The soil C stock is a consequence of the balance between the C losses by the CO2 emission (associate to the heterotrofic microorganisms activity) and erosion, and to C inputs, associate to organic compounds input by the vegetal photosynthesis process. In order to evaluate the soil tillage and crop systems regarding to the C inputs by the residues and the C losses by the CO2 evolution and its consequences on the soil C stocks, a long term experiment (19 years) was carried out over a Rhodic Hapludox. This experiment is located in FUNDACEP, Cruz Alta, RS, Brazil. The main treatments were soil tillage systems: conventional tillage (CT) and no-tillage (NT). Subplots were tree commercial crop systems: winter wheat/soybean defined as monocropping system (R0), black oat/soybean/winter wheat/soybean defined as a winter crop rotation system (R1), and black oat/soybean/black oat+common vetch/maize/oil radish/winter wheat/soybean (R2) defined as intensive crop rotation system. The soil in NT system, averaged over crop systems, showed higher SOC and TN stocks and their particulate pools than the soil in CT on the shallow soil layer (0 - 5 cm), while the CT showed higher particulate organic carbon and nitrogen stocks (POC and PN) on the 5 - 10 cm layer. The soil in NT showed 1.6% more SOC than CT, averaged on the rotation systems, estimated by the layer equivalent method. To the mass equivalent method this difference increase to 4.5%. The crop rotation R2 associated to the NT (NT R2) showed higher mineral-associated carbon, SOC, mineral-associated N and TN stocks than the others treatments, on the 0 30 cm layer. The soil organic matter restoration was more influenced by the crop rotations systems, with high biomass input, than the tillage system adopted. This result most likely is due to differences in the biomass inputs. Once the NT, in averaged on crop systems, resulted in only 14% higher C addition than the CT. When associated to the R2 (NT R2) this difference increased to 68% compared to the CT without crop rotation (CT R0). The C-CO2 losses, evaluated by CO2 flux, were similar among treatments (soil tillage and crop systems), it is mostly influenced by the moisture and soil temperature. / O estoque de C no solo é conseqüência do balanço entre a saída de C pela emissão de CO2 (devido à atividade de microrganismos heterotróficos) e erosão e, a entrada de C, principalmente pela adição de compostos orgânicos sintetizados no processo de fotossíntese vegetal. Visando avaliar sistemas de preparo do solo e de culturas quanto a entrada de C orgânico pelos resíduos e saída pela evolução de CO2 e sua conseqüência no estoque de C orgânico no solo, foi desenvolvido essa pesquisa em experimento de longa duração (19 anos) sob Latossolo Vermelho distrófico típico. O experimento está situado na Fundação Centro de Experimentação e Pesquisa Fecotrigo (FUNDACEP), Cruz Alta, RS. Neste são conduzidos os preparos de solo convencional (PC) e plantio direto (PD) e, foram selecionados três sistemas comerciais de culturas: monocultura trigo/soja (R0); rotação de inverno aveia/soja/trigo/soja (R1) e, rotação de inverno e verão aveia/soja/aveia+ervilhaca/milho/nabo/trigo/soja (R2), em cada sistema de preparo do solo. As avaliações foram realizadas nas profundidades de 0-5, 5-10, 10-20 e 20-30 cm. O solo em PD, na média dos sistemas de culturas, apresentou maior teor e estoque de C orgânico e N total e fracionados que o solo em PC na camada superficial do solo (0-5 cm), enquanto que o solo sob PC apresentou, mais C orgânico e N total particulado (COP e NTP) na camada de 5-10 cm. O solo em PD apresentou 1,6% mais COT do que o solo sob PC, na camada de 0-30 cm, na média dos sistemas de culturas, pelo cálculo da camada equivalente. No método de cálculo da massa equivalente esta diferença aumentou para 4,5%. A rotação culturas R2 associada ao PD (PD R2) apresentou mais COAM, COT, NTAM e NT que os demais tratamentos, na camada de 0-30 cm. A recuperação do estoque de matéria orgânica do solo foi mais influenciada pelo sistema de rotação de culturas, que incluíram espécies de alto aporte de resíduos orgânicos, do que pelo sistema de preparo de solo. Este comportamento ocorreu devido às diferenças de aporte de resíduos vegetais. As culturas em PD, em média, forneceram apenas 14% mais C ao solo, do que as sob PC, mas quando associado à rotação de culturas R2 com PD (PD R2) esta diferença aumentou para 68% quando comparado a monocultura em PC (PC R0). A perda de C-CO2, avaliada pela evolução de CO2, foi similar entre os tratamentos (sistemas de preparo do solo e culturas), sendo influenciadas principalmente pela temperatura e umidade do solo.

