Potassium and Residue Management Options to Enhance Productivity and Soil Quality in Zero Till Maize–Wheat Rotation     

Raghavendra Madar  Yudh Vir Singh  Mahesh Chand Meena  Tapas Kumar Das  Sunita Gaind  Rakesh Kumar Verma 《洁净——土壤、空气、水》2020,48(3)

Crop residue burning and imbalanced use of chemical fertilizers in intensive cereal–cereal rotations are present ecological threats in any agro‐ecosystem of the world. Therefore, identification of best suitable agricultural practices can be a feasible option. The present experiment was initiated in 2013 and consisted of four residue levels (0, 2, 4, and 6 Mg ha^?1) and five potassium (K) levels (0, 50, 100, 150% recommended dose of K and 50%RDK+K solubilizing bacteria, KSB). Crop residue (CR) and K management significantly improve crop and soil quality associated parameters. Among the treatments, maximum increase in crop growth, physiological parameters, grain yield, quality aspects, and water productivity are recorded with the application of 4–6 Mg ha^?1 CR. Application of 50%RDK+KSB also significantly increases crop and soil related parameters. Soil quality indicators (bulk density, pH, electrical conductivity, and available micronutrients) do not vary significantly with CR and K management. Change in soil organic carbon status, soil enzymes, and potassium‐solubilizing bacterial count are significantly increased with 4–6 Mg ha^?1 CR and application of 50%RDK+KSB, and this is in accordance with correlation study carried out. Therefore, it is concluded that CR retention (4–6 Mg ha^?1) and reduction of inorganic K fertilizer by 50% and inoculation of KSB enhance the soil quality indicators and thereby improve crop growth, physiological parameters, grain yield, and quality aspects along with water productivity under zero till maize–wheat rotation.  相似文献   

Application of tank,NAM, ARMA and neural network models to flood forecasting     

Tawatchai Tingsanchali  Mahesh Raj Gautam 《水文研究》2000,14(14):2473-2487

Two lumped conceptual hydrological models, namely tank and NAM and a neural network model are applied to flood forecasting in two river basins in Thailand, the Wichianburi on the Pasak River and the Tha Wang Pha on the Nan River using the flood forecasting procedure developed in this study. The tank and NAM models were calibrated and verified and found to give similar results. The results were found to improve significantly by coupling stochastic and deterministic models (tank and NAM) for updating forecast output. The neural network (NN) model was compared with the tank and NAM models. The NN model does not require knowledge of catchment characteristics and internal hydrological processes. The training process or calibration is relatively simple and less time consuming compared with the extensive calibration effort required by the tank and NAM models. The NN model gives good forecasts based on available rainfall, evaporation and runoff data. The black‐box nature of the NN model and the need for selecting parameters based on trial and error or rule‐of‐thumb, however, characterizes its inherent weakness. The performance of the three models was evaluated statistically. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

A hybrid deterministic and stochastic approach for tsunami hazard assessment in Iquique,Chile     

González  Juan  González  Gabriel  Aránguiz  Rafael  Melgar  Diego  Zamora  Natalia  Shrivastava  Mahesh N.  Das  Ranjit  Catalán  Patricio A.  Cienfuegos  Rodrigo 《Natural Hazards》2020,101(1):231-253

Natural Hazards - This paper presents an investigation of the collapse of a 325-year-old multi-tiered heritage temple during the 2015 Gorkha earthquake in Kathmandu, Nepal. The research comprises a...  相似文献   

In-orbit Performance of UVIT and First Results     

S. N. Tandon  J. B. Hutchings  S. K. Ghosh  A. Subramaniam  G. Koshy  V. Girish  P. U. Kamath  S. Kathiravan  A. Kumar  J. P. Lancelot  P. K. Mahesh  R. Mohan  J. Murthy  S. Nagabhushana  A. K. Pati  J. Postma  N. Kameswara Rao  K. Sankarasubramanian  P. Sreekumar  S. Sriram  C. S. Stalin  F. Sutaria  Y. H. Sreedhar  I. V. Barve  C. Mondal  S. Sahu 《Journal of Astrophysics and Astronomy》2017,38(2):28

