scholarly journals Properties and Constraints of Red-Yellow and Volcanic Ash Soils Planted to Rootcrops in the Philippines

2007 ◽  
Vol 07 (1) ◽  
pp. 52-78
Author(s):  
Anabella Tulin ◽  

Soil samples representing hightly weathered Red-Yellow and Volcanic Ash soils were collected from 45 pedons of different rootcrop producing provinces in the Philippines. This research was conducted to provide a comprehensive data on the properties and constraints of Red-yellow and Volcanic Ash soils planted to rootcrops through determination of the soils' various morphological, physical, and chemical properties. Some of the identified soil constraints associated with Red-Yellow and Volcanic Ash soils planted to rootcrops include : low organic matter, soil acidity, Al toxicity, low CEC, low amounts of exchangeable bases such as Ca, K, Mg, and Na, low P availability, high clay content, and highly compacted soils.

Author(s):  
O.S. Bezuglova ◽  

Rostov Region belongs to the highly protected natural territories characterized by the continuous plowing. There territories are the only reserves with the soils preserved in their natural state. However, these areas often lack detailed information about the soils quality and composition. Surveying soils on these territories is crucial for determination of their basic physical and chemical properties. The resulted compilation of soil maps could lay a foundation for creating the Red Book of Soils and the formation of a section in the soil-geographical database of the Russian Federation. Subsequently, such information can be used as a background data for the main types of soils in the region. It will be also valuable during monitoring and justification of conservation measures.


2015 ◽  
Vol 63 (1) ◽  
pp. 47-54 ◽  
Author(s):  
Karsten Schacht ◽  
Bernd Marschner

Abstract The use of treated wastewater (TWW) for agricultural irrigation becomes increasingly important in water stressed regions like the Middle East for substituting fresh water (FW) resources. Due to elevated salt concentrations and organic compounds in TWW this practice has potential adverse effects on soil quality, such as the reduction of hydraulic conductivity (HC) and soil aggregate stability (SAS). To assess the impact of TWW irrigation in comparison to FW irrigation on HC, in-situ infiltration measurements using mini disk infiltrometer were deployed in four different long-term experimental orchard test sites in Israel. Topsoil samples (0-10 cm) were collected for analyzing SAS and determination of selected soil chemical and physical characteristics. The mean HC values decreased at all TWW sites by 42.9% up to 50.8% compared to FW sites. The SAS was 11.3% to 32.4% lower at all TWW sites. Soil electrical conductivity (EC) and exchangeable sodium percentage (ESP) were generally higher at TWW sites. These results indicate the use of TWW for irrigation is a viable, but potentially deleterious option, as it influences soil physical and chemical properties.


2009 ◽  
Vol 97 (4-5) ◽  
Author(s):  
K. M. Dziewinska ◽  
A. M. Peters ◽  
J. A. La Verne ◽  
P. Martinez ◽  
J. J Dziewinski ◽  
...  

AbstractDensity measurements of plutonium metal and its alloys are performed at Los Alamos National Laboratory (LANL) using a technique based on the Archimedes principle. The goal is to find and characterize a fluid for density determination of large objects made of plutonium to replace the currently used monobromobenzene. Physical and chemical properties must be considered while selecting the fluid. Chemical properties of the fluid must ensure low corrosion rates and good resistance to radiological decomposition. The study was carried on to evaluate the corrosion rates of Pu metal cause by FC-43 and the FC-43 decomposition products of radiolysis. The results of these studies proved favourable for this application. The evaluation of the surface reactions between FC-43 and Pu metal will be conducted in the near future.


2014 ◽  
Vol 70 (a1) ◽  
pp. C141-C141
Author(s):  
Ozen Ozgen ◽  
Engin Kendi ◽  
Semra Koyunoglu ◽  
Akgul Yesilada ◽  
Hwo-Shuenn Sheu

