Екологично инженерство и опазване на околната среда

Jean-Yves Trosset, Sami Tliba, Ali El Ati, Hela Friha, Estelle Mogensen, Jawher Kahouli, Robin Lacombe, Ouerdia Arkoun, Sette Diop, Rodrigo Ledesma-Amaro, Islam Boussaada

Abstract: Abundance or scarcity of external nutrients is a metabolic trigger, especially for highly proliferative cells such as bacteria, yeasts, parasites or tumors. In presence of oxygen cells usually adopt efficient metabolism in order to maximize energy production yield in poor diet. If nutrient resource increases, a metabolic shift from efficient metabolism (respiration) to inefficient metabolism (fermentation) is reflecting a minimal cost principle of living systems to optimize fitness. This is known as the Crabtree/Warburg effect. Identifying a model that describes the population dynamics of cells and the input growth condition are the goals of this study. Proof of principle has been constructed using a battery of growth experiments on Crabtree-positive yeasts–Saccharomyces under various conditions of glucose in aerobic and micro-aerobic conditions. General cell growth model estimating metabolic shift has been constructed based on an Auto Regressive approach.

Keywords: Yeast; Population dynamics; Modeling; Identification

CONTRIBUTION OF MODELING FOR A BETTER UNDERSTANDING OF MICROBIAL ECOSYSTEMS

Jérôme Harmand

Abstract. This paper aims at presenting how a number of recent modeling approaches can be used for better understanding microbial ecosystems dynamics. In first part, an important question – the ability of certain ecosystems to exhibit overyielding – is investigated using a model-based approach. It is shown that classical competition theory cannot explain such phenomenon, thus invalidating a large class of classical mass-balance-based models, Rapaport et al., 2019. In second part, we show how new combinatorial approaches can be used to find the best combination of species of a functional ecosystem with limited complexity. More precisely classification approaches inpired from the work by Jaillard et al., 2018 are used and illustrated with simulations. Their robustness with respect to a number of experimental parameters (investigated in simulation) is studied. For ecosystems with higher richness, we show how another probablilistic approach proposed by Jaillard et al., 2014 may be useful.

Keywords: Modeling, microbial ecosystems, microbial interactions, mathematical ecology, diversity, community assemblage.

ON THE EXTREMUM-SEEKING CONTROL DESIGN AND APPLICATION FOR ANAEROBIC DIGESTION PROCESSES

Maobo Hu, Haoping Wang, Yang Tian, Nicolai Christov and Ivan Simeonov

Abstract: The paper deals with the optimization of nonlinear systems by using Extremum Seeking Control (ESC) without any prior knowledge of the system model. An Extend Kalman Filter based Extremum Seeking Control (EKF based ESC) is proposed, which can make the amplitude of perturbation signal variable and ensure convergence to zero, i.e. without steady-state oscillation. The proposed ESC algorithm makes also possible to obtain more accurate gradient estimate and more rapid ESC convergence. The proposed EKF based ESC algorithm is applied to a fifth-order model of anaerobic digestion process and its performances are compared with the performances of the classical ESC algorithm.

Key Words: ESC, EKF, steady state oscillation, anaerobic digestion processes

ROBUST CONTROL AND STATE ESTIMATION OF A THREE-STAGE ANAEROBIC DIGESTION PROCESS

Samia Semcheddine, hanane bouchareb

abstract: The production of biogas via an anaerobic fermentation process is very interesting for various reasons: it not only produces renewable energy, but also facilitates the disposal of organic waste, therefore it preserves the environment, it contributes to the resolution of energy problems in agriculture and agro industry, it’s available for everyone because the waste is available everywhere. This process takes place in continuously stirred tank bioreactor and is described by a highly nonlinear model whose parameters are often uncertain thereby requiring robust control in any process performance enhancement procedure to optimize the biogas production. Thus a robust control technique, synergetic, is proposed to improve the settling time in a fermentation based biogas production in a simulation study; the simulation study is carried out on biotechnological process described by a five-order continuous-time reaction scheme described by three stages. An extended Luenberger observer is proposed under synergetic control to observe the different concentrations because of the high-cost and unavailable measurement instrumentation. The interest of paper lies in controlling the amount of bio methane produced and the observation of all the states of the system (5 different populations of the complex community of bacteria and substrate concentrations acting during anaerobic digestion (AD) processes) by simply measuring the biogas produced. The monitoring, controller and observer performance are evaluated via numerical simulations showing excellent responses under the influence of control input.