<p>Eksperimentalnim istraživanjem u okviru doktorske teze utvrđen je trend promene fizičko-hemijskih parametara: mutnoća, temperatura, provodljivost i pH vode, koncentracija katjona Cd2+, As3+, Hg2+ i Pb2+, ukupnog azota, fosfora i sulfatnog ajona u vodi i sedimentu, na lokalitetu Zapadne Srbije, slivno područje akumulacije Vrutci u 2003/2014. Rezultati istraživačkih aktivnosti predstavljali su osnovu za razvoj regresionog modela kojim se može predvideti koncentracija katjona teških metala u jezerskoj vodi. Primenom klaster analize, dendograma i PCA analize dobijena su tri faktora na osnovu kojih se posmatra uticaj ključnih fizičko-hemijskih parametara na kvalitet vode zatvorenog vodnog tela akumulacije pri čemu su dobijene visoko korespodentne funkcionalne zavisnosti sa realnim podacima u jezeru. Ovakva istraživanja su po prvi put sprovedena za selektovani lokalitet u Srbiji.</p> / <p>Experimental studies in the doctoral thesis established the trend of changes in the physico-chemical parameters: turbidity, temperature, conductivity and pH of the water, the concentration of cations Cd, As, Hg and Pb, total nitrogen, phosphorus and sulphate anion in water and sediment at the site of Western Serbia, the catchment area of the reservoir Vrutci in 2003/2014. Results of research activities constituted the basis for the development of a regression model which can predict the concentration of heavy metal cations in lake water. Cluster analysis, dendograms and PCA (principal component analysis) were resulted by three factors, which could be possible to registre the impact of key physical and chemical parameters on the water quality of the closed lake reservoirs.The obtained results by multivariance analysis has showen the highly correspondent functional dependence with real data in a lake. Such research investigations were for the first time carried out in selected localities in Serbia.</p>

Black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) are two atmospheric pollutants produced by motor vehicles using carbonaceous fuels. As a part of the Mexico City Project, measurements of BC, PPAHs and many other gas- and particle-phase emissions were measured in Mexico City using a mobile laboratory during the Mexico City Metropolitan Area field campaign in April 2003 (MCMA-2003). The main goal of this research is to estimate emissions of BC and particulate PAHs (PPAHs) for Mexico City's vehicle fleet. The emissions of gas-phase pollutants such as carbon monoxide (CO), total nitrogen oxides (NOy) and volatile organic compounds (VOC) are also estimated. The mobile lab has previously been used to chase vehicles and measure their emissions, but analysis has traditionally focused on determining emission factors of individual vehicles associated with specific chasing events. The laboratory continuously samples ambient air from an inlet at the front of the van, and it is always "seeing" exhaust plumes from the vehicles around it while driving through traffic. We have developed an algorithm that automatically identifies the exhaust plume measurement points, which are then used as the basis for calculation of emission factors. In the nearly 90 hours of on-road sampling during the field campaign, we have identified ~30,000 exhaust measurement points. The large sample size enables us to estimate fleet-average emission factors and thus the emission inventory. Motor vehicles are estimated to emit annually 1,960 tons of BC, 56.2 tons of PPAHs, 1,320,000 tons of CO, 125,000 tons of NOy and 2440 tons of VOCs. The spatial and temporal patterns of BC and PPAHs in different locations with in MCMA are also studied. / Master of Science

Näringsämnena har en stor betydelse för sötvattnets organismer och ekosystem, varav de vanligaste näringsämnena som även är de viktigaste är fosfor (P), kväve (N) samt kol (C). Näringsämnena kommer inte enbart till sjön via nedfall och fixering utav mycket av näringsämnena kommer in till en sjö via vattendrag som till exempel älvar där Klarälven räknas in som en av Sveriges älvar. Syftet med denna studie är att ta fram en tidstrend mellan åren 1996 och 2013 för näringsämnena totalfosfor, totalkväve och TOC (totalt organiskt kol) för tio lokaler i norra Vänern för att kunna avgöra om de är lika, om det är något år som sticker ut, om det finns någon påverkan av Klarälven för de sjölokaler som tas upp och se om värdena av näringshalter kan kopplas till fiskförekomsten. Data samlades in och plottades i diagram för att kunna jämföras med varandra. Med sjölokalernas näringsvärde gjordes korrelationstester med älvarnas näringshalter för att se samband och därefter gjorde korrelation med sjölokalernas näringsvärden med andelen skördad fisk i samma lokaler. Resultatet visade att Ölman och Ölmeviken är väldigt eutrofierade medan resterande lokaler hade oligotrofa eller mesotrofa vatten och översvämningen i Karlstad 2000 visade avtryck i tidstrenden. Klarälvens påverkan på sjölokalerna visade sig inte vara så stor utan samband upptäcktes enbart mellan Kaplansådran och Hammarösjön för totalkvävet och för TOC upptäcktes samband mellan Hammarösjön och Sätterholmsfjärden med Kaplansådran. / The nutrient is very important for fresh water organisms and ecosystems, of which the most common nutrients also is the most important is phosphorus (P), nitrogen (N) and carbon (C). The nutrients will not only come into a lake through deposition and fixation, much of the nutrients is coming into the lake through rivers such as Klarälven in Sweden. The purpose of this study is to develop a temporal and spatial trend during 1996-2013 for the nutrients total phosphorus, total nitrogen and TOC (total organic carbon) for ten premises in northern Lake Vänern to determine if they are equal, if it is a year that stands out from the rest, if there is any influence of Klarälven for the lake premises and see if the values of the nutrient concentrations can be linked to the presence of fish. Data were collected and plotted in graphs to be compared with each other. Correlation test was made with the lake premises nutrient values and rivers nutrient value to see if there was a connection between the locations, same correlation was also made between the lake premises nutrient values and the percentage of fish harvested in the same premises. The result showed that Ölman and Ölmeviken is very eutrophic, while the remaining premises hade oligotrophic or mesotrophic water and the flooding in Karlstad in 2000 showed imprint in the time trend. The impact of Klarälven on the lake premises proved to not be so great, but the context was detected only between Kaplansådran and Hammarösjön for the total nitrogen and correlation for TOC between Hammarösjön and Sätterholmsfjärden with Kaplansådran was also detected.

