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Este artigo tem como tema a adoção de soluções baseadas na natureza (SbN) na drenagem de águas pluviais em cidades da América Latina, considerando que as SbN prestam serviços ambientais e contribuem para tornar as cidades mais resilientes. Pondera que, como evidenciado pelo confronto entre a realidade do setor e o desejável para sua adoção, existem questões a enfrentar tais como a falta de visão sistêmica na estrutura governamental e a inadequação do arranjo institucional responsável pelo setor. Objetivando aprofundar a reflexão sobre a adoção de SbN, em especial do ponto de vista da ação governamental em bacias “metropolizadas”, adota-se São Paulo e Cidade do México como estudos de caso. Tal reflexão apoia-se na revisão bibliográfica sobre aspectos conceituais e sobre a difusão e assimilação do tema na América Latina, bem como no exame de documentos relacionados à adoção de SbN na drenagem urbana e na adaptação a eventos extremos nas áreas de estudo. Como resultado, além da identificação dos desafios locais, a pesquisa indica como oportunidade aberta a existência do Comitê de Bacia Hidrográfica Alto Tietê e do Consejo de Cuenca del Valle de México, os quais podem incorporar o tema de modo mais incisivo em sua pauta. Aponta ainda que aproveitar esta oportunidade trará ganhos ao processo: por um lado, pode-se valer da experiência destes arranjos com processos participativos e, por outro, com a adoção de processos de cocriação, pode-se aprimorar os procedimentos destes colegiados e, por extensão, a governança. Contudo, o cenário, embora favorável, ainda está sendo delineado.

Ascorbate (Asc, vitamin C) is an essential metabolite participating in multiple physiological processes of plants, including environmental stress management and development. In this study, we acquired knowledge on the role of Asc in dark-induced leaf senescence using Arabidopsis thaliana as a model organism. One of the earliest effects of prolonged darkness is the inactivation of oxygen-evolving complexes (OEC) as demonstrated here by fast chlorophyll a fluorescence and thermoluminescence measurements. We found that inactivation of OEC due to prolonged darkness was attenuated in the Asc-deficient vtc2-4 mutant. On the other hand, the severe photosynthetic phenotype of a psbo1 knockout mutant, lacking the major extrinsic OEC subunit PSBO1, was further aggravated upon a 24-h dark treatment. The psbr mutant, devoid of the PSBR subunit of OEC, performed only slightly disturbed photosynthetic activity under normal growth conditions, whereas it showed a strongly diminished B thermoluminescence band upon dark treatment. We have also generated a double psbo1 vtc2 mutant, and it showed a slightly milder photosynthetic phenotype than the single psbo1 mutant. Our results, therefore, suggest that Asc leads to the inactivation of OEC in prolonged darkness by over-reducing the Mn-complex that is probably enabled by a dark-induced dissociation of the extrinsic OEC subunits. Our study is an example that Asc may negatively affect certain cellular processes and thus its concentration and localization need to be highly controlled.

Photobiological hydrogen (H2) production is a promising renewable energy source. HydA hydrogenases of green algae are efficient but O2-sensitive and compete for electrons with CO2-fixation. Recently, we established a photoautotrophic H2 production system based on anaerobic induction, where the Calvin-Benson cycle is inactive and O2 scavenged by an absorbent. Here, we employed thin layer cultures, resulting in a three-fold increase in H2 production relative to bulk CC-124 cultures (50 µg chlorophyll/ml, 350 µmol photons m−2 s−1). Productivity was maintained when increasing the light intensity to 1000 µmol photons m-2s−1 and the cell density to 150 µg chlorophyll/ml. Remarkably, the L159I-N230Y photosystem II mutant and the pgrl1 photosystem I cyclic electron transport mutant produced 50% more H2 than CC-124, while the pgr5 mutant generated 250% more (1.2 ml H2/ml culture in six days). The photosynthetic apparatus of the pgr5 mutant and its in vitro HydA activity remained remarkably stable.

Chlamydomonas reinhardtii is a model organism of increasing biotechnological importance, yet, the evaluation of its life cycle processes and photosynthesis on a single-cell level is largely unresolved. To facilitate the study of the relationship between morphology and photochemistry, we established microfluidics in combination with chlorophyll a fluorescence induction measurements. We developed two types of microfluidic platforms for single-cell investigations: (i) The traps of the “Tulip” device are suitable for capturing and immobilizing single cells, enabling the assessment of their photosynthesis for several hours without binding to a solid support surface. Using this “Tulip” platform, we performed high-quality non-photochemical quenching measurements and confirmed our earlier results on bulk cultures that non-photochemical quenching is higher in ascorbate-deficient mutants (Crvtc2-1) than in the wild-type. (ii) The traps of the “Pot” device were designed for capturing single cells and allowing the growth of the daughter cells within the traps. Using our most performant “Pot” device, we could demonstrate that the FV/FM parameter, an indicator of photosynthetic efficiency, varies considerably during the cell cycle. Our microfluidic devices, therefore, represent versatile platforms for the simultaneous morphological and photosynthetic investigations of C. reinhardtii on a single-cell level.

