Ranvir Kumar

Comparative performance of different crop production functions for wheat (Triticum aestivum L.)

SummaryExperiments were conducted for wheat (Triticum aestivum L.) grown in the lysimeters with controlled irrigation at Berlin (FRG) and in field plots at Hisar (India) under different climatic conditions. Crop production functions, relating crop yield with evapotranspiration with and without the consideration of the time of water deficit during crop growth period, were derived. The derived functions and those previously obtained by different workers were tested against the experimental data. There was a significant correlation of seasonal evapotranspiration with yield that was slightly higher for dry matter than for grain. The correlation, which was quite high for linear functions, was slightly greater for nonlinear functions. The correlation was also slightly improved if evapotranspiration for different growth stages was considered rather than total seasonal evapotranspiration. Since there apears to be no single equation that fits all of the conditions studied and since different equations lead to different conclusions, it is suggested that the crop production functions considering evapotranspiration at different growth stages be used with caution. In general the degree of sensitivity of grain yield and dry matter yield to water stress for wheat cultivar WH 283 grown in field experiments under semi-arid climate decreased in the order of crop growth sub-periods I (Sowing to heading), III (Milk ripe to ripe), and II (Heading to milk ripe). However, the sensitivity of the grain yield and dry matter yield to water stress for wheat cultivar Kolibiri grown in lysimeter experiments under humid climate decreased in the order of the growth sub-periods i.e. I, II, and III.

Evapotranspiration from wheat under a semi-arid climate and a shallow water table

Abstract Field experiments were conducted to study crop evapotranspiration and its relationship with Class A Pan evaporation for wheat cultivars WH-283 and WH-2009 grown in a semi-arid climate in sandy loam soils with shallow ground water table. The irrigation treatments were wet, middle and dry. The values of soil moisture at different soil depths, seasonal soil moisture depletion in crop root zone, and capillary contribution from ground water to crop root zone were different for different treatments and were influenced by rainfall pattern, irrigation, ground water table depth, and plant factors. The capillary contribution was lower under the dry treatment as compared to the wet treatment due to restricted plant growth and lesser capability of plants to extract water under dry treatment. The cumulative evapotranspiration increased at a decreasing rate with time from sowing to harvesting and the values were higher for wheat cultivar WH-283 as compared to cultivar WH-2009. The seasonal evapotranspiration varied from 163.6 to 382.6 mm for different treatments. The ratio of actual evapotranspiration to Class A Pan evaporation ( E a E pan ) for different crop growth stages increased from 0.1 at germination to the maximum value and then decreased towards the crop ripening. The maximum values of the E a E pan ratio varied from 0.61 to 1.8 for different treatments and occurred earlier for the wet as compared to the dry treatments. The values of the ratio and the actual evapotranspiration for different wheat cultivars were influenced by rainfall pattern, irrigation, ground water table depth, and soil and plant factors in addition to Class A Pan evaporation. Therefore, the values of the E a E pan ratio can not be generalized for a particular agro-climate and should be used with caution in irrigation planning.

Drainage disposal and reuse simulation in canal irrigated areas in Haryana

Nearly 60 per cent of the geographical area of Haryana state in Indian Union is underlain by saline ground water. The intra-basin transfer of surface water in the early sixties for irrigation has disturbed the hydrodynamic equilibrium resulting in waterlogging and salinization in large parts of the state. The existing inland drainage basin conditions did not permit the disposal of drainage effluent. The reuse system was therefore, integrated with the drainage system. A model RESBAL was coupled with the calibrated and validated on-farm water management model FAIDS and run for eight years to optimally design a series of connected reservoirs for the disposal of drainage effluent from an area provided with a subsurface drainage system. The possibility of the reuse of the disposed water for irrigation, aqua culture and salt harvesting was also studied comprehensively in order to maintain proper salt balance in the root zone.

A groundwater model for simulating the rise of water table under irrigated conditions

Abstract A groundwater simulation model is used to predict the dynamic behaviour of the water table in response to groundwater pumpage and net recharge in a part of the Lower Ghaggar basin, Haryana, India. The pumped water is proposed to be used together with canal water for irrigation of crops and for drinking water demands considering the quality constraints.

Sub-surface water regime related to landform studies through satellite images

Based on the visual interpretation of satellite (Landsat) false colour composite imagery, the entire Haryana State is divided into eleven landform units. Seven major landform units are studied in details with respect to water table fluctuation, ground water quantum and draft. The studies reveal that usable recharge and draft per unit area are maximum in case of area of water seepage and periodic flooding followed by Yamuna and Ghaggar flood plain and upper alluvial plains with occasional sand dunes. The minimum recharge and draft are observed in case of dune areas.