<p>This report is commissioned by the Water and Sewage Agency in The City of Mariehamn, Åland. The basic aim is to investigate positive or negative effects of a relocation of the sewage pipe from a wastewater treatment plant, Lotsbroverket. The environmental licence of Lotsbroverket is to be revised and The Environmental Appeal Board at Åland’s Government and Administrative Board has made demands that several possible locations in an outer water area should be examined. The present location of the sewage pipe is in Svibyviken, which has been classified as an “inner water area”.</p><p>The objective of this work is to study to which extent the nutrient loading from Lotsbroverket influence the environmental conditions in Svibyviken, and to investigate the suitability of different locations of the wastewater pipe from Lotsbroverket.</p><p>The way a coastal area looks, i.e., its morphometry, determines to a large extent its ecological characteristics. The investigated coastal area was digitalized from a nautical chart. The software used for this was Roots 3.3 and the GIS-tool ArcGIS 8.3. The localization of the coastal boundaries for the entire coastal area and for investigated sub-areas was determined according to the topographical bottleneck method, i.e., the boundary lines were drawn where the exposure of the coast to the open sea is minimized.</p><p>A process-based dynamic mass-balance model for total phosphorous has been used in this study. Using this model, one can estimate and quantify the effects of different nutrient sources in coastal areas. All the fluxes of phosphorous to, from and within the defined areas were studied and ranked. Model simulations have shown how changes in any of the phosphorous fluxes influence the mean monthly concentrations of total phosphorous. The situation for total nitrogen was determined with a statistical/empirical regression model between phosphorous and nitrogen concentrations. To estimate the expected ecological effects from a change in the nutrient loading from Lotsbroverket, statistical/empirical correlations between modelled nutrient concentrations and ecological effect variables have been used. Standard effect variables for the study of eutrophication effects in coastal areas are, e.g., the chlorophyll concentration, Secchi depth and oxygen saturation in deep water. These variables have also been used in this study.</p><p>It has been shown that (1) the nutrient concentrations of the Baltic Sea controls the concentration of nutrients in the studied areas to a very large extent, (2) that the nutrient fluxes from Lotsbroverket are small compared to the nutrient fluxes from the Baltic Sea and hence also of minor importance for the nutrient state of the receiving water system, (3) that the influence of the nutrient emissions from Lotsbroverket are most noticeable in the present inner recipient, Svibyviken, and (4) that the impact logically decreases with distance between the location of the sewage pipe and boundary line to the open sea. The overall conclusion is that no major improvement of the conditions in Svibyviken can be expected by a reduction or a relocation of the nutrient emissions from Lotsbroverket.</p> / <p>Detta examensarbete är ett uppdrag av VA-verket vid Mariehamns stad, Åland, med syfte att utreda effekter av en eventuell flyttning av avloppsreningsverket Lotsbroverkets utloppsledning. Inför en revidering av Lotsbroverkets miljötillstånd har Miljöprövningsnämnden vid Ålands landskapsregering ställt villkor på att tillståndshavaren skall utreda möjligheter till att avleda det renade avloppsvattnet till ett yttre vattenområde. Utloppsledningen mynnar i dagsläget i Svibyviken, vilken har klassificerats som ett inre vattenområde.</p><p>Målsättningen med detta arbete är att belysa vilka ekologiska effekter näringsämnesutsläppet från Lotsbroverket har på primärrecipienten Svibyviken samt att undersöka några andra områdens lämplighet som mottagare av avloppsvattnet. Ett kustområdes utseende och form, det vill säga dess morfometri, avgör i stor utsträckning dess ekologiska förhållanden. För att få en god bild av det undersökta områdets morfometri digitaliserades området utifrån ett sjökort i digitaliseringsprogrammet Roots 3.3, varefter data bearbetades med GIS-verktyget ArcGIS 8.3. Avgränsning av kustområdet som helhet och av undersökta delområden gjordes enligt den topografiska flaskhalsmetoden, det vill säga så att kustens öppenhet mot utanförliggande hav eller vattenområde minimeras (Håkanson et al., 1984; Pilesjö et al., 1991).