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- Fakultät 12 / Institut für Technologie und Ressourcenmanagement in den Tropen und Subtropen (17) (remove)
Changing our unsustainable linear water management pattern is necessary to face growing global water challenges. This article proposes an integrated framework to analyse and understand the role of different contextual conditions in the possible transition towards water circularity. Our framework combines a systematic multi-level perspective to explore the water system and the institutional work theory for technology legitimation. The framework consists of the following stages: (1) describing and understanding the water context, (2) assessment of the selected technologies’ circularity level, (3) assessment of the alternative circular technologies’ legitimacy, and (4) identification of the legitimation actions to support the upscale of alternative circular technologies. The practical applicability of the integrated assessment framework and its four assessment stages was demonstrated in the exploration of circular water technologies for the horticulture sector in Westland, the Netherlands. The results revealed the conditions that hinder or enable the legitimation of the circular water technologies, such as political environmentalism, trust in water governing authorities, and technical, financial, and knowledge capabilities.
Decisions on irrigation water management are usually made at different levels, including farms, water user associations (WUAs), and regional water planning agencies. The latter generally have good access to information and decision tools regarding water resources management. However, these remain out of reach to the final water users, namely the farmers. The study, conducted in the irrigated district of Cherfech, north Tunisia, had the main objective of investigating farmer’s perceptions of, and acceptance for, the use of an irrigation advisory service (IAS) to be implemented by their WUA. The suggested IAS provides the following information: (1) reference evapotranspiration (ETo) and rainfall; (2) crop water requirement (CWR) of the most cultivated crops; (3) irrigation water requirement (IWR) of the farmer’s crop; and (4) crop monitoring and real-time estimation of IWR of crops settled, using soil moisture sensors. Such services and information would be available at the WUA level and provided in a timely manner to farmers for more effective decision making at the plot level. Prior to the acceptance study, we launched a technical study to determine the required tools and equipment required for the implementation of the IAS, followed by a farmer survey to assess their respective perceptions and acceptance towards this IAS. Results showed that only 54% of the farmers are satisfied by WUAs work, but that 77% of them accepted using the suggested IAS. Farmers are also willing to pay for most of the IAS packages suggested. The financial profitability of investing in the IAS at the WUA level shows the venture is financially viable, with a benefit cost ratio (BCR) of 1.018. The project will be even more profitable if we add the social benefits, which may result in water savings at the WUA level.
Effects on the combustion properties of wheat straw after different thermobiological pretreatments
(2022)
Wheat straw could be used for pellet production and therefore as solid fuel. However, it presents challenges due to its inferior combustion properties such as high ash content, low gross calorific value (GCV), and low ash melting temperature.
To evaluate its combustion properties and based on recent work that improved methane production, wheat straw was subjected to thermobiological pretreatments. Nine pretreated samples based on wheat straw and nine pretreated samples based on compost-wheat straw mixture were produced. In addition, due to the ability to remove minerals and decrease the ash content, a washing process with water as a solvent was used. Ash content, net calorific value (NCV) and ash melting temperatures were evaluated.
For the pretreated wheat straw (SW) samples, a 5,8% reduction in ash content was obtained due to the pretreatments when compared to untreated wheat straw. A 55% decrease in ash content was obtained when comparing the same materials before and after the washing process. No statistically significant changes in GCV were found. As for the ash melting temperatures, due to the incubation pretreatment, an average increase in the shrinkage starting temperature (SST) of 4,4% was obtained for anaerobic conditions and a decrease of 2,5% for aerobic conditions, compared to the same material without heat treatment. In addition, an increase in all ash melting temperatures was observed because of the washing process. It was possible to obtain a pellet complying with standard ISO 17225-6 that can be used in medium or large burners and significantly reduces the effort during combustion.
