Economics and energetics in hybrid sunflower cultivation as influenced by irrigation and fertilizer management practices

The objective of the study was to assess economic feasibility and environmental sustainability in sunflower cultivation as influenced by irrigation and fertilization. A field experiment was conducted during the winter (November-March) of 2011-12 and 2012-2013 in farmer’s field at Madandanga under Chakdaha block of Nadia district in West Bengal (23°22.221'N latitude and 88°22.221'E longitude with an altitude of 12 m above mean sea level), under sub-humid subtropical climatic condition. The crop irrigated thrice (I30/60/80) outperformed other crops which had reduced moisture (I30 and I30/60) in respect of gross revenue (GR). Irrespective of irrigation levels, application of N80P40K40B1.5S25 treatment paid the highest additional GR over RDF. The higher incremental cost-benefit ratio (ICBR) for ‘Aditya’ was observed with N80P40K40B1.5 at all irrigation levels. Estimated energy indices revealed that net energy gain (NEG) was the highest with the supply of N80P40K40B1.5S25 at all irrigation levels. However, maximum values of energy ratio (ER) and energy productivity (EP) were recorded with N80P40K40B1.5 while total specific energy (SE) was higher with N80P40K40S25 for all irrigation levels. Recommended dose of fertilizer (N80P40K40) was observed to be the most energy-intensive treatment with higher energy intensiveness (EI) values. The treatment N80P40K40VC5 was found to be the most energy-efficient treatment with lowest energy intensiveness (EI) values at all irrigation levels, closely followed by the N80P40K40B1.5S25 treatment.

Evaluating the parameters of a mobile maize dryer in practice

The method of drying maize for grain has been recently employed on a large scale in the Czech Republic not only thanks to new maize hybrids but also thanks to the existence of new models of drying plants. One of the new post-harvest lines is a plant in Lipoltice (mobile dryer installed in 2010, storage base in 2012) where basic operational measurements were made of the energy intensiveness of drying and operating parameters of the maize dryer were evaluated. The process of maize drying had two stages, i.e. pre-drying from the initial average grain humidity of 28.55% to 19.6% in the first stage, and the additional drying from 16.7% to a final storage grain humidity of 13.7%. Mean volumes of natural gas consumed per 1 t% for drying in the first and second stage amounted to 1.275 m3 and 1.56 m3, respectively. The total mean consumption of electric energy per 1 t% was calculated to be 1.372 kWh for the given configuration of the post-harvest line.

Productivity growth in the paper and paperboard industries: a variable cost function approach

Annual indices of total productivity growth were calculated for the paper and paperboard industries of the United States between 1958 and 1981. The procedure relied on the hypothesis that each industry minimizes variable costs, conditional on the level of the remaining inputs. The variable cost functions revealed short-run economies of scale but long-run diseconomies, suggesting inefficient capacity expansion. Derived demands for energy, labor, and materials were inelastic. Demand for energy was much more responsive to price than labor and materials. There were substantial substitution possibilities between energy and materials and between labor and materials, but none between labor and energy. The productivity indices that were computed showed a slightly increasing rate of productivity growth between 1958 and 1973, with a marked slowdown thereafter. This slowdown was explained by the rise in the price of energy. Average productivity growth was three to four times faster in the paper than in the paperboard industry between 1958 and 1981. This difference was partly explained by higher energy intensiveness and lower labor productivity growth in the paperboard industry.