</p><p>För arbetet har en processbaserad, dynamisk massbalansmodell för totalfosfor använts. Modellen har tagits fram för att eutrofieringseffekter i kustområden skall kunna studeras (Håkanson & Karlsson, 2001). Vid användandet av modellen kan effekter av olika näringsämneskällor uppskattas och kvantifieras. Samtliga totalfosforflöden till, från och inom olika avgränsade områden har studerats och rangordnats. Modellsimuleringar har visat hur förändringar i något av fosfortillflödena inverkar på recipientens månadsmedelkoncentration av totalfosfor. Situationen för kväve har undersökts med hjälp av en statistisk/empirisk regressionsmodell mellan fosfor- och kvävehalt. För att belysa de ekologiska effekter som kan förväntas efter en förändring av Lotsbroverkets fosfor- och kväveutsläpp har statistiska/empiriska kopplingar gjorts mellan näringsämneskoncentrationer och ekologiska effektvariabler. Bra effektvariabler vid undersökning av eutrofieringseffekter är exempelvis klorofyllhalt, siktdjup samt syrgashalt i bottenvattnet. Dessa variabler har också använts i detta arbete.</p><p>Resultaten visar att (1) närsaltskoncentrationerna i de studerade områdena i hög grad styrs av den allmänna eutrofieringsnivån i Östersjön, (2) att utsläppet av näringsämnen från Lotsbroverket inte inverkar på recipientens näringsstatus i någon stor utsträckning, (3) att Lotsbroverkets påverkan är störst på nuvarande recipient, Svibyviken, (4) och att påverkan sedan successivt minskar ju längre ut mot öppna havet utloppsledningen lokaliseras. Slutsatsen av utredningen är att en reduktion av Lotsbroverkets utsläpp eller nylokalisering av utloppsledningen inte kan förväntas ge någon omfattande förbättring av tillståndet i Svibyviken.</p>

This report is commissioned by the Water and Sewage Agency in The City of Mariehamn, Åland. The basic aim is to investigate positive or negative effects of a relocation of the sewage pipe from a wastewater treatment plant, Lotsbroverket. The environmental licence of Lotsbroverket is to be revised and The Environmental Appeal Board at Åland’s Government and Administrative Board has made demands that several possible locations in an outer water area should be examined. The present location of the sewage pipe is in Svibyviken, which has been classified as an “inner water area”. The objective of this work is to study to which extent the nutrient loading from Lotsbroverket influence the environmental conditions in Svibyviken, and to investigate the suitability of different locations of the wastewater pipe from Lotsbroverket. The way a coastal area looks, i.e., its morphometry, determines to a large extent its ecological characteristics. The investigated coastal area was digitalized from a nautical chart. The software used for this was Roots 3.3 and the GIS-tool ArcGIS 8.3. The localization of the coastal boundaries for the entire coastal area and for investigated sub-areas was determined according to the topographical bottleneck method, i.e., the boundary lines were drawn where the exposure of the coast to the open sea is minimized. A process-based dynamic mass-balance model for total phosphorous has been used in this study. Using this model, one can estimate and quantify the effects of different nutrient sources in coastal areas. All the fluxes of phosphorous to, from and within the defined areas were studied and ranked. Model simulations have shown how changes in any of the phosphorous fluxes influence the mean monthly concentrations of total phosphorous. The situation for total nitrogen was determined with a statistical/empirical regression model between phosphorous and nitrogen concentrations. To estimate the expected ecological effects from a change in the nutrient loading from Lotsbroverket, statistical/empirical correlations