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Thesis

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2013 - 20185
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Subject: Soil and Water Engineering × End date: 2019 × Start date: 2010 × Type: Thesis × Thesis Type: Ph.D ×
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Now showing 1 - 5 of 5
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    ThesisItemOpen Access
    Design and Evaluation of Automated Drip Irrigation System
    (Punjab Agricultural University, Ludhiana, 2018) Sandeep Kumar; Jain, A.K.
    An automated drip irrigation system (ADIS) was designed and evaluated in collaboration with JISL, Jalgaon, (Maharashtra). To optimize the design parameters of the system, two types of drip irrigation systems were considered, viz. wired based automated drip irrigation system (IS1) and wireless automated drip irrigation system (IS2). The experiment was carried out for two seasons on tomato crop (Abhinav, Syngentha) using two water sources viz. ground water and treated fruit processing waste water. The study revealed that the quality parameter of tomato was better for treated fruit processing water (WQ2) in comparison of ground water (WQ1) quality. Based on the optimization of ADIS, it was found that the irrigation system and water quality significantly affect the plant height, number of leaves, number of branches, number of fruits and yield. The wireless based irrigation system (IS2) with treated fruit processing waste water (WQ2) was found as best combination. The maximum tomato yield of 37.79 ton/ha was obtained with wireless based irrigation system with pressure compensating drippers (PC) for treated fruit processing waste water (WQ2). Economic analysis has been done to check the commercial viability of the automatic drip irrigation system. The benefit cost ratio for wired based irrigation system was found to be as 1.44 without subsidy and 1.77 with 50 percent subsidy, whereas, benefit cost ratio for wireless irrigation system was found to be as 1.56 without subsidy and 1.90 with 50 percent subsidy. Breakeven point for wired based irrigation system has been achieved after 14 years without subsidy and 10 years with 50 percent subsidy, whereas, breakeven point for wireless based irrigation system has been achieved after 10 years without subsidy and 5 years with 50 percent subsidy. Based upon the above study it was found that wireless irrigation system is more economical and best suited automated drip irrigation system to get higher net returns as compared to wired based irrigation system.
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    ThesisItemOpen Access
    Modeling Microclimate of Naturally Ventilated Greenhouse under Cropped Conditions in Soilless Media
    (Punjab Agricultural University, Ludhiana, 2018) Mahesh Chand Singh; Singh, J.P.
    A study was undertaken to develop mathematical models for simulating microclimate of a naturally ventilated greenhouse under cropped conditions and develop the optimal operating microclimatic conditions for drip fertigated cucumber crop in soilless media. Cucumber crop was grown in coco-peat in a split plot design in three replicates during two successive growing seasons of 2016-17. The treatments included three levels of fertigation in main plots viz. F1=100.0%, F2=85.0% and F3=70.0% of complete nutrient solution under optimal microclimatic conditions. Sub-plots included cultivars viz. V1 (Kafka), V2 (Multistar) and V3 (PBRK-4). Mathematical models for standardizing the temperature of greenhouse cover, air, plant and growing media were developed, calibrated and validated in Simulink MATLAB with a mean model efficiency and coefficient of determination values of 94.7% and 0.96 respectively. Mathematical models of sensible and latent heat balance were developed to predict vertical air temperature profile and vapour pressure and solved analytically. Models for predicting saturation vapour pressure (SVP), actual vapour pressure (AVP) and vapour pressure deficit (VPD) from internal and external climates were developed and solved in Simulink MATLAB. Further, models for predicting temperature of air, leaf, plant root-zone and relative humidity were also developed from external climate. The average fruit yield was obtained in the range of 2.4-3.5 kg plant-1 and 3.3-4.4 kg plant-1 with and without fruit thinning having lowest and highest yield under treatments F3V3 and F1V2. Crop water use efficiency (CWUE) was found in the range of 60.4-86.3 kg m-3 and 84.5-108.9 kg m-3 with and without fruit thinning respectively. The average benefit cost ratio (BCR) was computed to be 1.91 and 1.54 with and without subsidy respectively without fruit thinning. However, BCR decreased by 23.7% and 23.8% with and without subsidy respectively with fruit thinning. The developed models were calibrated and validated separately for both growing seasons and a good agreement was observed between the model predictions and observed data. Thus, the developed models successfully simulated the greenhouse microclimate. Based on microclimate modeling, the desirable range of Tapc, TL, Trz, Eapc, Irad and VPD were worked out to be 22.0-27.0°C, 20.5-25.1°C, 16.9-22.9°C, 60.0-85.0%, 100.0-169 Wm-2 and 0.53-1.10 kPa respectively for optimal plant growth and development.
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    ThesisItemOpen Access
    Impact of resource conservation interventions on water and sediment yield in a watershed of Shivalik
    (PAU, 2015) Yangchan, Jigmet; Jain, A.K.
