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Dibrugarh, India

Bhattacharyya P.,Indian Statistical Institute | Karak T.,Upper Assam Advisory Center | Chakrabarti K.,University of Calcutta | Chakraborty A.,Bidhan Chandra Krishi Viswavidyalaya | And 2 more authors.
Environmental Earth Sciences | Year: 2014

The nature of selected soil-chemical and microbial properties influenced by tsunami affected and non-affected areas along the border areas of the alluvial Andaman Island in India were investigated. Soils of these areas have turned saline and saline-sodic due to the ingression of sea water. The electrical conductivity of the saturation extract of the surface soil varied from 11.2 to 23.8 dS m-1 in 2005, and it was decreased to 0.8-10.3 dS m-1 in 2006 due to the heavy rain in the following year after the tsunami. Soil quality indicators, like microbial biomass C, microbial metabolic quotient, microbial respiration quotient and fluorescein diacetate hydrolyzing activity, decreased in the tsunami affected soil in 2005, but slightly increased in 2006. All microbial parameters were significantly negatively correlated with the electrical conductivity, sodium absorption ratio and exchangeable sodium percentage. Suppression of microbial biomass and their activities in the soils due to the increased-salinity is of great agronomic significance and needs suitable intervention for sustainable crop production. Significant differences were found in soil-chemical and microbial characteristics between tsunami affected and non-affected areas. Hierarchical clustering algorithm on the basis of different soil-chemical and microbial characteristics revealed that there is significant difference in grouping between tsunami affected and non-affected zones. From this study, it can be concluded that the sea water ingression detrimentally influenced the microbial properties of tsunami affected soil. © 2014 Springer-Verlag Berlin Heidelberg. Source


Karak T.,Tocklai Experimental Station | Karak T.,Upper Assam Advisory Center | Bhattacharyya P.,Indian Statistical Institute | Paul R.K.,Indian Agricultural Research Institute
Clean - Soil, Air, Water | Year: 2014

The dynamic parameters of the transformation of fresh cow dung (FCD), municipal solid waste (MSW), pond sediment (PST), tea pruning litter (TPL), tea waste (TWE), and water hyacinth (WHH) into a manure using a co-composting process were investigated. Among the six different modes of compost, it was observed that the best quality of compost can be produced where the substrate was FCD/MSW/TPL/PST/TWE/WHH 1:1.5:1.5:2.5:2.5:1 with respect to Indian compost standard. Hierarchical agglomerative cluster analysis (HCA) for physical and chemical variables during composting yielded a dendrogram and formed two clusters, one of which includes temperature, amount of cadmium, chromium, copper, lead, MSW, nickel, phosphorus, and zinc and the other includes cation exchange capacity, FCD, germination index of chickpea, germination index of green gram, mercury, nitrogen, organic carbon (OC), pH, TPL, potassium, PST, TWE, and WHH. Principal component analysis (PCA) was applied to all the data sets, which resulted in nine, four, four, three, and two latent factors of the total variance in compost quality. Varifactors of PCA implied that the parameters responsible for metals and P were MSW and temperature variation, N was mainly related to PST and TWE whereas OC was influenced by TPL and FCD. Therefore, on application of HCA and PCA, a meaningful classification of the above-mentioned parameters has been obtained. Thus, these results should be effective measures for future in using tea garden waste materials for the preparation of valued eco-friendly compost. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Karak T.,Upper Assam Advisory Center | Sonar I.,Upper Assam Advisory Center | Paul R.K.,Indian Agricultural Research Institute | Das S.,Dibrugarh Polytechnic | And 2 more authors.
Bioresource Technology | Year: 2014

The present study reports the suitability of termite mounds as a bulking agent for composting with crop residues and cow dung in pit method. Use of 50kg termite mound with the crop residues (stover of ground nut: 361.65kg; soybean: 354.59kg; potato: 357.67kg and mustard: 373.19kg) and cow dung (84.90kg) formed a good quality compost within 70days of composting having nitrogen, phosphorus and potassium as 20.19, 3.78 and 32.77gkg-1 respectively with a bulk density of 0.85gcm-3. Other physico-chemical and germination parameters of the compost were within Indian standard, which had been confirmed by the application of multivariate analysis of variance and multivariate contrast analysis. Principal component analysis was applied in order to gain insight into the characteristic variables. Four composting treatments formed two different groups when hierarchical cluster analysis was applied. © 2014 Elsevier Ltd. Source


Karak T.,Upper Assam Advisory Center | Paul R.K.,Indian Agricultural Research Institute | Boruah R.K.,Upper Assam Advisory Center | Sonar I.,Upper Assam Advisory Center
The Scientific World Journal | Year: 2014

A sorption study was conducted on different soils collected from five agroecological zones of West Bengal, India, to understand the soil environmental behavior and fate of cadmium. For this purpose batch adsorption experiments were carried out at the native soil pH and at three different temperatures (25°C, 35°C, and 45°C). The adsorption data fitted by a linear least squares technique to the different sorption isotherms. Most data obtained give the good fit to both Freundlich and modified Langmuir isotherms, but they are not consistent with the linear Langmuir adsorption model. Thermodynamic parameters, namely, thermodynamics equilibrium constant at a particular temperature T (K T 0), Gibbs free energy at a particular temperature T (Δ G T 0), and change of enthalpy (Δ H 0) and change of entropy at temperature T (Δ S T 0), were also determined by applying sorption value and concentrations of Cd in equilibrium solution within the temperature range. The thermodynamic parameters revealed that Cd sorption increases as the values of K T 0, Δ G T 0, Δ H 0, and Δ S T 0 were increased on reaction temperatures. The spontaneous sorption reaction can be concluded due to high values of Δ G T 0. The positive values of Δ H 0 indicated that the Cd sorption is an endothermic one. Under these present conditions, the soil and its components possibly supply a number of sites having different adsorption energies for cadmium sorption. © 2014 Tanmoy Karak et al. Source


Karak T.,Upper Assam Advisory Center | Sonar I.,Upper Assam Advisory Center | Nath J.R.,Upper Assam Advisory Center | Paul R.K.,Indian Agricultural Research Institute | And 3 more authors.
Bioresource Technology | Year: 2015

Although, compost is the store house of different plant nutrients, there is a concern for low amount of major nutrients especially nitrogen content in prepared compost. The present study deals with preparation of compost by using agricultural wastes with struvite (MgNH4PO4·6H2O) along with termite mound. Among four composting mixtures, 50kg termite mound and 2.5kg struvite with crop residues (stover of ground nut: 361.65kg; soybean: 354.59kg; potato: 357.67kg and mustard: 373.19kg) and cow dung (84.90kg) formed a good quality compost within 70days of composting having nitrogen, phosphorus and potassium as 21.59, 3.98 and 34.6gkg-1, respectively. Multivariate analysis of variance revealed significant differences among the composts. The four composts formed two (pit 1, pit 2 and pit 3, pit 4) different groups. Two principal components expressed more than 97% of the total variability. Hierarchical cluster analysis resulted two homogeneous groups of composts. © 2015 Elsevier Ltd. Source

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