For samples pretreated with a homogeneous compost-wheat straw (SKW) mixture, an average ash content decrease of 27% was obtained after using autoclave pretreatment at 140°C, compared to the same material without thermal pretreatment. The biggest decrease was due to the washing process, reducing the ash content on average by 43% when comparing the same materials before and after washing. GCV were 13% lower than samples pretreated with wheat straw, due to the low calorific value and high ash content of the compost. During ash melting temperature tests, an average 60% increase in SST was observed compared to pretreated SW ashes due to the high melting temperature of compost. Results are considered satisfactory since pellets based on this mixture would not cause ash sintering or slagging. However, counter effects were observed as the addition of compost increased the ash content and decreased the GCV, not complying with ISO 17225-6 for non-woody pellets. To achieve a pellet based on a compost-wheat straw mixture that complies with the standards, it is recommended for future research to control the percentage of compost added to the mixture.
AbstractThe Ganges-Brahmaputra (GB) delta is one of the most disaster-prone areas in the world due to a combination of high population density and exposure to tropical cyclones, floods, salinity intrusion and other hazards. Due to the complexity of natural deltaic processes and human influence on these processes, structural solutions like embankments are inadequate on their own for effective hazard mitigation. This article examines nature-based solutions (NbSs) as a complementary or alternative approach to managing hazards in the GB delta. We investigate the potential of NbS as a complementary and sustainable method for mitigating the impacts of coastal disaster risks, mainly cyclones and flooding. Using the emerging framework of NbS principles, we evaluate three existing approaches: tidal river management, mangrove afforestation, and oyster reef cultivation, all of which are actively being used to help reduce the impacts of coastal hazards. We also identify major challenges (socioeconomic, biophysical, governance and policy) that need to be overcome to allow broader application of the existing approaches by incorporating the NbS principles. In addition to addressing GB delta-specific challenges, our findings provide more widely applicable insights into the challenges of implementing NbS in deltaic environments globally.
Based on the idea of sustainable development, the BioTrade principles and criteria (P&C), based on the idea of sustainable development, have been the essential core guiding the implementation of BioTrade activities since their inception by UNCTAD in 2007. However, after identifying that BioTrade of medicinal plants causes negative impacts on the traditional knowledge related to these plants, the P&C were evaluated in light of the most relevant international agreements that contribute to the safeguarding of this knowledge. The result obtained from the assessment showed that the P&C present many gaps that prevent evaluating the real impact of trade on the traditional knowledge of medicinal plants in Indigenous and local communities. Therefore, in the same framework of the current P&C, the main recommendations contained in the international agreements and the suggestions of specialists in the field have been gathered to create a BioTrade standard that contributes to safeguarding traditional medicinal plant knowledge within a commercial context in any BioTrade initiative where the commercialized product is a sacred or native plant with traditional and cultural value for a community.
In the literature, many studies outline the advantages of agrivoltaic (APV) systems from different viewpoints: optimized land use, productivity gain in both the energy and water sector, economic benefits, etc. A holistic analysis of an APV system is needed to understand its full advantages. For this purpose, a case study farm size of 0.15 ha has been chosen as a reference farm at a village in Niger, West Africa. Altogether four farming cases are considered. They are traditional rain-fed, irrigated with diesel-powered pumps, irrigated with solar pumps, and the APV system. The APV system is further analyzed under two scenarios: benefits to investors and combined benefits to investors and farmers. An economic feasibility analysis model is developed. Different economic indicators are used to present the results: gross margin, farm profit, benefit-cost ratio, and net present value (NPV). All the economic indicators obtained for the solar-powered irrigation system were positive, whereas all those for the diesel-powered system were negative. Additionally, the diesel system will emit annually about 4005 kg CO2 to irrigate the chosen reference farm. The land equivalent ratio (LER) was obtained at 1.33 and 1.13 for two cases of shading-induced yield loss excluded and included, respectively.
