Showing 7 results for Shafie
M. Bakhshoodeh, H. Shafiei,
Volume 10, Issue 3 (fall 2006)
Abstract
Evaluating different aspects of government policy in terms of their indirect and welfare effects has been always of interest. In this study, the effects of gauranteed purchasing policy on land under cultivation and yields of cotton, potatoes and onions were investigated in Fars province. For this purpose, a Nerlove model was applied to time series data of 1972-02 after testing their stationary to estimate the cultivated lands and yields functions of these products. The use of protection rates as explantory varrables is one of the interesting characteristic of such a model. Although the results were not similar for all the products, the indication is that the policy has not had significant influence on the land areas and yields of cotton, potatoes and onions. However, taking into account that the policy has been recentely commenced in Fars, and that the policy takes time to become effective, the policy may result in different outcomes in the long run.
M. Shafiei, H. Ansari, K. Davari, B.ghahraman,
Volume 17, Issue 64 (summer 2013)
Abstract
Application of conceptual hydrological models is an important issue in watersheds for researchers, especially in arid and semi-arid regions. The hydrological behaviors are complicated in such watersheds and their calibration is more difficult. In this article, the conceptual and semi-distributed SWAT model is used for a semi-arid Nishabour watershed with 9350 km2 area. Streamflow simulation is considered for 8 years. Nishabour watershed modeling led to 22 subbasins and 146 Hydrologic response units. SUfI2 approach is used for calibration and uncertainty analysis of watershed modeling. Results showed that calibration and validation of watershed model is not satisfactory, because of uncertainties in conceptual model such as dam structures, and land subsidence. Another reason is related to the complexity of hydrological system in arid regions which has simplified in hydrological models. Moreover, the complex behavior between runoff and subsurface flow in low depth of rainfall events usually effects in hydrological simulation results. Finally, it concluded that we cannot rely on conceptual hydrologic models with different sources of uncertainty without including them in hydrological modeling at arid and semi-arid watersheds.
N. Shafiee, H. Shirani,
Volume 17, Issue 66 (winter 2014)
Abstract
Copper is considered as one of the most important nutrient elements for plants. If its contents are concentrated higher than the standard value it can be considered as a pollutant element. The content of absorbable copper in the area around Sarcheshmeh copper mine can be significantly high. In this study, samples of soil were collected in summer through a particular sampling method with chimneys of Sarcheshmeh plant as the center of sampling area within a radius of 6km, in three different directions (Rafsanjan, Sarcheshmeh City and Sarcheshmeh mine) and. The total concentration of absorbable copper and some chemical properties of soil (i.e. pH and EC) were measured for 122 surface samples (depth of 0 to 35 cm). There was a significant negative regression between pH and total absorbable copper content, and a significant negative regression was observed between EC and total absorbable copper content. The best fitted model was spherical model, and Ordinary Kriging was applied to map the absorbable copper content. Results showed that most concentration of copper occurred in the Rafsanjan direction. Also, regarding wind orientation which blows towards Rafsanjan, the chimneys probably have a significant effect on increasing copper content in Rafsanjan moreover, the copper content is substantially higher around chimneys than other areas. Also, transition of copper elements from chimneys by wind can be significant up to 4 km from Sarcheshmeh plant.
M. Rezvani, M. Shafiezadeh,
Volume 19, Issue 71 (spring 2015)
Abstract
Nowadays, due to the effective role of nitrogen fertilizer in growth, yield and crop quality, farmers apply large amount of chemical fertilizers. High application of nitrogen fertilizers has caused soil and water pollution and environmental dangers, higher nitrate accumulation in plant, and different disease risks in human and livestock. In order to investigate the effects of nitrogen and cycocel application effects on soil nitrate pollution and agronomic traits of rice, an experiment was arranged in split plot based on a completely randomized block design with three replicates at Sari region (north of Iran) in 2010. The main factor was nitrogen in four levels and cycocel was considered as a sub factor in three levels. Results showed that maximum and minimum plant height and fourth internodes bending moment were obtained in 0 and 150 kg N ha-1, respectively. Higher filled spikelet percentage per panicle, grain yield and harvest index were obtained in 100 kg N ha-1 application. Application of N up to 150 kg N ha-1 increased soil nitrate by 44.7 percent. As cycocel application decreased, the plant height and panicle length were reduced, but tiller number per plant, filled spikelet percentage per panicle, and grain yield were increased.