Key words: Bio methane, anaerobic digestion, synergetic control, extended Luenberger observer, state estimation.

REVOLUTIONARY CONCEPT OF GARBAGE HANDLING IN KOTA KUPANG, INDONESIA

Jefirstson Richset Riwukore, Fellyanus Habaora

ABSTRACT. The potential for garbage production will continue to increase along with the population growth rate and behavior patterns of human life. If not handled properly, it will have an impact on changes in negative benefits due to pollution from garbage. Kota Kupang is an area that has not been well managed about its garbage management. Therefore, scientific reviews are needed so that maximum changes occur in handling garbage in Kota Kupang. For this reason, research has been carried out using descriptive methods, then were analyzed qualitatively and quantitatively using secondary data. This research was conducted for two months (November-December 2018), and preparation of reports is carried out by stages of research, namely data collection, data reduction, data presentation, and conclusion drawing. The results of the research indicate that garbage management must be carried out changes of fundamental by considering to changes in household behavior in handling garbage, sustainability of the perspective on garbage as a useful material that starts from world of education, changes conventional methods of handling garbage in Cleaning and Living Environment Office of Kota Kupang, and a revolutionary perspective on garbage is needed, from useless materials to be useful materials for the economy.

Keywords: revolutionary concept, handling garbage, Kota Kupang

THE EDUCATIONAL PLATFORM OF CABARET PROJECT (WP7)

Boyko Ranguelov, Fathimath Shadiya, Fathimath Nistharan, Mariyam Humra, Mariyam Eeman, Mohamed Haikal Ibrahim

Abstract: The CABARET (Capacity Building in Asia for Resilience EducaTion) Project is funded by the European Union under the Erasmus+ program, to foster regional cooperation for more effective multi-hazard early warnings and increased disaster resilience among coastal communities. The goal of the Project is to strengthen the evidence-base in support of the implementation of the new framework. The participants constructed of a consortium of 14 European and Asian higher education institutions from nine countries - four from Europe and five from Asia. The Project covers three years period and intend many meetings among participants for data and knowledge exchange. The MGU (Mining and Geology University, Sofia, Bulgaria) and MNU (Maldives National University, Male, Maldives) participations are active as co-chairs of the WP7 – “Learning and teaching tools methodologies and approaches to the MHEW (Multi Hazards Early Warning Systems)” and sustainable development of the resilience. The progress and achievements of the WP7 co-chaired by MGU and MNU are presented and the developments of MOOC’s (Major Online Open Courses) are under discussion. The new concept about the Educational Platform (EP) targeted to the wider audience is proposed. In conclusion several topics are underlined:

- The international bilateral cooperation between MGU and MNU is established in the frame of the co-chairmanship of the WP7 – CABARET Project.

- Project is displayed including educational platform development and MOOC’s skeleton and schedule.

- First results of MOOC’s are available. Educational platform includes curriculum of Philippines for De La Sale University (DLSU) and Ateneo De Manila University (ADMU).

- New concept for the further development of the structure of the Educational Platform (EP) of the CABARET Projects is proposed. Intended international cooperation among participants of the Project is an essential topic for the coastal resilience educational platform development.

Keywords: Educational Platform, new concept, hazards, warnings.

DURANKULAK LAKE ACTUAL STATE AND MONITORING USING SENTINEL 2 SATELLITE DATA

Iva Ivanova, Iliyana Gigova, Temenuzhka Spassova, Nataliya Stankova

Abstract: Durankulak Lake is one of the most important wetlands in Bulgaria and Europe. It is included in the Ramsar Convention and it is recognized as an important bird area of world importance. The subject of protection within the protected zone is the condition of the natural habitats and the habitats of the species, including the natural species composition, the typical species and the conditions of the environment. Remote sensing methods provide opportunities for characterization and monitoring of the wetland on various scales that have not been done so far. In the present study satellite multispectral images from the European Union Copernicus Satellite program, Sentinel 2 are used, for assessing and monitoring of the actual state of the lake. Based on these satellite images, the boundaries of the protected wetland are derived. An index classification of the wetland was made. Normalized Difference Vegetation Index (NDVI) is used to classify sites within the protected area. Sentinel-2 satellite data to implement the orthogonal transformation model called Tasseled Cap Transformation (TCT) has also been used. The model is an effective method for classifying and analyzing of the processes related to the dynamics of changes, affecting the main components of the earth's surface: soil, water and vegetation. The spring survey of 2019 was selected for the present study. The results will show successful mapping and monitoring of the wetland, which will give a real idea of the state of the Durankulak Lake and the need to take conservation measures to protect it.

