Loading...
Theses
Browse
7 results
Search Results
ThesisItem Open Access Effects of Conservation Tillage and Herbicide Application on Soil Microbial Activity in Rice-Mustard Sequence(AAU, Jorhat, 2019-07) Parit, Rajat Kumar; Mahanta, KaberiThe study on the “Effect of Conservation Tillage and Herbicide Application on Soil Microbial Activity in Rice-Mustard sequence”in the year 2018-2019 which forms a part of the long term trial under AICRP on Weed Management that was established during 2016 at Instructional-cum-Research (ICR) farm of Assam Agricultural University. The experiment was laid out in randomized block design replicating three times with five treatments in winter rice and mustard crop separately. The treatments of winter rice was comprised of treatments viz., T1- CT (Conventional tillage)+ Transplanting, T2- CT+Transplanting+ Pretilachlor, T3- CT+ Direct Seeded +Pretilachlor, T4- MT (Minimum tillage)+ Direct Seeded +Pretilachlor and T5- MT+ Direct Seeded+ Residue +Pretilachlor. Similarly, the treatments of mustard crop was comprised of treatments viz., T1-CT, T2- MT+ Pendimethalin, T3- CT+ Pendimethalin, T4- MT+ Residues+ Pendimethalin, T5- MT+ Residues+ Pendimethalin.The physical and chemical properties viz., bulk density, porosity, water holding capacity, pH, CEC and available nutrients viz; nitrogen, phosphorus, potassium, calcium, magnesium and soil organic carbon were determined from surface soil samples collected after the harvest of both winter rice and mustard crop. Conservation tillage i.e. MT along with residue has improved soil physical properties like bulk density, porosity, water holding capacity and CEC except the pH of the soil did not vary significantly. The soil organic carbon content increased significantly due to MT, herbicide application and residues. Available nitrogen, phosphorus, potassium, calcium and magnesium content of the soil was recorded in the medium range with highest available nitrogen, phosphorus, potassium, calcium and magnesium content recorded in the treatment T5 receiving MT+ Residues+ Herbicide Application in both winter rice and mustard crop. Biological parameters were analysed from surface soils collected periodically at 0, 3, 7, 15, 30, 45, 60 DAA of the herbicide in both winter rice and mustard crop. After the study, MT was found to improve the major enzymatic activities, soil microbial biomass carbon, physicochemical properties, available nutrients and soil organic carbon content as compared to conventional tillage (CT). Application of pretilachlor in winter rice showed a decline in β-glucosidase and urease activity for first 15 DAA and then increased till harvesting. However, a stimulatory effect was observed on activity of acid phosphatase, dehydrogenase and microbial biomass carbon for short period of time which later on decreased. Application of pendimethalin in mustard caused a decrease in dehydrogenase and β-glucosidase in initial stage while it increased the activity of acid phosphatse, urease and microbial biomass carbon in initial stage. Regarding the effect of herbicide application on available nutrients and soil organic carbon content it showed a stimulatory effect on these parameters. Significantly higher enzyme activities were recorded in treatments T5 which was comprised of MT+ Residues+ Herbicide Application.ThesisItem Open Access Ecological Occurrences of Methylotrophs in Phyllosphere of crops(AAU, Jorhat, 2019-07) Phukan, Sanghamitra; Gayan, AnjumaThe phyllosphere is an ecologically important habitat that hosts a large and diverse microbial community. Bacteria are among the most abundant inhabitants of the phyllospheric leaf surface, where the conditions are very harsh, due to heat, irradiation, rainfall, etc. The present investigation envisages the isolation, biochemical characterization and screening of phyllosphericmethlyotrophic bacteria associated with various crops for their plant growth promoting characteristics. Methylotrophs are a group of microorganisms that have the ability to utilize C1 compounds such as methanol or formaldehyde along with several multi carbon compounds, the most common genera being Methylobacterium, comprising mostly of pink pigmented facultative methylotroph (PPFM). In the present investigation leaf samples were collected from different crops comprising of five sites of Jorhat district, Assam. Leaf being the dominant aerial part, was considered for isolation purpose. Following the leaf imprinting and serial dilution technique, isolation of phyllopshericmethylotrophic bacteria were carried