Two decades of chemical imaging of solutes in sediments and soils:a review

AbstractThe increasing appreciation of the small-scale (sub-mm) heterogeneity of biogeochemical processes in sediments, wetlands and soils has led to the development of several methods for high-resolution two-dimensional imaging of solute distribution in porewaters. Over the past decades, localised sampling of solutes (diffusive equilibration in thin films, diffusive gradients in thin films) followed by planar luminescent sensors (planar optodes) have been used as analytical tools for studies on solute distribution and dynamics. These approaches have provided new conceptual and quantitative understanding of biogeochemical processes regulating the distribution of key elements and solutes including O2, CO2, pH, redox conditions as well as nutrient and contaminant ion species in structurally complex soils and sediments. Recently these methods have been applied in parallel or integrated as so-called sandwich sensors for multianalyte measurements. Here we review the capabilities and limitations of the chemical imaging methods that are currently at hand, using a number of case studies, and provide an outlook on potential future developments for two-dimensional solute imaging in soils and sediments

Spatiotemporal dynamics of phosphorus release, oxygen consumption and greenhouse gas emissions after localised soil amendment with organic fertilisers

AbstractOrganic fertilisation inevitably leads to heterogeneous distribution of organic matter and nutrients in soil, i.e. due to uneven surface spreading or inhomogeneous incorporation. The resulting localised hotspots of nutrient application will induce various biotic and abiotic nutrient turnover processes and fixation in the residuesphere, giving rise to distinct differences in nutrient availability, soil oxygen content and greenhouse gas (GHG) production. In this study we investigated the spatiotemporal dynamics of the reaction of manure solids and manure solids char with soil, focusing on their phosphorus (P) availability, as current emphasis on improving societal P efficiency through recycling waste or bio-based fertilisers necessitates a sound understanding of their behaviour. Soil layers amended at a constant P application rate with either pig manure solids or char made from pig manure solids were incubated for three weeks between layers of non-amended, P-depleted soil. Spatial and temporal changes in and around the amendment layers were simultaneously investigated in this study using a sandwich sensor consisting of a planar oxygen optode and multi-element diffusive gradients in thin films (DGT) gels, combined with GHG emission measurements. After three weeks of incubation, the soil containing a layer amended with manure solids had a lower overall O2 content and had emitted significantly more CO2 than the non-amended control or the char-amended soil. The P availability from manure solids was initially higher than that from the char, but decreased over time, whereas from the char-amended layer P availability increased in the same period. In both treatments, increases in P availability were confined to the amended soil layer and did not greatly affect P availability in the directly adjacent soil layers during the three-week incubation. These results highlight the importance of placing organic P fertilisers close to where the plant roots will grow in order to facilitate optimal fertiliser use efficiency

Assessing the phosphorus demand in European agricultural soils based on the Olsen method

Overcoming the consequences of future scarcity of P is crucial to ensure agriculture sustainability. This requires decision-making processes depending on data on the P status of agricultural fields, commonly conducted with soil P tests (SPTs), and efficient use of the resource on a societal scale following a circular economy approach. All this will decrease the P losses and the subsequent environmental impact. However, SPTs are not universal and, even for a given SPT, the definition of threshold values for fertilizer response is not accurate. This work aimed to define models to predict Olsen P threshold values, allowing the identification of P-responsive sites at the European scale as a basis for more accurate and sustainable P fertilization schemes based on a circular economy approach. To this end, a data set was compiled based on a literature review that describes the Olsen P threshold values for different crops under field conditions. Subsequently, an analysis of potential P fertilizer requirements was performed on agricultural soils of the European Union (EU) using the data set of the LUCAS project and how this need can be covered with a circular economy approach. Environmental factors were more relevant than crops to explain the variation in threshold values. A regression model involving soil pH and clay content and annual average rainfall as independent variables explained 61% of the variance in Olsen P threshold values. When soil pH and clay content were the only explanatory variables, the explained variance was 49%. This reveals the need to take into account factors related to P buffer and sorption capacity to estimate accurate threshold values. We detected that only 27.8% of EU cropland soils and 42.7% of grassland soils were P-responsive. We can conclude that a more precise allocation of the resource is possible in P-responsive sites and also that most of the European demand for P could be covered by recycling P from manure, wastewater, and municipal solid waste

Democracy in danger? : the role of policy advice and lobbyism in the EU-political system : a critical analysis of the public affairs debate

