K. N. Tiwari

Effect of drip irrigation on yield of cabbage (Brassica oleracea L. var. capitata) under mulch and non-mulch conditions

The experiments were conducted on the lateritic sandy loam soils of Kharagpur, West Bengal, India during middle of September?January for 3 years (1997?2000) to evaluate the economic feasibility of growing cabbage crop under drip irrigation with mulches. Actual evapotranspiration for cabbage crop was estimated by using the modified Penman method and net daily irrigation requirement was estimated after subtracting effective rainfall. Estimated irrigation requirement was supplied by a 4 l h-1 emitter for four plants with the drip irrigation system being operated from 70 to 101 min per day during the crop season. The average seasonal water requirement of crop was estimated to be 400 mm. The yields of the cabbage under 25 m thick black plastic mulch (PM) were studied using three levels of drip irrigation which applied 100% (VD), 80% (0.8VD) and 60% (0.6VD) of the estimated irrigation requirement. The yield response under two organic mulches, rice husk with drip (VDH) and paddy straw with drip (VDS) were also studied. For comparison, furrow irrigated (VF) treatments were used and the study revealed 62.44% higher yield in case of drip (VD) as compared to furrow irrigation. Even higher yields were obtained for drip irrigation with PM (VD+PM), 111.72 t ha-1 as compared to 106.68 t ha-1 for (VD). The treatments VDH and VDS showed, respectively, 2.05 and 1.18% higher yield when compared with drip (VD) alone. The net seasonal income was estimated to be highest as US

Prioritization of watersheds using morphometric parameters and assessment of surface water potential using remote sensing

4333 in case of treatment VD+PM. The highest benefit?cost ratio of 8.17 was obtained for furrow irrigation (VF) followed by 6.99 for drip (VD). The net profit per mm of water used was obtained to be highest (US

Response surface analysis of tomato production under microirrigation

16.51) in case of drip irrigation (0.6VD) followed by US

Vertical accuracy of digital elevation model from Shuttle Radar Topographic Mission – a case study

16.32 under the treatment 0.6VD+PM. The highest yield per unit quantity of water used was 427.04 kg ha-1 mm-1 for the treatment 0.6VD+PM. The study reveals that drip irrigation has a definite role in increasing the productivity of cabbage. Author Keywords: Drip irrigation; Cabbage; Plastic mulch; Rice husk; Paddy straw; Benefit?cost analysis

Evaluation of Field Level Adaptation Measures Under the Climate Change Scenarios in Rice Based Cropping System in India

In the present study, prioritization of sub-watersheds was carried out on the basis of sediment production rate. Further, basic hydrologic information such as peak rate of runoff and annual surface water potential were also assessed for the study watersheds and these are essential requisites for effective watershed management. The 10 sub watersheds of Tarai development project area are selected for the present study. Morphometric parameters pertaining to study area are used in the estimation of sediment production rate. The sediment production rate in the study area varies between 2.45 to 11.0 ha-m/100 km2/year. The remote sensing data has been utilized for generating land use/land cover data which is an essential prerequisite for land and water resource planning and development. The remote sensing data can especially play significant role in collection of real time information from remote areas of river basins for generation of parameters required for hydrologic modeling.

Effect of spatial resolution on watershed characteristics and the ANSWERS model hydrological simulations for a small watershed

Abstract Response surface methodology (RSM) was used to evaluate the effect of irrigation level, fertigation level and frequency of microirrigation on the yield of tomato ( Lycopersicum esculentum Mill , cv. Dhanashri). Optimization was performed to assess maximum yield and minimum input cost. Computer generated response surfaces, canonical analysis and contour plot interpretation revealed that drip irrigation scheduled at every second day frequency with irrigation level 79% of ET and fertigation at 96% of recommended dose resulted in maximum yield of tomato. It saved water to the tune of 21% and increased yield up to 27%. Further, considering the advent of mechanically moved portable drip sets, with every second day irrigation approximately 50% saving on initial investment of drip set can be achieved as the same set will irrigate double the area.

Quantification of transpiration and evaporation of okra under subsurface drip irrigation using SIMDualKc model during vegetative development

Vertical accuracy of the processed Shuttle Radar Topographic Mission (SRTM) digital elevation model (DEM) was evaluated using spot height as well as reference DEM. Terrain dependency of error was also explored in relation to elevation, slope and aspect of the terrain. The positive mean error (6.77 ± 1.79 m) indicated that the SRTM DEM was slightly underestimating the elevation and this pattern gradually increases towards higher elevation. The observed root mean square error (RMSE) (27.58 ± 4.22 m) for the region do not fulfill the 16 m RMSE specification of the SRTM mission. High magnitude errors are typical to steep slope (due to overestimation) and in stream valley (due to underestimation). The magnitude of residuals for NW, W and SW facing slope was smaller as compared to their complementary angle. Results also indicated a S and NE components in SRTM DEM because of underestimation and overestimation of elevation, respectively.

