lake formation and drainage on carbon and nitrogen stocks. We show that carbon and nitrogen contents and the carbon‐nitrogen ratio are considerably lower in sediments of extant lakes than in the DTLB or upland cores indicating degradation of carbon during thermokarst lake formation. However, we found similar amounts of total carbon and nitrogen stocks due to the higher density of lacustrine sediments caused by the lack of ground ice compared to DTLB sediments. In addition, the radiocarbon‐based landscape chronology for the past 7,000 years reveals five successive lake stages of partially, spatially overlapping DTLBs in the study region, reflecting the dynamic nature of ice‐rich permafrost deposits. With this study, we highlight the importance to include these dynamic landscapes in future permafrost carbon feedback models.

Evaluation of Carbon, Nitrogen and Phosphorus in Disturbed and Intact Tropical Coastal Forest Sites in Tanzania

This study investigated and established the variation of soil nitrogen, total carbon and phosphorus across closed forest; crop-agriculture and livestock disturbed sites. The study provides useful information for local management strategies. It sets initial basic data on the soil status of Uzigua Forest Reserve after 50 years of crop-agriculture and livestock grazing pressure. Forty-seven (50 m × 50 m) quadrats were established on each land uses for soil samples collection. Total nitrogen was analyzed by Kjeldahl acid-digestion, total carbon by the Walkley-Black procedures and phosphorus by Bray-II method. The mean values (percentage) were nitrogen = 16.07 ± 0.34, 1.75 ± 0.25, 6.5 ± 0.20; carbon =14.48 ± 0.23, 11.81 ± 0.13, 12.24 ± 0.30; phosphorus =14.12 ± 6.57, 17.74 ± 3.96, and 13.31± 2.86 for closed forest; agriculture disturbed and grazed sites respectively. There was a slightly lower amount of total carbon on crop agriculture disturbed sites than on the livestock grazed land uses. Carbon-nitrogen ratio was higher in closed forests than in the disturbed sites. The relationship between forest degradation and soil nutrient status is an indication that the below-ground nutrient pools are mainly determined by activities, which disturb the above-ground components mainly vegetation. To restore soil fertility status, it is important to establish the management of the disturbed sites through restoration of vegetation and minimization of disturbances.

Carbon sequestration during core formation implied by complex carbon polymerization

Current estimates of the carbon flux between the surface and mantle are highly variable, and the total amount of carbon stored in closed hidden reservoirs is unknown. Understanding the forms in which carbon existed in the molten early Earth is a critical step towards quantifying the carbon budget of Earth's deep interior. Here we employ first-principles molecular dynamics to study the evolution of carbon species as a function of pressure in a pyrolite melt. We find that with increasing pressure, the abundance of CO2 and CO3 species decreases at the expense of CO4 and complex oxo-carbon polymers (CxOy) displaying multiple C-C bonds. We anticipate that polymerized oxo-carbon species were a significant reservoir for carbon in the terrestrial magma ocean. The presence of Fe-C clusters suggests that upon segregation, Fe-rich metal may partition a significant fraction of carbon from the silicate liquid, leading to carbon transport into the Earth's core.

Valuing urban green spaces in mitigating climate change: A city-wide estimate of aboveground carbon stored in urban green spaces of China's Capital.

Urban green spaces provide manifold environmental benefits and promote human well-being. Unfortunately, these services are largely undervalued, and the potential of urban areas themselves to mitigate future climate change has received little attention. In this study, we quantified and mapped city-wide aboveground carbon storage of urban green spaces in China's capital, Beijing, using field survey data of diameter at breast height (DBH) and tree height from 326 field survey plots, combined with satellite-derived vegetation index at a fine resolution of 6m. We estimated the total amount of carbon stored in the urban green spaces to be 956.3 Gg (1 Gg=109 g) in 2014. There existed great spatial heterogeneity in vegetation carbon density varying from 0 to 68.1MgCha-1 , with an average density of 7.8MgCha-1 . As expected, carbon density tended to decrease with urban development intensity (UDI). Likely being affected by vegetation cover proportion and configuration of green space patches, large differences were presented between the 95th and 5th quantile carbon density for each UDI bin, showing great potential for carbon sequestration. However, the interquartile range of carbon density narrowed drastically when UDI reached 60%, signifying a threshold for greatly reduced carbon sequestration potentials for higher UDI. These findings suggested that urban green spaces have great potential to make contribution to mitigating against future climate change if we plan and design urban green spaces following the trajectory of high carbon density, but we should be aware that such potential will be very limited when the urban development reaches certain intensity threshold.

