Die Broschüre vermittelt einen Überblick über die Versorgung sächsischer Ackerböden mit Mikronährstoffen. Die aktuelle Situation wird mit den Ergebnissen des Monitorings im Jahr 2000 verglichen. Der Versorgungszustand sächsischer Ackerflächen mit pflanzenverfügbaren Mikronährstoffen ist zumeist gut bis sehr gut. Gegenüber dem Jahr 2000 ist ein leichter Rückgang der Elementgehalte bei Cu, B und teilweise bei Zn festzustellen. Leichte Böden (D-Standorte) weisen vereinzelt Mangel auf (Mn, Mo, B). Für die Analyse der pflanzenverfügbaren Anteile ist die CAT-Methode für Kupfer und Zink (und evtl. Mangan) anwendbar. Bor sollte mit der Heißwassermethode analysiert werden, Die Analyse von Molybdän erfolgt am besten mit der Oxalatmethode nach GRIGG. Die Veröffentlichung richtet sich an Landwirte, Berater und Fachbehörden.

On solid surfaces, laboratory strain Saccharomyces cerevisiae BY4742 forms horizontally and vertically stratified colonies. Central part of the colony differentiates into U and L cells occupying upper and lower colony regions, respectively. There are many morphological and physiological differences between these two cell types. However, molecular mechanisms of the vertical stratification are still largely unknown. In this study, I analyzed effects of the deletion and overexpression of Sch9p a Rim15p kinases with crucial role in nutrient sensing pathways, of transcription activators Msn2p and Msn4p involved i stress response and of post-diauxic shift transcription factor Gis1p in yeast colony differentiation and U and L cell survival. Microscopic analyses showed changes in morphology of cells in colonies of these strains and decreased ability of vertical stratification in colonies of the strain rim15Δ and partially in colonies of the strain PTEF-SCH9. Moreover, changed level of these proteins significantly affected long-term survival of U and L cells. Obtained data suggest an involvement of nutrient sensing pathways in colony formation and development.

Fishpond ecosystems provide many other services besides fish production. One of them is the retention of nutrients and thus ability to change the quality of the through flowing water, thereby ability to influence the overall quality of surface waters. In the case of the fishpond Svět in Třeboň it is also recreation, as the pond is an integral part of the tourism of the town. Water quality in the fishpond and its retention capacity of phosphorus is connected with the fish management and the inflow of nutrients from the catchment basis, especially within a cascade of ponds and densely populated or agricultural regions. This thesis evaluates seasonal (2013, 2015) and long term (2007-2015) trend of water quality of pond Svět in Třeboň in relation to fish management. Furthermore, mass balance was calculated for 2015 and estimated for 2013. The years 2015 and 2013 (the first years of production cycle) varied considerably in amount of annual rainfall. The year 2015 was extremely dry and 2013 very aqueous. Different hydrological conditions caused different seasonal courses in hydrochemistry parameters and its concentrations. The water quality of fishpond Svět is in the most of parameters better in comparison with other production fishponds in the Třeboň region and also the intensity of fish management is...

