We compared the stable carbon isotopic composition (d13C) of crustacean zooplankton with that of potential carbon sources in 15 lakes in northern Sweden with different dissolved organic carbon (DOC) concentrations (2–9 mg L21) to test the hypothesis that zooplankton depended more on allochthonous carbon in humic lakes than in clear-water lakes. Based on d13C signature, we found that the pool of...

The greater Cairo area suffers from extreme levels of gas and particulate phase air pollutants. In order to reduce the levels of ambient pollution, the USAID and the Egyptian Environmental Affairs Agency (EEAA) have supported the Cairo Air Improvement Project (CAIP). As part of this project, two intensive ambient monitoring studies were carried out during the period of February 22 to March 4 an...

Most studies of freshwater dissolved organic matter (DOM) have been conducted in temperate climates where allochthonous organic material is abundant. Because climatic conditions of the Southwestern USA are different than temperate environments, DOM from three freshwater reservoirs (Saguaro Lake, Bartlett Lake and Lake Pleasant) was investigated to determine the importance of allochthonous and a...

A major fraction of fine particle matter consists of organic carbon (OC) but its origin is still inadequately known. In this study the sources of OC were investigated in the northern European urban environment in Helsinki, Finland. Measurements were carried out over one year and they included both filter (PM 1) and online methods. From 5 the filter samples OC, elemental carbon (EC), water-solub...

-The factors affecting the amounts and types of organic matter in lacustrine sediments are summarized in this review, and synthesis, of published studies. Biota hving in the lake and in its watershed are the sources of the organic compounds initially contributed to the lake system. Microbial reworking of these materials during sinking and early sedimentation markedly diminishes the total amount...

Our idea of Organic Oscillator is a combination of the mechanism of a table lookup oscillator and natural oscillation sources from audiences. Based on this idea, we conduct a series of audio and visual experiments, starting from using a single natural oscillation source in the human body to multiple ones from the audiences. Shifting from a singleparticipant paradigm to a group-participants para...

Semi-volatile and reactive primary organic aerosols are modeled on a global scale using the GISS GCM II' “unified” climate model. We employ the volatility basis set framework to simulate emissions, chemical reactions and phase partitioning of primary and secondary organic aerosol (POA and SOA). The model also incorporates the emissions and reactions of intermediate volatility organic compounds ...

the high cost of fertilizers in farming systems, soil pollution and degradation of soil are factors that caused to full use of available renewable nutrient sources of plant (organic and biological) with optimal application of fertilizers in order to maintain fertility, structure, biological activity, exchange capacity and water-holding capacity of the water in soil. therefore, in recent years, ...

This experiment was conducted to evaluate the bioavailability of different organic selenium (Se) products in finishing pigs. A total of 48 growing pigs, average body weight 47.6 kg±0.05, were allotted to four different treatments in a randomized complete block (RCB) design in three replicates with four pigs per pen. Three different organic Se products, Se-enriched yeast (treatments A and B) and...

Introduction: Organic compounds may survive beneath the surface or at the poles of the Moon. If so, at least a fraction of such compounds were probably delivered by asteroids and possibly comets. To the extent that inputs of carbon from different sources might vary as a function of geographic location and composition of crustal materials, future studies can advance our understanding of the orig...