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    Item type:Publication, Access status: with files ,
    Combining rainwater harvesting and agroforestry system for enhancing crop yield and soil nutrients : a holistic approach towards improved small-holder farming
    (Gesellschaft zur Förderung der Forschung und Entwicklung der Umwelttechnologien an der Technischen Universität Hamburg e.V. (GFEU), 2024-03-29)
    Debebe Bedanie, Yalembrhan
    The study combined rainwater harvesting (RWH), agroforestry (AFS) and soil organic amendment in a holistic approach with the aim to address water scarcity and enhance crop yield in dry areas with limited moisture and depleted soil. The field experiment was conducted in eastern Tigray- Ethiopia following detailed RWH site suitability assessment and evaluation of existing RWH and AFS systems. The results showed BWAFS (RWH, poultry biochar and AFS) significantly increased pH, SOM, TN, Av.P as well as yield and biomass of both crops (maize and barley). The study proved the potential of the holistic approach for improving soil quality and crop yield in arid and semi-arid regions facing water scarcity
    Publicationtype: Book
      85  417
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    Mikroschadstoff-Elimination aus kommunalem Abwasser durch biologischen Schadstoffabbau in Festbettreaktoren unter nitrifizierenden und denitrifizierenden Bedingungen nach verbesserter chemischer Kohlenstoffextraktion
    (2024)
    Stricker, Birthe Kristina
    ;
    Otterpohl, Ralf
    Micropollutants are present in low concentration in water bodies. Due to an inadequate elimination in municipal, mechanical-biological wastewater treatment plants, they represent a main path of entry. In addition to the establishment of micropollutant elimination, e.g. as a fourth treatment step, increasing the energy efficiency of wastewater treatment plants is a current issue in urban water management. The alternative wastewater treatment plant concept MicroStop addresses both issues. In addition to an all-encompassing reduction of particles, nutrients, and multiresistant germs, micropollutants are eliminated by a combination of biological degradation in fixed-bed reactors with physical retention by nanofiltration. The combination process is preceded by enhanced carbon extraction in the pre-treatment stage by coagulation/flocculation. To assess the feasibility of the concept, tests were carried out for enhanced carbon extraction and the biological degradation of micropollutants under nitrification and denitrification in the fixed-bed reactors. Using the coagulation/flocculation chemical Sachtofloc 46.12 at a dosage of 0.2 mmol Al/L wastewater, a further reduction in total organic carbon (TOCN) in the primary clarification effluent of 49 % (wastewater treatment plant A) and 30 % (wastewater treatment plant B) was achieved in 1 Liter jar tests. The reduction was limited by the proportion of dissolved organic carbon (DOCN) in the wastewater, which was 52 % (wastewater treatment plant A) and 68 % (wastewater treatment plant B). A combination of the MicroStop concept with other processes for enhanced carbon extraction, such as POWERSTEP, is possible based on the overall results. In the biological fixed-bed reactors, nitrification with > 99 % reduction and denitrification with 94 – 99 % could be established. In one test phase, nitrite accumulation occurred, which was prevented by adjusting the acetic acid dosage. Three test phases (purely aerobic operation and nitrification/denitrification without/with flocculation supernatant) demonstrated further potential for the biodegradation of some of the pollutants tested. For gabapentin (> 93 to > 98 %), iomeprol (> 69 to > 96 %) and metoprolol (> 62 to > 76 %), very good elimination rates below the limit of quantification were achieved in all test phases under aerobic conditions (with/without nitrification). Diclofenac was reduced with 47 to 67 %, better than known from literature, but never below a threshold concentration of 1.8 – 2.6 µg/L. A longer retention time showed a positive influence. Sulfamethoxazole showed fluctuating results with degrees of elimination between – 42 and 87 %. A reduction only occurred under denitrification and became more stable under increased acetic acid dosing during a longer retention time. Under aerobic conditions, there was an increase in pollutants. A retransformation of the main metabolite N4-acetylsulfamethoxazole is assumed to be the cause. Carbamazepine and its metabolite carbamazepine 10,11-epoxide showed persistent behaviour. The sweetener cyclamate was only detected in one test phase and was very well eliminated with 97 %.
    Publicationtype: Doctoral Thesis
      92  379
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    Item type:Publication, Access status: with files ,
    33. Hamburger Kolloquium zur Abwasserwirtschaft
    (Gesellschaft zur Förderung der Forschung und Entwicklung der Umwelttechnologien an der Technischen Universität Hamburg e.V. (GFEU), 2023-09)
    Tagungsband zum 33. Hamburger Kolloquium zur Abwasserwirtschaft an der TUHH am 05. und 06. September 2023. Themenschwerpunkte der Tagung waren: Abwasserreinigung und Emissionen, Niederschlagswasser und Klimaschutz, Building Information Modeling (BIM), IT Sicherheit und Smart City, Abwasserbehandlung und Emissionen sowie Spurenstoffelimination.
    Publicationtype: Conference Proceedings
      96  544
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    Elimination von Mikroschadstoffen im kommunalen Abwasser durch Nanofiltration in Kombination mit dem biologischen Schadstoffabbau in einem Festbettreaktor
    (2021-08)
    Büning, Bastian
    ;
    Otterpohl, Ralf
    Current wastewater treatment is not designed to eliminate micropollutants (MP) such as pharmaceuticals, pesticides, and microplastics, which is why they enter surface waters via municipal wastewater. A combination of a fixed-bed reactor (FBR) and nanofiltration (NF) was implemented to eliminate MP. The NF acts as a barrier to MP, while biodegradation of the pollutants is induced in the FBR. The experiments show that NF can separate on average more than 93% of MP. Except for two problematic substances, the average biodegradation rate in the FBR was 78%. With a combination plant of NF and FBR, the spectral absorption coefficient SAK270 could be eliminated to 89 %, and this parameter is considered to be of great significance with regard to the amount of MP and their metabolites.