L'utilisation des microalgues dans le traitement des eaux usées est de plus en plus étudiée pour intégrer/remplacer les systèmes de traitement actuels permettant d'éliminer les nutriments et autres polluants. Cependant, l’utilisation des microalgues dans le traitement des eaux usées en est principalement au stade de la recherche, par exemple faible élimination des nutriments et croissance de la biomasse des microalgues. Le but de cette thèse était de permettre une élimination efficace des éléments nutritifs et de la matière organique des eaux usées par les microalgues tout en favorisant la production de biomasse de microalgues. C. vulgaris et S. acuminatus ont été cultivés dans des photobioréacteurs discontinus avec des digestats issus de la digestion anaérobie (AD) de boues biologiques de boue de vidange provenant d’une station d’épuration municipale (ADMW) et d’une usine de traitement des eaux usées d’une usine de pâtes et papiers (ADPP). Les rendements d’élimination de l’ammonium étaient supérieurs à 97% lorsque les deux microalgues étaient cultivées séparément dans de l’ADPP. Toutefois, 24 et 44% de l’ammonium ont été retirés de l’ADMW par C. vulgaris et S. acuminatus, respectivement. Les deux microalgues ont efficacement éliminé le phosphate (> 96%), tandis que la couleur (74–80%) et la DCO soluble (27–39%) ont été partiellement éliminées de ADMW et d'ADPP. La plus forte concentration de biomasse de S. acuminatus (7,8 à 10,8 g L-1 VSS) dans l'ADPP figure parmi les rendements les plus élevés signalés pour les microalgues dans les eaux usées réelles. Des rendements de biomasse supérieurs de S. acuminatus ont été obtenus dans de l'ADPP thermophile (10,2 ± 2,2 et 10,8 ± 1,2 g L-1) par rapport à de l'ADPP mésophile prétraité (7,8 ± 0,3 g L-1). En outre, les concentrations les plus élevées en biomasse et en méthane de microalgues ont été obtenues dans le même système intégré de culture de AD et de microalgues. Les concentrations de fer (0,1, 1,0 et 1,9 mg L-1) et de sulfure de soufre (3,7, 20 et 35,8 mg L-1) affectaient davantage l'efficacité de l'élimination de l'azote et la concentration de la biomasse de microalgues davantage dans les ammonium probablement dû à différents mécanismes d'assimilation de microalgues. Dans cette étude, le milieu contenant du nitrate comme source d'azote avec 1,0 mg de L-1 de fer et 35,8 mg de L-1 de sulfate et de soufre a permis d'obtenir la plus forte concentration de biomasse de microalgues. L'effet de la concentration en fer sur l'efficacité d'élimination des nitrates et la croissance des microalgues était plus significatif que la concentration en sulfate, alors que l'effet d'interaction entre le sulfate et le fer n'était pas observé. L'efficacité moyenne d'élimination de l'ammonium (14 à 30%) et la concentration en biomasse de microalgues (0,55 à 1,17 g de POC L-1) dans un photobioréacteur à membrane à flux continu ont été améliorées par addition de zéolite (0,5 g L-1). La zéolite fournissait probablement un habitat pour la croissance attachée de microalgues et une grande disponibilité d'ammonium pour la croissance à la surface de la zéolite en raison de l'adsorption d'ammonium par la zéolite. Une augmentation supplémentaire de la concentration en zéolite (de 0,5 à 1 et 5 g L-1) n’a pas amélioré l’efficacité de l’élimination de l’ammonium ni la concentration de la biomasse, probablement en raison de la turbidité accrue de la solution provoquée par la fragmentation de la zéolite ajoutée en particules plus fines, ce qui a réduit la disponibilité de lumière. Ces travaux ont montré la possibilité d'utiliser des microalgues dans le traitement des eaux usées pour éliminer efficacement les nutriments et les matières organiques, tout en favorisant la croissance des microalgues. La sélection d'espèces de microalgues adaptées aux eaux usées spécifiques pour éliminer les nutriments et les matières organiques est essentielle pour promouvoir les applications de traitement des eaux usées à base d'algues / Use of microalgae in wastewater treatment has been increasingly studied to integrate with or replace the present treatment systems for removal of nutrients and other pollu-tants. The potential advantages of this integration (wastewater treatment and microalgal cultivation) could be simultaneous recovery of nitrogen and phosphorus and the use of produced microalgal biomass as feedstock for e.g. biofuel, fertilizer and/or energy. However, the use of microalgae in wastewater treatment is mainly in research stage due to e.g. low nutrient removal and microalgal biomass growth. The aim of this thesis was to enable efficient nutrient and organic matter removal from wastewaters by mi-croalgae while promoting microalgal biomass production. Chlorella vulgaris and Scenedesmus acuminatus were successfully grown in batch photobioreactors with liquid digestates from anaerobic digestion (AD) of biosludge from a municipal wastewater treatment plant (ADMW) and a pulp and paper mill wastewater treatment plant (ADPP). The final ammonium removal efficiencies were above 97% when cultivating both microalgae separately in ADPP, however, only 24% and 44% of ammonium were removed from ADMW by C. vulgaris and S. acuminatus, respectively. Both microalgae efficiently removed phosphate (>96%), while color (74–80%) and sol-uble COD (27–39%) were partially removed from ADMW and ADPP. The obtained highest S. acuminatus biomass concentration (7.8–10.8 g L-1 VSS) in ADPP is among the highest yields reported for microalgae in real wastewaters. Higher S. acuminatus biomass yields were obtained in thermophilic ADPP (without and with pretreatment prior to AD: 10.2±2.2 and 10.8±1.2 g L-1, respectively) than in pretreated mesophilic ADPP (7.8±0.3 g L-1). In addition, the highest microalgal biomass concentration and methane yields were obtained in the same integrated AD and microalgal culti-vation system (thermophilic AD with pretreatment).The iron (0.1, 1.0, and 1.9 mg L-1) and sulfate-sulfur (3.7, 20, and 35.8 mg L-1) concen-trations were found to affect nitrogen removal efficiency and microalgal biomass con-centration more in the media with nitrate than with ammonium, probably due to different microalgal assimilation mechanisms for nitrate and ammonium. In this study, synthetic medium with nitrate as nitrogen source with 1.0 mg L-1 iron and 35.8 mg L-1 sulfate-sulfur enabled the highest microalgal biomass concentration. The effect of iron concentration on nitrate removal efficiency and microalgal growth was more significant than that of sulfate concentration, while the interaction effect between sulfate and iron was not observed. The average ammonium removal efficiency (14 to 30%) and microalgal biomass con-centration (0.55 to 1.17 g particulate organic carbon per L) in continuous-flow mem-brane photobioreactor were promoted by adding a low concentration of zeolite (0.5 g L-1). The zeolite likely provided a habitat for attached growth of microalgae and high availability of ammonium for growth on the surface of the zeolite due to ammonium adsorption to zeolite. Further increase in zeolite concentration (from 0.5 to 1 and 5 g L-1) did not improve ammonium removal efficiency or biomass concentration. This was likely due to the increased solution turbidity caused by breaking apart of added zeolite particles into finer particles, which reduced light availability.In summary, this work showed the possibility of utilizing microalgae in wastewater treatment to efficiently remove nutrients and organic matter, and simultaneously pro-mote microalgal growth. Selecting suitable microalgal species for the specific wastewater to remove nutrients and organic matter is essential to promote algae-based wastewater treatment applications