Annual respiration of Japanese mud snail Batillaria attramentaria in an intertidal flat: its impact on ecosystem carbon flows

The Japanese mud snail Batillaria attramentaria, a common gastropod in northeastern Asia, often predominates in isolated or degraded intertidal flat ecosystems in Japan and in other countries where it has invaded as an alien species. To evaluate the effects of B. attramentaria on carbon flow in intertidal flat ecosystems, we estimated the annual respiration of B. attramentaria from field surveys and laboratory experiments. The densities of the snails, as determined at an intertidal flat of the Seto Inland Sea, western Japan, were 235–485 individuals m−2. Temperature and snail size strongly affected their respiration rates, as determined by measuring their CO2 emission rates using an open-flow infrared gas analyzer method. The respiration rates were higher in the submerged condition than in the air-exposed condition. Based on the size structure of the natural population, laboratory experiment results, and environmental factors in the field (temperature and duration of the ebb/flood tide), we estimated the respiration in spring, summer, and autumn, respectively, as 1.9, 2.4, and 4.0 g C m−2. The total amount of carbon mineralized annually by the respiration of B. attramentaria exceeds 10% of that mineralized through sediment respiration. Based on these data and respiration/ingestion ratios in previous reports, we conclude that B. attramentaria has a significant impact on the carbon flows in intertidal flat ecosystems.

The effect of the ink composition on the performance of carbon-based conductive screen printing inks

Conductive carbon-based screen printable inks are used in a wide range of applications. The aim of the comprehensive study was to monitor how the fundamental components affect the ink performance. In the present work there were prepared several variants of carbon-based inks. The higher ratio of carbon black in the graphite (G):carbon black (CB) mixture, and also the higher total carbon amount have been confirmed to cause an increase in viscosity in the shear rates range from 200 to 1000 s−1. The lowest sheet resistance values were observed with 3:1 G:CB ratio. Increasing of the total carbon amount from 15 to 35 wt% has led to improvement in conductivity with final value of 32.4 Ω sq−1. The increasing ratio of lower boiling point solvents (4-hydroxy-4-methyl-2-pentanone, ethyl alcohol) has led to the improvement of the sheet resistance (lowest value of 22.73 Ω sq−1), while the roughness values increased. In the case of rheological properties evaluation, the ethyl cellulose content modification (increase from 2 to 10 wt% in the binder) resulted in increasing viscosity dependencies. In addition, the increase of the ethyl cellulose content had minimal impact on the roughness, but positive impact on the conductivity. On the other hand, it was identified an unobvious trend after modifying the binder by polyvinylpyrrolidone. To achieve the desired effect on the sheet resistance, volume resistivity and roughness of the printed layers it is necessary to specify the most proper ethyl cellulose:polyvinylpyrrolidone ratio. The main reason is the interaction between the two polymers within the binder.

PHYSICAL FRACTIONS OF GRAY FOREST SOIL OF VLADIMIR’S OPOLE AND ITS RELATIONSHIP WITH CROP PRODUCTIVITY OF AGRICULTURAL CROPS

In the physical fractions of gray forest soil (agroseraya typical): clay (up to d = 0.001 мм), light (lighter than 2 g/cm3) and the residue fraction, the contents of total carbon and phosphorus (total, organic and mineral forms) were determined. We have found that fertilizing increased the content of total carbon in the soil after 20 years of rotation system. Content of light fractions also increased. Mineral fertilizers reduced the content of organic carbon in the light fractions of this soils, this effect requires further study. The application of lime and manure reduced the content of clay fraction, but increased the content of total carbon in it. The yield of cereals and perennial grasses depended little on the amount of total carbon in the soil and its clay and light fractions. In this case, its feedback is established with the content of light fraction and carbon in the residue. The yield of grain crops is proportional to the proportion of mineral phosphates and weakly dependent on organic forms in the subsurface horizon. In general, the yield of cereals increases with the application of mineral fertilizers. The effect of manure was less pronounced.

Carbon Sequestration Potential of Macrophytes and Seasonal Carbon Input Assessment into the Hokersar Wetland, Kashmir

Wetlands are the most effective terrestrial carbon sinks as their vegetation has high gross primary productivity. Species specific efficiency of wetland macrophytes for sequestering carbon, however, has not been studied well. This study highlights the carbon sequestration efficiency of twelve abundant macrophytes in Hokersar Wetland, Kashmir, India. The total dry biomass and the carbon (C) content were higher in post-summer than summer and winter seasons. In the selected macrophytes, C content was higher in the above-ground (AG) component than in the below-ground (BG) one. Among the twelve species studied, the C in the total dry biomass of Phragmites australis was highest followed by Sparganium erectum and Typha angustata. It was estimated that a total amount of carbon sequestered by twelve macrophytes was 0.85 Kg C m−2 yr.−1 of which marginal emergent macrophytes sequestered 0.73 Kg m−2 yr.−1, rooted floating types 0.08 Kg m−2 yr.−1 and submerged macrophytic species 0.042 Kg m−2 yr.−1 in Hokersar wetland ecosystem. This study will be helpful to refine our understanding about the role of macrophytes in carbon sequestration of wetlands and could also be explored in earning carbon credits in the global carbon market.

