Sustainable Treatment of Aquaculture Effluents – What Can We Learn from the Past for the Future?

Many aquaculture systems generate high amounts of wastewater containing compounds such as suspended solids, total nitrogen and total phosphorus. Today, aquaculture is imperative because fish demand is increasing. However, the load of waste is directly proportional to the fish production. Therefore, it is necessary to develop more intensive fish culture with efficient systems for wastewater treatment. A number of physical, chemical and biological methods used in conventional wastewater treatment have been applied in aquaculture systems. Constructed wetlands technology is becoming more and more important in recirculating aquaculture systems (RAS) because wetlands have proven to be well-established and a cost-effective method for treating wastewater. This review gives an overview about possibilities to avoid the pollution of water resources; it focuses initially on the use of systems combining aquaculture and plants with a historical review of aquaculture and the treatment of its effluents. It discusses the present state, taking into account the load of pollutants in wastewater such as nitrates and phosphates, and finishes with recommendations to prevent or at least reduce the pollution of water resources in the future.DAA

Modification, Transport, and Sources of Hydrocarbon Oxidation Products from Groundwater at Crude Oil and Diesel Spill Sites in Minnesota: Unveiling Common “ThEEMs” via Spectroscopy & Chromatography

In this thesis, petroleum-contaminated groundwater from three spill-affected Minnesota sites—two contaminated with crude oil; one with diesel—is investigated to elucidate whether differences in degradation products from different parent oils exist. After spill events, parent molecules from the leaked oil seep underground and undergo microbial degradation over time, transforming into hydrocarbon oxidation products (HOPs), water-soluble contaminants that infiltrate groundwater aquifers, flowing into nearby environments and towns while exhibiting environmental persistence, toxicity to aquatic biota, and potential risks to humans that become exposed. Spectroscopic and chromatographic study of the structural themes and spatial distributions of HOPs reveals preferential degradation of aliphatic (biolabile) over condensed aromatic (biorefractory) HOPs, with distinct diesel trends detected. Thus, correlations between crude oil- and diesel-based degradational products and the parent petroleum at spill sources were exposed at the three contaminated groundwater sites, offering insight for environmental risk assessment and mitigation strategies to better predict spill outcomes

Exposure of Common Bean Seeds to Liquid Nitrogen Modifies Mineral Composition of Young Plantlet Leaves

Many publications describe cryopreservation techniques but only a few studies have focused on the biochemical and physiological changes occurring in plants regenerated from seeds exposed to liquid nitrogen. This paper aims at describing the effect of common bean seed cryostorage on mineral nutrition of young plantlets. The following elements were measured on leaves of 10-day-old plantlets from non-cryopreserved and cryopreserved seeds: Al, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, S, Se, Sr and Zn. At 10 days after sowing, both treatments (control and cryopreserved seeds) showed 100% seed germination without any visual phenotypic difference. However, contents of several elements in the leaves were different. Exposure of seeds to liquid nitrogen decreased Cu, Cd and Na uptake and increased absorption of B and Al. Further studies are required to understand the mechanisms underlying the relationship between seed exposure to liquid nitrogen and mineral nutrition during the early stages of plantlet growth.DAADLeibniz University of HannoverUniversity of Ciego de Avila, Cub

Potassium, an important element to improve water use efficiency and growth parameters in quinoa (Chenopodium quinoa) under saline conditions

Due to changes in the ecosystem and misuse of resources, salinity also increases. Approximately 20% of all irrigated land is affected by salinity and this will increase over time. Therefore, it is necessary to develop more environmentally friendly agricultural techniques but also to exploit potential crops with high nutritional value and tolerance to salinity like quinoa (Chenopodium quinoa Willd.). In this context, potassium is an essential macronutrient for plant growth and development. Furthermore, one of the strategies of some salt-tolerant plants is to increase the uptake of potassium under saline conditions such that the K+/Na+ ratio is maintained for a proper osmotic regulation in cells. Therefore, a study was conducted to investigate the effect of different concentrations of potassium (0.5, 2 and 6 mM K) on quinoa under different salinities (0, 100 and 200 mM NaCl). According to the results, an adequate supply of potassium under moderate salinity conditions benefited the plant growth, with a higher potassium uptake in the presence of salt. Under saline conditions, plant transpiration decreased significantly with a high correlation with stomatal density and a greater water use efficiency. Therefore, under saline conditions, adequate doses of potassium are highly recommended in quinoa cultivation. © 2021 The Authors. Journal of Agronomy and Crop Science published by Wiley-VCH GmbH

