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Achieving urban water security is a major challenge for many countries. While several studies have assessed water security at a regional level, many studies have also emphasized the lack of assessment of water security and application of measures to achieve it at the urban level.
Recent studies that have focused on measuring urban water security are not holistic, and there is still no agreed-upon understanding of how to operationalize and identify an assessment framework to measure the current state and dynamics of water security. At present, there is also no clearly defined and widely endorsed definition of urban water security. To address this challenge, this study provides a systematic approach to better understand urban water security, with a working definition and an assessment framework to be applied in peri-urban and urban areas. The proposed working definition of urban water security is based on the United Nations (UN) sustainable development goal on water and sanitation and the human rights on water and sanitation. It captures issues of urban-level technical, environmental, and socio-economic indicators that emphasize credibility, legitimacy, and salience.
The assessment framework depends on four main dimensions to achieve urban water security: Drinking water and human beings, ecosystem, climate change and water-related hazards, and socio-economic factors (DECS). The framework further enables the analysis of relationships and trade-off between urbanization and water security, as well as between DECS indicators. Applying this framework will help governments, policy-makers, and water stakeholders to target scant resources more eff ectively and sustainably. The study reveals that achieving urban water security requires a holistic and integrated approach with collaborative stakeholders to provide a meaningful way to improve understanding and managing urban water security.
Life cycle assessment is a crucial tool in evaluating systems performances for sustainability and decision-making. This paper provided environmental impact of integrating renewable energy systems to the utility-grid based on a baseline optimized energy production data from “HOMER” for renewable systems modelling of a site in northern Nigeria. The ultimate goal was to ascertain the best hybrid option(s) in sustaining the environment. Different assumptions and scenarios were modelled and simulated using Ganzleitlichen Bilanz (GaBi). Uncertainty analysis was ensured to the impact data based on pedigree-matrix and Excel-program, as well as overall policy relevance. The results of the impact categories revealed first scenario (i.e., conventional path-based) with the highest impacts on global warming potential (GWP), acidification potential (AP), human toxicity potential (HTP), and abiotic depletion potential (ADP fossils). The lowest impacts arise in
the renewable-based scenarios for all the considered categories except the Ozone-layer depletion potential Category where the highest contribution falls in the third scenario (i.e., photovoltaic (PV)/biomass-biogas system) although all values being infinitesimal. In quantitative terms, the reduction in the GWP from the highest being the first scenario to the lowest being the fourth scenario (i.e., wind/biomass-biogas system) was 96.5%. Hence, with the outstanding contributions of the hybrid renewable systems, adopting them especially the lowest impact scenarios with expansions is relevant for environmental sustainability.
Before transporting the landfill leachate to municipal wastewater treatment plant it has to be treated in a landfill leachate treatment plant, as it comprises high concentrations of ammonium. The elimination of ammonium load in the leachate is usually done by the combined processes of nitrification and denitrification with a specially adapted biocenosis in the activated sludge (AS). For each of the steps, specialized bacteria such as Nitrosomonas, Nitrobacter and Paracoccus are used to transfer the ammonia to gaseous nitrogen. The aim of this investigation was to find suitable process parameters for a complementary treatment of fermentation water from a biogas plant together with landfill leachate. The processed water of the biogas plant consists of a higher concentration of ammonium and carbon sources or easily degradable volatile fatty acids. It can save the usage of external carbon source (acetic acid) and additionally it could also compensate the missing volumes of leachate in times of low rain and low leachate flows. To maintain the high workload for the existing leachate treatment pilot plant (LTPP), a combined treatment of landfill leachate and process water is also of economic and of ecological interest. The long-term adaption process of the biocenosis needs to be done step-by-step. Innovative process monitoring is needed to prevent biocenosis collapse. In our study, we present our set-up, a closer look at the ongoing experiment and the long-term changes in the biocenosis.
Modern industrial biomass combustion plants are regulated by the power and/or combustion control. In this process, the implemented sensors collect the relevant measured data. The aim is to achieve ideal combustion with optimum efficiency and to minimize gas emissions. For this purpose, a group within the research project Metabolon developed new regulatory procedures in order to record the combustion process of a biomass combustion plant using a webcam. The recordings were evaluated automatically and were used for a better monitoring of the process. In addition, the webcam-based method aims, among other things, to provide private homes with a cost-effective variant as an alternative to industrial system solutions.
This market research paper has been prepared under the supervision of Prof. Dr. Wolfgang Veit of TH Köln and Prof. Dr. Carol Scovotti of University of Wisconsin-Whitewater in the course of the inter-university cross-border collaboration student research project “Export Opportunity Surveys (EOS)”. This study explores organic lipstick export opportunities to the German and US markets.