L. Kashi Zenouzi, Sh. Banej Shafiee, A. A. Jafari,
Volume 20, Issue 76 (Summer 2016)
Abstract
In this study the effect of temperature, evaporation or evapotranspiration, precipitation, hillside direction and altitudinal classes, texture and acidity of soil on organic carbon content in the depths of 15 and 45 cm were evaluated. Paired t-test results showed that there is a significant difference between measured parameters in two soil depths. After preparing required data and processing them, outlier's data were removed. Then, base maps for each of the information layers were prepared by Arc GIS9.3 software and all relatd information fit together by overlapping them. Pearson correlation between environmental factors and soil organic carbon values were calculated and it was found that in the depth of 15 cm, the correlation between soil organic carbon values and two environmental factors including temperature and altitude were significant at the level 0.01. As well the results of statistical analysis by using principal component analysis (PCA) method showed that the factors temperature, evaporation (1%), and silt and clay (5%) have had a significant effect on the amount of soil organic carbon. The first, second, and third axes with eigenvalues of 98/4, 78/3 and 92/1, respectively, explained the values 0.33, 0.25, and 0.13 % of correlation between organic carbon and environmental data.
M. Nadi, A. Golchin, E. Sedaghati, S. Shafie, S. J. Hosseini Fard, G. Füleky,
Volume 21, Issue 1 (Spring 2017)
Abstract
Soil organic matter is the largest source of organic carbon in the soil surface which played an enormous role in restoring balance, environmental sustainability, soil elements and climatic conditions. Organic materials influence physical, chemical and biological properties of soil and thus soil fertility directly and indirectly. The amount, type and composition of organic matter are different in different soil and climatic conditions. Different soil components can hold different combination of soil organic matter. In this study soil samples were collected from virgin, Populus and Alnus forests from Guilan Province, Iran. The amount of organic matter in the original samples and sand, silt and clay fractions were measured and the quality of organic carbon (13C) and hydrogen (1H) were determined in fractions by Nuclear Magnetic Resonance. Based on the results the amount of organic carbon in the original samples of Alnus forest was highest. among fractions, clay had the highest amount of organic carbon. The result of Nuclear Magnetic Resonance showed presence of different aliphatic and aromatic carbons and hydrogen in different samples. Virgin forest had the highest proportion of alkyl to oxygenated alkyl carbon ratio and Alnus forest showed the highest ratio of aliphatic to aromatic carbon,. Both mentioned ratios was higher in clay fraction than other two fractions.
H. Shekofteh, A. Masoudi, S. Shafie,
Volume 22, Issue 3 (Fall 2018)
Abstract
Soil quality is the permanent soil ability to function as a live system within ecosystem under different land uses. Investigating the impact of land use type on soil quality indicators could help to distinguish sustainable managements and therefore, to inhibit soil degradation. In order to evaluate the effect of different land uses on soil quality indicators, a research based on a randomized complete design in Rabor region, Kerman Province, Iran, was conducted. A total of 104 samples were taken from the soil surface (0-15 cm) of four land uses including: pasture (28 samples), forest (25 samples), agronomy (27 samples) and garden land use (24 samples). Soil quality indicators were measured as: soil organic matter, particulate organic matter, and bulk density, plant available water capacity, S index, cation exchange capacity (CEC), electrical conductivity (EC), soil pH, and phosphatase enzyme. According to the results, land use types had a significant effect on all indicators except S index at 1% probability level. The maximum amount of soil pH, bulk density and phosphatase enzyme was obtained from forest land use. On the other hand, the maximum amount of the other indicators was attained from the garden land use. Totally, garden land use, due to having high organic matter, could improve the soil quality. However, the pasture land use had the worst soil quality due to the weak cover and the low organic matter.