Selenium (Se) is a natural trace element, which shifts its action in a relatively narrow concentration range from nutritional role to toxicity. Although it has been well established that in plants chloroplasts are among the primary targets, the mechanism of toxicity on photosynthesis is not well understood. Here, we compared selenate and red-allotrope elemental selenium nanoparticles (red nanoSe) in in vitro tobacco cultures to investigate their effects on the structure and functions of the photosynthetic machinery. Selenate at 10 mg/L concentration retarded plant growth; it also led to a decreased chlorophyll content, accompanied with an increase in the carotenoid-to-chlorophyll ratio. Structural examinations of the photosynthetic machinery, using electron microscopy, small-angle neutron scattering and circular dichroism spectroscopy, revealed significant perturbation in the macro-organization of the pigment-protein complexes and sizeable shrinkage in the repeat distance of granum thylakoid membranes. As shown by chlorophyll a fluorescence transient measurements, these changes in the ultrastructure were associated with a significantly diminished photosystem II activity and a reduced performance of the photosynthetic electron transport, and an enhanced capability of non-photochemical quenching. These changes in the structure and function of the photosynthetic apparatus explain, at least in part, the retarded growth of plantlets in the presence of 10 mg/L selenate. In contrast, red nanoSe, even at 100 mg/L and selenate at 1 mg/L, exerted no negative effect on the growth of plantlets and affected only marginally the thylakoid membrane ultrastructure and the photosynthetic functions.

The broad presence of biogas plants – facilities using organic wastes and by-products to generate energy – now seems to warrant urgent attention to the land application of by-products (fermentation residues) from biogas plants. In Hungary, this activity can be carried out under statutory conditions, subject to official licensing. The protection provided by law is necessary because an adaptable and sustainable agriculture based on effects and interactions also requires such attention, since the most important natural resource of agriculture is soil, which, by nature, is a conditionally renewable natural resource [1] [2]. Protection of soil means primarily protection of quality: sustainable and adaptable agriculture contributes to retain the ecological functions of soil and its role in the ecosystem [3]. This publication analyses the possibilities and challenges of natural resource management by studying the agricultural use of fermentation residues from biogas plants. In order to be used in agriculture, fermentation residue should be classified according to its character and nutritional value, namely as harmless waste from non-agricultural sources. This substance may have the properties of slurry, and in certain cases it may be classified as a substance with characteristics of waste water/sewage sludge or sewage sludge compost. Main elements of the preparation of the soil protection plan: detailed laboratory tests of the fermentation residue according to standards and regulations; classification of the fermentation residue on the basis of the measured parameters and the field tests corresponding to the character of fermentation residue according to the relevant legislation. Soil protection plan is prepared by expert based on on-site investigation and laboratory reports. This is the basis of the licensing process. Land application of fermentation residues therefore requires expert analysis to ensure that the ecological functions of soil are not damaged. This, however, requires that the regulations governing the framework for the conditions of such application are carefully studied and interpreted.

In the summer of 2014 at the Maintenance Division of Paks Nuclear Power Plant Ltd. in Hungary there was an opportunity to take part in the preparatory work a new and innovative project for introduction. This is a charge-planner software support using the tests related the new fuel. The necessary calculations were completed and after obtaining the results the conclusion is that the actual 12 month operating period – the so-called campaign length – can be increased to 15 months, by using and shuffling the new fuel with higher enrichment, and by loading six fuel assemblies with gadolinium oxide into the unit. Conclusion is the new Gd-2_4.7 fuel initial expectations were met and managed to find a favorable average enrichment not only considering nuclear physics, but also economic, risk management, material structure and security points of view as well. Testing can be started in the summer of 2015, and the fuel can be loaded into Unit 3 for a test period of 365 days.

The burial mounds, living mounds, guarding and border mounds (group name is “kurgan”) have been under environmental protection in Hungary since 1996. Besides the fact that they are important elements from archeological point of view, in many cases they reserve valuable remaining parts of onetime steppes, and studying of their buried soils can provide new data to learn more about the ancient environment, flora and the soil-formation processes took place long ago. In this way it can be obtained information about the Holocene climate changes. Our research team had seized the opportunity to examine several kurgans located in the Great Hungarian Plain. Two of them – the Csípő- and Lyukas-mound – has been examined in precise details through the involvement of experts of various disciplines. Due to this cooperation we could extend our researches and knowledge on the biogenic genesis of paleosoils and paleoecology concerning our kurgan studies. Therefore we utilized biomorphic analysis besides pedological investigations. Though the differences in sampling methods were significant, but the existence of a buried, ancient, undisturbed soil profile can be stated. According to morphological description of soil that was done after the kurgan’s excavation and drillings, we conclude that both the modern and paleosoils of the kurgans belong to Chernozem type soils, formed under predominantly arid steppe vegetation. Due to this fact we assume that the ancient environment of both kurgans was similar in many points with the modern landscape. Hence instead of closed forest vegetation rather loess-steppe or semi-shaded steppe can be reconstructed as the former environment of the mounds, which was mosaicly surrounded by water and salt affected areas. These results demonstrate that in the Carpathian Basin the Holocene climate changes are characterized by rather evenness, and but not the previously assumed character changes.

University of Szeged, Faculty of Engineering carried out research on behalf of Tisza Volán Company (integrated in Centre for South Great Plain Transport Plc.) which takes great care of environmental protection and sustainable management. So the fundamental objective of this research is to analyse utilization possibilities of used vegetable oils (waste frying oils derived from food production, food preparation) as fuels mixed into diesel fuel. This paper summarized the application possibilities, limitations, environmental impacts and difficulties of waste frying oils as fuels. The research points out that all action of different sizes of companies and behaviour of member of society are welcomed and they contribute to sustainable use of environment. This paper helps to expand the knowledge about the utilization of waste frying oils as fuels.