Water shortage and a rising water demand are prevalent issues on the political agenda worldwide. Available water resources must not only be provided to ensure a domestic and drinking water supply for a steadily increasing population but also for the growing industrial and agricultural sectors. This work outlines how the use of the innovative vacuum multi‐effect membrane distillation contributes to improve the water management efficiency in the following key industry sectors: desalination, drinking water and beverage industry, pharmaceutical, agro and chemical as well as oil and gas industry.
The whole site of the waste disposal centre Leppe in Lindlar has been modified by the project :metabolon into an authentic learning site for knowledge transfer. Addressing all age groups, the project offers insights into environmental knowledge and explains contexts of resources and material flows. The site conditions allow practical outlooks on future energy systems. Following the meta theme of “lifetime learning”, pupils and students are addressed by different modules, considering their individual learning levels.
As the number and intensity of environmental challenges increase, more faiths have initiated religiously motivated change within their communities or have been involved in cooperation projects with NGOs or GOs dedicated to conservation. Even though a lot of quantitative research had been done on the correlation of religiosity and concern for the environment, no scientific study dealt about the argumentation lines that drive or discourage believers to get involved in environmental conversation. As a basis for the research the Theory of Planned Behavior of Ajzen was modified into a model. By the means of Semi-Standardized Interview guidelines 15 members and leaders of different church communities in Amman were interrogated to retrieve meaning of and cause-effect-chains between the different components of the model. Their answers were coded and analyzed with cross tables to identify interconnections and their tendencies.
The results show that interviewees’ religious convictions about God and the world were the strongest influencer, whereas the community and leaders rarely gave a reason for people to adapt water saving measures. External factors such as governmental, societal, political or economic mostly discouraged people to adapt environmentfriendly behaviors. Approaches by the GIZ have already started catering to those challenges and potentials, however the range of impact did not reach until most of the interviewees.
Web browsers use HTTP caches to reduce the amount of data to be transferred over the network and allow Web pages to load faster. Content such as scripts, images, and style sheets, which are static most of the time or shared across multiple websites, are stored and loaded locally when recurring requests ask for cached resources. This behaviour can be exploited if the cache is based on a naive implementation. This paper summarises possible attacks on the browser cache and shows through extensive experiments that even modern web browsers still do not provide enough safeguards to protect their users. Moreover, the available built-in as well as addable cache controls offer rather limited functionality in terms of protection and ease of use. Due to the volatile and inhomogeneous APIs for controlling the cache in modern browsers, the development of enhanced user-centric cache controls remains -until further notice- in the hands of browser manufacturers.
The quantification of greenhouse gas emissions from aquatic ecosystems requires knowledge about the spatial and temporal dynamics of free gas in sediments. Freezing the sediment in situ offers a promising method for obtaining gas‐bearing sediment samples, unaffected by changes in hydrostatic pressure and sample temperature during core withdrawal and subsequent analysis. This article presents a novel freeze coring technique to preserve the in situ stratigraphy and gas bubble characteristics. Nondestructive X‐ray computed tomography (CT) scans were used to identify and characterize coring disturbances of gravity and freeze cores associated with gassy sediment, as well as the effect of the freezing process on the gas bubble characteristics. Real‐time X‐ray CT scans were conducted to visualize the progression of the freezing process. Additional experiments were conducted to determine the freezing rate to assess the probability of sediment particle/bubble migration, and gas bubble nucleation at the phase transition of pore water to ice. The performance of the freeze coring technique was evaluated under field conditions in Olsberg and Urft Reservoir (Germany). The results demonstrate the capability of the freeze coring technique for the preservation of gas‐bearing sediments and the analysis of gas bubble distribution pattern in both reservoirs. Nevertheless, the obtained cores showed that nearly all gravity and freeze cores show some degree of coring disturbances.
The electricity network is undergoing a change due to reducing costs for renewable energy sources. Subsidy programs for renewable energy sources are changing and the funding available is being reduced. This will have an impact on anaerobic digestion which in some cases may struggle financially. Overfeeding is one of the most common mechanisms of inhibition in the process, and by shifting to intermittent feeding for on-demand production, this change will provide more information about the digestion process and could be used to detect the beginning of inhibition due to overfeeding. This paper discusses the shift towards intermittent production and how this change can be used to monitor the anaerobic digestion process.
REST became the go to approach when it comes to large scale distributed systems on, or outside the World Wide Web. This paper aims to give a brief overview of what REST is and what its main draws and benefits are. Secondly, I will showcase the implementation of REST using HTTP and why this approach became as popular as it is today. Based on my research I concluded that REST’s advantages in scalability, coupling, performance and its seamless integration with HTTP enabled it to rightfully overtake classic RPC based approaches.