Waste Biomass as in Situ Carbon Source for Sodium Vanadium Fluorophosphate/C Cathodes for Na-Ion Batteries

This work presents a series of electrode materials constituted by a sodium vanadium fluorophosphate as the electroactive phase and an in situ generated carbon derived from waste biomasses as carbon source. The waste biomasses consist of grounded vine-shoots, eucalyptus wood, and sucrose as control sample. The materials were obtained by hydrothermal carbonization during the hydrothermal synthesis followed by a flash thermal treatment (FTT). This way, carbonaceous matter decomposes into hydrochar while the electroactive phase is formed under autogenous pressure at 170 or 200 °C. The electrochemical tests were performed by adjusting the electrode composition to a total carbon amount of 20 wt %, so that the suitability of the in situ carbon as conductive additive was evaluated. Electrochemical performance was significantly improved after an FTT treatment. Among the biomass-based materials, samples that had the highest amount of the in situ generated carbon, resulting from eucalyptus biomass, showed the best e...

Aluminothermic reduction of ZrSiO4 in the presence of carbon for in situ formation of Zr-based silicides/carbides composites

Aluminothermic reduction of ZrSiO4 in the presence of carbon was investigated in the SHS (self-propagating high-temperature synthesis) manner. PTFE was employed not only as a reaction promoter to ensure self-sustaining combustion and improve the reduction of ZrSiO4, but as a carburizing agent to take part in carbide formation. The combustion wave velocity and temperature increased with increasing PTFE content, but decreased with carbon. Based on a correlation between combustion temperature and velocity, the activation energy Ea = 180.4 kJ/mol was deduced for the PTFE-activated ZrSiO4/Al/C reaction. According to the XRD and EDS analyses, the phase composition of the synthesized product depended on the total amount of carbon. The SHS reaction produced Al2O3-added Zr-silicides (ZrSi2 and ZrSi)/carbides (ZrC and SiC) composites. With an increase in carbon, the dominate phase was transferred from silicides to carbides. A further increase in carbon led to in situ formation of the ZrC/SiC/Al2O3 composite. The study confirmed ZrSiO4 as a source for the production of zirconium silicides, ZrC, and SiC.

CNP Ratio and Dose Regulated Production of Water Chestnut Trapa: Social and Environmental Implications

Water chest nut Trapa is a minor fruit crop and potential carbon sequester of atmospheric carbon. Mass production of water chest nut using a vast number of unused small water bodies and derelict waters is a win-win-win-win strategy toward mitigation of global warming, nutritional security, empowerment and resource utilization. Growth performance of Trapa was conducted in small culture units using different CNP ratios (25:02:01; 101:08:01; 290:01:01) at a fixed dose (0.2 kg/tank) of mixed manure with different doses (100, 200, 400, 600 g) of optimal CNP ratio (101:08:01) during the life cycle of Trapa. The total number of fruits and the wet weight of Trapa in different dose treatments ranged from 56 to 192 and from 258 to 379 g/tank. Yield of Trapa remained maximum when CNP ratio was 101:8:1 at 200 g/tank and the dosage was 200 g/tank with the optimal CNP ratio (134 g) and then declined with further rise in fertilizer dose. The proximate analysis of Trapa revealed the highest phosphorus content in all the tissues (fruit, leaf, and root) of Trapa grown in the CNP ratio of 101:08:01. Of the total amount of carbon in Trapa, contribution was maximum by the fruit (38–41%), followed by leaf (27–35%) and root (23–32%) in different ratio treatment. The C content of harvested Trapa grown in different CNP ratios (Table 4) was higher in fruit (38–41%) followed by leaf (27–35%) and root (23–32%) among tissues. The amount of C observed in control (32%) increased by 6% in 25:02:01 (34%) which was higher than remaining two treatments (31%). Dry weight or total carbon content of water chestnut tended to rise with increasing levels of phosphate of water from the dosage of 100 to 200 g with optimal CNP ratio and declined thereafter. A direct relationship between the dry weight or carbon content of Trapa and the total carbon content or phosphate to total carbon ratio of water was established. However, the carbon content remained between 27–32% in all the three tissues of Trapa culture when cultured in different dose treatments. It is reasonable to conclude that water chestnut may be promoted for mass cultivation using the recommended culture protocol that would help trapping atmospheric carbon, provide nutritional security and employment generation and resource utilization.

XANES-Based Quantification of Carbon Functional Group Concentrations.