A significant part of medicine is based on the discovery and development of drugs. It is very important to know the crystal structure of pharmaceutical compounds for fundamental understanding of structure, physical and chemical properties. Many of these materials are available only as powders. So any structural information must be obtained from powder diffraction. I am going to present following the stages while solving the structure of C23H19N4OBr, 2-[3-phenyl-4(m-bromophenyl)-2-pyrazolin-1-yl]-3-methyl-4(3H)-quinazolinone, from 2-pyrazolines derivatives. The compounds are known to display various biological properties such as fungicidal insecticidal, anti bacterial, anti viral activities, pharmacological properties such as antiinflammatory agents and have industral properties(1). The powder diffraction data was collected with Debye Scherrer camera at the BL01C2 beamline at room temperature in National Synchrotron Radiation Research Center(NSRRC), Taiwan. X-ray of wavelength was 1.0333Å. This compound crystallizes in orthorhombic system space group P bca, Z=8, unit cell parameters of a=25.83(1)Å, b=15.55(5)Å, c=10.63(3)Å, and V=4266.0(10)Å3. Reliability factors were reached Rwp=0.075, Rp=0.053, RB=0.086 ve S=1.31 after Rietveld refinement.


Clay Minerals ◽  
2009 ◽  
Vol 44 (1) ◽  
pp. 135-155 ◽  
Author(s):  
R. L. Parfitt

AbstractThe literature on the formation, structure and properties of allophane and imogolite is reviewed, with particular emphasis on the seminal contributions by Colin Farmer. Allophane and imogolite occur not only in volcanic-ash soils but also in other environments. The conditions required for the precipitation of allophane and imogolite are discussed. These include pH, availability of Al and Si, rainfall, leaching regime, and reactions with organic matter. Because of their excellent water storage and physical properties, allophanic soils can accumulate large amounts of biomass. In areas of high rainfall, these soils often occur under rain forest, and the soil organic matter derived from the forest biomass is stabilized by allophane and aluminium ions. Thus the turnover of soil organicmatter in allophanicsoils is slower than that in non-allophanicsoils. The organic matter appears to be derived from the microbial by-products of the plant material rather than from the plant material itself. The growth of young forests may be limited by nitrogen supply but growth of older forests tends to be P limited. Phosphorus is recycled through both inorganic and organic pathways, but it is also strongly sorbed by Al compounds including allophane. When crops are grown in allophanic soils, large amounts of labile P are required and, accordingly, these soils have to be managed to counteract the large P sorption capacity of allophane and other Al compounds, and to ensure an adequate supply of labile P. Because of their physical and chemical properties, allophanic soils are excellent filters of heavy metals and pathogens.


Author(s):  
Kaplaushenko Tm ◽  
Panasenko Oi ◽  
Kucheryavy Yu

ABSTRACTObjective: Fundamental research in pharmacy and medicine have shown that drugs, which are based on nucleus of the 1,2,4-triazole, have a widerange of biological effects. Derivatives of this heterocyclic system have well-known Ukrainian clinicians and the world scientists due to its antifungal,antidepressant, anticancer, cardio- and hepatoprotective properties. The pharmacological activity of most organic compounds depends on severaldifferent factors, including bioavailability of the substance. Hence, it is very important to consider the results of the synthetic and biological researchesand established dependence of structure on the biological action when scientists model new molecules or improve pharmacological properties of anexisting structure. One of the important social and economic problems of the pharmaceutical industry is the implementation in practice of new drugsthat could compete with expensive imported drugs. In recent times, 1,2,4-triazole-3-thioderivatives take attention of compatriots and scientists offoreign countries who are working on finding bioactive compounds including heterocyclic systems. The structure, physical and chemical properties,pharmacological activities of 1,2,4-triazoles, and their 3-thioderivatives are understudied. Hence, the study of that will be actually and novelty formodern science. The main purpose of our research is synthesis of 3-alkylsulfonyl-5-(chinoline-2-yl, 2-hydroxychinoline-4-yl)-4-R-2,4-dihydro-3N1,2,4-triazoles,studyingof its physicaland chemical properties.Methods: The initial compounds have been synthesized previously using known in literature techniques. Oxidation of the sulfur atom of thesynthesized compounds to the hexavalent condition was carried out adding solution of hydrogen peroxide.Results: The structure of the obtained compounds was determined with the modern physical and chemical analysis methods: Element analysis,infrared-spectrophotometry, and their individuality with thin layer chromatography.Conclusions: Prospect of the further researches is determination of acute toxicity and next studying of pharmacological properties of the synthesizedcompounds.Keywords: 1,2,4-triazoles, Synthesis, Chemical properties, Chinoline.1 


Sign in / Sign up

Export Citation Format

Share Document