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Theses

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2004 - 20084
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Subject: Agricultural Meteorology × End date: 2009 × Start date: 2004 × Type: Thesis ×
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    ThesisItemOpen Access
    Evapotranspiration studies on chickpea (Cicer arietinum L.) and moong (Vigna radiata L. Wilczek) in a mollisol of tarai region of Uttaranchal
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2006-05) Ahmed, Gulrez Jahangeer; Suman Kumar
    This study was conducted at the Crop Research Centre of G.B. Pant University of Agriculture and Technology, Pantnagar for quantifying evapotranspiration losses of chickpea and moong under Uttaranchal tarai conditions and to select some suitable mathematical methods based on meteorological parameters for estimating chickpea and moong ET of this type of agroclimatic conditions. Evapotranspiration of chickpea and moong were measured with weighing type lysimeters. Data on pan evaporation measured with USWB class A pan evaporimeter and various chickpea parameters for the corresponding period were collected from Meteorological Observatory. Evapotranspiration of chickpea and moong was also estimated by using mathematical methods of Thornthwaite, Turc, Stephens-Stewart, Jensen-Haise, Blaney-Criddle and Modified Penman. The relationship of measured ET with pan evaporation and ET estimated by different mathematical methods was studied by linear regression and simple correlation. It can be concluded that the evapotranspiration of chickpea and moong under tarai conditions is about 342.1 mm and 340.8 mm respectively. The average total rainfall during chickpea and moong season is 119.4 mm and 1028.4 mm respectively. Thus supplementary irrigation is required during chickpea season due to low rainfall but not for moong season due to sufficient rainfall. As the Pan evaporation did not give accurate estimate of chickpea and moong ET, both on seasonal and as well as weekly basis. So Pan evaporation does not seem to be good criteria for ET estimation in chickpea and moong in this region and Modified Penman and Jensen-Haise methods are very suitable for estimation of ET in this tarai region of Uttaranchal.
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    ThesisItemOpen Access
    Effect of microbial inhibitors on emission of nitrous oxide from paddy fields
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2005-08) Srivastava, Aditi; Bharadwaj, Venkatesh
    The hazards of increasing concentration of green house gases in the atmosphere are becoming visible day by day. Global warming of the earth is taking place at an unprecedented rate and climates all over the world are fast changing. This unusually higher rate of change has been attributed to nothing but human intervention into the processes of nature. N2O concentration in the atmosphere at present stands at 311 ppbv and is increasing at the rate of 0.25% per year. It has been reported to be contributing almost 5% to the total green house effect. Both unfertilized and fertilized soil have been found to be emitting N2O which is produced during denitrification and nitrification reactions taking place through soil microbes. In the present investigation, an attempt was made to develop techniques for mitigation of N2O evolved from soil by the use of microbial inhibitors without reducing yield of the crop under study (paddy). Effect of nine treatments were observed upon N2O emission as well as upon the plant growth parameters, yield attributes and yield of crop which was kept under submerged condition during the period of study. The treatments were control (no N, with crop), 100% NPK + Nitrapyrin, 100% NPK + Nitrapyrin + green manure (GM), 100% NPK + ECC, 100% NPK + ECC + GM, 100% NPK + Thiourea, 100% NPK + Thiourea + GM, 100% NPK + Dicyandiamide (DCD) and 100% NPK + DCD + GM which produced an average N2O flux rate of 0.21, 0.44, 0.39, 0.01, 0.43, 0.57, 0.38, 0.28 and 0.25 mg m-2 hr-1. Maximum inhibition of N2O emission was observed by 100% NPK+ECC treatment, but this treatment had a more or less adverse effect on plant growth as well as yield. The treatment, 100% NPK + Thiourea + GM had an extremely positive effect on plant growth as well as yield but its inhibitory effect on N2O emission was not found to be substantial in comparison to other treatments. However the treatment, 100% NPK + DCD + GM was found to fit both the roles perfectly. It was able to effectively control N2O emission rate from the soil while also maintaining the yield at a considerably higher level than other treatments.
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    ThesisItemOpen Access
    Evapotranspiration studies on wheat (Triticum aestivum) and soybean (Glycine max) in a mollisol of tarai region of Uttaranchal
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2004-07) Sunil Kumar; Suman Kumar
    This study was conducted at the Crop Research Centre of G.B. Pant University of Agriculture and Technology, Pantnagar for quantifying evapotranspiration losses of wheat and soybean under Uttaranchal tarai conditions and to select some suitable mathematical methods based on meteorological parameters for estimating wheat and soybean ET of this type of agroclimatic conditions. Evapotranspiration of wheat and soybean was measured with weighing type lysimeters. Data on pan evaporation measured with USWB class A pan evaporimeter and various wheat parameters for the corresponding period were collected from Meteorological Observatory. Evapotranspiration of wheat and soybean was also estimated by using mathematical methods of Thornthwaite, Turc, Stephens-Stewart, Jensen-Haise, Blaney-Criddle and Modified Penman. The relationship of measured ET with pan evaporation and ET estimated by different mathematical methods was studied by linear regression and simple correlation. It can be concluded that the evapotranspiration of wheat and soybean under tarai conditions is about 445.2 mm and 513.1 mm respectively. The average total rainfall during wheat and soybean season is 256.8 mm and 1187.9 mm respectively. Thus supplementary irrigation is required during wheat season due to low rainfall and also for soybean season during the years of low rainfall. As the Pan evaporation did not give accurate estimate of wheat and soybean ET, both on seasonal and as well as weekly basis. So Pan evaporation does not seem to be good criteria for ET estimation in wheat and soybean in this region and Modified Penman and Jensen-Haise methods are very suitable for estimation of ET in this tarai region of Uttaranchal.
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    ThesisItemOpen Access
    Study of crop-weather relationship and its impact on growth and yield of chickpea (Cicer arietinum L.) in mollisol of Uttarakhand
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2008-07) Singh, Shweta; Suman Kumar
    For the present study, the experiments were conducted at the Crop Research Centre of G.B. Pant University of Agriculture and Technology, Pantnagar with the objectives for quantifying evapotranspiration losses and the effects of temperature and relative humidity on the canopy of chickpea under tarai conditions, and to select some suitable mathematical methods based on meteorological parameters for estimating ET from chickpea. Evapotranspiration of chickpea was measured with weighing type lysimeter. Data on pan evaporation measured with USWB class A pan evaporimeter and chickpea parameters for the corresponding period were collected from Meteorological observatory. Evapotranspiration from chickpea was also estimated by using mathematical methods of Thornthwaite, Turc, StephensStewar, Jensen-Haise, Blaney-Criddle and modified Penman. Higher growing degree days 1810.4 was observed during 2005-06. Air temperature profiles at different stages indicate that temperature inside the crop canopy was lower than above canopy. The yield per hectare was higher during 2005-06 in comparison to 2006-07 due to favourable weather condition in 2005-06. Evapotranspiration of chickpea during 2005-06 and 2006-07 are about 416.5 and 475.6 mm, respectively. The average total rainfall during 2005-06 and 2006-07 were 18.2 and 275 mm, respectively. Thus, supplementary irrigation was required during crop season due to low rainfall. As the pan evaporation did not give accurate estimate of ET, both on seasonal and as well as weekly basis. Thus, the pan evaporation does not seem to be good criterion for the estimation of ET. Modified Penman method was found to be most very suitable for estimation of ET in tarai region of Uttarakhand.