Carbonaceous DBPs (THMs and HAAs) formation on Cl2 and ClO2 treatment of aqueous soluble fractions of soil-derived natural organic matter

surface water dissolved organic matter feature substantial portion of terrestrial origin and serve as important precursor for toxic disinfection byproduct formation.In the present study, organic matter extracted from the composite...

Anomalies of continental precipitation associated with El Niño Southern Oscillation: the role of moisture contribution from oceanic and terrestrial sources

<p>The regional and global precipitation pattern is highly modulated by the influence of El Niño Southern Oscillation (ENSO), which is considered the most important mode of climate variability on the planet. In this study was investigated the asymmetry of the continental precipitation anomalies during El Niño and La Niña. To do it, a Lagrangian approach already validated was used to determine the proportion of the total Lagrangian precipitation that is of oceanic and terrestrial origin. During both, El Niño and La Niña, the Lagrangian precipitation in regions such as the northeast of South America, the east and west coast of North America, Europe, the south of West Africa, Southeast Asia, and Oceania is generally determined by the oceanic component of the precipitation, while that from terrestrial origin provides a major percentage of the average Lagrangian precipitation towards the interior of the continents. The role of the moisture contribution to precipitation from terrestrial and oceanic origin was evaluated in regions with statistically significant precipitation anomalies during El Niño and La Niña. Two-phase asymmetric behavior of the precipitation was found in regions such the northeast of South America, South Africa, the north of Mexico, and southeast of the United States, etc. principally for December-January-February and June-July-August. For some of these regions was also calculated the anomalies of the precipitation from other datasets to confirm the changes. Besides, for these regions was calculated the anomaly of the Lagrangian precipitation, which agrees in all the cases with the precipitation change. For these regions, it was determined which component of the Lagrangian precipitation, whether oceanic or terrestrial, controlled the precipitation anomalies. A schematic figure represents the extent of the most important seasonal oceanic and terrestrial sources for each subregion during El Niño and La Niña.</p>

POTENTIAL OF UTILIZATION OF ALLOCHTHONOUS INVERTEBRATES BY GAMMARUS KOREANUS UÉNO (AMPHIPODA)

In an isolating experiment on feeding only on arthropods of terrestrial origin, the potential of their consump-tion by amphipods from a fishless water-course is studied. The data obtained confirm the hypothesis that, on the basis of experiments on feeding exclusively on arthropods, it is possible to determine the maximum proportion of their biomass that selected consumers are able to utilize. The results of such works can be used to quantitative assessment of the level of possible losses of allochthonous matter and energy for the recipient communities of waterbodies due to feeding activity of consumers from their tributaries. Assessments of this kind may be relevant when deciding on the food availability for juvenile salmonids, inhabiting recipient waterbodies.

Chemical composition of the Moon's 'primary' crust – a clue at a terrestrial origin

<p>The Moon is one of the best characterized objects in space science, yet its origin still actively researched. Available orbital, geophysical, and geochemical information imposes clear restrictions on the origin and evolution of the Earth-Moon system (e.g., Canup 2008, 2012; Ćuk and Stewart 2012; Young et al. 2016). In regard to geochemical constraints, one of the most puzzling conundrums is posed by the similar isotopic fingerprints of the Earth and the Moon (e.g., Wiechert et al. 2001; Armytage et al. 2012; Zhang et al. 2012; Young et al. 2016; Schiller et al. 2018), together with the apparent lunar depletion in volatile elements (e.g., Ringwood and Kesson 1977; Wanke et al. 1977; Albarède et al. 2015; Taylor 2014). This apparent lunar volatile depletion is most notable in the low K content in comparison to U, a finding based on chemical analyses of samples collected from the lunar surface and lunar meteorites, and on spectroscopic observations of the lunar near-surface, despite both having been heavily processed in the past ~ 4.4 billion years.</p><p>In the past 4.4 billion years, space has been a harsh environment for our Moon, especially in the beginning, when the young Sun was still very active and the young Moon was continuously bombarded by meteorites of varying sizes. Solar wind and micro-meteoritic interactions with the lunar surface led to rapid and intensive processing of the lunar crust. Hence, the K/U depletion trend observable on today's lunar surface does not necessarily reflect a K/U ratio valid for the Moon in its entirety. We model the evolution of the abundances of the major elements over the past 4.3 to 4.4 billion years to derive the composition of the original lunar crust. Accounting for this processing, our model results show that the original crust is much less depleted in volatiles than the surface observable today, exhibiting a K/U ratio compatible with Earth and the other terrestrial planets, which strengthens the theory of a terrestrial origin for the Moon.</p>

Dissolved organic matter fate in coastal Mediterranean site: Toulon bay case - France

