The effects of plant density of Melastoma malabathricum on the erosion rate of slope soil at different slope orientations   总被引：2，自引：0，他引：2  

Aimee Halim  Osman Normaniza 《国际泥沙研究》2015,(2):131-141

Malaysia’s cut slopes,especially for road lines accommodation,are prone to erosions and landslides.These problems mainly occur due to lack of vegetation cover and strong erosive forces.In addition,the topography factors have also become a major factor affecting soil degradation.Thus,this study is aimed at determining the effects of planting density of a selected species,namely Melastoma malabathricum;one,two,and three seedlings per box,on the erosion rate at selected slopes of different orientation(morning and evening sun) at the Guthrie Corridor Expressway,Selangor.In six months of observation,treatment with three seedlings/box on the morning sun slope showed a lower erosion rate by 69.2%than those with the same treatment on the evening sun slope.In addition,the treatment of the three seedlings recorded at month six(final observation) had the highest reduction of soil saturation level(STL),by 23.6%.Furthermore,the physiological values of the species studied,grown on the morning sun slope,were higher in terms of stomatal conductance and photosynthetic rate by 12.1%and 15.8%(three seedlings/box),respectively.The overall results showed that plant density was inversely related to the STL and erosion rate on the slope.In conclusion,a planting density of three seedlings/box and morning sun orientation gave positive effects on the plant’s physiological performance of the slope,reducing the STL,as well as alleviating the erosion rate of slope soils.  相似文献   

A study of gross alpha and beta measurements for thermal springs in Central Anatolia,Turkey     

Mihriban Şahin  Mehmet Emin Korkmaz  Osman Agar  Abdullah Dirican 《Environmental Earth Sciences》2017,76(3):121

A screening of natural radioactivity content has been carried out in thermal water samples collected from surrounding of Central Anatolia, Turkey. The concentration levels of gross alpha and beta of 19 different samples has been determined using the low background gas-flow proportional counter. The measured gross alpha and beta activities in waters range from 0.11 to 16 Bq/L and 0.10 to 16.9 Bq/L, respectively. The measured values of gross alpha and beta concentrations are compared to previous studies in the literature and recommend WHO guideline activity concentration. The data resulting from the measurement have been statistically analyzed.  相似文献   

Development and application of a new drought severity index for categorizing drought-prone areas: a case study of undivided Andhra Pradesh state,India     

Kumar  P. Vijaya  Osman  Mohammed  Mishra  P. K. 《Natural Hazards》2019,97(2):793-812

Natural Hazards - The state of undivided Andhra Pradesh, India, spent around US$ 20 million per annum on drought relief programs during the period 1998–2008. However, till date, no long-term...  相似文献   

Third-order Uranus-Neptune theory by Hori's method     

Osman M. Kamel 《Earth, Moon, and Planets》1989,45(2):127-137

We construct a U-N secular canonical planetary theory of the third order with respect to planetary masses. The Hori-Lie procedure is adopted to solve the problem. Expansions have been carried out by hand, neglecting powers higher than the second with respect to the eccentricity-inclination. We take into account the principal as well as the indirect part of the planetary disturbing function. The theory is expressed in terms of the Poincaré canonical variables, referring to the Jacobi-Radau set of origins. We assume that the 1:2 U-N critical terms and its multiples are the only periodic terms.  相似文献   

Second order secular planetary theory for the four major planets     

Osman M. Kamel  Abdel Aziz Bakry 《Earth, Moon, and Planets》1984,31(2):123-134

We generalize our results of a second order Jupiter-Saturn planetary theory to be applicable for the case of the four major planets.We use the Von Zeipel method and we neglect powers higher than the third with respect to the eccentricities and sines of the inclinations in our expansions. We consider the critical terms as the only periodic terms.  相似文献   

Sustainable development and international cooperation in the Eastern Nile Basin     

Salah El-Din Amer  Yacob Arsano  Atta El-Battahani  Osman El-Tom Hamad  Magdy Abd El-Moenim Hefny  Imeru Tamrat  Simon A. Mason 《Aquatic Sciences - Research Across Boundaries》2005,67(1):3-14