between modelled nutrient concentrations and ecological effect variables have been used. Standard effect variables for the study of eutrophication effects in coastal areas are, e.g., the chlorophyll concentration, Secchi depth and oxygen saturation in deep water. These variables have also been used in this study. It has been shown that (1) the nutrient concentrations of the Baltic Sea controls the concentration of nutrients in the studied areas to a very large extent, (2) that the nutrient fluxes from Lotsbroverket are small compared to the nutrient fluxes from the Baltic Sea and hence also of minor importance for the nutrient state of the receiving water system, (3) that the influence of the nutrient emissions from Lotsbroverket are most noticeable in the present inner recipient, Svibyviken, and (4) that the impact logically decreases with distance between the location of the sewage pipe and boundary line to the open sea. The overall conclusion is that no major improvement of the conditions in Svibyviken can be expected by a reduction or a relocation of the nutrient emissions from Lotsbroverket. / Detta examensarbete är ett uppdrag av VA-verket vid Mariehamns stad, Åland, med syfte att utreda effekter av en eventuell flyttning av avloppsreningsverket Lotsbroverkets utloppsledning. Inför en revidering av Lotsbroverkets miljötillstånd har Miljöprövningsnämnden vid Ålands landskapsregering ställt villkor på att tillståndshavaren skall utreda möjligheter till att avleda det renade avloppsvattnet till ett yttre vattenområde. Utloppsledningen mynnar i dagsläget i Svibyviken, vilken har klassificerats som ett inre vattenområde. Målsättningen med detta arbete är att belysa vilka ekologiska effekter näringsämnesutsläppet från Lotsbroverket har på primärrecipienten Svibyviken samt att undersöka några andra områdens lämplighet som mottagare av avloppsvattnet. Ett kustområdes utseende och form, det vill säga dess morfometri, avgör i stor utsträckning dess ekologiska förhållanden. För att få en god bild av det undersökta områdets morfometri digitaliserades området utifrån ett sjökort i digitaliseringsprogrammet Roots 3.3, varefter data bearbetades med GIS-verktyget ArcGIS 8.3. Avgränsning av kustområdet som helhet och av undersökta delområden gjordes enligt den topografiska flaskhalsmetoden, det vill säga så att kustens öppenhet mot utanförliggande hav eller vattenområde minimeras (Håkanson et al., 1984; Pilesjö et al., 1991). För arbetet har en processbaserad, dynamisk massbalansmodell för totalfosfor använts. Modellen har tagits fram för att eutrofieringseffekter i kustområden skall kunna studeras (Håkanson &amp; Karlsson, 2001). Vid användandet av modellen kan effekter av olika näringsämneskällor uppskattas och kvantifieras. Samtliga totalfosforflöden till, från och inom olika avgränsade områden har studerats och rangordnats. Modellsimuleringar har visat hur förändringar i något av fosfortillflödena inverkar på recipientens månadsmedelkoncentration av totalfosfor. Situationen för kväve har undersökts med hjälp av en statistisk/empirisk regressionsmodell mellan fosfor- och kvävehalt. För att belysa de ekologiska effekter som kan förväntas efter en förändring av Lotsbroverkets fosfor- och kväveutsläpp har statistiska/empiriska kopplingar gjorts mellan näringsämneskoncentrationer och ekologiska effektvariabler. Bra effektvariabler vid undersökning av eutrofieringseffekter är exempelvis klorofyllhalt, siktdjup samt syrgashalt i bottenvattnet. Dessa variabler har också använts i detta arbete. Resultaten visar att (1) närsaltskoncentrationerna i de studerade områdena i hög grad styrs av den allmänna eutrofieringsnivån i Östersjön, (2) att utsläppet av näringsämnen från Lotsbroverket inte inverkar på recipientens näringsstatus i någon stor utsträckning, (3) att Lotsbroverkets påverkan är störst på nuvarande recipient, Svibyviken, (4) och att påverkan sedan successivt minskar ju längre ut mot öppna havet utloppsledningen lokaliseras. Slutsatsen av utredningen är att en reduktion av Lotsbroverkets utsläpp eller nylokalisering av utloppsledningen inte kan förväntas ge någon omfattande förbättring av tillståndet i Svibyviken.