Impact of Abandoned Opencast Mines on Hydrological Processes of the Olidih Watershed in Jharia Coalfield, India

With the rise in population, under future scenarios, global food demand is expected to increase. Biotic and abiotic factors such as climate change are threat to food security owing to its variability, occurrence, duration and magnitude of extreme events. Since, the climate change is unequivocal, the adaptations and mitigations for sustainable agricultural production can minimize its negative impact on agriculture and improve food grain productivity. The grain yield of rice and peanut was simulated for the base period (1969–1999) and future periods 2020 (2011–2040), 2050 (2041–2070) and 2080 (2071–2100) under A2 and B2 scenarios of HadCM3 Global Climate Model. Under the A2 and B2 scenarios, the yield of both rice and peanut declined from base period to the future periods 2011–2040, 2041–2070 and 2071–2100. The cultivar ‘IR 36’ was found to be more sensitive to rising temperature under future climate scenarios as compared to ‘Swarna.’ The yield decline for future climate scenarios increased with locations from higher (Kharagpur and Cuttack) to lower latitude (East Godavari and Vizianagaram). Earlier transplanting time of rice compared to normal (15 July) and sowing time of peanut from normal (9 February) increased the simulated yields of rice-peanut system at higher latitude and reduced the yield loss at lower latitude in future climate scenarios. Delayed planting caused maximum grain yield reduction of the cropping system in future climate scenarios at all the locations.

Okra Crop Response Under Subsurface Drip and Conventional Furrow Irrigation with Varying N Fertilization

The present study was undertaken to investigate the effect of cell size variation on watershed characteristics and hydrological simulations of the physically based distributed parameter Areal Non point Source Watershed Environment Response Simulation (ANSWERS) model. The study is carried out in Banha watershed located in Upper Damodar catchment, Jharkhand, India having 16.13 km2 area (with average slope of 1.91%.) using Digital Elevation Model (DEM), GIS and remote sensing techniques for automatic extraction of the model input parameters. The spatial resolution (cell size) variation from 30m to 150m with incremental step of 30m influences the accuracy of watershed characteristics extracted from DEM. The flow path length and average watershed slope decreased by 53.71% and 20.94% respectively due to variation in cell size. Important watershed parameters such as drainage area, stream network, slope etc. were extracted most accurately automatically with variations less than 10% using DEM of 30m resolution through EASI/PACE and IDRISI GIS. Land use and land cover information generated from Indian Remote Sensing Satellite (IRS-1B, LISS-II) data at 30 m resolution resulted in overall classification accuracy greater than 88%. The watershed hydrological data from fifteen storms of 1995 and 1996 were used for the ANSWERS model cell size sensitivity study. The runoff, peak flow and sediment yield simulations by the model decrease as cell size increases from 30 m to 150 m. The model simulated peak flow at acceptable accuracy for 30 m cell size. The runoff and sediment yield simulations are not observed to be significantly different from the observed values up to 120 m cell size.

Assessment of surface water potential using morphometry and curve number-based approaches

ABSTRACT Knowledge of productive and nonproductive water loss of okra [Abelmoschus esculentus (L.) Moench] is essential during water scarcity, and for assessing links between yield and water use. The study was conducted using subsurface drip irrigation to evaluate okra transpiration and evaporation using the SIMDualKc Model. The model computed soil evaporation was 132.89 and 157.84 mm, respectively, whereas transpiration was 381.22 and 340.36 mm in 2016 and 2017, respectively. Pod yield of okra was 12.1 and 12.5 t∙ha−1; dry biomass above ground was 5.7 and 4.9 t∙ha−1 in 2016 and 2017. Biomass above ground and fresh pod yield of okra indicates that high water deficit before harvesting pods causes a depression in fresh fruit yield and decreases total pod yield. Several water deficit occurrences during the growing period lowers total transpiration and adversely impacts okra dry biomass above ground. The SIMDualKc Model is capable of quantifying evaporation, transpiration and other water balance components. It is an effective tool for assessing and predicting the impact of water deficit on plant development and yield and can be used to identify the correct irrigation strategy for maximizing crop production.