The performance of the ultraviolet telescope (UVIT) on-board AstroSat is reported. The performance in orbit is also compared with estimates made from the calibrations done on the ground. The sensitivity is found to be within \(\sim \)15% of the estimates, and the spatial resolution in the NUV is found to exceed significantly the design value of \(1.8^{\prime \prime }\) and it is marginally better in the FUV. Images obtained from UVIT are presented to illustrate the details revealed by the high spatial resolution. The potential of multi-band observations in the ultraviolet with high spatial resolution is illustrated by some results.  相似文献   

Mg VIII DIAGNOSTIC LINE RATIOS IN SKYLAB SOLAR OBSERVATIONS     

Foster  V. J.  Keenan  F. P.  Reid  R. H. G.  Doyle  J. G.  Zhang  H. L.  Pradhan  A. K.  Widing  K. G. 《Solar physics》1997,170(2):217-225

Recent calculations of Mgviii electron and proton impact excitations rates are used to derive theoretical electron temperature (T _e)- and density (N _e)-sensitive emission line ratios involving transitions in the 315–782 Å wavelength range. Some of these ratios are presented in the form of ratio–ratio diagrams, which should in principle allow both N _e and T _e to be deduced. These results are compared with solar observational data from Skylab, but agreement between theory and observation is very poor, probably due to blending.  相似文献   

Robertson-Walker viscous fluid model     

G. Mohanty  B. D. Pradhan 《Astrophysics and Space Science》1991,181(1):1-5

Robertson-Walker cosmological model with bulk viscosity is investigated with equation of statep=(–1). The cosmological solution of the model is obtained with the help of the special law of variation for Hubble's deceleration parameter. Some physical consequences of the solution is studied pertaining to two extreme cases of the equation of state.  相似文献   

Multi-stage metasomatism of diamondiferous eclogite xenoliths from the Udachnaya kimberlite pipe,Yakutia, Siberia   总被引：1，自引：1，他引：0  

Kula?C.?MisraEmail author  Mahesh?Anand  Lawrence?A.?Taylor  Nikolai?V.?Sobolev 《Contributions to Mineralogy and Petrology》2004,146(6):696-714

The primary garnet (pyrope-almandine)-omphacite (Cpx 1, 6.5–7 wt% Na₂O)-sulfide (Fe-Ni-Co mss) assemblage of the two diamondiferous eclogite xenoliths studied (U33/1 and UX/1) experienced two mantle metasomatic events. The metasomatic event I is recorded by the formation of platy phlogopite (~ 10 wt% K₂O), prior to incorporation of the xenoliths in the kimberlite. The bulk of the metasomatic alteration, consisting of spongy-textured clinopyroxene (Cpx 2A, 1–3 wt% Na₂O), coarser-grained clinopyroxene (Cpx 2B, 2–5 wt% Na₂O), pargasitic amphibole (~ 0.8 wt% K₂O; 3–3.5 wt% Na₂O), kelyphite (Cpx 3, mostly <1 wt% Na₂O; and zoned Mg-Fe-Al spinel), sodalite, calcite, K-feldspar, djerfisherite (K_5.95Na_0.02Fe_18.72Ni_2.36Co_0.01Cu_4.08S₂₆Cl ) and a small amount of K-Ca-Fe-Mg glass, is ascribed to the metasomatic event II that occurred also in the upper mantle, but after the xenoliths were incorporated in the kimberlite. A pervasive chloritic alteration (mainly clinochlore + magnetite) that overprints earlier assemblages probably took place in the upper crustal environment. The diamonds are invariably associated with secondary clinopyroxene and chlorite, but the diamonds formed before the entrainment of the xenoliths in the Udachnaya kimberlite.Editorial Responsibility: T.L. Grove  相似文献   

Response of Sandy Lake in Schirmacher Oasis,East Antarctica to the glacial-interglacial climate shift     

Badanal Siddaiah Mahesh  Anish Kumar Warrier  Rahul Mohan  Manish Tiwari  Rajdeep Roy  Rajesh Asthana  Rasik Ravindra 《Journal of Paleolimnology》2017,58(3):275-289