This investigation attempts to understand the eco‐hydrology of, and accordingly suggest an option to manage floodwater for agriculture in, the understudied and data‐sparse ephemeral Baraka River Basin within the hyper‐arid region of Sudan. Reference is made to the major feature of the basin, that is, the Toker Delta spate irrigation scheme. A point‐to‐pixel comparison of gridded and ground‐based data sets is performed to enhance the estimates of rainfall. Analysis of remotely sensed land use/cover data is performed. The results show a significant reduction of the grassland and barren areas explained by a significant expansion of the cropland and open shrubland (invasive mesquite trees) areas in the delta. The cotton sown area is highly dependent on the flooded area and the discharge volume in the delta. However, the area of this major crop has declined since the early 1990s in favour of cultivation of more profitable food crops. Expansion of mesquite in the delta is problematic, taking hold under increased floodwater, and can only be manged by clearance to provide crop cultivation area. There is a great potential for floodwater harvesting during the rainfall season (June to September). A total seasonal runoff volume of around 4.6 and 10.8 billion cubic metres is estimated at 90 and 50% probabilities of exceedance (reliabilities), respectively. Rather than leaving the runoff generated from rainfall events to pass to the Red Sea or be consumed by mesquite trees, a location for runoff harvesting structure in a highly suitable area is proposed. Such a structure will support any policy shifts towards planning and managing the basin water resources for use in irrigating the agricultural scheme.
The ‘Energy Crisis’ has become the talk of the town in pretty much every developing and lower developing countries in today’s world. It is characterized by a state where the country’s locally available energy resources are being depleted and it is dependent on imported fuel. The problem is considered as although not parallel, but a descendant of the food crisis in terms of the seriousness of the problems in developing nations essentially in Sub-Saharan Africa (SSA). Ethiopia is one such country which nevertheless going through a rapid scale of development (nearly 11 % annual growth rate as of 2017 according to the World Bank) and also is endowed with an enormous amount of natural resources such as hydro, wind, solar, geothermal energy potential. The Ethiopian power sector is heavily dependent on the country’s hydropower resources. However, it needs to diversify its energy sector and integrate new and other renewable energy sources because, in the longer term, its extreme hydropower dependence may put its power sector vulnerable to natural risks like droughts which are very likely scenarios due to the climate change. Since the lack of access to modern forms of energy services left no choice for the Ethiopians than to continue their traditional biomass use, and it results in unsustainable environmental harm with deforestation, soil erosion, and many others. To address this issue, Ethiopia is taking necessary steps towards climate-friendly industrialization of the economy.
In order to understand this transition, a socio-technical analysis of Ethiopian ambitious transformation from an agrarian society to a climate resilient green society has been presented in this paper. An analytical framework will be formulated as a prerequisite for the study by introducing the theory of Multilevel Perspective (MLP). This theory enables the understanding of three different levels of socio-technical environment namely niches, regime, and landscape in which the respective actors interact with each other to facilitate the process of transition. As a part of laying the groundwork, this thorough analysis constitutes all the country’s energy-related activities and associated energy demands, conversion technologies, current fuel mix, primary energy resources, and energy policies in the Ethiopian energy system. The LEAP analysis results from Mr. Md Alam Mondal and group are summarized to obtain an understanding of the country’s total energy demand scenarios.
Consequently, the actors from each socio-technical level have been identified in the context of Ethiopia and their dynamics of interaction have been explained in order to understand the process of energy system transition of Ethiopia in the direction of diversification of its energy system and hence result in the expansion of new renewable energy sector. Most importantly the assessment suggests that the transition process is majorly driven by top-down forces and intra-level reconfiguration of regime actors. There are no bottom-up forces acting as only a little research and development work takes place in the country to develop new radical changes/technological niches. A developing country like Ethiopia has undoubtedly a bright future ahead with all systems in place and the nature-gifted natural resource potential. The ambitious goals set by the country and the international help from developed allies are definitely working in tandem to ensure their accomplishment. With its guiding vision towards development and the global climate change movement, Ethiopia surely has the potential to lead by example.
This project is focused on the generation of hardware independent code for PLCs and the comparison for energy consumption patterns of hydraulic and electric drive unit. This works is dedicated to MLC (mould level control) in a continuous casting machine, which is used to cast steel slabs continuously. The code generation is done with the help of the PLC coder which is present in the software Simulink. The programming is done entirely in MATLAB. The application of the generated code is tested on the Siemens S7-1500 PLC. For executing the code and the development of the HMI (human machine
interface) Siemens software TIA Portal V15 has been used. Moreover, for further analysis of signals and testing the code, a PDA or process data acquisition system, IBA system is used. For energy analysis also the IBA system is used.