    Soil and water are considered as one of the world‟s limited and non-renewable resource. Soil erosion by water is being increasingly recognized as a problem across the world. The objective of this study was to assess the impact of resource conservation interventions on water and sediment yield in a watershed. Morphometric analysis of Sukhna Lake watershed covering Chandigarh, Punjab and Haryana was carried out by using GIS technique. This analysis shows that the basin has a dendritic pattern with fifth order stream. Bifurcation ratio, drainage density, drainage texture, elongation ratio and relief ratio value of the watershed confirm that the geologic structures do not distort the drainage pattern. The area was impermeable subsurface having sparse vegetation, hilly relief and steep slop es with very fine texture cause prone to soil erosion. Impact analysis for six scenarios have indicated that in the initial period (1958-70) rainfall was less but runoff percentage was 22% of rainfall, no soil conservation measures were present due to which heavy soil loss of 150 ton/ha/yr, where as in 2013 rainfall was high but runoff percentage significantly decreased to 7.8% of rainfall due to increased number of structures over 190 as a result the sediment yield also decreased to 5 ton/ha/yr. This study shows that an adequate soil conservation measure exists, as result creations of new strictures are not required. In order to retain the sediment yield, the structures need regular maintenance. High evaporation rate in the region causes drying of the lake as the capacity has reduced from 10.74 million cubic meter (MCM) initially to 5.24 (MCM) at present, almost 50% of the lake‟s capacity reducing the depth of lake. In case of afforestation preference should be given to drought resistant species and deep rooted plantation. However the sediment yield has reduced to 5 ton/ha/yr but from the catchment of 4284 ha it is a huge amount settling down in the lake and reducing its capacity. In such case periodic desilting has to be taken up once in 2-3 years. To maintain the required water level in Sukhna Lake on a sustainable basis throughout the year, strategies must be made to divert the water from the other adjacent catchments.
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    ThesisItemRestricted
    Modelling the impact of climate change on groundwater resources in central Punjab
    (PAU, 2013) Samanpreet Kaur; K.G. Singh
    A study was planned to assess the impacts of climate change on groundwater resources in Ludhiana district under PRECIS A1B climate change scenario by linking the outputs of climate, soil-water-vegetation and groundwater models using GIS. Bias correction of climate data was done by correction functions, developed using modified difference, approach at daily time scale for rainfall and at monthly time scale for Tmax and T min. The methodology consists of development of simulation zones by overlaying soil, drainage, canal and landuse thematic maps in GIS and estimating water balance components using CropSyst and well defined norms. The groundwater draft for individual simulation zones was computed on the basis of landuse, irrigation requirement and rainfall conditions. The spatial distribution of recharge and groundwater draft was mapped to GIS and was provided as input to groundwater model. The results showed that temperature and rainfall would be increased by 2.4°C, 315 mm in MC (2021 - 2050); and 5.1°C and 465 mm in EC (2071-2098), respectively. During kharif season increase in RF would be 28.0% in MC and 52.0% in EC compared to that in PTS (1971-2010). The corresponding values during rabi would be 82.3% and 88.6%, respectively. As a consequence of increased precipitation, the irrigation requirements in MC and EC would decrease by 46% and 45% during kharif; and 21% and 34% in rabi, respectively. However, the potential groundwater recharge would be reduced by 23.1 and 4.2 per cent in kharif, and increased by 39.1 and 79.6 per cent in rabi during MC and EC, respectively. The average groundwater levels would decrease by 2.2 m in 2050 and increase by 4.8 m in 2098, compared to base year of June 2000. The results presented here should be interpreted as trends and not as accurate quantitative predictions of the hydrological changes as there are numerous sources of uncertainties associated with climate change prediction.
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    ThesisItemRestricted
    Simulation of heating and cooling of agricultural greenhouse using geothermal energy
    (Punjab Agricultural University, Ludhiana, 2016) Namgial, Deldan; Aggarwal, Rajan
    The Earth Tube Heat Exchanger (ETHE) system was installed at the research field of Department of Soil and Water Engineering, Punjab Agricultural University, Ludhiana, India. The soil temperature was monitored upto 3.5 m from April 2013 to March 2014. The ETHE was designed and installed based on deep soil temperature and heating load of greenhouse. The ETHE consists of 42 m long PVC pipe of 0.25 m diameter buried at 3.5 m depth. The air was circulated with belt driven force drive centrifugal blower (radial blade) attached with 3 phase 10 hp motor. The ETHE was operated at velocity ranging from 2.3 to 24 m/s under open and closed system for winter heating from Oct 2014 to Feb 2015. It was also operated under open, closed and naturally ventilated system for summer cooling from April to June 2015. The thermal parameters viz. heating/cooling potential, Coefficient of Performance (COP) and tube efficiency were evaluated at different velocities and durations. In all ETHE systems it was observed that as velocity increased the temperature difference between inlet and outlet decreased. The mean heating potential, COP and tube efficiency under open system was higher than closed system in each set of velocity during peak winter. But the cooling potential, COP and tube efficiency under closed system was higher than open and naturally ventilated system during peak summer. The cooling potential, COP and tube efficiency during peak summer were higher than peak winter. However, the performance of greenhouse coupled with ETHE during peak winter was better than peak summer. Therefore, the study revealed that thermal parameters are not proportional to performance of greenhouse coupled with ETHE. The ETHE inlet and outlet temperatures recorded during ETHE operation were used to calibrate and validate the FLUENT model. The low value RMSE and percent error and high correlation coefficient during validation indicate reasonably accurate simulation of ETHE outlet temperature by the model. The parametric analysis revealed that ETHE performance increased with decreased in velocity and diameter of pipe and increased in buried depth and length of pipe.