out. Eighteen isolates were screened for their plant growth promoting traits like Indole acetic acid (IAA), siderophore production, antibiotic resistance, ammonia production, etc. All the isolates produced IAA within a range of 0.69- 5.53 μg g⁻¹, with the highest in spinach (M16). The total nitrogen content of the isolates ranged between 1.4- 2.6 mg g⁻¹. Siderophore production was shown by the isolates M1 (chili) and M10 (cauliflower) and resistance to common antibiotics was also shown by few isolates, isolate M4,M15, M16 and M 17 from ivy gourd, cowpea, spinach and french bean crops respectively. Isolates M1, M10 and M12, retrieved from the phyllopshere of chilli and cauliflower crop possessed the ability to solubilize phosphorus, and isolate M7 from phyllosphere of tomato could solubilize zinc. After screening for plant growth promoting traits, twelve isolates were finally selected for a series of biochemical tests. All the isolates could hydrolyze casein, but none could hydrolyze starch. Catalase test was positive for all the isolates but all isolates did not possess cytochrome c oxidase enzyme. Few isolates M1, M4, M7, M10, M15, M16, M17 from chilli, ivy gourd, tomato, cauliflower, cowpea, spinach and frenchbean showed nitrate reduction. The isolate M13 showed positive urease activity. Citrate utilization was seen only in case of one isolate from phyllosphere of french bean (M17). Few isolates could show positive results for indole and VogesProskauer’s test but methyl red test was positive for one isolate from phyllosphere of chillicrop. Enumeration of methylotrophic bacterial population carried out for both phyllosphere samples and rhizospheric soil, resulted in a higher population in the phyllosphere. Soil samples of the study site were also analyzed for soil chemical (pH, available N, available P2O5,available K2O, organic carbon) and biological parameters (microbial biomass carbon, fluorescein diactetate, phosphomonoesterase). Correlation studies between the population of methylotroph in leaf and that of rhizospheric soil resulted in positive correlation (r=0.762*). Phyllospheric population of the methylotrophic bacteria and soil pH of the study sites also resulted in a positive correlation(r=0.934**). From the research initiative, it could be inferred that a wide array of methylotrophic bacteria occur in the phyllosphere of different crops, and possess plant growth promoting traits. These phyllosphericmethylotrophic bacteria could further be utilized for coinoculation with biofertilizers or used as bioinoculantsin crop improvement.ThesisItem Open Access EFFECT OF NUTRIENT MANAGEMENT ON PHOSPHORUS TRANSFORMATION AND ITS INFLUENCE ON YIELD OF BELL PEPPER (Capsicum annum) UNDER PROTECTED CULTIVATION(AAU, Jorhat, 2019-07) Dutta, Arindam Kumar; Tamuly, DanishThe present investigation entitled "Effect of Nutrient Management on Phosphorus transformation and its influence on yield of Bell pepper (Capsicum annum) under protected cultivation was carried out in the Horticulture Farm of AAU, Jorhat- 13. The experiment was conducted maintaining Split-split design having three(3) factors(Nitrogen, Phosphorus and Potassium) and each having three (3) levels(N- 80,100,120 P-40,60,80 K-40,60,80) accounting for a total treatment combination of twenty seven (27) having replicated thrice(3). Small portion of soils was collected from different treatments under protected cultivation at a depth of 0-15 cm. The soil samples were collected at two different stages of the crop viz., flowering and fruiting stages i.e 45 and 115 DAP respectively and was analyzed for different physico-chemical properties. The initial study revealed that the texture was silty loam with a bulk density of 1.176g cm-3 and the particle density 1.18 Mg m-3. Organic C (%) was found in the high range (0.94%) with a CEC of 13.7 cmol(p+) kg-1 of soil. The soil was acidic with a pH value of 5.32. Soil was having initial NPK content i.e 535.66 kg ha-1, 36.25 kg ha-1 and 68.56 kg ha-1 respectively. The present study revealed that the single factor effect of treatment has a significant effect on soil chemical properties, plant nutrient partitioning and various forms of P, except for Residual P which was found to be non-significant. The interaction effect of NP found to be significant with the physico-chemical parameters .The NP interaction with plant nutrient partitioning found that the highest values (3.383%,1.365%N and 0.385,0.366%P) of leaf and shoot nitrogen and phosphorus content are obtained in the higher dose of nutrients(N120P80) and