Showing 4 results for Vaseghi
S. Vaseghi, M. Afyuni, H. Shariatmadari, M. Mobli,
Volume 7, Issue 3 (fall 2003)
Abstract
Excessive application of sewage sludge leads to the accumulation of potentially toxic elements in soils. The objective of this greenhouse study was to examine the DTPA–extractability of Fe, Zn, Cu, Mn, Pb, Cd, Ni, and Co in relation to soil pH and to investigate the concentrations of these metals in corn (Zea mayz). The study was conducted using a factorial experiment in a completely randomized design with three replications. Sewage sludge was applied at 0, 50, 100, and 200 t/ha on four soils [Langaroud (pH= 4.8), Lahijan (pH= 5.7), Rasht (pH= 6.8), and Isfahan (pH= 7.9)]. Application of sewage sludge significantly increased DTPA-extractable Fe, Zn, Cu, Pb, Cd, and Ni in all soils. The increasing effect was in accordance with sludge level. Langaroud soil had the highest and Isfahan soil the lowest levels of DTPA-extractable metals. Application of sewage sludge increased plant growth and metals in the foliage of corn plants. The metal concentration in corn tissues also increased with decreasing soil pH. Overall, the application of sewage sludge as an organic material, particularly in acid soils, may increase availability of heavy metals, which may, in turn, result in soil pollution. Therefore, addition of sewage sludge to soils should be managed on the basis of the changes in soil heavy metal concentration.
E. Vaseghi , A. Esmaeili,
Volume 12, Issue 45 (fall 2008)
Abstract
This study used a Ricardian approach to measure the impact of climate change on Iranian wheat production and analyzed potential impacts of further climate changes. The study utilized time series data for the period 1984-2004 pooled over 17 provinces. Results showed that climate change has significant nonlinear impacts on net revenue per hectare of wheat in Iran. The results also showed that rise in temperature and reduction in rainfall by the year 2100 will cause the reduction in land value by 41 %, because of increased greenhouse gas emission.
M Bakhshoodeh, E Vaseghi,
Volume 13, Issue 48 (7-2009)
Abstract
In this study, marketing situation, problems and services of Dutch Roses was investigated in Isfahan province as a main rose producing region in Iran. In this context, marketing margin, share of marketing agents in marketing margin, marketing cost coefficients and marketing efficiency were calculated and marketing path and marketing services of roses flower including harvesting, transportation, packing, sorting and standardization in major path were investigated. The data used in this study were gathered through completing questionnaires from 38 producers, wholesalers (cut flowers distributors) and retailers (flower sellers) and by interviewing four consulting companies in Dutch Roses production and marketing. The results indicated that 56.5 percent of producers are only engaged with production activities and not exporting flowers to either foreign countries or the other provinces in the country. In the main path, average coefficient of technical efficiency (78.17%) was found to be higher than that of price efficiency (34.67%) and based on the marketing efficiency, 108 Rial value added can be achieved from each 100 Rial marketing services cost..
S. Vaseghi, M. Valinejad, M. Afyuni,
Volume 21, Issue 3 (Fall 2017)
Abstract
Nitrogen use efficiency is relatively low in irrigated rice fields because of rapid N losses from ammonia volatilization, the nitrification, surface runoff, and leaching in the soil-flood water system. Since the plant N represents the total N supply of all sources, plant N status will be a good indicator of N availability to crops at any given time. Leaf colour chart (LCC) is a simple portable diagnostic tool, to determine the timing of N top dressing. LCC was developed to increase the N use efficiency at irrigated rice fields. A field experiment was carried out to compare the effect of N split application and LCC on the grain yield and agronomic and recovery efficiency of Fajr variety in 2009. The experiment was conducted in a randomized complete block design with 12 treatments in 3 replications on Fajr cultivar. Twelve treatments included control treatments (without nitrogen fertilizer) and 45, 90, 135 kg N ha-1 for three times each and two treatments included LCC treatments 4 and 5. As a result, all treatments showed significant (p=0.05) grain yield increase in comparison to control. Increased yield was observed up to 135 kgN/ha (55.2%). Grain yield of LCC treatments was higher than split treatments. LCC treatment 5 had higher AE, RE, PE, PFP and IE than LCC 4 and fixed – 135 at the less N rate in all fields. Therefore, the results of different fertilizer treatments showed that the LCC treatment 5 with maximum grain yield, agronomic, physiological, internal and relative efficiency factors can be considered as the best management method for using nitrogen fertilizer and preventing from excess use of nitrogen fertilizer in Fajr cultivar.