Soils are complex, evolving systems that simultaneously shape and are shaped by numerous biotic and abiotic factors in a vast web of interactions that creates the conditions for the propagation of life and the maintenance of human societies. Yet, land use and land use change (LULUC) and anthropogenic climate change (CC) are forcing substantial and rapid alterations into soil’s properties and processes, thus affecting the functions and services derived from it. The resulting land degradation (LD) is now spread, according to recent estimates, over nearly 30 % of the world’s total land, mostly on the population dense and impoverished tropics, a zone predicted to withstand the worst impacts of CC. The Atlantic Forest in Brazil is a particularly vulnerable environment, and the unusual drought of 2014-2017 that hit its Southeastern region is likely the harbinger of a progressively drier future.
The way the prelude of what might be an increasingly frequent hazard affected farmers’ livelihoods and natural resources, and the manner in which they reacted to those impacts can thus reveal points of strength and fragility that could be respectively harnessed or addressed to develop a more sustainable agriculture and climate resilience. This master thesis focused on characterizing those impacts and reactions on distinct dairy production systems in two municipalities in Northwestern Rio de Janeiro: Santo Antônio de Pádua and Cambuci. Through interviews and in loci observations, the researcher collected data concerning environmental services (erosion prevention, soil cover and water provision), production variables (inputs and outputs), socio-economic information, farm system management and farmers’ future perspectives. The results show that dairy production systems in the region are heterogeneous and, although they may share common characteristics, drought outcomes were closely tied to the specificities of each farm. Ultimately, outcomes originated from differences in water supply, water demand, and feed availability, their subsequent change by the drought and farmers’ reaction to those changes at each property.
Resilience in relation to flood risk management (FRM) is not a new concept, yet parts of the FRM community are still struggling to apply it. The main challenge this study addresses is the question as to whether parts of the FRM community should still adopt, or rather “leap‐frog,” resilience. The main purpose is to evaluate whether resilience is a still on‐going trend or, already subsiding. Research suggests that resilience is an on‐going trend that connects research and policy and has gained international recognition as expressed by international guidelines and bodies promoting its research but also its operationalization. Academic literature in the area of FRM also shows a significant continuing development. Resilience enables to analyze dynamics and transformations of riverine areas, or coastal zones in connection to an integrated social‐environmental system approach with more emphasis and conceptual basis than previous concepts. Resilience is more than a short‐lived notion and it appears that FRM researchers cannot avoid addressing it. Resilience often is a convergence of ideas and mainstreaming of efforts, which in many venues is absolutely necessary and can help, for example, to decrease silo‐thinking. But as academics, we have a mandate to remain skeptical and remain on the look‐out for novel ideas, too.
This article is categorized under:
Engineering Water > Planning Water
While global food production greatly exceeds dietary energy demand, undernutrition remains, and diets largely fail to ensure the health of the population. Agricultural biodiversity is crucial for the world’s food security, but genetic diversity has been degraded. In Mexico, the dietary transition towards processed foods has contributed to malnutrition and a rise of diet-related chronic diseases. Mexico’s indigenous people are conserving and creating valuable plant genetic resources in their swidden milpas and traditional agroforestry systems but remain the country’s most vulnerable population group. The Teenek (or Huastec), an indigenous group that habitat the Huasteca Potosina, a region in north-eastern Mexico cultivate a high diversity of edible plants in their home gardens (solar), milpas, and agroforestry systems (te’lom, or finca). However, migration has been leading to the abandonment of traditional farming in the region.
The objective of this study was to analyse if the managed agricultural biodiversity of the different traditional land use systems contributes to the food security of the farming households in the community of Jol Mom. Food availability and access were investigated. In total, 40 households were surveyed. Dietary patterns were identified through principal component analysis. Informal interviews, semi-structured interviews and participant observation allowed to account for the people’s own perceptions and provided additional insights. Findings showed that traditional Teenek farming systems are the source of a variety of nutritious foods and resulted to be the most important provider of fruits and vegetables. The average production diversity was 34 out of 56 crops, farmers cultivating more than one or two farming systems showed an increase of four and 11 produced species respectively. Production diversity was strongly correlated with food variety in a household’s diet, with an increment of one per 0.85 produced crop. Two main diverging dietary patterns were revealed, a westernized diet relying largely on purchased foods, to which the younger generation was more inclined, and a traditional diet characterized by a high consumption of cultivated products, mostly observed in the older households.