Η μελέτη ενός πειράματος μικρής πιλοτικής κλίμακας, με δύο παράλληλα συστήματα ρηχών λεκανών (ύψους 0.35m), η μία λεκάνη με φύτευση του είδους Typha Latifolia και η άλλη χωρίς φύτευση, διεξάχθηκε για τον σχεδιασμό ελεύθερης επιφανειακής ροής (FWS) τεχνητού υγροτόπου. Οι δύο λεκάνες τροφοδοτήθηκαν με πραγματικά αστικά λύματα όπου οι χρόνοι παραμονής κυμάνθηκαν από 27,6 έως 38,0 ημέρες. Η μεταβολή του όγκου κάθε λεκάνης παρακολουθήθηκε για 2 συνεχή έτη και ταυτόχρονα υπολογίστηκαν οι ρυθμοί βροχόπτωσης και εξάτμισης. Η διαφορά του όγκου μεταξύ των δύο λεκανών οφειλόταν στην πρόσληψη νερού από τα φυτά, η οποία συγκρίθηκε με τις προβλέψεις της εξατμισοδιαπνοής παρόμοιων φυτών με την χρήση του υπολογιστικού προγράμματος REF-ET. Η συγκομιδή των φυτών πραγματοποιήθηκε τρείς φορές στην διάρκεια του 1ου έτους του πειράματος, ώστε να εκτιμηθεί ο ρυθμός πρόσληψης αζώτου από τα φυτά. Η σημαντικότερη διαφορά των δύο συστημάτων ήταν η αφαίρεση νερού μέσω της εξατμισοδιαπνοής των φυτών. Η πιλοτική μονάδα λειτούργησε έτσι ώστε να επιτευχθεί και απομάκρυνση της οργανικής ύλης (BOD5) και του ολικού αζώτου (TN) από τα λύματα. Ο σχεδιασμός της διευκόλυνε την ανάπτυξη ενός μαθηματικού μοντέλου, ακολουθώντας το πλαίσιο του μοντέλου της ενεργής ιλύος (ASM). Αρχικά το μαθηματικό μοντέλο αναπτύχθηκε για τις δύο λεκάνες με τις μικροβιακές διεργασίες που επικράτησαν στο εσωτερικό τους, ώστε να περιγραφεί πλήρως η συμπεριφορά τους. Η προσομοίωση και η εκτίμηση των παραμέτρων του μοντέλου επιτεύχθηκε με την χρήση του υπολογιστικού περιβάλλοντος του AQUASIM. Οι κύριες διεργασίες που ελήφθησαν υπόψη για την μοντελοποίηση ήταν η αμμωνιοποίηση, η αερόβια ετεροτροφική ανάπτυξη, η νιτροποίηση και η ανάπτυξη φυκών. Μια ισχυρή εποχική εξάρτηση παρατηρήθηκε για την συμπεριφορά κάθε λεκάνης όταν το μοντέλο εφαρμόστηκε για το 1ο έτος του πειράματος. Αυτό το μοντέλο επαληθεύτηκε ικανοποιητικά με τα πειραματικά δεδομένα του 2ου έτους. Η παρατηρούμενη μέση ετήσια απόδοση απομάκρυνσης του BOD5 και του TN ήταν 60% και 69%, αντίστοιχα για την λεκάνη χωρίς φυτά και 83% και 75%, αντίστοιχα για την λεκάνη με φυτά. Το μοντέλο προέβλεψε μέση ετήσια απόδοση απομάκρυνσης 82% για το BOD5 και 65% για το TN στην λεκάνη με φυτά, ικανοποιώντας τα κριτήρια για τον σχεδιασμό πλήρους κλίμακας τεχνητού υγροτόπου . Η ικανότητα του μοντέλου να προβλέπει όχι μόνο την απομάκρυνση της οργανικής ύλης αλλά και του ολικού αζώτου, θεωρήθηκε επαρκής όταν δοκιμάστηκε με έναν ελεύθερης επιφανειακής ροής τεχνητό υγρότοπο με 400 ισοδύναμο πληθυσμό, με μοναδική τροποποίηση τον συνυπολογισμό του περιορισμού του οξυγόνου στον ρυθμό της διεργασίας της νιτροποίησης. Επομένως, το δυναμικό μοντέλο διαμορφώθηκε με την ενσωμάτωση της πρόβλεψης του ρυθμού της εξατμισοδιαπνοής των φυτών και χρησιμοποιήθηκε για τον σχεδιασμό περίπτωσης μελέτης τεχνητού υγροτόπου πλήρους κλίμακας. Τα στοιχεία που απαιτούνται για αυτό τον σχεδιασμό περιλάμβαναν την παροχή εισόδου και κλιματολογικά στοιχεία (θερμοκρασίας και βροχόπτωσης) για την περιοχή του σχεδιασμού, καθώς και οι απαιτήσεις της ποιότητας εκροής. Η περίπτωση μελέτης για 4000 ισοδύναμο πληθυσμό όπου η ποιότητα εκροής ήταν σε μέσες ετήσιες τιμές BOD5=25mg/L και TN=15mg/L, χρειάστηκε μία συνολική επιφάνεια υγροτόπου 11 εκταρίων. Εάν χρησιμοποιηθούν δύο λεκάνες σε σειρά, η 1η με φυτά και η 2η χωρίς, τότε η συνολική επιφάνεια μειώνεται κατά περίπου 27%, ελέγχοντας μόνο την αρχική μέγιστη φύτευση της πρώτης λεκάνης του υγροτόπου. / The study at pilot-scale of two parallel systems with shallow basins (height h=0.35m), one planted with Typha Latiofolia and the other without vegetation, was conducted for the modeling of free water surface (FWS) constructed wetland systems. The basins were fed with real sewage at retention times ranging from 27.6 to 38.0 days. The variation of the volume in each basin was monitored for two consecutive years and simultaneously, rainfall and evaporation rates were calculated. The difference of the volume between the basins was due to the water absorption by the plants and was compared with the predictions of evapotranspiration rates of similar plants using the REF-ET calculation software. The harvesting of the plants was performed three times during the first year, in order to estimate the nitrogen uptake by the plants. The main difference in the two systems was the water removal through plant evapotranspiration. The pilot unit was operated so as to achieve the removal of both organic matter (BOD5) and total nitrogen (TN) from the sewage. Its design enabled the development of a mathematical model, following the framework of the activated sludge model (ASM). The simulation and the parameter estimation were achieved using the AQUASIM framework. The mathematical model describes the microbial processes, which dominated within the basins describing satisfactorily their behavior. The key processes accounted for in the modeling were ammonification, aerobic heterotrophic growth, nitrification and algal growth. A strong seasonal dependence was observed for each basin. The model was satisfactorily validated with the data of the second year. An observed average annual removal