Calculation nitrogen and sodium budget from lysimeter-grown shortrotation willow coppice experiment

Alternative water resources utilization should take priority over the conventional irrigation water resources (surface and subsurface waters) in the future in Hungary as well, similarly to the global trends because of the climate change impacts. However because of the environmental risks (e.g. nitrate leaching and soil salinization) the reuse of the wastewater require sustainable practices hence the farmers and researchers are responsible for development soil management practices and irrigation principles. Aim of our study was to determine the impact of a wastewater originated from an African intensive catfish farm on the nitrogen budget of the soil-water-plant system in order to evaluate the nitrogen substitution effect and the risk of the nitrate leaching. On the other hand, the aim of the study was to calculate also sodium budget to assess the risk of the sodicity regard to the high sodium concentration of the wastewater. The experiment was conducted at the National Agricultural Research and Innovation Centre (NAIK), Research Institute of Irrigation and Water Management (OVKI) in Szarvas, Hungary. The experiment was set up in the NAIK ÖVKI Lysimeter Station in 2014 with energy willow. During the study (between 03.07.2015 and 21.04.2017) irrigation water quality, rainwater quality, willow N and Na uptake by stems and N and Na leaching was measured. Nitrogen and sodium budget were calculated for two years (2015, 2016) from these data. According to our results the wastewater had high nitrogen content what was able to increase the nitrogen amount in the examined budget however without supplementary fertilizer it could not able to balance the budget only just at W60 treatment (irrigation with wastewater: N concentration 22,7 mg/l). The wastewater had high environmental risk as soil sodicity according to results of the sodium budget

Használt termálvíz mezőgazdasági elhelyezésének (öntözés) hatása a talaj kicserélhető nátrium tartalmára és az összes oldott sótartalmára

Hazánkban a szélsőséges vízháztartási helyzetek fokozódásával a változó környezeti feltételekhez való alkalmazkodás megköveteli az aktuális mezőgazdasági gyakorlat módosítását az öntözés területén is. Az adaptáció egyik fontos eleme lehet az öntözéses gazdálkodási formák kiszélesítése, a víz- és energiatakarékos öntözési módok és módszerek előtérbe helyezése és nem utolsó sorban a használt vizek (szennyvizek, hulladékvizek, elfolyóvizek stb.), mint alternatív vízforrások öntözéses hasznosítása. Kísérletünkben egy intenzív afrikai harcsa-nevelő telepről származó használt termálvizet és Körös vizet használtunk fel energiafűz öntözésére egyéves liziméteres kísérletben. Az öntözéses kísérlet a Nemzeti Agrárkutatási és Innovációs Központ (NAIK) Öntözési és Vízgazdálkodási Önálló Kutatási Osztály (ÖVKI) szarvasi Liziméter Telepén valósult meg. A kísérletben 82-es fűz klón nyolcféle öntözéses kezelését alkalmaztuk. Eredményeink szerint a használt termálvíz minősége miatt öntözésre csak korlátozottan használható, mivel a szikesedésért leginkább felelős kémiai paraméterek (EC, SAR, nátriumszázalék és szódaegyenérték) értékei magasak. A vízminősége miatt (Körös víz felhasználásával) hígítással és gipsz javítóanyag hozzáadásával egy harmadik víztípust hoztunk létre (HG). A talaj kicserélhető kation tartalmában bekövetkező változásokat vizsgálva a használt termálvíz kiöntözése mellett a kicserélhető nátrium felhalmozódását mértünk valamennyi öntözési norma esetén. A hígított+kezelt öntözővíz (HG) mellett a talajban szignifikáns változás egy kicserélhető kation esetében sem történt. Körös víz öntözése mellett 15 és 30 mm öntözési norma esetén a hígított+kezelt vízhez hasonlóan jelentős változás nem történt, ugyanakkor a 60 mm-es öntözési norma mellett a nátriumtartalomban szignifikáns csökkenés volt kimutatható, amely a kilúgzásnak köszönhető. Az öntözetlen kezelésben a kicserélhető kalcium tartalom csökkenése mellett a magnéziumok mennyisége növekedett meg a talajkolloidok felületén, amely következtetésünk szerint természetes szikesedési folyamatok következménye. A talaj összes oldott sótartalma 0-40 cm mélységben a használt termálvizes öntözés után (60 mm öntözési norma) szignifikánsan különbözött a Körös vízzel öntözött kezelésekben mért értékektől, ugyanakkor a kezelt víz (HG) felhasználása mellett a talaj összes oldott sótartalma a Körös vízzel öntözött kezelésekben mért értékekhez hasonlóan változott és nem haladta meg a 0,05%-ot. A felhasznált öntözővizek talajra gyakorolt hatásának teljes körű értékeléséhez további talajvizsgálatokat tartunk szükségesnek, valamint a hosszú távú előrejelzések miatt a kísérletet folytatjuk több éven keresztül. Mindazonáltal megállapítható, hogy az elvégzett kísérletünk eddigi szakaszában az intenzív afrikai harcsanevelő telepről származó használt termálvíz jó minőségű vízzel való keverése és gipsz hozzáadása után felhasználható a talajvédelem szempontjából fenntartható módon, szolonyecesedés és sófelhalmozódás nélkül. | Because of the increasing frequency of extreme hydrological events in Hungary, conventional agricultural practices need to be modified in order to adapt to changing environmental factors. The development of new irrigation management practices, the use of water- and energy-saving methods and the reutilization of wastewater (agricultural effluents, treated wastewater, etc.) could be important elements in this adaptation. Used geothermal water (so called effluent water) from an intensive African catfish farm, water from the River Körös and improved effluent water were used in a lysimeter experiment for the irrigation of energy willow. The experiments were conducted at the Research Department of Irrigation and Water Management (OVKI) of the National Agricultural Research and Innovation Centre (NAIK) in Szarvas, Hungary. Seven irrigation treatments and one rain-fed control were applied in four replications during the 2015 vegetation period. The results demonstrated that the use of effluent water is limited by high values of the chemical properties responsible for sodification (EC, SAR, sodium content and bicarbonate toxicity,). For this reason, an improved form of effluent water produced by dilution and the addition of gypsum was also used for irrigation. Tests on changes in the exchangeable cation content of the soil showed that irrigation with effluent water led to the accumulation of exchangeable sodium at all the irrigation rates, while no significant changes were observed for any exchangeable cations in the case of diluted, treated effluent water. When water from the River Körös was used for irrigation no change in this parameter was recorded at irrigation rates of 15 or 30 mm, but the 60 mm irrigation rate resulted in a significant decline in the sodium content, associated with leaching. In the non-irrigated treatment a decrease in the exchangeable calcium content was accompanied by an increase in the quantity of magnesium on the surface of soil colloids, which could probably be attributed to natural sodification processes. After a year of irrigation with effluent water (at the 60 mm irrigation rate) the total dissolved salt content of the soil at a depth of 0-40 cm differed significantly from the values recorded in treatments given river water, but when the diluted, treated effluent water was applied, the total dissolved salt content in the soil was similar to that in the river water treatment and did not exceed 0.05%. Further soil analyses will be required to gain a better understanding of the effect of these irrigation sources on the soil, and the experiment will be continued for several years to give a long-term picture. It is clear from the present results, however, that effluent water from the intensive African catfish farm can safely be used for irrigation in a sustainable manner after mixing with good quality water and the addition of gypsum, without the danger of sodification or salt accumulation