Key words: monitoring, satellite data, wetlands, habitats

POLLEN GIVING PLANTS VISITED BY THE HONEY BEE (APIS MELLIFERA L.)

Zheko Radev

Absract: The analysis of the honey plants in the area of apiculture is very important about the development, reproduction and productivity of bee colonies. The knowledge of the floral specialization of Apis mellifera L. is main point for good beekeeping practices. The bees have visited 46 species of honey plants from 41 genera and 22 families. The honey bees prefer to collect pollen from 2 to 5-6 plant species during every single month. Bees mainly collect pollen from two or three plants every month. The agricultural species Brassica napus as well as the meadow flora- Сentaurea solstitialis and Centaurea cyanus are the most visited honey plants during their flowering. Bees prefer to collect pollen from 16 plants out of 46 visited taxons. Not all plants in the area serve as a source of pollen for the bees. The greatest amount of collected pollen comes from Brassica napus- 3798.69 g. The visited cultivated honey taxons are around 22% but about 56.5% of the total amount collected pollen. Around 78% of the visited plants are common natural as well as about 43.5% of the total amount collected pollen.

Key words: honey bee, honey plants, pollen, pollen traps, melissopalynologia, specialization

GERMINATION OF TANACETUM CINERARIIFOLIUM SEEDS ON DIFFERENT SOIL TYPES

Vladimir Ilinkin

Abstract: Tanacetum cinerariifolium (Trevir.) Sch. Bip. is a species of great economic importance because it contains Pyrethrins – natural insecticides with the potential to be the ideal means for pest control. Soil samples from different soil types (Skeletic Fluvisols, Rendzic Leptosol, Luvic Chernozem, Chromic Luvisols, Dystric-Eutric Cambisol, Pellic Vertisols) have been studied in order to determine the physicochemical soil indicators and the regressions between the soil characteristics and seed germination. Four hundred seeds (4х100) were planted in each soil type (in pots) under controlled conditions. Reliable statistically significant regressions, both negative (bulk density, sand fraction, available phosphorus) and positive (total porosity, silt and clay fractions, pH(H₂O), CaCO₃, TKN, SOM) with regard to seed germination have been established. The seeds planted in Rendzic Leptosol have shown the highest germination percentage, and the ones planted in Skeletic Fluvisols have shown the lowest germination percentage.

Key words: Pyrethrum cinerariifolium Trev., Chrysanthemum cinerariifolium Bocc, seed germination, soil.

LABORATORY EXPERIMENTS AND MATHEMATICAL MODELLING OF ANAEROBIC DIGESTION OF ORGANIC WASTES IN A CASCADE OF TWO BIOREACTORS

Ivan Simeonov

Abstract. Anaerobic digestion processes have been investigated in a cascade of two bioreactors, constructed and fulfilled at the Institute of Microbiology of the Bulgarian Academy of Sciences. The first one is a 2 L working volume bioreactor and the 2^nd one – 12 L. A mixture of activated sludge from the Municipal Waste Waters Treatment Plant and milk whey has been digested in a continuous operation type, measuring the biogas flow rates and COD of the effluents of each bioreactor. With a double increase in the dilution rate for the first BR (D₁), the daily biogas yield of BR₁ (Q₁) increases about twice, and that of BR₂ (Q₂) does not change (which is also normal given the small value of D₂). The decrease of COD_total at the output of BR₂ compared to that of BR1 is 1.5 times, and that of COD_soluble 3 times.

A mathematical model has been developed on the basis of a mass balance of the input – output flows for this cascade of two anaerobic bioreactors. Simulation studies have been performed using Simulink of Matlab.

Keywords: anaerobic digestion, cascade of two bioreactors, laboratory experiments, activated sludge, milk whey, biogas flow rate, COD, mathematical model, simulation

СЪДЪРЖАНИЕ

Х. Найденски 3-4

I. МИКРООРГАНИЗМИ И ОКОЛНА СРЕДА