Lake Victoria situated in East Africa faces an acute problem with eutrophication. Many reasons like agricultural production, industrialization, anthropogenic processes, the introduction of species, and economic activities have caused a stress to the overall well-being of the lake. Excess carbon, nitrogen, and phosphorus drive an increase in productivity which affects eutrophication. Previous studies on sediments and nutrient concentrations in the lake have concluded that nutrient concentrations increase due to release from the catchment. This study focuses on catchment sediments collected from four different sites and compares the results with sediments from two additional sites in the lake. The sediment core from Siaya indicates the highest concentrations of TOC (180 g/kg), TN (13 g/kg) and TP (17000μg/L). It is a rural site and poor agricultural practices such as the burn and slash, use of too many fertilizers, clearance of land, atmospheric deposition and precipitation increase elemental concentrations in the sediments compared to the more urban sites. In the lake sediments, the BILL core had higher concentrations of TP (430g/kg) and TN (16 g/kg) compared to the other site (LV-95) which is located far away from the margins of the lake. This core, however, had high TOC levels (180g/kg). The increase of nutrient levels in lake sediments is thought to be due to non-point sources from the catchment. Analyses of stable carbon isotope were used to infer the different organic matter source in the sediments. Based on the range of values for δ13C vs. C/N it is inferred that aquatic algal production and C4 vascular plants are the dominant sources for the organic matter input. The chemical characterization of catchment and lake sediments provides a qualitative link to nutrient influx and eutrophication in the lake.

No description available.

For decades the Baltic Sea has been subject to eutrophication due to heavy anthropogenic nutrient loads on the aquatic ecosystem. Quantitative projections of its effects require an understanding of its driving mechanisms, i.e., the hydrodynamics that are responsible for the physical transport and mixing and the biogeochemical nutrients pathways within the algal ecosystem and between the particulate and dissolved phases in the water and in the sediments. A simple basin-scale hydrodynamic framework is set for the Gulf of Finland to test different descriptions of the biogeochemical transformations and determine the most robust modelling strategy. A recently developed criterion to determine the occurrence of anoxic events, based on the amount of fresh carbon detritus in the sediments is implemented in comparison with the classical criterion based on the oxygen concentration in the bottom water. Time-averaging of the hydrodynamics over larger than daily intervals is proved to hinder the capture of rapid mixing events jeopardizing irremediably the water quality simulation. The new carbon based criterion for anoxia shows a better dynamic response and is less sensitive to the model’s internal parameters. An internal source in the sediments correlated to the amount of fresh detritus, to represent the release of iron-bound phosphorus is confirmed as a versatile modelling assumption.