Water is an eminently important element for societal development. It must be available in sufficient quantity and quality to meet human requirements of consumption, food production and sanitation. The riverine ecosystems are increasingly deteriorated due to human interventions. This leads to changes in the natural flow patterns. The concept of environmental flow started to emerge. Due to the importance of environmental flow in the integrated river basin management, researchers and scientists worldwide have made great efforts towards assessing the environmental flow requirements in river ecosystems. Various tools and techniques were defined. Governmental authorities and water ministries (all over the world including Egypt) have introduced regulations and policies to assure the vitality of environmental flow in river management and water allocation too.
Although different methods are available for the environmental flow assessment, those techniques are not practically applied. Implementing the environmental flow in real world is a challenge, due to the lack of political will and the stakeholder support, the institutional barriers and conflicts of interest, and finally the insufficient resources and capacity in environmental management institutions. It is a multidisciplinary and intersectoral process.
The present study aims to report the importance of environmental flow regarding the inhabitants’ daily life as well as the overall Egyptian socio-economic, political and health status. It demonstrates the methods of applying the Environmental flow concept in Egypt with a focus on social and political aspects, detailing the current situation in Egypt, and clarifying the obstacles that face the implementation process. The data was collected via local people questionnaires, stakeholders’ interviews and field visits. The study proposes solutions to evade the environmental flow implementation obstacles and overcome current challenges. Moreover, the study predicts future issues and offers solutions to avoid their occurrence.
For sustainable climate, an exponential growth in renewable heating and cooling is compulsory to reduce consumption of the fossil fuels for production of heat. An essential step from European Commission as an introduction of the strategy for renewable heat has
given a platform to the solar thermal market to tap the highest possible potential. To grab the opportunity given, capacity of the production is to be increased as well as reduction in cost of solar thermal product is to be achieved by any suitable alternate means. Polymer
based hybrid collector, named as OPVT collector, is the innovation from Fraunhofer Institute of Solar Energy Systems to break the road blocks for the solar thermal market. A polymer solar cell and a polymer solar thermal collector, both, technologies have tendency
of high initial investments and extremely low running cost in business. The aims of this study were to develop a calculation tool for determination of production cost of different OPVT collector concepts and evaluate their potential with reference to market size. The tool was expected to be uniform for all possible concepts of OPVT collector and flexible in
usage during the early stage of technological development. In this study, “Microsoft Excel” software based calculation tool is developed for estimation of production cost for different concepts. A Car washing station for water based OPVT collector and a bus station for air based OPVT collector are found be most suitable for start-up of the business. The analysis of results has highlighted that the minimum cost of OPVT collector can be referenced as its material cost. The OPVT collector business has huge potential and
possibility of early break-even point in the
production. As production costs are sensitive to
material costs, input values to the tool must be accurate. Presence of dominance of the material cost
is due to high cost of OPV. In industry, OPV is still being considered as the technological product instead the commodity product. This market potential study for
OPVT collector technology has been the important step in giving the confidence to solar thermal, polymer and plastic processing industries for business investment.
Keywords – OPVT collector, production cost, calculation tool, market size
Development of renewable energy projects within photovoltaic energy sector has reached unrestrainable pace in recent years and thus the investors are more vigilantly considering the further business deployment towards this sector. Underpinned with clear support from KfW Development Bank, the company MACS Energy & Water GmbH decided to facilitate future verification of credit lines towards these projects by deploying special eSaveTM software which would include technical and financial appraisals specially designed for their clients. Hereof this thesis comprises the initial phase development of this software within the MS Excel and endeavors to provide a proper guideline for the software engineers included in this task in the company. In order to simplify the explanation process this report sticks to 50 kW power plant project in Prokuplje. It is anticipated that this model would enhance, improve and expedite the feasibility analysis between the cooperatives by delivering the projections of energy yield, payback periods and sensitivity analysis of the loan conditions specified for the target country and PV projects in the same. However, besides this main task this report aims to fulfill all the other necessary prerequisites for accomplishing a good due diligence practice. Therefore the thesis places its focus to Republic of Serbia where exceptional due diligence reports were made, among which the Prokuplje project, and compiles the assessments in terms of legal, environmental and risk into one general framework for PV projects in this country. By doing so, the desktop-based model and results obtained with this user-friendly tool can lean on the full due diligence assessment and provide the reader a clear comprehensive overview of possibility to invest into this renewable energy sector in Republic of Serbia.
