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11.
Fractionation of soil phosphorus (P) can provide useful information for assessing the risk of soil P as the potential sources of eutrophication in aquatic systems. Little information exists on P forms in paddy soils of Isfahan Province in central Iran, where P fertilizers have been continuously applied for at least 45 years. The objectives of this study were to investigate concentrations and proportions of P forms in paddy soils and correlate the content of P forms with basic soil properties. Soil samples from three paddy sites were obtained, and soil P forms were determined by a modified Hedley fraction method. Results show that the total P concentrations ranged from 288 to 850 mg kg?1 and were enriched in site 1. In all sites, the rank order of P fractions was HCl-P (CARB-P)?>?residual-P (RES-P)?>?NaOH-P (Fe-Al-P)?>?KCl-P (EXCH-P), indicating that Ca compounds are the main soil components contributing to P retention in these calcareous paddy soils. The EXCH-P represented on average?<?1 % of the total P, while the Fe-Al-P ranged 3.3–18 %. The CARB-P showed considerable contribution (63.6–85.6 %) to the total P. The Pearson correlation matrix indicated that Fe-Al-P only was positively correlated with total P, but did not show any significant correlations with other soil geochemical properties. Calcium-bound P fraction was significantly correlated with the clay, silt, cation exchange capacity, and total P. 相似文献
12.
Sepahvand Somayeh Bahrami Mostafa Fallah Narges 《Environmental science and pollution research international》2022,29(5):6479-6490
Environmental Science and Pollution Research - Discharge of 2,4-dinitrotoluene (2,4-DNT) into the environment leads to a serious soil and water sources pollution problem, due to toxicity and... 相似文献
13.
Ghanbari F Amin Sharee F Monavari M Zaredar N 《Environmental monitoring and assessment》2012,184(3):1221-1230
Regarding various types of pollutant, waste management requires high attention. Environmental site selection study, prior
to landfill operation, and subsequently, monitoring and maintaining of the location, are of foremost points in landfill site
selection process. By means of these studies, it is possible to control the undesirable impacts caused by landfills. Study
ahead aims at examination of effectiveness of a new method called Monavari 95–2 in landfill site assessment. For this purpose,
two landfills Rasht and Andisheh, which are, respectively, located on humid and arid areas, were selected as case studies.
Then, the results obtained from both sites were compared with each other to find out the weaknesses and strengths of each
site. Compared with others similar methods, much more criteria (53 parameters) can be considered within this method, so the
results will be more calculable. According to this method, Rasht landfill (site H) is classified as unacceptable landfill
site i.e. there is an urgent need for a new suitable site for landfill, while Andishe Landfill (site D) is ranked as acceptable
landfill site but needs environmental management program to handle the existing weaknesses. 相似文献
14.
Ava Heidari Mahdi Kolahi Narges Behravesh Mona Ghorbanyon Fatemeh Ehsanmansh Nogol Hashemolhosini Fahimeh Zanganeh 《Journal of Material Cycles and Waste Management》2018,20(4):2041-2053
The present study aims to develop the Theory of Planned Behavior (TPB) to explain comprehensively the establishment of intention and behavior toward source separation of waste. The extended TPB involves the significant structures affecting the behavior along with the original variables of TPB model. Data were gathered from 420 students in Ferdowsi University, Iran, using questionnaires, and analyzed by cluster analysis, discriminant analysis and structural equation modelling techniques (SEM). The cluster analysis identified three distinct grouping according to TPB constructs, and it was validated by discriminant analysis. SEM results displays that motivation had the most important impact on intention, followed by moral obligation, perceived behavior control, subjective norm, situational factor and attitude. Fit statistic of the extended TPB model was good and had better explanatory power compared to the original TPB. It describes 81 and 57% of the variance for intention and behavior toward source separation waste, respectively. 相似文献
15.
Mohammad Hossein Keshavarz Narges Zohari Seyed Abolfazl Seyedsadjadi 《Journal of Loss Prevention in the Process Industries》2013,26(6):1452-1456
This study presents a new simple correlation between electric spark sensitivity of nitramines and their activation energies of thermolysis, which are important for safety measures in industrial processes. The new correlation can help to elucidate the mechanism of initiation of energetic materials by electric spark. It can be used to predict the magnitude of electric spark sensitivity of new nitramines, which is difficult to measure. The methodology assumes that electric spark sensitivity of a nitramine with general formula CaHbNcOd can be expressed as a function of its activation energy of thermal decomposition as well as optimized elemental composition and the contribution of specific molecular structural parameters. The new correlation has the root mean square and the average deviations of 1.37 and 1.09 J, respectively, for 21 nitramines with different molecular structures. The proposed new method is also tested for 16 nitramines so that there is no experimental data of electrostatic sensitivity for them. 相似文献