highest value in leaf and shoot K(4.996% and 4.126%) are found in low to medium dose of fertilizer in the flowering stage but in the fruiting stage, higher values are obtained in the medium dose of NP levels . NP interaction with different forms of P is also found to be significant and the highest values are obtained in medium to high dose of fertilizer (N-100,120 and P-60,80). Available P and exchangeable Ca and Mg were found to be high in the low level of NK interaction. The leaf and shoot N and K content tends to increase with the increase level of NK fertilizers. Various forms of P were found to be high in the low to medium level of NK interaction (N-80,100 and K-40,60). For PK interaction, Available N was found to be highest (766.5 kg ha-1) in the low to medium dose of PK and available P2O5 & K2O were found to be high in higher level of treatments (P80K80). CEC was found to be non-significant in the flowering stage but found to be significant in the Fruiting stage. Similar results were found as in NK interaction with the plant nutrient partitioning i.e high NPK leaf and shoot content were found in the medium to high level of PK. Different forms of P were also found to be significant with the PK interaction and the highest values were observed with the higher dose of P. In the Interaction effect of NPK, all the physico-chemical properties are found to be significant. The plant nutrient partitioning and the various forms of P, except for Residual P were also found to be significant with the interaction effect of NPK. The present study suggested that the nutrient management was found to influence the physico-chemical properties of the soil as well as various forms of P, except for Residual-P. The different forms of P were found to poorly explain the yield variability and did not influence yield directly. This implies that time may be a limiting factor for conversion of applied phosphorus to different P fractions. Different soil P fractions may influence the yield indirectly through other soil factors as founded by use of appropriate statistical tools. Furthermore, only N was found to be playing a dominant role in predicting the yield of capsicum under protected cultivation. The time of application of N also plays a vital role for the increased production of capsicum. The application of N just before fruiting stage gave better result compared to other critical growth stages during the study period. The best treatment combinations for higher yield of capsicum were when medium to high dose of N (N-100, 120) and P (P-60, 80) and low to medium dose of K (K-40, 60) was applied. Further studies may be conducted at different physio-geographical locations to get a robust nutrient recommendation for capsicum under protected cultivation.ThesisItem Open Access PHOSPHATE ADSORPTION IN SOILS OF ASSAM IN RELATION TO PHYSICO-CHEMICAL PROPERTIES AND PLANT UPTAKE(AAU, Jorhat, 2019-07) RAJKHOWA, MONTRISHNA; Bhattacharyya, D.The study investigated the Phosphate (P) adsorption in four (4) major soil orders of Assam. It was conducted in sixteen (16) surface (0-30 cm) and sub-surface (30-60 cm) soil samples, collected from two locations each of the order Entisol, Inceptisol, Alfisol and Ultisol. There were wide variations in physico-chemical characteristics of the soils with pH, organic carbon, texture, clay content, CEC, AEC, per cent base saturation (PBS) and free oxides of Fe and Al which ranged from 4.86 to 5.60, 0.66 to 1.17 per cent, sandy loam to clay , 18 to 39.5 per cent , 6.72 to 19.73 cmol (P+) kg–1, 1.64 to 2.80 cmol (-) kg-1, 21.16 to 44.39 per cent, 1.08 to 3.21 per cent and 0.60 to 1.08 per cent, respectively. In the soils forms of phosphorus present in variable amounts but had the same sequence of abundance viz., Fe-P>Al-P>Organic P>Residual-P>Ca-P in all soils. Total acidity of the soils ranged from 1.60 to 3.36 cmol (p+) kg-1. Forms of acidity revealed that total potential acidity was the most dominant forms acidity followed by pH dependent acidity, exchangeable acidity and total acidity in soils of Assam. The adsorption of P in the soils was studied by conducting batch experiment in the laboratory by equilibrating two (2) g soil in duplicate with 20 ml 0.01 M CaCl2 solution containing 5, 10, 20, 40, 60, 80, 100 and 150 mg P L-1 as KH2PO4. The results of adsorption studies on P were discussed in terms of per cent adsorption of added P (%AdsP), Langmuir and Freundlich adsorption parameters. The per cent of adsorbed P (%AdsP) decreased with the increased of added P. The P adsorption data was