Impact of Subsurface Drainage on Improvement of Crop Production and Farm Income in North-West India     

K.K. Datta  Laxmi Tewari  P.K. Joshi 《Irrigation and Drainage Systems》2004,18(1):43-56

The Indian Council of Agricultural research has given priority to control and manage salinity problems that have developed in north-west India. Multi-disciplinary taskforces have recommended installation of subsurface drainage for salinity control, based on design and management techniques developed by the Central Soil Salinity Research Institute (CSSRI), to rehabilitate lands with excess soil salinity. After small-scale studies, large-scale pilot projects were launched to install subsurface drainage in problem areas. One such attempt in was initiated in the north-west region of India where a large-scale drainage project was carried out with Dutch collaboration. We assessed the impact of investments in subsurface drainage in order to validate past funding on research of drainage in India. The important methods used for assessing the efficiency benefits of drainage investment were: to determine the impact of subsurface drainage in terms of net present value, internal rate of returns, consumers' surplus and producers' surplus; to assess the social welfare in terms of social equality and sustainability of the drainage system; and to examine the factors affecting the sustainability of the technology. The internal rate of return was computed to assess the efficiency parameter of subsurface drainage for salinity management. In order to measure the changes in inequality distribution of income, Gini concentration ratios were computed with and without installing sub surface drainage. The Radar Approach, a method based on a graphical display of differences between actual ideal performance, was used to quantify drainage sustainability in terms of optimizing gains and conserving, or improving the quality of soil and water resources. There were several farm-level benefits as a result of installing subsurface drainage: these included: (i) a substantial increase in farm income; (ii) cropping intensification and diversification toward high value crops; and (iii) generation employment. A high internal rate of return justified investment in subsurface drainage. Income inequalities across farms were reduced. The radar approach showed improvement in sustainability in terms of economic gains and resource conservation. Despite of these economic, social, and environmental benefits, the sustainability of subsurface drainage technology is questionable. The specific reasons include: (i) the nature of the technology; (ii) lukewarm collective action by the beneficiaries; (iii) conflicting objectives among beneficiaries; and (iv) growing numbers of free riders. To a large extent these were addressed in the study area by forming village committees. Without appropriate institutional arrangements, subsurface drainage may not yield the desired results, and in the long run may result in neglect of operation and maintenance needs and ultimately the abandonment of the technology.  相似文献   

Effect of electrolyte solution on saturated hydraulic conductivity of soils varying in clay type and content,and iron oxides     

A. Das  B. Datta 《植物养料与土壤学杂志》1987,150(3):187-192

Changes of hydraulic conductivity (HC) at electrolyte solutions having different combinations of sodium adsorption ratio (SAR)¹ and electrolyte concentration (EC), were monitored in soil columns packed with samples from Rhodustalf, Chromustert, Andic Eutropept and Oxic Rhodustult, four subtropical soils varying in clay type and content, and iron oxides. In general, it was observed that the HC dropped with the decrease of EC and with the increase in SAR of solutions, or, with the increase in exchangeable sodium percentage (ESP) of the soil. In montmorillonitic soils the reduction of HC had been most pronounced, while the kaolinite-rich soils showed only an insignificant drop in HC even at the highest SAR coupled with the lowest EC. The improvement or revival of HC from its final drop was examined upon leaching the soil columns finally with the initial high concentration solution. Montmorillonitic soils showed moderate to high revival of HC, while for montmorillonite-illite-kaolinite mixed clayey soils and kaolinitic soils the improvement of HC was low and practically nil respectively. The percentage revival of HC from its final drop was employed as a criterion to assess the major cause of HC reduction and it was found that irrespective of clay mineralogy “dispersion and subsequent pore plugging” played a major role in reducing the HC of soils, though in montmorillonitic soils swelling had been found to be an almost equivalent additional cause of HC drop. Simple correlations (r) between the saturated HC at varying SAR & EC and different physico-chemical and mineralogical properties have been calculated and its role and implications have been discussed.  相似文献   

Predicting Metal Uptake and Risk to the Human Food Chain from Leaf Vegetables Grown on Soils Amended by Long-Term Application of Sewage Sludge     

S. P. Datta  S. D. Young 《Water, air, and soil pollution》2005,163(1-4):119-136

The success of risk assessment of metal contaminated soils depends on how precisely one can predict the bio-availability of metals in soil and transfer to the human food chain. In the present investigation, we tested several formulations of the ‘free-ion activity model (FIAM)’ to predict uptake of Cd, Zn and Cu by perpetual spinach (Beta vulgaris, Cicla) grown on a range of soils amended with sewage sludge. The model was parameterised using data measured on samples of pore water extracted by centrifugation and with porous Rhizon samplers installed within the rhizosphere of the growing plants. Free ion activities (M²⁺) were estimated following speciation of solution data using version 6 of the ‘Windermere Humic Aqueous Model (WHAM-VI). For all three metals, the best formulation of the FIAM appeared to require only one hypothetical root sorption site without competition from protons. Values of (M²⁺) could also be predicted satisfactorily from a pH-dependent Freundlich relation. Thus, from a combined FIAM–Freundlich relation and population dietary information, it was possible to estimate risk (hazard quotients) to consumers from very simple soil measurements: extractable metal content (0.05 M EDTA (Zn and Cu) or 1 M CaCl₂ (Cd)), soil humus content and pH. The role of increased soil organic matter content and soil pH, in reducing risk to consumers, is illustrated for Cd in a hypothetical soil at the current UK statutory Cd limit for sludge application to agricultural land.  相似文献   