Comparison of a new mass-concentration, chain-reaction model with the population-balance model for early- and late-stage aggregation of shattered graphene oxide nanoparticles

Aggregation as an essential mechanism impacting nanoparticle (NP) functionality, fate, and transport in the environment is currently modelled using population-balance equation (PBE) models which are computationally expensive when combined with other continuum-scale reactive transport models. We propose a new simple mass-concentration-based, chain-reaction modelling (CRM) framework to alleviate computational expenses of PBE and potentially to facilitate combination with other fate, transport, and reaction models. Model performance is compared with analytical PBE solution and a standard numerical PBE technique (fixed pivot, FP) by fitting against experimental data (i.e., hydrodynamic diameter and derived count rate of dynamic light scattering used as a representative of mass concentration) for early- and late-stage, aggregation of shattered graphene oxide (SGO) NP across a broad range of solution chemistries. In general, the CRM approach demonstrates a better match with the experimental data with a mean Nash-Sutcliffe model efficiency (NSE) coefficient of 0.345 than the FP model with a mean NSE of 0.29. Comparing model parameters (aggregation rate constant and fractal dimension) obtained from fitting CRM and FP to the experimental data, similar trends or ranges are obtained between the two approaches. Computationally, the modified CRM is an order-of-magnitude faster than the FP technique, suggesting that it can be a promising modelling framework for efficient and accurate modelling of NP aggregation. However, in the scope of this study, reaction rate coefficients of the CRM have been linked to collision frequencies based on simplified and empirical relationships which need improvement in future studies

Ion-specific particle aggregation probed by different analytical techniques

The present thesis focuses on particle aggregation in aqueous media, particularly on the role of different ions in solution. I present a rather wide view of this topic, starting with the well researched question of multivalent ions and the Schulze-Hardy rule, continuing with the less investigated effects different types of monovalent ions and the Hofmeister series, and finally addressing an entirely unexplored field, namely particle aggregation in water-miscible ionic liquids. This thesis describes a broad view of particle aggregation in different ionic media and presents a wealth of original results. Two among those should be particularly stressed. First, the presented comparison between light scattering and direct force measurements represents a novel approach to study particle aggregation phenomena. Second, the investigations involving ILs are innovative and will surely influence the rapidly evolving field of ILs in the near future. Therefore, the originality of this thesis is substantial

High CO₂ absorption by diamino protic ionic liquids using azolide anions

Highly efficient low-viscosity protic ionic liquids with enhanced CO2 absorption capacities exhibiting more than 20% w/w uptake.</p

Tuning Colloidal Stability of Layered Double Hydroxides: From Monovalent Ions to Polyelectrolytes

The growing number of applications of layered double hydroxide (LDH) colloids demands for detailed understanding of particle aggregation processes in such samples. Tuning the colloidal stability in aqueous suspensions is essential to design stable systems or to induce controlled aggregation of these elongated particles. In this review, recent progress in this field is summarized; in particular, the charging and aggregation of LDHs of various compositions and sizes in the presence of different aggregating agents are discussed. The review focuses on the effect of monovalent salts, multivalent ions, and polyelectrolytes on the suspension stability of LDHs. The provided information will help to better understand the origin of interparticle forces responsible for the colloidal stability and to design highly stable or aggregating LDH colloids according to the desired goals in certain applications. Moreover, potential future research directions to obtain a broader picture of LDH aggregation are also suggested