efficiency of BOD5 and TN were 60% and 69%, respectively for the basin without plants and 83% and 75%, respectively for the basin with plants. The model predicted average annual removal efficiency 82% for BOD5 and 65% for TN in the basin with plants, satisfying the design criteria of a full-scale constructed wetland. The ability of the model to predict not only the removal of organic matter but also total nitrogen removal, was considered sufficient as tested with a real free water surface constructed wetland of 400 population equivalent, with the sole modification being the inclusion of oxygen limitation in the nitrification rate. The dynamic model was amended with the direct incorporation of the plant evapotranspiration rate and it was used to design a full-scale constructed wetland. The required elements for this design included the inflow rate and climatic data (temperature and rainfall) for the design region, as well as the effluent quality requirements. In the case study of 4000 population equivalent, the effluent quality requirement was: average annual values for BOD5=25mg/L and for TN=15mg/L. The model was used to determine a total wetland surface requirement of 11ha. If two sequential basins are used, the first with plants and the second without, then the total wetland surface could be reduced by approximately 27%, controlling only the maximum initial vegetation in the first wetland basin.

Thesis (PhD (Chemical Engineering))--Cape Peninsula University of Technology, 2019 / Simultaneous nitrification and aerobic denitrification (SNaD) is a preferred method for single stage total nitrogen (TN) removal, which was recently proposed to improve wastewater treatment plant design. However, SNaD processes are prone to inhibition by toxicant loading with free cyanide (CN-) possessing the highest inhibitory effect on such processes, rendering these processes ineffective. Despite the best efforts of regulators to limit toxicant disposal into municipal wastewater sewage systems (MWSSs), free cyanide (CN-) still enters MWSSs through various pathways; hence, it has been suggested that CN- resistant or tolerant microorganisms be utilized for processes such as SNaD. To mitigate toxicant loading, organisms in SNaD have been observed to adopt a multiphase growth strategy to sequentially degrade CN- during primary growth and subsequently degrade TN during the secondary growth phase. However, CN- degrading microorganisms are not widely used for SNaD in MWSSs due to the inadequate application of suitable microorganisms (Chromobacterium violaceum, Pseudomonas aeruginosa, Thiobacillus denitrificans, Rhodospirillum palustris, Klebsiella pneumoniae, and Alcaligenes faecalis) commonly used in single-stage SNaD. The use of CN- degrading or resistant microorganisms for SNaD is a cost-effective method compared to the use of other methods of CN- removal prior to TN removal, as they involve multi-stage systems (as currently observed in MWSSs). The use of CN- degrading microorganisms, particularly when used as a consortium, presents a promising and sustainable resolution to mitigate inhibitory effects of CN- in SNaD. However, SNaD is known to be completely inhibited by CN- thus it is imperative to also study some thermodynamic parameters of SNaD under high CN- conditions to see the feasibility of the process. The Gibbs free energy is significant to understand the feasibility of SNaD, it is also vital to study Gibbs free energy to determine whether or not the biological reaction is plausible. The relationship between the rate of nitrification and Gibbs free energy was also investigated. The attained results showed that up to 37.55 mg CN-/L did not have an effect on SNaD. The consortia degraded CN- and achieved SNaD, with degradation efficiency of 92.9 and 97.7% while the degradation rate of 0.0234 and 0.139 mg/L/hr for ammonium-nitrogen (NH4-N) and CN- respectively. Moreover, all the free Gibbs energy was describing the individual processes were found to be negative, with the lowest Gibbs free energy being -756.4 and -1830.9 Kcal/mol for nitritation and nitratation in the first 48 h of the biological, reaction respectively. Additionally, a linear relationship between the rate of NH4-N and nitrite-nitrogen (NO2-N) degradation with their respective Gibbs free energy was observed. Linear model was also used to predict the relationship between NH4-N, NO2-N degradation and Gibbs free energy. These results obtained showed a good correlation between the models and the experimental data with correlation efficiency being 0.94 and 0.93 for nitritation, and nitratation, respectively. From the results found it can be deduced that SNaD is plausible under high cyanide conditions when cyanide degrading or tolerant microorganisms are employed. This can be a sustainable solution to SNaD inhibition by CN- compounds during wastewater treatment. Furthermore, a single strain was purified from the consortium and identified as Acinetobacter courvalinii. This bacterial strain was found to be able to perform sequential CN- degradation, and SNaD; an ability associated with multiphase growth strategy of