Relationships between soil depth and terrain attributes in a semi arid hilly region in western Iran

Soil depth generally varies in mountainous regions in rather complex ways.Conventional soil survey methods for evaluating the soil depth in mountainous and hilly regions require a lot of time,effort and consequently relatively large budget to perform.This study was conducted to explore the relationships between soil depth and topographic attributes in a hilly region in western Iran.For this,one hundred sampling points were selected using randomly stratified methodology,and considering all geomorphic surfaces including summit,shoulder,backslope,footslope and toeslope;and soil depth was actually measured.Eleven primary and secondary topographic attributes were derived from the digital elevation model(DEM) at the study area.The result of multiple linear regression indicated that slope,wetness index,catchment area and sediment transport index,which were included in the model,could explain about 76 % of total variability in soil depth at the selected site.This proposed approach may be applicable to other hilly regions in the semi-arid areas at a larger scale.     

Preparation,Characterization of a Novel Chelating Resin Functionalized with o‐Hydroxybenzamide and Its Application for Preconcentration of Trace Metal Ions

A stable extractor of metal ions was synthesized through azo linking of o‐hydroxybenzamide (HBAM) with Amberlite XAD‐4 (AXAD‐4) and was characterized by elemental analyses, IR spectral, and thermal studies. Its water regain value and hydrogen ion capacity were found to be 12.93 and 7.68 mmol g^?1, respectively. The optimum pH range (with the half‐loading time [min], t_1/2) for Cu(II), Cr(III), Ni(II), Co(II), Zn(II), and Pb(II) ions were 2.0–4.0 (5.5), 2.0–4.0 (7.0), 2.0–4.0 (8.0), 4.0–6.0 (9.0), 4.0–6.0 (12.0), and 2.0–4.0 (15.0), respectively. Comparison of breakthrough and overall capacities of the metals ascertains the high degree of column utilization (>70%). The overall sorption capacities for Cu(II), Cr(III), Ni(II), Co(II), Zn(II), and Pb(II) ions were found to be 0.29, 0.22, 0.20, 0.16, 0.13, and 0.11 mmol g^?1 with the corresponding preconcentration factor of 400, 380, 380, 360, 320, and 320, respectively. The limit of preconcentration was in the range of 5.0–6.3 ng mL^?1. The detection limit for Cu(II), Cr(III), Ni(II), Co(II), Zn(II), and Pb(II) were found to be 0.39, 0.49, 0.42, 0.59, 0.71, and 1.10 ng mL^?1, respectively. The AXAD‐4‐HBAM has been successfully applied for the analysis of natural water, multivitamin formulation, infant milk substitute, hydrogenated oil, urine, and fish.     

Prediction of effective porosity from seismic attributes using locally linear model tree algorithm

In this study, a locally linear model tree algorithm was used to optimize a neuro‐fuzzy model for prediction of effective porosity from seismic attributes in one of Iranian oil fields located southwest of Iran. Valid identification of effective porosity distribution in fractured carbonate reservoirs is extremely essential for reservoir characterization. These high‐accuracy predictions facilitate efficient exploration and management of oil and gas resources. The multi‐attribute stepwise linear regression method was used to select five out of 26 seismic attributes one by one. These attributes introduced into the neuro‐fuzzy model to predict effective porosity. The neuro‐fuzzy model with seven locally linear models resulted in the lowest validation error. Moreover, a blind test was carried out at the location of two wells that were used neither in training nor validation. The results obtained from the validation and blind test of the model confirmed the ability of the proposed algorithm in predicting the effective porosity. In the end, the performance of this neuro‐fuzzy model was compared with two regular neural networks of a multi‐layer perceptron and a radial basis function, and the results show that a locally linear neuro‐fuzzy model trained by a locally linear model tree algorithm resulted in more accurate porosity prediction than standard neural networks, particularly in the case where irregularities increase in the data set. The production data have been also used to verify the reliability of the porosity model. The porosity sections through the two wells demonstrate that the porosity model conforms to the production rate of wells. Comparison of the locally linear neuro‐fuzzy model performance on different wells indicates that there is a distinct discrepancy in the performance of this model compared with the other techniques. This discrepancy in the performance is a function of the correlation between the model inputs and output. In the case where the strength of the relationship between seismic attributes and effective porosity decreases, the neuro‐fuzzy model results in more accurate prediction than regular neural networks, whereas the neuro‐fuzzy model has a close performance to neural networks if there is a strong relationship between seismic attributes and effective porosity. The effective porosity map, presented as the output of the method, shows a high‐porosity area in the centre of zone 2 of the Ilam reservoir. Furthermore, there is an extensive high‐porosity area in zone 4 of Sarvak that extends from the centre to the east of the reservoir.     