X-ray absorption spectroscopy in the soft X-ray range is used in many research fields to identify the nature of functional groups in organic compounds and carbon materials. However, the concentrations of these functional groups have so far remained difficult to quantify. Using X-ray absorption near edge structure (XANES) spectra of reference materials (polymers and compounds of known molecular composition), we established a correlation between measured optical densities and functional groups concentration. This methodology relies on an alternative method for normalization to the total amount of carbon and for deconvolution of the spectra. It allows precisely quantifying the N/C atomic ratio (σ1 = 0.02 atom %) as well as the concentration of [aromatic + olefinic] groups (σ1 = 3.7 atom %), [ketone + phenol + nitrile] groups (σ1 = 2.2 atom %), [aliphatic] groups (σ1 = 11.2 atom %) and [carboxylic] groups (σ1 = 7.4 atom %). We validated this quantification by comparing with nuclear magnetic resonance data obtained on pyrolized lignin samples. We also provide an easy-to-use python program automating XANES-based quantification of carbon functional group concentrations.

Accessing unconventional biofuels via reactions far from local equilibrium

The thermochemical production of fuels from lignocellulosic biomass is constrained by equilibrium thermodynamics. However, low temperature plasma reactions are not governed by local equilibrium and involve the formation of unique radical and ion species. Thus, low temperature plasma can open pathways in the conversion of lignocellulosic biomass to products not observed in conventional thermochemical processing. In this effort, a novel radio-frequency (RF) plasma-enhanced fluidized bed reactor was utilized for the low temperature plasma deconstruction of lignocellulosic biomass in a hydrogen background gas. Of the reacted biomass in the plasma, 35% of the carbon was converted into hydrocarbons. Specifically, 16.9, 8.2, 9.6, and 0.2% of the reacted carbon from the biomass was converted into CH4, C2Hx, C3Hx, and C4Hx, respectively. With increasing power input, more rapid conversion of biomass was achieved, while the total amount of carbon from the biomass converted into hydrocarbons was similar.

Seasonal and inter-annual variability of soil CO2 efflux in a Norway spruce forest over an eight-year study

Automated soil CO2 efflux chamber measurements were carried out over a period of eight years in a young Norway spruce forest in the northeast region of the Czech Republic to determine seasonal and inter-annual variables affecting this flux. The data obtained was summarized and analysed with the aims of estimating long-term carbon losses from the soil and comparing selected models to determine the model best describing soil CO2 efflux. Our results show that seasonal variation in soil CO2 efflux was driven mainly by soil temperature, while inter-annual variation showed the closest relationship with precipitation. The total amount of carbon released from the soil into the atmosphere per season varied from 6.4 to 11.2 tC ha−1 over the eight-year record. One of the variables used in the CO2 efflux models, beside environmental variables, was day of year (DOY). Incorporating this variable into models improved the estimation of soil CO2 efflux dynamics. Therefore, we assume that models incorporating DOY could be used effectively to gap-fill measured soil chamber data. These models could also be appropriate for filling longer gaps on a scale from days to weeks, because DOY, as a single parameter, covers up to 80% of variability in the data. This study also demonstrated the different levels of correlation between investigated climate variables and soil CO2 efflux at seasonal and inter-annual time scales. This highlights the importance of different environmental variables in interpreting long-term soil CO2 efflux data and also modelling the complexity of the processes connected with soil CO2 efflux in Norway spruce forest.

Allometric Relationships for Biomass and Carbon Estimation of Neem (Azadirachta indica A. Juss) Plantations in Dryland of Hyderabad, Telangana

The present study was conducted in Central Research Institute for Dryland Agriculture (CRIDA), Hyderabad to develop the allometric equations for predicting the total biomass and carbon of Azadirachta indica in three different basal diameter classes (0–10 cm, 10–20 cm and 20–30 cm). The growth variables viz., tree height, basal diameter, DBH, crown height and crown width are maximum for neem under higher diameter class, whereas minimum under lower diameter class. The average total biomass of neem tree was recorded as 122.3 kg/tree and 338.8 t/ha in all three diameter classes. The allometric relationship between the variables in Azadirachta indica was highly significant with positive and high correlation. The highest and significant linear relationship was observed in tree height (0.992) followed by crown height (0.963) with above ground biomass. With below ground biomass, a strong and highly significant relationship was observed in tree height (0.988) followed by crown height (0.974) and DBH (0.967). The above ground variables (tree height, basal diameter, DBH, crown height and crown width) had highly significant linear relationship with predicted variable of total biomass. The highest and strongest coefficient observed between total carbon and tree height (0.991) followed by crown height (0.968) and DBH (0.957). And also, the significant relationship was found between the dependent variable (total carbon) and other independent variables viz., basal diameter (0.821), and crown width (0.910). Therefore, the result of this study may be useful to predict the amount of total carbon and biomass stored in Azadirachta indica plantation on area basis.