In conclusion, farming households in Jol Mom profit from the agricultural diversity of their production systems, either through the consumption of nutritious foods or by the sale of agricultural products. However, a tendency towards nutrient-poor diets was observed. Increasing agricultural diversity and consumption of locally produced foods might help to fight this trend but would require a valorisation of traditional foods and an appreciation of the contribution of indigenous people’s traditional agriculture to food security.
Metallic tubular micro-components play an important role in a broad range of products,
from industrial microsystem technology, such as medical engineering, electronics and optoelectronics, to sensor technology or microfluidics. The demand for such components is increasing, and forming processes can present a number of advantages for industrial manufacturing. These include, for example, a high productivity, enhanced shaping possibilities, applicability of a wide spectrum of materials and the possibility to produce parts with a high stiffness and strength. However, certain difficulties arise as a result of scaling down conventional tube forming processes to the microscale. These include not only the influence of the known size effects on material and friction behavior, but also constraints in the feasible miniaturization of forming tools. Extensive research work has been conducted over the past few years on micro-tube forming techniques, which deal with the development of novel and optimized processes, to counteract these restrictions. This paper reviews the relevant advances in micro-tube fabrication and shaping. A particular focus is enhancement in forming possibilities, accuracy and obtained component characteristics, presented in the reviewed research work. Furthermore, achievements in severe plastic deformation for micro-tube generation and in micro-tube testing methods are discussed.
The introduction of Feed-in tariffs in the German Renewable Energy Act (EEG) fuelled the growth of anaerobic digestion (AD) industry making Germany the country with highest number of operational AD plants. However, the rapid expansion of AD industry resulted in some unwanted side-effects such as food vs fuel debate, increased prices for electricity and the temporal mismatch between supply and demand of electricity grid. Subsequent amendments in EEG has tried to address some of these issues by reduction in Feed-in tariffs, introduction of a cap on cereal based feedstocks and providing premium for energy production in accordance with market demand. Furthermore, the Feed-in tariffs which were introduced for 20 years are soon going to expire. The changes in legal and political discourse is soon going to introduce some new challanges to the AD industry. This paper has discussed some of these challanges and their potential solutions.
Pseudozyma antarctica Lipase B catalyzed esterification and transesterification in deep eutectic solvents (DES) was investigated in reaction systems with alcohols of different polarity. Coconut oil and crude biodiesel were deacidified successfully with non-immobilized CALBL and final acid values of 1.2 for biodiesel and 0.5 for coconut oil were obtained, while no esterification with ethanol was observed without DES. Water depletion of the lipid phase in the presence of water adsorbing DES causes this difference. Analysis of water contents revealed a 10 fold lower water content of the lipid phase in the presence of a second DES phase than in trials without utilization of DES. In contrast reactions of hydrophilic polyols are suppressed in the presence of DES. While the esterification of fructose and the transesterification with glycerol worked well in the polar solvent 2-methyl-2-butanol, almost no fructose esterification and a decreased transesterification with glycerol were observed in the presence of DES. Analysis of logP values of the substrates explains the substrate dependent differences in reactivity. The polar alcohols are probably bound strongly in the hydrogen-bonding network of the DES phase and are thus not available for lipase catalyzed reactions.
Sensors can monitor physical attributes and record multimodal data in order to provide feedback. The application calligraphy trainer, exploits these affordances in the context of handwriting learning. It records the expert’s handwriting performance to compute an expert model. The application then uses the expert model to provide guidance and feedback to the learners.
However, new learners can be overwhelmed by the feedback as handwriting learning is a tedious task. This paper presents the pilot study done with the calligraphy trainer to evaluate the mental effort induced by various types of feedback provided by the application. Ten participants, five in the control group and five in the treatment group, who were Ph.D. students in the technology-enhanced learning domain, took part in the study. The participants used the application to learn three characters from the Devanagari script. The results show higher mental effort in the treatment group when all types of feedback are provided simultaneously. The mental efforts for individual feedback were similar to the control group. In conclusion, the feedback provided by the calligraphy trainer does not impose high mental effort and, therefore, the design considerations of the calligraphy trainer can be insightful for multimodal feedback designers.
In the last few decades raw material molasses, used in large scale fermentations in the production of bioethanol, citric acid, (baker´s) yeast and yeast extracts, has become more and more expensive. That is why agro-industrial wastes have become an interesting alternative. They are being produced in large volumes every day and represent a serious environmental problem considering its high organic content. The present contribution aims to demonstrate how waste products of wine production can be employed as substrate in bioethanol production. Cultivation of yeast and bioethanol production on molasses and grape pomace extract was studied in flasks in laboratory scale. This work should be regarded as an example of integrated sustainability which demonstrates how the waste from one industrial process is used as feedstock for another.