Carbon Stock, Afforestation and Acidic Deposition: An Analysis of Inter-Relation with Reference to Arid Areas     

Sanjay Kumar  R. Datta  S. Sinha  T. Kojima  S. Katoh  M. Mohan 《Water, air, and soil pollution》2001,130(1-4):1127-1132

Recent advances in desert afforestation underlines its viability and importance in combating global warming and acidification. In this paper, the inter-relation between afforestation, global warming and acid rain has been analyzed. Numerical simulations indicate that afforestation of deserts has distinct advantage as carbon sink and as an important factor for changing microclimate of the region rather than a source of energy. Acidic deposition may well be utilised as fertiliser in nutrient deficit soil of tropical arid areas. However, past trends and projections of acidic deposition in arid areas adjacent to Thar deserts indicate an early efforts are required to cap the opportunity. Delays may contribute towards more incidences of failures.  相似文献   

Genotype and hormonal effects on callus formation and regeneration in mulberry     

B. N. Susheelamma  K. Raja Shekar  A. Sarkar  M. R. Rao  R. K. Datta 《Euphytica》1996,90(1):25-29

Summary Twenty-five mulberry genotypes were studied for callus induction, to evaluate the effectiveness of hormones in promoting callus growth and to identify genotypes capable of regenerating plants. Fifteen genotypes showed callus initiation. Genotypic variation was also noted for longevity and rate of growth of callus cultures. Calli of different genotypes were maintained for more than one year. Frequency of callus initiation was high on Murashige & Skoog's modified medium incorporated with 2.0 mg/l 2,4-D, 100 mg/l casein acid hydrolysate and 150 ml/l coconut water. Regeneration through organogenesis was achieved in six genotypes indicating genotypic specificity.  相似文献   

Spermatozoa produced during winter are superior in terms of phenotypic characteristics and oviduct explants binding ability in the water buffalo (Bubalus bubalis)     

Haneef Ahmad Rather  Arumugam Kumaresan  Pradeep Nag  Vimlesh Kumar  Samiksha Nayak  Vipul Batra  Bilal Ahmad Ganaie  Rubina K. Baithalu  Tushar Kumar Mohanty  Tirtha Kumar Datta 《Reproduction in domestic animals》2020,55(11):1629-1637

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Gamma ray-induced genetic manipulations in flower colour and shape in Dendranthema grandiflorum and their management through tissue culture     

S. K. Datta    D. Chakrabarty  A. K. A. Mandal 《Plant Breeding》2001,120(1):91-92

Rooted cuttings of Dendranthema grandiflorum cv. ‘Puja’ were treated with different doses of gamma rays. Sectorial somatic mutations both in flower colour and shape were detected in all the doses. The original floret colour of ‘Puja’ is red‐purple and florets are flat spoon shaped. One of the mutant floret colour was yellow‐orange with original flat florets and another mutant floret colour was yellow‐orange with tubular florets. Original and mutated ray florets were cultured on agar‐solidified Murashige and Skoog basal medium supplemented with sucrose and different combinations of 1‐naphthaleneacetic acid (NAA) and 6‐benzylaminopurine (BAP). Direct shoot organogenesis was seen within 2 weeks of culture initiation. The best regeneration was obtained on medium supplemented with 1 mg/l BAP + 0.5 mg/l NAA. Shoots regenerated from all explant types were rooted in vitro and transferred to the field. Regenerated plants flowered true‐to‐explant floret colour and shape. The isolated yellow floret colour mutants and yellow floret colour mutants with tubular florets were maintained vegetatively and have proved to be true to type in two successive generations.  相似文献   

Characterization of serum-free buffalo granulosa cell culture and analysis of genes involved in terminal differentiation from FSH- to LH-responsive phenotype     

Monga R  Sharma I  Datta TK  Singh D 《Domestic animal endocrinology》2011,41(4):195-206

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Sequential morphological changes in chicken erythrocytes after in vivo and in vitro exposure to phenylhydrazine-hydrochloride     

K Datta  J L Soni  I C Datta 《Research in veterinary science》1990,48(1):12-17

In acute haemolytic anaemia of chickens, induced with the oxidant chemical phenylhydrazine-hydrochloride, maximum degenerative changes in the in vivo exposed erythrocytes occurred on day 3 after injection. Microspherocytic transformation, dumb-bell shaped red blood cells and foamy squashed nuclei predominated. Heinz body formation was the cytoplasmic hallmark of the haemolytic anaemia. Marked reticulocytosis on day 5 indicated spontaneous regeneration. In vitro exposure to the chemical agent evoked similar morphological aberrations/Heinz bodies, microspherocytic transformation and nuclear degeneration. These were induced much earlier, presumably because of the absence of a protective internal milieu. Nevertheless, a basic similarity in morphology was evident. The in vitro test system might be suitable for screening oxidant chemicals and drugs.  相似文献   

Pathomorphological changes in calf erythrocytes during phenylhydrazine-induced acute hemolytic anaemia.     

M L Sharma  J L Soni  K Datta 《Archiv fuer experimentelle veterinaermedizin》1991,45(1):45-48

In acute hemolytic anaemia of calves induced with phenylhydrazine-hydrochloride, accentuated degenerative changes in circulating erythrocytes occurred on the 5th d post-injection. Marked anisocytosis and poikilocytosis were observed. Crenated cells, acanthocytes (star-shaped cells), dacrocytes (tear drop cells), bite cells, and schistocytes predominated. Heinz bodies were the cytoplasmic hallmark of hemolytic anaemia. The regenerative nature of anaemia was evidenced by early appearance of reticulocytes in peripheral blood.  相似文献