found to be the best fit in Langmuir adsorption isotherm when resolved into two parts.The Langmuir parameters viz., the adsorption maxima (b) were higher for part II (upper part) whereas the bonding energy constant (k) was higher for part I (lower part) of the isotherms. The highest b2 of part II was found in Ultisol (5882.35 mg kg-1 in S8d1) and the lowest was found in Entisol (1037mg/kg in S1d2).The highest bonding energy constant (k) value for part I was observed in Ultisol (0.795 L mg-1) and the lowest in Entisol (0.055 L mg-1). Phosphate adsorption maxima (b1) of part I had a significant positive correlation with OC (r = 0.814**), clay content (r = 0.632**), Ex. Ca (r=0.701**), CEC (r = 0.874**) and free Fe2O3(r = 0.840**), toal P (r = 0.541*), Fe-P (r = 0.607*) and Al-P (r = 0.512*) content of the soils. The bonding energy constant (k1) of the part I and part II of the isotherm was found to have significant positive correlations with OC (r = 0.731** and 716** ), clay (r = 0.655** and 0.642**), CEC (r=0.890** and 0.640**) and Fe2O3 (r = 0.732** and 815**) of the soils, respectively. Freundlich adsorption parameter K had a significant positive correlation with OC (r = 0.801**), CEC(r=0.908**), clay content (r = 0.660**), Ex. Ca(r=0.537*), Free Fe2O3(r = 0.810**) and Al2O3 (r = 0.571*) of the soils. The Bray 1 P significantly negatively correlated with P adsorption maxima (b1) (r = - 0.599*), bonding energy constant (k1) (r = - 0.594*), MPBC (r = - 0.599*) and Freundlich’s n (r = - 0.744*) and K (r = - 0.616*). Bray2 P also significantly negatively correlated with P adsorption maxima(r= - 0.668**), MPBC (r = - 0.533*) and Freundlich’s n (r = - 0.736**) and K (r= -.571**). P uptake was highest in soil S5d1 (0.042 g plant-1) and lowest in soil S4d1 (0.027 and 0.026 g plant-1) with as well as without addition of P. The P uptake by the Maize had no significant correlation with P adsorption parameters. It might be due to greater role of the intensity factor viz. P concentration and diffusion in supply of P to plant root than the P adsorption parameters. Therefore, amount of P required to obtain 0.2 mg P L-1 in equilibrium soil solution was different in different soil orders. It was highest in Ultisol S8d1 (90.89 mg PL-1) and the lowest in Entisol S2d1 (32.78 mg PL-1). The values of P supply parameter (SP) ranged from 0.38 in soil S7d1 to 49.38 in soil S3d2. Thus the findings of present investigation on P adsorption capacity of soils of Assam will be useful in P fertilizer management and recommendation of P fertilizer for growing crops in these soils.ThesisItem Open Access TARGETED YIELD BASED FERTILIZER PRESCRIPTION MODEL FOR SCENTED RICE(AAU, Jorhat, 2019-07) DOLEY, MOMIN; Das, K. N.Field experiments were conducted at the Instructional-cum-Research (ICR) Farm, Assam Agricultural University, Jorhat during the year 2017-18 and 2018-19 to generate Targeted Yield based Fertilizer Prescription Model for Scented Rice. In order to develop fertilizer prescription equations, fertility gradient experiment was conducted taking kharif rice (cv. Ranjit) as exhaust crop by creating three fertility gradient strips. After harvest of gradient crop, test crop experiment was conducted in the same field with scented rice (cv. Keteki joha) by superimposing 24 treatment combinations consisting of five levels of N (0, 10, 20, 40 and 60 kg ha-1), four levels of P2O5 (0, 5, 10 and 20 kg ha-1), three levels of K2O (0, 10 and 20 kg ha-1) and three levels of vermicompost (0, 2 and 3 t ha-1) in each of these fertility gradient strips. Integrated nutrient management approach brought about a positive influence on organic carbon, soil available nutrient status, crop yield and uptake of nutrients by scented rice. Combined application of 60 kg N, 10 kg P2O5 and 10 kg K2O per hectare along with 3 tonnes of vermicompost per hectare resulted the highest available NPK in soil along with the highest crop yield and uptake of nitrogen, phosphorus and potassium by rice as compared to other treatments. Fertilizer prescription equations were formulated for scented rice by following Ramamoorthy’s Inductive- cum-targeted yield approach. Based on the experiments, the nutrient requirement (NR) for producing one quintal of scented rice was found to be 2.96, 0.21and 2.67 kg q-1 with respect to N, P and K, respectively. The soil efficiency for N, P and K was found to be 36.44%, 37.13%, 50.17% in 2017-18, respectively and 35.33%, 32.88%, 49.87% in 2018-19, respectively and 35.89, 35.01, 50.02 kg q-1 in pooled analysis, respectively. The