Keywords: PV, Due diligence, Serbia, eSaveTM, feasibility, model
Jordan is deemed as one of the least water-endowed regions in the world. The acute water shortage, accompanied with changing climatic conditions have necessitated the increasing use of treated wastewater (TWW), predominantly in irrigated agriculture sector. This is especially true with the upper Zarqa River. The ample supply of TWW resources can be found there; paradoxically, the practical implementation of TWW reuse is hindered by the enforcement of irrigation water quality standard, compounding pressure on the dwindling groundwater resources. In light of the large potential source of TWW, this study aims to supply knowledge on maximizing the safe reuse of TWW while minimizing the environmental impacts within the local environment of the upper Zarqa River. A SWOT analysis was conducted to identify the strengths, weaknesses, opportunities, and threats of TWW reuse for agriculture in the local context. In recognition of the projected growth in the treated effluent to more than 135 MCM in the coming ten years, and how it would affect the water use on the study region, several plausible development scenarios were proposed based on expected developments on the ground. Considering the vital role of TWW in sustaining multiple ecosystem services, this study addresses the need to review current standard, encourages managed aquifer recharge with TWW, recommends crops type modification, and enhances knowledge on suitable practices at farm level. Each of these factors is needed in order to deliver a range of ecosystem services to sustain the local rural communities and to advance them in the face of profound challenges, thereby leading to its stability and increased productivity.
Zusammenfassung
Ansatz der vorliegenden Arbeit ist es, mit Blick auf den in einer großen Variationsbreite existierenden Brauprozess in Brauereien mit unterschiedlichster jährlicher Produktionsmenge und technologischem Stand, die wesentlichen charakteristischen Teilprozessschritte hinsichtlich Ihrer Bedarfe an den thermischen Energieformen Wärme und Kälte, unter Berücksichtigung der jeweils in den Teilprozessen herrschenden Temperaturniveaus, darzustellen. Dies ist in Kapitel 2 sowohl für die in Trocknungsprozessen vorbehandelten feststofflichen Braukomponente Gerstenmalz und Hopfen, sowie für die mit dem Beginn der Erwärmung von frischem Brauwasser startenden Prozesse des Einmaischens, Läuterns, Kochens, Gärens bis hin zur Reifung des Jungbieres, erfolgt. Zunächst wurde das jeweilige Temperaturniveau der einzelnen Phasen des Brauvorgangs, trotz seiner unterschiedlichen verfahrenstechnischen Realisierung, abgesteckt. In Kapitel 5 wird der rein für den Prozess notwendige Wärme- und Kältebedarf, auf der Basis der wesentlichen Zustandsänderungen des entstehenden Produktes, bestimmt. Dabei liegt bei jedem Prozessschritt entweder ein Wärme- oder ein Kältebedarf vor. Die Teilprozesse bilden eine zeitliche Abfolge innerhalb des Brauprozesses, welche die Vorstufen des Bieres nacheinander durchläuft. Die in den Kapiteln 3 zum Thema Kälte und in Kapitel 4 zum Thema Wärme dargestellten Grundlagen, liefern die Grundlagen für das Verständnis, des Verhaltens eines Systems im Umfeld von thermischer Energie und bilden die thermodynamischen Kenntnisse, die für die Beurteilung des Transportes, der