Methane emissions from rice fields amended with biogas slurry and farm yard manure     

Goutam Debnath  M. C. Jain  Sushil Kumar  K. Sarkar  Suresh K. Sinha 《Climatic change》1996,33(1):97-109

In an experiment on methane-emission measurements from rice fields amended with urea, biogas spent slurry (BSS) + urea, and farm yard manure (FYM) + urea, three distinctive peaks in the methane emissions were observed at 15, 46, and 69 days after transplanting (DAT) due to the availability of readily degradable C-sources. In all cases, the highest peak was at 69 DAT. The steepest Eh drop to a minimum of -320 mV was reached within two weeks of submergence. pH ranged between 7.5 and 8.5. The combined fertilization (FYM + urea) plot showed the maximum emission rate of 4.86 mg m^–2 h^–1 with a total load of 49.44 kg ha^–1 and was 2.3 times higher than (BSS + urea)-treated plot (22.08 kg ha^–1). Grain yields in urea, (BSS + urea) and (FYM + urea) plots were 3.34, 2.94, and 2.85 t ha^–1 respectively, suggesting that biogas slurry is a preferred source over FYM causing lesser environmental pollution without any significant reduction in grain yield.  相似文献   

Delineation of Active Faults, Nucleation Process and Pore Pressure Measurements at Koyna (India)   总被引：1，自引：0，他引：1  

R. K Chadha  H. K Gupta  H. J Kumpel  P. Mandal  A. Nageswara Rao  N. Kumar  I. Radhakrishna  B. K Rastogi  I. P Raju  C. S. P Sarma  C. Satyamurthy  H. V. S Satyanarayana 《Pure and Applied Geophysics》1997,150(3-4):551-562

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Factorial ecology of Calcutta (1981) revisited     

Prof.  Dr. Ashok K. Dutt  Gerardine D'Sa  Prof.  Dr. Charles B. Monroe 《GeoJournal》1989,18(2):151-162

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Selection of optimum frequency of a wind scatterometer     

Abhijit Sarkar  Raj Kumar  Mannil Mohan 《Journal of Earth System Science》1988,97(2):192-192

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Late Cretaceous mafic dykes in the Dharwar craton     

Anil Kumar  Y J Bhaskar Rao  V M Padma Kumari  A M Dayal  K Gopalan 《Journal of Earth System Science》1988,97(1):107-114

Palaeomagnetic, geochemical and geochronological studies have been conducted on a set of dolerite dykes intruding the Peninsular gneisses near Huliyurdurga town, Karnataka, as a reconnaissance survey indicated a Cretaceous age for them. The dykes are mainly tholeiitic in composition with their 87Sr/86Sr ratios tightly clustered around 0·7045. Their palaeomagnetic data (D _m =329°,I _m =−55°) and the corresponding palaeopole coordinates (λ _p = 34°S,L _p =108°E) are strikingly close to those of the Deccan Traps to the north. Whole rock K-Ar ages of these dykes ranging between 69 and 84 Ma are also similar to the range of K-Ar ages of the Deccan basalts. The chemical, palaeomagnetic and temporal coherence between the dykes and the Deccan basalts indicate that they may indeed be tectonically related events.  相似文献   

Pressure on lining due to initial stress field by finite-infinite-interface element method     

Prabhat Kumar  Bhawani Singh 《Rock Mechanics and Rock Engineering》1988,21(3):219-228

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Hydroclimatic fluctuations of the Upper Narmada catchment and its association with break-monsoon days over India     

Nityanand Singh  M K Soman  K Krishna Kumar 《Journal of Earth System Science》1988,97(1):87-105

In this paper, hydroclimatic fluctuations of the Upper Narmada catchment (upto Narmadasagar damsite) have been studied by examining the time series (1901–80) of (i) 1-to 10-day annual extreme rainfall; (ii) seasonal total rainfall between May and October; (iii) the precipitation concentration index (PCI); (iv) a modified version of PCI(MPCI); and (v) parameters of the periods contributing specified percentages of rainfall to annual total. Most of these parameters followed the normal distribution and did not show any significant long-term trend. However, some dominant long period oscillations have been noticed in extreme rainfall, seasonal rainfall, PCI and MPCI series. Influence of break-monsoon days over India during July and August on the rainfall activities of the Upper Narmada catchment has also been investigated and salient findings discussed.  相似文献   

Radioelement geochemistry of alkali granites of the Kerala region,south-west India     

M Santosh  K Vijaya Kumar 《Journal of Earth System Science》1986,95(1):103-115

Th, U and K abundances in four alkali granites of the Kerala region, south-west India, are presented. The plutons show high radioelement levels, correlatable with those of alkali granites in other regions. The nature of variation is consistent with the correlation of Th and U with accessory phases like sphene, zircon, allanite, apatite and monazite. A geochronologic correlation is also observed between the alkali granites and the Th-bearing beach placers of the region. The petrogenetic features of the alkali plutons, their taphrogenic association, Pan-African affiliation and high Th/U levels suggest that the alkali plutons are favourable locales for radioelement exploration.  相似文献   

International Symposium on Marine Positioning     

Muneendra Kumar  George A. Maul 《Journal of Geodesy》1987,61(3):293-295

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Genesis of certain bauxite profiles from India     

K.S. Balasubramaniam  M. Surendra  T.V.Ravi Kumar 《Chemical Geology》1987,60(1-4):227-235

An attempt is made to reveal a geochemical compatibility with paleoenvironment to understand the genesis of bauxite deposits that are derived from two different parent rocks. For this purpose two in situ bauxite profiles, one developed over basalt and another over sandstone, have been taken. Gibbsite is the major mineral in all these bauxites with minor occurrences of goethite, hematite, anatase, kaolinite, etc. From the study it is evident that the paleoenvironment and geochemical processes are vital factors that could lead to the formation of bauxites. The significance of this is fully discussed.  相似文献