N, P, K contributions to scented rice from fertilizers were 52.22%, 23.08%, 63.55%, respectively in 2017-18 and 54.43%, 23.04%, 64.13%, respectively in 2018-19 and 53.33, 23.06, 63.84 kg q-1, respectively in pooled analysis and found highest in K-fertilizer. Conversely, the per cent contribution of N, P and K from organic component that is organic efficiency was 9.69%, 1.08%, 21.6%, respectively in 2017-18 and 10.57%, 1.15%, 22.4%, respectively in 2018-19 and 10.13, 1.12, 22 kg q-1, respectively in pooled and found to be unassuming in all the nutrients. Based on nutrient requirement, contribution from soil, contribution from fertilizer and contribution from organic manure the fertilizer prescription equations were developed for scented rice (cv. Keteki joha) and an estimate of fertilizer doses were formulated in the form of ready reckoner for a range of soil test values and desired yield targets.ThesisItem Open Access CARBON AND NITROGEN MINERALIZATION IN AN INCEPTISOL WITH AND WITHOUT STUBBLE ADDITION(AAU, Jorhat, 2019-07) Nandy, Suravi; Borah, NilayA laboratory experiment was carried out to evaluate carbon and nitrogen mineralization in soil as influenced by rice stubble addition. Bulk surface (0-15 cm) soils (sandy clay loam with pH 4.6 and organic carbon 6.2 g/kg), collected from winter rice (variety - Ranjit) field after harvest of the crop, were processed and used to fill the PVC (polyvinyl chloride) pipes (diameter 9.0 cm) to a depth of 15 cm and incubated for 105 days imposing different treatments. Rice stubbles were treated in the field by spraying glyphosate (2.05 g a.i/l) and commercial yogurt (5 g/l) mixtures solution. Both treated and untreated stubbles were collected from the field, chopped into small pieces (1.5 to 2.0 cm long) and added to the columns with and without incorporation. A column was incubated without addition of the rice stubbles. The soil columns (over a layer of 10 cm sand) were kept in a tray filled with sand under constant saturation in a completely randomized design with four replications. The soil moisture content of the columns varied from 27.6 to 31.4 % (w/w) and the maximum temperature varied from 21.3 to 29.3 0C during the experiment. The CO2 evolution from the soils increased up to 6th week of incubation and maximum value (30.6 mg/kg soil) was observed with incorporation of treated rice stubble. The lowest value during this period was observed in soil without rice stubble and differed significantly to the treatments for each sampling stage. The CO2 evolution from the soils every third day after 6th week of incubation increased gradually reaching the peak at around 9th week after incubation in treatments receiving rice stubble. Thereafter, the CO2 evolution from the soils decreased gradually with a little rise at 12th week after incubation. Significant differences in CO2 evolution from the soils were not observed between incorporated and unincorporated treatments for both treated and untreated rice stubble, except a few occasions. The organic carbon content of the soils was not affected by the stubble management up to 42 days after incubation, which significantly increased due to incorporation of treated rice stubble up to 84 days, and due to addition of stubble at 84 and 105 days of incubation compared to soil without stubble. The labile organic carbon content of the soils significantly increased 42 days after incubation in soils with rice stubble, except untreated and unincorporated treatment compared to without stubble. However, the microbial biomass carbon was relatively non-significant, except at 63 days of incubation where incorporation of untreated and retention of treated stubbles showed higher significant contents over retaining untreated stubble or without stubble. The NO3-N significantly increased up to 84 days of incubation with stubbles, irrespective of incorporation and glyphosate-yogurt treatment compared to without stubble. The soil pH was affected only at 105 days after incubation, where it significantly decreased due to retention of treated stubble or incorporation of stubble compared to without stubble and retention of untreated stubble. However, the exchange acidity and total acidity in soils significantly increased after 63 days after incubation due to incorporation of treated or untreated stubble and retention of treated stubble. The cation exchange capacity, exchangeable cations, viz. NH4+, Ca2+, Mg2+ significantly increased with incorporation of rice stubble, while the effect for K+ was observed only with treated stubble