the microorganism when provided with multiple nitrogenous sources, i.e. CN- and TN. The effect of CN- on nitrification and aerobic denitrification including enzyme expression, activity and protein functionality of Acinetobacter courvalinii was investigated. It was found that CN- concentration of up to 5.8 mg CN-/L did not affect the growth of Acinetobacter courvalinii. In cultures whereby the A. courvalinii isolate was used, degradation rates of CN- and NH4-N were found to be 2.2 mg CN-/L/h and 0.40 mg NH4-N/L/h, respectively. Moreover, the effect of CN- on NH4-N, nitrate-nitrogen (NO3-N) and NO2-N oxidizing enzymes was investigated, with findings indicating CN- did not affect the expression and activity of ammonia monooxygenase (AMO), but affected the activity of nitrate reductase (NaR) and nitrite reductase (NiR). Nevertheless, a slow decrease in NO2-N was observed after the addition of CN- thus confirming the activity of NaR and the activation of the denitrification pathway by the CN-. Moreover, five models’ (Monod, Moser, Rate law, Haldane, and Andrew’s model) ability to predict SNaD under CN- conditions, indicated that only Rate law, Haldane and Andrew’s models, were suited to predict both SNaD and CN- degradation. Due to low degradation rates of NH4-N and CN-, optimization of SNaD was essential. Therefore, response surface methodology was used to optimize the SNaD under CN- conditions. The physiological parameters that were considered for optimization were temperature and pH; with the result showing that the optimum for pH and temperature was 6.5 and 36.5oC respectively, with NH4-N and CN- degradation efficiency of 50 and 80.2%, respectively. Furthermore, the degradation kinetics of NH4-N and CN- were also studied under the optimum conditions in batch culture reactors, and the results showed that up to 70.6% and 97.3% of NH4-N and CN- were simultaneously degraded with degradation rates of 0.66 and 0.41 mg/L/h, respectively. The predictive ability of RSM was further compared with cybernetic models, and cybernetic models were found to better predict SNaD under CN- conditions. These results exhibited a promising solution in the management of inhibition effected of CN- towards SNaD at an industrial scale.

Syftet var att finna en biologisk behandlingsmetodik för avloppsvatten som skullekunna reducera utsläpp av näringsämnen till recipienten Humlebäcken frånavloppsreningsverket (ARV) i Nyvång. Nyvångs reningsverk planeras uppgraderas och utökas och därtill har ärendet nekats då utsläpp till Humlebäcken förfaras bli för höga. Mikroalger som behandlingsmetod för avloppsvatten undersöktes via litteraturanalys ibåde svenska klimat och vid uppskalning. Det kunde inte hittas metodik eller teknik för att på industriell skala använda mikroalger till behandling av avloppsvatten idag. Dock presenteras flera olika tekniker som kan kopplas samman för ökad effektivitet. Vidare finns det stor potential om att mikroalgssystem kan kopplas samman med andra industriers spillvärme och rökgaser för ökad produktion av biomassa och rening av rökgas. Andra former av kemisk försedimentering och anaerob behandling från Energipositiv Rening presenteras, möjligheten finns att dessa kan kopplas samman med mikroalgssystem för komplett behandling till lägre kostnader av konventionell behandlingsteknik. Till slut presenteras påverkande faktorer vid nordiska klimat och utmaningar i form av striktare reningskrav och återföring av slam. Det presenteras kort om andra biologiska tekniker som svampodling och multitrofiskt vattenbruk vilka kan kopplas samman medmikroalgssystem för ökad resurseffektivitet och högre reningsgrad. Se figur 18 förgrafisk summering. / The purpose was to find a biological treatment method for wastewater which could reduce emissions of nutrients to the recipient Humlebäcken from the wastewater treatment plant (WWTP) in Nyvång. Since Nyvång WWTP plans to upgrade and expand have been denied for fears of further contamination of Humlebäcken. Microalgae as a treatment method was examined in this literature analysis for Swedish climates and upscaling. For industrial purposes no technique or method could befound which could be applied to wastewater currently. Several techniques are presented however in the hopes that in combining them a higher efficiency might beachieved. If microalgae systems could be integrated with waste heat and flue gas from industry, then higher productivity could be achieved whilst reducing emissions from the flue gas. Other forms of pre-sedimentation and anaerobic treatment methods from EnergyPositive Purification systems are presented as there's a possibility these can be connected to microalgae systems for complete treatment and less costs. Factors which affect microalgae cultivation in Nordic climates and challenges in terms of stricter emission requirements and reuse of sludge are presented lastly. Other biological treatment methods like mushroom and multi-trophic aquaculture which can be integrated to microalgae systems are shown in hopes of achieving higher resource efficiency and pollution reduction. See figure 18 for graphical abstract.