Halophyte plants and their residues as feedstock for biogas production—chances and challenges

The importance of green technologies is steadily growing. Salt-tolerant plants have been proposed as energy crops for cultivation on saline lands. Halophytes such as Salicornia europaea, Tripolium pannonicum, Crithmum maritimum and Chenopodium quinoa, among many other species, can be cultivated in saline lands, in coastal areas or for treating saline wastewater, and the biomass might be used for biogas production as an integrated process of biorefining. However, halophytes have different salt tolerance mechanisms, including compartmentalization of salt in the vacuole, leading to an increase of sodium in the plant tissues. The sodium content of halophytes may have an adverse effect on the anaerobic digestion process, which needs adjustments to achieve stable and efficient conversion of the halophytes into biogas. This review gives an overview of the specificities of halophytes that needs to be accounted for using their biomass as feedstocks for biogas plants in order to expand renewable energy production. First, the different physiological mechanisms of hal-ophytes to grow under saline conditions are described, which lead to the characteristic composition of the halophyte biomass, which may influence the biogas production. Next, possible mechanisms to avoid negative effects on the anaerobic digestion process are described, with an overview of full-scale applications. Taking all these aspects into account, halophyte plants have a great potential for biogas and methane production with yields similar to those produced by other energy crops and the simultaneous benefit of utilization of saline soils

Compositional Changes in Hydroponically Cultivated Salicornia europaea at Different Growth Stages

Abiotic stress conditions, such as salinity, affect plant development and productivity and threaten the sustainability of agricultural production. Salt has been proven to accumulate in soil and water over time as a result of various anthropogenic activities and climatic changes. Species of the genus Salicornia thrive in the most saline environments and have a wide climatic tolerance. They can be found in a variety of subtropical, oceanic, and continental environments. This study aims to establish Salicornia europaea as a novel source of plant-based compounds that can grow in areas unsuitable for other crops. The morphological and compositional changes in the tissues of S. europaea in different consecutive developmental stages have not been investigated so far. Therefore, a comprehensive study of changes during the lifecycle of S. europaea was carried out, following changes in the plant’s composition, including biomass yield, and soluble and insoluble compounds. For this, plants were cultivated in hydroponics for 15 weeks and harvested weekly to analyze biomass production, to determine soluble and insoluble compounds, protein content, and polyphenols. According to the results, glucan, xylan, and lignin increase with plant age, while water extractives decrease. Protein content is higher in young plants, while flavonoid content depends on the phenological stage, decreasing in the early flowering stage and then increasing as plants enter early senescence. Our results can aid in finding the optimal harvesting stage of S. europaea, depending on the component of interest

Screening of emerging pollutants (Eps) in estuarine water and phytoremediation capacity of tripolium pannonicum under controlled conditions