incorporation. The available phosphorous (P) and potassium (K) significantly increased due to stubble incorporation, but available nitrogen was unaffected by the treatments.ThesisItem Open Access Mapping of Carbon Stock in different Agro-Ecosystems of Jorhat District using Remote-sensing(AAU, 2015) Baruah, Rashmi; Medhi, B.K.Soil organic carbon mapping at larger scale to assess the carbon stock using remote-sensing is useful in predicting the need based strategies to be adopted in the context with land use change and different land management scenarios. The present study aims to develop data base for mapping carbon stock in different agro-ecosystem (AESs) for forest and agricultural lands of Jorhat district and to study the effectiveness of contiguously spaced spectral bands vis-a-vis other multispectral remote-sensing in carbon stock assessment. This study revealed that forest ecosystem had higher potential to sequester carbon than agricultural land. Among different agro-ecosystems (AESs), Humid Alluvial Flood Free (HAFF) situation have the highest biomass C stock followed by High Land (HL), Humid Alluvial Flood Prone (HAFP) and lowest in Char Area (CA). Soils of Jorhat district have high amount of organic carbon, especially in forest area of HL and CA. Among physical properties, bulk density ranged from 1.0-1.48 g/cc in HAFF, 1.19-1.61 g/cc in HAFP, 1.08-1.43 g/cc in HL and 1.15 g/cc to 1.51 g/cc in CA with increasing trend down the profile. In all the profiles under study, limit of variability in BD was within 11% of observed value with respect to mean. Sand content was dominant in all AESs followed by clay and silts content, baring for HL and CA. The extent of variability in relation to mean was found to be highest in silt fraction followed by clay and sand in HAFF and HL situations, while, highest variability was observed in case of clay followed by silt and sand fractions in HAFP and CA. Among different chemical properties, soil pH ranged 4.19-6.39 in HAFF, 5.26-7.22 in HAFP, 5.06-6.14 in HL and 5.35-6.88 in CA. Soil organic carbon ranged 0.90-20.40 g/kg in HAFF, 1.50-14.70 g/kg in HAFP, 1.20-17.40 g/kg in HL and 0.30 g/kg to 16.50 g/kg in CA. Cation exchange capacity (CEC) ranged from 1.80-9.80 cmol (p+) kg-1 in HAFF, 0.13-10.20 cmol (p+) kg-1 in HAFP, 5.0-17.40 cmol (p+) kg-1 in HL and 0.60-13.0 cmol (p+) kg-1 in CA. The maximum variations with respect to mean was found in case of EC followed by CEC and then pH in all AESs but in CA, soils showed highest variations in case of organic carbon (OC) followed by TN. Profiles under forest land use system exhibited relatively higher SOCD than paddy irrespective of AESs with an exception in one location of HAFF where land use under paddy showed higher value than forest land use system. Highest SOCD was recorded in HL followed by HAFF, HAFP and lowest in CA. Soil carbon stock (SCS) was highest for HAFF (56.24Tg) followed by HAFP (35.61 Tg), HL (12.29Tg) and lowest was recorded in CA (4.36Tg). Variations in SOCD of 94.20 per cent were found to be predictable from OC, depths, TN and clay content in forest soils, whereas, 89.40 per cent variations in SOCD were predicated from OC, depth and BD in case of paddy soil. Soil OC had signifiCAnt negative correlations with pH (r= -0.496**) and BD(r= -0.594**) while, it was correlated positively with Clay (r=0.447**), CEC(r=0.454**) and TN (r=0.496**). Similarly, SOCD showed negative and significant correlation with pH (r= -0.395**) and BD(r= -0.353**) and positive significant correlation with clay (r=0.443**), CEC (r=0.291**) and TN (r= 0.256*). Maximum efficiency to remove tones equivalent of CO2 from atmosphere as stable carbon was worked out to be highest in HAFF (2145.70 Tg) followed by HL (899.59 Tg), HAFP (616.85 Tg) and Char (16.0 Tg) which indicate potential efficiency of these zone in carbon sequestration and therefore, it is important in strategizing zones to plan for increasing efficiency accordingly in putting much thrust to conserve such situation in climate resilient perspective point of view. Moreover, spatial map prepared by kriging was found to be accurate with minimum error. Semivariogram generated by kriging showed higher autocorrelation of samples with minimum sampling error (Nugget value <1.0). Soil carbon stock could easily be calculated using krig map and could be recommended for precise data estimation. Considering total geographical area of Jorhat district (2852 sq.km), total potential for CO2 removal from atmosphere was worked to be 30.41 Tg as stable carbon over the Agro-Ecosystem.