Durch die voranschreitende Globalisierung, die Mitgliedschaft 6sterreichs bei der Europ\ue4ischen Union und die daraus erfolgte Kompetenzverschiebung nach Br\ufcssel ist es naheliegend, Lobbyismus nicht nur auf nationaler, sondern auch auf der EU-Ebenen aus der Perspektive des politisch-demokratischen Systems zu untersuchen. Lobbyismus selbst geh\uf6rt zweifelsohne zum demokratischen Entscheidungsfindungsprozess, um die Interessen von B\ufcrgerInnen und Unternehmen zu b\ufcndeln und nach au fen hin zu vertreten. Sch\ue4tzungen zufolge werden mehr als die H\ue4lfte der Gesetze der 27 Mitgliedsstaaten in Br\ufcssel gemacht, die Zahl der LobbyistInnen in und um Br\ufcssel betr\ue4gt zwischen 15.000 und 20.000. Diese Arbeit hat das Ziel einen Beitrag zur Debatte \ufcber Public Affairs, Politikberatung und im Speziellen Lobbyismus auf europ\ue4ischer Ebene zu liefern. Dahingehend wird folgende Forschungsfrage beantwortet: Welche Rolle nimmt Lobbyismus im demokratischen Gesetzgebungsprozess der Europ\ue4ischen Union ein? Die Arbeit besteht aus zwei Teilen: Im ersten Teil wird versucht, die Forschungsfrage mit Hilfe einer Literaturrecherche zu beantworten. Im zweiten Teil werden die theoretisch erforschten Ergebnisse durch ein qualitatives halb-standardisiertes Leitfadeninterview erg\ue4nzt. Interviewt werden aktive und ehemalige \uf6sterreichische Abgeordnete des Europ\ue4ischen Parlaments, der Vizepr\ue4sident des Europ\ue4ischen Parlaments und ExpertInnen zum Thema Lobbyismus und Transparenz.Due to advancing globalization, Austria's membership in the European Union and the resulting shift of competences to Brussels, it\u2019s obvious to examine lobbying on the national and on the EU level from the perspective of the political-democratic system. Lobbying is undoubtedly part of the democratic decision-making process to bundle the interests of citizens and companies and represent them to the public. It\u2019s estimated that more than 50% of law-making of the 27 member states are made in Brussels. The number of lobbyists in and around Brussels is between 15,000 and 20,000. This thesis has the aim to contribute to the debate on public affairs, policy advice and lobbying at the European level. Based on this, the following research question will be answered: What is the role of lobbyism in the democratic legislative process of the European Union? The thesis consists of two parts. The first part is a literature review. The second part will complement the literature review with results by a qualitative semi-standardized guided interview. Active and former Austrian Members of the European Parliament, the Vice-President of the European Parliament and experts of lobbying and transparency were interviewed.Jakob SantnerAbweichender Titel laut cbersetzung des Verfassers/der VerfasserinMasterarbeit Karl-Franzens-Universit\ue4t Graz 202

Numerical Evaluation of Lateral Diffusion Inside Diffusive Gradients in Thin Films Samplers

Using numerical simulation of diffusion inside diffusive gradients in thin films (DGT) samplers, we show that the effect of lateral diffusion inside the sampler on the solute flux into the sampler is a nonlinear function of the diffusion layer thickness and the physical sampling window size. In contrast, earlier work concluded that this effect was constant irrespective of parameters of the sampler geometry. The flux increase caused by lateral diffusion inside the sampler was determined to be ∼8.8% for standard samplers, which is considerably lower than the previous estimate of ∼20%. Lateral diffusion is also propagated to the diffusive boundary layer (DBL), where it leads to a slightly stronger decrease in the mass uptake than suggested by the common 1D diffusion model that is applied for evaluating DGT results. We introduce a simple correction procedure for lateral diffusion and demonstrate how the effect of lateral diffusion on diffusion in the DBL can be accounted for. These corrections often result in better estimates of the DBL thickness (δ) and the DGT-measured concentration than earlier approaches and will contribute to more accurate concentration measurements in solute monitoring in waters

PROST: Parallel Robust Online Simple Tracking ∗

Tracking-by-detection is increasingly popular in order to tackle the visual tracking problem. Existing adaptive methods suffer from the drifting problem, since they rely on selfupdates of an on-line learning method. In contrast to previous work that tackled this problem by employing semisupervised or multiple-instance learning, we show that augmenting an on-line learning method with complementary tracking approaches can lead to more stable results. In particular, we use a simple template model as a nonadaptive and thus stable component, a novel optical-flowbased mean-shift tracker as highly adaptive element and an on-line random forest as moderately adaptive appearancebased learner. We combine these three trackers in a cascade. All of our components run on GPUs or similar multicore systems, which allows for real-time performance. We show the superiority of our system over current state-ofthe-art tracking methods in several experiments on publicly available data. 1