Erzeugung und der Speicherung von Wärme und Kälte ergeben. Die Wärme und Kältebedarfe in ihrer zeitlichen Abfolge ermöglichen uns unabhängig von gängigen technischen Realisierungen in der Praxis noch einmal in Kapitel 6 die Frage zu stellen, in wie weit zunächst für jeden einzelnen Teilprozess Energieeffizienzverbesserungen durch Eingriff in den Prozess möglich sind. Die Frage der Heranführung der Wärme bei Wärmebedarf des Produktes an das Produkt hat in der Entwicklung der Brauereitechnologie sehr verschiedenen konstruktiven Ausführungen der Maischgefäße und der Gefäße für die Würzebehandlung geführt. An dieser Stelle ist der Einfluss von Veränderungen, welche den Transport von Wärme verbessern könnten, auch auf das Produkt zu hinterfragen. Die modernen Ausführungen der Maisch- und Würzepfannen sind auf ein produktschonendes Verfahren ausgelegt. Änderungen im Anlagenpark erfordern von jeder Brauerei einen langerprobten Umgang, um trotz der Veränderungen an diesen Prozesshilfsmitteln, dennoch die geschmackliche Qualität des Bieres nicht unerwünscht zu beeinflussen. Die Rückführung der Verdampfungswärme beim Kochen und teilweise Verdampfen der Würze in der Pfanne, in den Prozess, unter Beibehaltung des höchstmöglichen Temperaturniveaus dieser Wärme, ist ein Beispiel aus Kapitel 6 für die Effizienzsteigerung des Teilprozesses. Stärker in den produktbeeinflussenden Teilprozess des Maischens greift die Wahl zwischen den zwei etablierten Wärmezufuhrverfahren, dem traditionellen Dekoktionsverfahren und dem in letzter Zeit deutlich überwiegenden Infusionsverfahren. Hier liegt mit der Wahl des letzteren Verfahrens, innerhalb des Teilprozesses Maischen ein Effizienzsteigerungspotential in der Praxis.
Die teilprozessübergreifende Kopplung der einzelnen Verfahrensschritte erlaubt den Transport von Wärme und Kälte, zwischen diesen Teilprozessen, unter Berücksichtigung der zeitlichen Versetzung der einzelnen Teilprozesse. Damit lassen sich Wärme- und Kältebedarfe untereinander bedienen, wenn eine Speichervorrichtung für Wärme auf den jeweiligen Temperaturniveaus vorhanden ist. Das Temperaturniveau der thermischen Energien ist, wie bereits in der Theorie in den Kapitel 3 und 4 gesehen, wo großer Bedeutung. Denn es geht bei der Steigerung der Energieeffizienz des Gesamtprozesses um die Erhaltung des Potentials der Wärme und Kälte trotz naturbedingter Einbußen, welche die Übertragung der Wärme aufgrund eines notwendigen Temperaturgefälles mit sich bringt. Die Kopplung der Teilprozesse entlang des Brauprozesses führt nach der Analyse in Kapitel 6 dazu, dass Energiezufuhr von außen am heißesten Ort entlang der Prozesskette erforderlich ist, da an dieser Stelle des Würzekochens und Verdampfens innerhalb des Gesamtprozesses keine Wärme auf diesem Temperaturniveau „ausgeliehen“ werden kann. Als Resultat erhält man, das eine Dampferzeugung zur Wärmebereitstellung mit einer Temperatur oberhalb der Siedetemperatur von 100°C erforderlich ist, sowie Kältebereitstellung für die kühlen Prozessschritte Gären und Reifen, bei denen die Aufrechterhaltung einer Temperatur bei knapp 0°C gegenüber der wärmeren Umgebung über eine längere Zeitdauer erforderlich ist.
Hiermit kommt man zu der zweiten Fragestellung aus der Einleitung, welche Szenarien der Bereitstellung der Energie, ggf. in Form einer Selbstversorgung der Brauerei sinnvoll ist.