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Determination of undrained strength of fine-grained soils by means of SPT and its application in Turkey   总被引：1，自引：0，他引：1  

O. Sivrikaya  E. To?rol 《Engineering Geology》2006,86(1):52-69

The Standard Penetration Test (SPT) is one of the oldest and the most common in situ test used in soil explorations. In the recent years with the advent of new technology and techniques in determining the drawbacks in SPT, several researchers have attempted to correlate corrected field measured values with several soil properties. In this context, corrections applied to field values have become critical. In this study a questionnaire including the performance of the standard penetration test and equipment used in practice in Turkey is circulated in order to determine the relevant correction factors. Thus the appropriate corrections are used in acquiring corrected SPT-N values. The relationships between SPT-N and the undrained shear strength (S_u) are examined from the statistical point of view by taking the test types and SPT corrections into consideration, and comparison is made with previous studies. It is observed that SPT corrections play an important role on the obtained correlation equations. In addition, the importance of the effects of test types on the correlations is also emphasized. The Standard Penetration Test is found to be sufficient for reliable assessment of S_u.  相似文献   

Fourier techniques for an analysis of eclipsing binary light curves. V     

Osman Demircan 《Astrophysics and Space Science》1980,67(2):367-374

An integral transform called the momentsA _2m of the light curves has been introduced by Kopal (1975) and utilized in the subsequent papers for an analysis of the light curves of eclipsing variables. The aim of the present paper is to generalize this integral transform by two distinct ways: (i) by introducing an exponential factor, and (ii) a Jacobi polynomial as multiplicative factor into the integrand of the transformA _2m. Observational values of these general transforms are likewise obtainable. They have been expressed in terms of eclipse elementsr _1,2,i andL ₁. These expressions can be used to solve the eclipse elements in terms of observed quantities. Free parameters in the expressions increase the flexibility in applications and may be utilized to improve the determinacy of the elements.  相似文献   

The evaluation of certain integrals encountered in the Fourier analysis of light curves of eclipsing variables     

Demircan  Osman 《Astrophysics and Space Science》1978,53(1):257-260

Astrophysics and Space Science -  相似文献   

The active Kalabsha Fault Zone in Southern Egypt: detecting faulting activity using field-structural data and EMR-technique,and implications for seismic hazard assessment     

Z. Hamimi  W. Hagag  R. Osman  M. El-Bialy  I. Abu El-Nadr  M. Fadel 《Arabian Journal of Geosciences》2018,11(15):421

Since November 14, 1981 earthquake (ML 5.6), about 60 km southwest of Aswan High Dam, the seismic hazard raised and the Aswan Local Seismic Network (ALSN) has recorded and precisely monitored the seismic activity in the vicinity of the High Dam. The major source of seismic activity in this region is the active Kalabsha Fault Zone (KFZ). The focal mechanism solutions indicate that two nodal planes strike E to ENE, with subordinate right-lateral strike-slip component and N to NNW, with left-lateral movement. The directions of tectonic extension (T) and compression (P) are NNE-SSW and NNW-SSE, respectively. Structural investigations and application of the Electromagnetic Radiation (EMR) technique reveal ongoing activity on the KFZ. Kinematic evolution of the KFZ implies faulting events with a strong movement intervened with periods of severe crushing, grinding, and even pulverization. Such tectonic processes have resulted in fault-breccia and fault-gouge. Results obtained from the present study indicate that the KFZ is not a single transcurrent wrench fault with dextral sense of movement but, instead, it represents a major dextral transtensional shear or fault zone deforming southern Egypt and plays a significant role in the structural shaping of the area to the west of Nasser Lake. Furthermore, the activity on the KFZ is most probably controlling the seismic cycle in the area. Topographic expression of KFZ is evidently realized at Sinn El-Kaddab scarp, as well as at Gebel Marawa. Frequent surface rupturing and newly recorded strong seismic activity advocate faulting reactivation supported by the EMR data, which suggest an active fault system oriented ENE-WSW and NNW-SSE affecting the KFZ, with a maximum horizontal stress (σ1) perturbing between ENE and NNW directions.  相似文献