The nutrients available in urine make it a good resource as fertilizer. Limited availability of natural phosphorus (P) is compelling people to think about recovering and returning it back to the land from waste stream. Urine comprising the majority of nitrogen (N) and P among other household wastewater, if managed separately, will benefit human against expensive commercial fertilizers, and eventually will reduce environmental problems. Various reactive filter systems have been studied since late 90’s as a potential system to recover N & P from urine and wastewater as a whole. Most studies are however limited to the laboratory scale only. Optimization of such technologies is one of the prime focuses in this area of research. This thesis project used the combination of two sorptive reactive materials, namely mordenite and polonite, to remove NH4-N and PO4-P from the source separated human urine. This two months laboratory scale study recommends dilution and storage to be a minimum pretreatment for urine. However as the influent’s NH4-N concentration was extremely high, further dilution or other relevant pretreatment is recommended. In overall, mordenite materials performed better for NH4-N removal reaching as high as 79% whereas polonite materials showed better results for PO4-P removal and the efficiency was as high as 97%. The reduction in NH4-N might also be due to the conversion of nitrogen into other forms. Mordenite materials showed a good potential for PO4-P removal and was up to 88% efficient initially. Both materials did not show the tendency of breakthrough for PO4-P until the end. The salinity measured as electric conductivity was reduced by both materials until about initial half-time period of the experiment. Since mordenite was the first unit to face the highly concentrated urine, it got saturated earlier and started showing the fluctuations in reduction and release for nutrients. The results obtained in this study provide the positive scenario for it to be implemented in the full scale system. However more elaborated studies in full scale addressing the major limitation of this project needs to be done before introducing the system for public uses.

Eutrophication is a major problem in the Baltic Sea and is the result mainly of the increase of the anthropogenic nutrient loading. Thus, the links among water quality, sediments, and eutrophication have to be understood in order to predict the consequences of our actions and of the climate change on the Baltic Sea. Therefore, water quality models that take into account the hydrodynamics have to be developed to help policy makers. In that perspective, the Kiirikki model, an ecosystem and sediment model, coupled to a box approach has been used to describe the water quality of the Baltic Sea. The latter has been divided into twelve sub-basins according to the topography, each of them separated into two vertical layers. The Kiirikki model has been implemented on each sub-basin and the hydrodynamics are used to link sub-basins between them. After calibration, it can be seen that the model results are consistent with the monitoring data for the southern part, even if the dissolved inorganic nitrogen levels are too high during the winter and some phase shifts are observed. For the northern part, the primary production is well modelled but there is an offset concerning the dissolved inorganic nutrient. Thus, it can be concluded that the implementation of the Kiirikki model is a realistic tool to describe the water quality and eutrophication of the Baltic Sea. However, the differences indicate that the Baltic Sea model cannot be use for policy making yet and more work is needed to improve the model such as a global sensitivity analysis as well as the use of site specific parameters.

Studiens syfte var att ta reda på vilka uppfattningar barn i åldern 4–6 har om olika näringsämnen i livsmedel. Dessutom att undersöka vilka ord de använder sig av när de beskriver detta samt vilka kopplingar de gör mellan olika livsmedels innehåll och roll i kroppen.  I studien har 11 barn från två olika förskolor intervjuats genom semistrukturerade kvalitativa intervjuer. Det sociokulturella perspektivet har använts då det är barns samtalande och uppfattningar som arbetets fokus riktats åt. I resultatet framkommer att barnen besitter olika uppfattningar kring vad livsmedel innehåller. De hade en relativt likvärdig syn på vilken roll livsmedlens innehåll har för roll i människokroppen. Flertalet av barnen kopplade livsmedel till hälsa och fysisk rörelse eller styrka, medan några få barn beskrev livsmedlets nedbrytning och omvandling på en översiktlig nivå. Barnen förklarade att många av de begrepp som specifikt berörde näringsämnen var helt okända sedan tidigare.  Studien ger en bild av barns uppfattningar om näringsämnen och dess roll i människokroppen. Studien kan också fungera som ett verktyg i förskolan för att planera undervisning inom ämnet. / The purpose of the study was to find out preschool children’s perceptions of food based on the main nutrients in the food, what words they use when describing this and what connections they make between food content and role in the human body.  In the study, 11 children from two different preschools were interviewed through semi structured qualitative interviews. The sociocultural perspective has been used because focus in the study was directed at children’s conversations and perceptions. The result shows that the children have different opinions about what foods contain. They had a relatively similar view of the function of food in the human body. Most children linked food to health and physical movement or strength, while a few children described the food’s degradation and transformation at a general level. The children explained that many of the concepts that specifically touched on nutrients were completely unknown since before. The study provides a picture of children’s perceptions of nutrients and their role in the human body and can serve as a tool in preschool to plan teaching on the subject.