<p>Dissolved organic matter (DOM) is a complex continuum of molecular species and plays an important role in biogeochemical processes in the aquatic ecosystem, waters and sediments <span>(Aiken et al., 2011; Bolan et al., 2011; Burdige et al., 2004; Chen and Hur, 2015; Fu et al., 2006; Jiang et al., 2018; Stedmon et al., 2003)</span><span>. </span>Once settled into marine sediments, organic matter undergoes biogeochemical transformations (Chen and Hur, 2015). These biogeochemical conditions are dependent on different parameters such as redox condition and microbial activities controlling its dynamics. Studies on pore water organic matter (PW-OM) and extracted organic matter (EOM) give understanding on the fate of sedimentary organic matter. Several studies (Burdige, 2001; Burdige et al., 2004; Chen and Hur, 2015; Dang et al., 2014; Hur et al., 2014; Murphy et al., 2008; Stedmon et al., 2003; Stedmon and Bro, 2008) have used Excitation Emission Matrices of fluorescence coupled to PARAFAC and UV-Vis spectroscopy to characterize DOM among several technics. As it is rapid and gives information on the dynamics, the aromatic structure and even the degree of humification of DOM. Toulon bay is a semi-enclosed bay located in the N-W basin of the Mediterranean Sea and in the S-E of the French coast. This bay is exposed to numerous pollution sources. The origins of organic matter in the bay is the input of two urbanized rivers (Las and Eygoutier), aquaculture, treated sewage outlets and planktonic activities (Boge et al., 2006; Nicolau et al., 2012). Sediment cores and column seawaters were collected at four points in the bay in front of Las River. Each core was sliced within a 2cm resolution under inert atmosphere (N<sub>2</sub>). Then, pore water was retrieved and filtered (0.2 µm) and solid fraction was freeze-dried, 2mm sieved, crushed. DOC and nutrients concentrations in water samples and total carbon, organic carbon (POC) and total nitrogen were measured on solid. Extraction with alkaline solution was performed and extracted organic carbon and extracted nitrogen were measured. 3D fluorescence measurements were done for all samples from 200 to 800 nm for both excitation and emission. The results showed that the degradation of OM was more intense in front of Las River than outside of the bay. Pore water and extracted OM are influenced by fresh biomass input and the latter is strongly humified. Pore water OM in the superficial layers of sediments comes from autochthonous origin and less humified with a weak aromaticity. However, in deep layers, it shows a terrestrial origin, a regain of aromaticity and an important humic character based on HIX index. Moreover, it is controlled by the production and degradation of nutrients and POC. Extracted OM derives from terrestrial origin and is strongly humified based on HIX index. The state of FDOM in superficial sediments is different from the one in deep sediments because of the reducing environment. There is a contradiction of FDOM fate/behavior between the dissolved and solid phase in deep sediments because the production of FDOM isn’t from the POC pool.</p>

Software and hardware system of multi-frequency oblique sounding the ionosphere

Background. The ionosphere was and will be the main channel for the propagation of radio waves of various bands (from extremely low to super-high frequencies). A feature of this channel is the dependence of its parameters on the state of space weather. Space weather is formed primarily by processes on the Sun and by processes on Earth (to a lesser extent). High-energy processes of man-made origin can also make a certain contribution to the state of space weather. Means of oblique sounding (OS) have significant opportunities for research in the field of geospace radiophysics, study of the channel of propagation of radio waves and dynamic processes in the geospace. In this case, both own radio transmitting devices and a network of broadcasting stations can be used. With the help of OS, it is possible to cover significant regions of the globe (up to global ones), and thereby study the dynamic processes in the geospace over these regions. The purpose of this work is to briefly describe the multi-frequency multiple-path radio system of the OS ionosphere and to illustrate its performance using the example of studying dynamic processes in the geospace. Techniques and Methodology. A coherent multi-frequency multiple-path oblique sounding radio system of the ionosphere is described. It is intended for radiophysical monitoring of dynamic processes in the geospace caused by variations in space weather, the impact on the ionosphere of high-energy sources of space and terrestrial origin. The complex is capable of receiving radio signals in the low-frequency (LF) and high-frequency (HF) ranges. Original software has been developed, depending on the range of tasks to be solved. The number of radio paths and their orientation depend on the specifics of the tasks being solved. The operation of the complex is based on measurements of the Doppler shift of frequency and amplitude or phase and amplitude of the signal. The autoregressive algorithm provides a Doppler frequency resolution of up to 0.02 Hz and a time resolution of 1 min. After obtaining the time dependences of the Doppler spectra, phases and amplitudes for various radio propagation paths, further processing of the time series is performed. Results. At V. N. Karazin Kharkiv National University, a multi-frequency multi-path radio engineering complex for oblique sounding of the ionosphere has been developed and is operating, designed for radiophysical monitoring of dynamic processes in the geospace caused by variations in space weather, the impact on the ionosphere of high-energy sources of space and terrestrial origin. Conclusions. The successful functioning of the complex is demonstrated by the example of studying the dynamic processes in the geospace caused by the action of various sources of energy release.