Cadmium (Cd) is a metal that can negatively interfere with the metabolic systems of living beings. The objective of this work was to evaluate the capacity for cadmium removal in aqueous solutions by immobilized Chlorella sp. in calcium alginate beads. Beads without Chlorella sp. were used as a control. All the treatments were established in triplicate for 80 min, at four concentrations of cadmium (0, 20, 100 and 200 ppm), taking samples of aqueous solution every 10 min, to be read using atomic absorption equipment. The study determined that the treatment of alginate beads with immobilized Chlorella sp. removed 59.67% of cadmium at an initial concentration of 20 ppm, this being the best removal result.

Soil management has great potential to affect soil respiration. In this study, we investigated the effects of organic versus conventional soil management on soil respiration. We measured the main soil physical-chemical properties from conventional and organic managed soil in Ecuador. Soil respiration was determined using alkaline absorption according to Witkamp. Soil properties such as organic matter, nitrogen, and humidity, were comparable between conventional and organic soils in the present study, and in a further analysis there was no statically significant correlation with soil respiration. Therefore, even though organic farmers tend to apply more organic material to their fields, but this did not result in a significantly higher CO2 production in their soils in the present study.

Soil respiration is a significant indicator of soil microbial activity; global soil respiration and decomposition processes release yearly to the atmosphere a total of 220 billion tons of carbon dioxide. Therefore, studies on the whole- or one particular aspect of soil carbon cycle aiming at optimizing agricultural carbon dioxide emissions or improving carbon sequestration contribute to a sustainable agriculture practice. In this paper we present the effects of biofertilizer application (Bacillus megaterium, Bacillus circulans, and Pseudomonas putida) on soil respiration in chernozem soil. Experiments were performed at Látókép Experimental Station, belonging to the University of Debrecen, Hungary. Additionally, we compare our results with findings of prior studies related to commercial NPK fertilizer applications (in four doses: N60P45K45; N120P90K90; N180 P135K135; and N240P180K180), and two different cultivation methods (ploughed, loosened, RTK in rows, and RTK between rows); these investigations were conducted at the same experimental station. Our results indicate lower tendency for soil respiration, when biofertilizers are applied as compared to commercialNPK fertilizers, which enables to decrease CO2 emission in the environment.We also discuss a unit change indifferent alkali absorption-based methods (Oxitop and Witkamp) to facilitate comparability of recently acquired data with results of previous long-term fertilization experiments.

Ecuador has a great variety of climatic regions that potentiate biodiversity. The family Orchidaceae constitutes one of the most important of the country, having identified about 4032 species with a high degree of endemism, therefore the development and research of alternative methods of storage and conservation of species is a strategy of primary interest for researchers and for society in general. In cryopreservation, temperatures reach below -190°C in order to paralyze the chemical reactions and keep the plant material viable for long periods. The present research focuses on the development of protocols for cryopreservation of seeds, aimed at the preservation of biodiversity, focusing on the family Orchidaceae, for the subsequent generation of a seed bank. The assays were performed on seeds of Epidendrum quitensium, Sobralia rosea, and Epidendrum anderssonii. Two freezing rates were tested: rapid freezing at -196°C; and step freezing at -22°C, -60°C to 196°C, further analyzed four combinations from Dimethylsulfoxide DMSO, glycerol and sucrose (DMSO 1M; DMSO 1M + glycerol 1M; DMSO 1M + sucrose 1M; DMSO 1M + glycerol 0,5M + sucrose 0,5M). The best results were obtained both in rapid and stepped freezing without the use of cryo-protective substances, by introducing the seeds directly into liquid nitrogen. Species of the genus Epidendrum presented a more efficient response in comparison to Sobralia. The viability of the seeds was evaluated by the tetrazolium test.

We address sustainable energy issues via scrutinizing magnesium-air reserve batteries. Such energy storage systems can hold their energy indefinitely, releasing it on demand, in emergency situations. Main advantage of water-activated batteries is that their electrolyte is supplied by the environment, where they get deployed, hence, only light weight electrodes and battery frames should be transported, rather than the significantly heavier aqueous electrolyte. Recent literature in the field is reviewed. One merit of this account is that recently, battery storage has become an effective way to increase share of renewables in photovoltaic energy systems utilized in farming. While the specific energy of reserve batteries can be determined unequivocally, their energy density calculation needs a clear definition of the considered battery volume. Therefore, this paper proposes a new modality of evaluating specific energy and energy density of seawater-activated metal-air reserve batteries for prismatic and cylindrical geometries, respectively.