Energetisch ist die Erzeugung von Wärme auf einem vergleichsweise moderaten Temperaturniveau von benötigten 120 bis 140°C durch die Verbrennung des Primärenergieträgers Erdgas im Dampferzeuger nicht optimal. Es bietet sich an, das Gas bei der Verbrennung einen guten Teil seiner Exergie in Reinform zur Verfügung stellen zu können, in dem es z.B. in einem Gasmotor mechanische Arbeit leisten darf, die über einen Generator zu elektrischem Strom veredelt wird, und die Wärmebedarfe in der Brauerei aus dem Abgas und dem Kühlwasser des Motors gedeckt werden. Diese Form des gasbetriebenen Blockheizkraftwerkes (BHKW) ist in der Industrie seit einiger Zeit weit verbreitet. Der Strom deckt Bedarfe durch Elektromotorenantriebe, Kälteerzeugung mit Kompressions-Kältemaschinen, Lüftungsventilatoren, Pumpen und Beleuchtung. Überschüssiger Strom kann ggf. an den Stromversorger verkauft werden.
Der Wärmebedarf für den Brauprozess, sowie für die Wärme im Flaschen- und Fassreinigungsprozess, sowie zur Pasteurisierung des Bier (bei Rückgewinnung eines Teils der Wärme auf leicht niedrigerem Temperaturniveau) wird durch eine Wärmebedarfsauslegung des BHKW weitestgehend gedeckt. In der Ausführung des BHKW sollte berücksichtigt sein, dass die Wärme in ausreichender Menge bei höherer Temperatur durch optimale Nutzung des heißen Abgases entnommen wird, um auf jeden Fall den Dampfbedarf in der Würzepfanne zu decken.
Located in the Urubamba mountain range, the Chicón glacier is the third highest tropical glacier of this area and the source of water for the Chicón watershed. Moreover, from this watershed four communities obtain water for human consumption and agriculture, which is their main economic activity. In the last years glacier retreat is evident in the area and threatens the livelihoods of the people because it affects the availability of fresh water.
The general objective of this research is to analyse the perception of people living in this watershed to climate change, disaster risk, and ecosystem-based solutions. The specific objectives are to identify natural hazards and climate change effects in the community, to recognise potential ecosystem services suitable for Ecosystem-based Adaptation (EbA) and Ecosystem-based Disaster Risk Reduction (Eco-DRR), and to assess to which climate change effects and disasters the communities are vulnerable based on their own perception. The methodological steps are based on literature review, expert interviews, questionnaires to the community, a workshop and field observations.
The results show that people perceive changes in the climate such as increase in temperature, less precipitation and shifts of the rainy and the dry season. The climate-related disasters that were identified are Glacier Lake Outburst Flood (GLOF), droughts, frosts and hailstorms. However, GLOFs are not frequent in the area and drought is the hazard that people consider will be more frequent. Additionally, pests were identified as biological hazards. Several ecosystems services can be obtained for EbA and Eco-DRR from forests, especially if native trees such as Qiwiña (Polylepis spp.), Chachacoma (Escallonia resinosa) and Aliso (Alnus jorullensis) are used in ecosystem management. Finally, the hypothesis was partially accepted since people in the study area are to some extent aware of climate change impacts, but only partially understand causes and effects. Further, they recognize most of the ecosystem services that forests provide. Therefore they are starting to implement ecosystem-based solutions in the watershed with the support of external institutions.
Anaerobic Digestion of spent grains: Potential use in small-scale Biogas Digesters in Jos, Nigeria
(2014)
In order to ascertain biogas yield potential and applicability of spent grains (SG)1 in small-scale biogas production, laboratory batch fermentation was performed with various masses of dry and wet SG using sewage sludge (SS)2 and digested maize silage (DMs) 3 as inoculums. Different volumes of biogas and CH4 were measured with higher volumes observed for batch fermentation with DMs in com-parison to those produced by SS. Results from the study reveals minimum biogas yield of 118.10 L/kg
VS and maximum yields of 769.46 L/kg VS, which are indicative of the possible use of SG for domestic biogas production in Jos, Nigeria. The study established the fact that the use of both dry and wet SG results in the yield of a useful amount of biogas having 40 - 60 % CH4 content depending on the inoculum and amount of volatile solids present. Using the parameters of dry matter and volatile solids contents analysed for SG and DMs, it was estimated that a reactor volume of 6.47 m3 would be capable of meeting the daily cooking needs of rural households in Jos, Nigeria.