Seismic performance improvement of Special Truss Moment Frames using damage and energy concepts

Nowadays, one of the most important methodologies to reduce the destructive effects of severe earthquakes on structures is the use of energy dissipation devices (EDDs). In this paper, a new configuration of special truss moment frame (STMF) systems including EDDs is theoretically proposed to improve their seismic performance. Such an improvement is achieved by provision of bending performance in these frames. For this purpose, the devices called buckling resistant braces (BRBs) are located at the side of beam‐column connections as the top and bottom members of truss‐girders. In this context, a five‐bay nine‐story STMF is designed using the damage and energy concepts recently proposed in the literature. To show the effectiveness of the proposed system with respect to the similar recently presented STMFs, this frame is then subjected to non‐linear static and non‐linear time‐history analyses under several ground motion records in order to survey on its seismic performance. Subsequently, such engineering demand parameters as lateral displacement, inter‐story drift ratio, overturning moment and shearing forces of stories, residual deformations and maximum time‐history displacement at roof level, as well as the process of plastic hinges formation are investigated. The results show the effectiveness of proposed configuration of EDDs used to improve the seismic safety of STMFs. Copyright © 2014 John Wiley & Sons, Ltd.     

INTERPRETATION OF COPPER AND ZINC CONTAMINATION IN THE AQUATIC ENVIRONMENT OF PENINSULAR MALAYSIA WITH SPECIAL REFERENCE TO A POLLUTED RIVER, SEPANG RIVER

Three different aquatic ecosystems(an urban pond,Kelana Jaya Pond;a polluted river,Sepang River;and the intertidal and offshore areas of the west coast of Peninsular Malaysia)with different sets of ecological backgrounds and human activities were reviewed and assessed for the levels of Cu and Zn contamination with special reference to those found in polluted sediments collected from the Sepang River.The discussion on the contamination levels of Cu and Zn in the aquatic environment of Peninsular Malaysia was based on a comparison of the metal contamination of 4 kinds of aquatic environments.The comparison of 4 different areas was based on ① total concentrations of 2 metals;② the concentrations and percentages of the nonresistant(EFLE,acid-reducible and oxidisable-organic)and resistant geochemical fractions;and ③ correlation coefficients(R-values)based on data of 4 areas separately and a combination of 4 areas.The Sepang River recorded nonresistant fractions of 63.1% for Zn and 55.8% for Cu in addition to slightly lower metal concentrations when compared to those(60%-70%)reported before the shutting down of the piggery activities in that area.These nonresistant metal percentages(55%-63%)indicated that the metal concentrations were still dominated by anthropogenic sources since nonresistant fraction of metals were mostly contributed by anthropogenic sources.The positive results from the four different aquatic environments assessed here provided strong evidence to show that Malaysia's aquatic environment had received anthropogenic Cu and Zn.The present study also showed that the percentage of the nonresistant fraction and the R-values based on correlation analysis of Cu and Zn could be used as indicators of Cu and Zn pollution in the Malaysian aquatic ecosystem.Based on the present data,the correlation coefficients(R-values)are potential indicators of EFLE Cu and acid-reducible Cu of the sediments.The use of R-values as indicators of metal pollution is suggested and it is applicable to other heavy metal data although it should be improved in future studies.     

Spatio-temporal variation of land surface temperature and temperature lapse rate over mountainous Kashmir Himalaya

In this study, Land Surface Temperature(LST) and its lapse rate over the mountainous Kashmir Himalaya was estimated using MODIS data and correlated with the observed in-situ air temperature(Tair) data. Comparison between the MODIS LST and Tair showed a close agreement with the maximum error of the estimate ±1°C and the correlation coefficient 0.90. Analysis of the LST data from 2002-2012 showed an increasing trend at all the selected locations except at a site located in the southeastern part of Kashmir valley. Using the GTOPO30 DEM, MODIS LST data was used to estimate the actual temperature lapse rate(ATLR) along various transects across Kashmir Himalaya, which showed significant variations in space and time ranging from 0.3°C to 1.2°C per 100 m altitude change. This observation is at variance with the standard temperature lapse rate(STLR) of 0.65°C used universally in most of the hydrological and other land surface models. Snowmelt Runoff Model(SRM) was used to determine the efficacy of using the ATLR for simulating the stream flows in one of the glaciated and snow-covered watersheds in Kashmir. The use of ATLR in the SRM model improved the R2 between the observed and predicted streamflows from 0.92 to 0.97.It is hoped that the operational use of satellite-derived LST and ATLR shall improve the understanding and quantification of various processes related to climate, hydrology and ecosystem in the mountainous and data-scarce Himalaya where the use of temperature and ATLR are critical parameters for understanding various land surface and climate processes.     

Gravity Modeling of the Au–U Mineralized Crust at the North-Central Cameroon Illustrating Crustal Permeability

Natural Resources Research - The north-central Cameroon is located at the northern edge of Archean Congo–Sao Francisco craton and at the east of the West African craton. This area includes...