Freshwater lakes in Antarctica fluctuate from ice-free state (during austral summer) to ice-cover state (during austral winter). Hence the lakes respond instantly to the seasonal climate of the region. The Antarctic seasons respond sharply to the glacial and interglacial climates and these signatures are archived in the lake sediments. A sediment core from Sandy Lake, a periglacial lake located in Schirmacher Oasis of East Antarctica records distinct changes in grain-size, C, N, C/N ratios (atomic), δ¹³C_OM and δ¹⁵N_OM contents during the last 36 ky. The contents of the sedimentary organic matter (OM) proxies (C_org ~ 0.3 ± 0.2%, C/N ratios ~9 ± 5 and δ¹³C_OM ~?18 ± 6‰) indicate that the OM in this lake sediment is a product of mixing of terrestrial and lacustrine biomass. Distinctly lower contents of C_org (~0.2%) and sand (~50%), low C/N ratios (~8) and depleted δ¹³C_OM (~?20‰) during the Last Glacial Maximum (LGM: 32–17 ky BP based on Vostok Temperatures) suggest greater internal (autochthonous) provenance of organic matter and limited terrestrial (allochthonous) inputs probably due to long and intense winters in the Antarctic. Such intense winters might have resulted the lake surface to be ice-covered for most part of the year when the temperatures remained consistently colder than the Holocene temperatures. The denitrification within the lake evident by enriched δ¹⁵N_OM (>10‰) during Antarctic LGM might have resulted from oxygen-limitation within the lake environment caused by insulated lake surface. The gradual increases in δ¹³C_OM, C/N and sand content starting at ~11 ky BP and attaining high values (~?11‰, ~10 and ~80% respectively) at ~6 ky BP together suggest a subtle change in the balance of sources of organic matter between algal and macrophyte/bryophyte nearly 8–9 ky later to the beginning of the deglaciation. Thus the seasonal opening-up of the Sandy Lake similar to the modern pattern started with the establishment of the optimum temperature conditions (i.e., 0 °C anomaly) in the Antarctic, prior to which the lake environment might have remained mostly insulated or closed.  相似文献   

Spatio-Temporal Assessment of Groundwater Potential Zone in the Drought-Prone Area of Bangladesh Using GIS-Based Bivariate Models     

Ahmed  Naser  Hoque  Muhammad Al-Amin  Pradhan  Biswajeet  Arabameri  Alireza 《Natural Resources Research》2021,30(5):3315-3337

Natural Resources Research - Groundwater is one of the most dynamic and renewable natural resources found in the earth’s crust. A spatio-temporal assessment of groundwater potential zone...  相似文献   

Consolidation and Drainage Characteristics of Expansive Soil Stabilized with Fly Ash and Dolochar     

S. K. Mohanty  P. K. Pradhan  C. R. Mohanty 《Geotechnical and Geological Engineering》2016,34(5):1435-1451

Expansive soils undergo alternate swelling and shrinkage due to cyclic wetting and drying when left to nature. This property of Expansive soil affects its strength and stiffness characteristics thereby causing damage and distress to structures built on them. Industrial wastes can be added scientifically to these soils in modifying and reducing their swelling and shrinkage behaviour and increasing their strength and stiffness. In this technical article, an attempt has been made to study the compressibility and drainage characteristics of these soils using economic and ecofriendly industrial wastes such as Fly Ash and Dolochar as stabilizers. This paper also focuses on many other improved engineering properties of base soil like liquid limit, plasticity index, differential free swell, compaction and consolidation characteristics of Expansive (BC) soil stabilized with Fly Ash and Dolochar in different proportions. The virgin Expansive soil has been collected from eastern part of India (Odisha) and different percentages of Fly Ash (5, 10, 15, 20, 25 and 30 %) and Dolochar (5, 10, 15, 20, 25 and 30 %) were added to it, to predict the influence of these additives on compaction and consolidation characteristics of Expansive soil. Addition of both Fly Ash and Dolochar were found to decrease the index properties such as liquid limit, plastic limit, plasticity index, swelling index and enhancing the consolidation as well as drainage characteristics of Expansive soil. However, the maximum dry density of soil was found to decrease with addition of Fly Ash and increase with addition of Dolochar.  相似文献