    Publicationtype: Doctoral Thesis
      994  1703
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    Agroecological engineering interventions for food security and sustainable rural development : the case of rice farming in Kashmir
    (Gesellschaft zur Förderung der Forschung und Entwicklung der Umwelttechnologien an der Technischen Universität Hamburg e.V. (GFEU), 2021-02-12)
    Shah, Tavseef Mairaj
    The ecological consequences of industrial agriculture and the pace at which the natural resources of soil and water are being exhausted, make a rethink of food systems imperative. Rice being the staple for more than half the world population and a major water consumer crop can play a vital role in this. This work builds the case for agroecological interventions in rice farming to mitigate the negative impacts of the food system on the environment, to attain sustainable development in rural areas. In this regard, the improvements in plant growth parameters and plant health conditions observed under SRIBI (System of Rice Intensification with Beans Intercropping) are reported. Rice iCrop, based on SRIBI, is presented as an alternative rice farming system due to its wide-ranging socioeconomic and ecological benefits.
    Publicationtype: Book
      1408  1857
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    Treatment and substance recovery in landfill leachate permeates : an alternative sustainable approach
    (2021)
    Melo Pineda, Jairo Dario
    ;
    Otterpohl, Ralf
    In this Doctoral work, landfill leachate is viewed as a RESOURCE without ignoring the environmental problems link to it. Substances including CaCO3-Rich Solids and Concentrated (NH4)2SO4 Solutions (≈20%) were recovered form a landfill leachate permeate generated in a treatment facility located at a landfill site in Northern Germany. Also more than 99% of the inorganic-N was removed from the treated permeates through Nitrification/Denitrification in FBBs. Additionally, explored applications for the reutilization of the recovered substances included pH correction of Acid Soil and Ammonium Sulfate Crystallization.
    Publicationtype: Doctoral Thesis
      589  927
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    Item type:Publication, Access status: with files ,
    Duckweed and Azolla as livestock feed for improving resource efficiency and nutritional quality
    (2020)
    Hügel, Stefan
    ;
    Otterpohl, Ralf
    The floating plants duckweed and Azolla have the potential to produce many times more biomass and protein than conventional crops. They can be used to substitute conventional feed crops in livestock production. Trials with poultry have been conducted, where the offering of both plants was shown to substantially decrease feeding costs and the content of Omega-3 fatty acids in the eggs could be increased.
    Publicationtype: Doctoral Thesis
      768  9726
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    Item type:Publication, Access status: without files ,
      209
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    Towards sustainable development by new town planning : case study of Mazandaran Province of Iran
    (2019)
    Zahedi, Ali
    ;
    Otterpohl, Ralf
    The New Town planning concept was evaluated as an alternative solution for regulating imbalanced urban-rural growth in the Mazandaran province of Iran. The research was conducted in three main aspects. Firstly, local development through creation of small- scale enterprises with low-tech solutions was studied by analysing several small-scale businesses. Secondly, human well-being assessment was conducted in the Kandelous village by considering housing, earning and job, work-life balance, education, environmental quality, health, civic engagement and governance, personal security, social connections, happiness, and life satisfaction topics. Thirdly, the study area was assessed to identify suitable place for creating New Town settlement by using an integrated GIS-AHP technique that was followed by a validation step using high resolution Google Earth images and a field study survey. It was found that small-scale business with low-tech solutions can support a suitable quality of life for local people including a suitable work-life balance. However, this balance highly depends on management skills rather than size of business. In all studied cases, a strong link between business and social development was identified. In all described cases several socio-economic-environmental achievements were detected that are useful for application in other villages. The conducted human well-being assessment in the Kandelous village shows that the surveyed people are happy and satisfied with their life in the village. Moreover, we have detected high well-being status in different topics such as social connections, civic engagement, work- life balance, health, employment rate, and environmental quality. Thus, small-scale settlements can not only play a role in ecological functionality of the region but also can offer an attractive life for people. However, expectations of people about life have a key role in the life satisfaction of people. The LSA assessment indicated that 163.29 Km2 (0.68%) of the study area is highly suitable for creation of New Town settlement. While 2,418.79 Km2 (10.15 %) is moderately suitable, 2,749.06 Km2 (11.53 %) is marginally suitable land, 1,931.86 Km2 (8.10 %) is currently not suitable, 28.38 Km2 (0.12%) is permanently unsuitable. Slope was identified as an important topographical restriction factor in the proposed decision support model, whereas approximately 53.25% of total area was classified as very steep area (30-500 degree). The distribution of existing farms among the suitability classless was determined in 24,000 km2, that was randomly selected. approximately 94 percent of highly suitable, 78 percent of moderately suitable, and 16 percent of marginally suitable lands were used for agricultural activities. At a country level, Miyankaleh, Miyandrodbozorgh, Roodpayshomali, Kalarastaghgharbi, and Golijan counties were determined as the most suitable places for New Town development, whereas about 86.80% of highly suitable lands (141.73 Km2), 14.07% of moderately suitable lands (340.47 Km2), and 3.02% of marginally suitable lands (88.14 Km2) are located in these counties. The field study survey was conducted for the Miankaleh County, the results indicate that this county has a unique environmental quality with a rich fauna and flora. From socio-economic analysis, this county has an imbalanced urban- rural growth, whereas a negative growth rate for rural settlements was detected. Besides, low employment rate (22-37%) can be noted as another socio-economic challenge for this county. Although, several opportunities such as unique environmental quality, close distance to the Caspian Sea, and a good logistic access can be considered for creating New Town settlements.
    Publicationtype: Doctoral Thesis
      543  369
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    Item type:Publication, Access status: without files ,
      183