The increasing number of pharmaceuticals in the environment and their difficult biodegra-dation, can lead to bioaccumulation in different trophic compartments. Their bioaccumulation can have negative consequences, especially in the generation of bacterial resistance by antibiotics, but also in the impairment of plant and animal metabolism. The Tejo estuary in Portugal is the habitat for many plant and animal species, which are also prone to this type of contamination. There-fore, in the present study different classes of emerging pollutants (EPs) were surveyed in water samples in the Tejo estuary, including antibiotics, anticonvulsants, antidepressants, lipid-lowering drugs, anti-inflammatory drugs, beta-blockers and analgesics. According to the results, only four compounds were detected in water samples collected at the three selected salt marshes, including carbamazepine, fluoxetine hydrochloride, venlafaxine hydrochloride and acetaminophen. Having the detected substances as a basis, a subsequent study was performed aiming to investigate the uptake and biodegradation capacity of halophytes, using Tripolium pannonicum as a model plant culti-vated under controlled conditions with different concentrations of the found EPs. This experimental approach showed that T. pannonicum was able to uptake and degrade xenobiotics. Moreover, the application of sulfamethazine, as a model antibiotic, showed also that this species can uptake and degrade this compound, although the degradation rate and process proved to be compound-specific. This was also confirmed using crude plant extracts spiked with the different EPs. Thus this species is a potential candidate for the remediation of marine water and sediments contaminated with environmentally-significant EPs. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Halophytes as Feedstock for Biogas Production: Composition Analysis and Biomethane Potential of Salicornia spp. Plant Material from Hydroponic and Seawater Irrigation Systems

The halophyte plant species Salicornia europaea and Salicornia ramosissima were investigated for their potential to serve as a substrate for biogas production. Salicornia europaea was cultivated in hydroponic systems under varying salt concentrations (0, 10, 20, and 30 g/L NaCl), while S. ramosissima was grown in greenhouse farming with aquaculture effluent irrigation. The biomethane potential of the two halophyte feedstocks was determined through batch experiments, and correlations to the plant biochemical composition were investigated. Ash and mineral content of S. europaea was correlated to the increasing salt concentration used for plant cultivation in hydroponic systems. No indication of inhibition of the anaerobic digestion process was detected for sodium concentrations of up to 2400 mg/L in the anaerobic batch-test assays. The highest biomethane yield of S. europaea of 250 mL CH4/gVS was obtained when grown under 20 g/L NaCl and up to 300 mL CH4/gVS for S. ramosissima. By concentrating the dry matter content, the biomethane yield per ton of feedstock could be increased from 24 m3 CH4/t of the fresh halophyte plant to 74 m3 CH4/t by fractionation into a pulp fraction and to 149 m3 CH4/t by drying of the plant at room temperature for 1 week. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

NASA Human Exploration Rover Challenge

NASA\u27s Human Exploration Rover Challenge, held annually in at the Marshall Space Flight Center in Huntsville, Alabama, is an engineering design challenge that asks teams of student engineers to design a human-powered vehicle capable of traversing a simulated lunar surface. The rover must be able to be transported in a 5x5x5 foot cube, echoing the design constraint faced by the engineers who built the Lunar Roving Vehicles used by the astronauts of the later Apollo missions

Aumentando la productividad en una empresa panificadora

In a changing and competitive environment, companies must seek to increase the number of products withthe same resources, so this article has how to design different alternatives to increase productivity in the company "Charlotte Patisserie", first by carrying out a general investigation, then by doing data and analyzing them to culminate with the generation of the different improvement alternatives for the blueberry cheesecake star product, with the purpose of avoiding the interruption of work and optimizing the performance of the operators when collecting to prepare the desserts. The result obtained with the best alternative proposed was an increase in productivity of 12 % through the reduction of travel and operation times.   ILIA: Investigaciones Latinoamericanas en Ingeniería y Arquitectura, No. 01, 2024: 155-158.En un entorno cambiante y competitivo las empresas deben buscar incrementar la cantidad de productos con los mismos recursos; Por lo que el presente artículo tiene como objetivo diseñar diferentes alternativas para incrementar la productividad en la empresa “Charlotte Patisserie”, en primera instancia realizando una investigación general, luego recolectando datos y analizándolos para culminar con la generación de las diferentes alternativas de mejora para el producto estrella cheesecake de blueberry, con el propósito de evitar la interrupción de labores y optimizar el desempeño de los operarios al momento de elaborar los postres. El resultado obtenido con la mejor alternativa planteada fue un incremento de la productividad de un 12 % a través de la disminución de tiempos de recorrido y de operación.   ILIA: Investigaciones Latinoamericanas en Ingeniería y Arquitectura, No. 01, 2024: 155-158.