U. Schmidt

U. Schmidt
Humboldt-Universität zu Berlin | HU Berlin · Department of Crop and Animal Sciences

Full Professor

About

195
Publications
50,049
Reads
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1,229
Citations
Citations since 2016
72 Research Items
934 Citations
2016201720182019202020212022050100150
2016201720182019202020212022050100150
2016201720182019202020212022050100150
2016201720182019202020212022050100150
Introduction
U. Schmidt currently works at the Albrecht Daniel Thaer-Institut for Agricultural and Horticultural Sciences , Humboldt-Universität zu Berlin. U. does research in Horticultural and Biosystems Engineering. Their current project is "CUBES Circle" Closed urban modular energy- and resource efficient agricultural systems
Additional affiliations
April 2014 - present
Humboldt-Universität zu Berlin
Position
  • Director of institute
January 1993 - present
Humboldt-Universität zu Berlin
Position
  • Professor (Full)
Description
  • biosystems engineering, greenhouse technology, intelligent sensor technologies, agricultural engineering

Publications

Publications (195)
Article
Full-text available
Shortage of water availability and awareness of the need for sustainable resource management have generated a significant increase in the use of recycled water for irrigation and processing of crops and harvest products, respectively. As a result, irrigation systems face the challenge of neutralizing plant pathogens to reduce the risk of their disp...
Article
Full-text available
Concepts of semi-closed greenhouses can be used to save energy, whereas their technical equipment often causes a decrease in the light received by the plants. Nevertheless, higher yields are achieved, which are presumably triggered by a higher CO2 concentration in the greenhouse and associated higher photosynthesis because of the technical cooling...
Article
Full-text available
High-pressure sodium (HPS) lighting is increasingly replaced by LED lighting in lettuce greenhouse cultivation. In contrast to HPS lighting, LEDs do not heat radiation. Therefore, the leaf temperature is significantly lower under LEDs. This raises the question of whether LED lighting has a positive impact on the reduction in water consumption durin...
Article
Full-text available
Light emitting diodes (LEDs) are an energy efficient alternative to high-pressure sodium (HPS) lighting in tomato cultivation. In the past years, we have learned a lot about the effect of red and blue LEDs on plant growth and yield of tomatoes. From previous studies, we know that plants absorb and utilize most of the visible spectrum for photosynth...
Article
Full-text available
This work presents an adaptive architecture that performs online learning and faces catastrophic forgetting issues by means of an episodic memory system and of prediction-error driven memory consolidation. In line with evidence from brain sciences, memories are retained depending on their congruence with the prior knowledge stored in the system. In...
Article
Full-text available
Combining information of plant physiological processes with climate control systems can improve control accuracy in controlled environments as greenhouses and plant factories. Through that, resource optimization can be achieved. To predict the plant physiological processes and implement them in control actions of interest, a reliable monitoring sys...
Article
Full-text available
Combining information of plant physiological processes with climate control systems can improve control accuracy in controlled environments as greenhouses and plant factories. Through that, resource optimization can be achieved. To predict the plant physiological processes and implement them in control actions of interest, a reliable monitoring sys...
Preprint
Full-text available
This work presents an adaptive architecture that performs online learning and faces catastrophic forgetting issues by means of episodic memories and prediction-error driven memory consolidation. In line with evidences from the cognitive science and neuroscience, memories are retained depending on their congruency with the prior knowledge stored in...
Conference Paper
Full-text available
Due to light conditions, cultivation of lettuce on the south side of the buildings is preferable. With regard to heavy metals, our study did not reveal any health risk due to consumption of lettuce produced under urban conditions with different air pollution levels. Nevertheless, the accumulation of heavy metals increased in unwashed and washed sam...
Article
Wiederverwendbares Wasser kommt ohne Desinfektionsmittel nicht aus - vor allem bei der geschlossenen Bewässerung. Chemische Verfahren sind sehr wirkungsvoll, bergen aber die Gefahr von Pflanzenschäden und Desinfektionsrückständen. Ein neues Verfahren soll genau diese Gefahren minimieren. // Zeitschrift Gemüse - Das Magazin für den professionellen...
Article
Consumer and trade organisations demand year-round healthy diets including fresh, high quality vegetables from local producers. However, greenhouse gas emissions (GHG) of heating high-tech greenhouses in northern countries are higher than transporting vegetables produced in southern Europe in unheated tunnels. The aim of this work was to assess GHG...
Article
Full-text available
// Broschüre zur Innovationsförderung des Bundesministeriums für Ernährung und Landwirtschaft: Förderverfahren, Themenfeldern und Beispiele aus der Praxis der Innovationsförderung - Themenschwerpunkt Pflanze. Hrsg. Bundesanstalt für Landwirtschaft und Ernährung (BLE), pp. 23-24 //
Article
Artificial neural networks (ANN) have been successfully used for modelling climate and plant signals in greenhouses. This work shows the combination of two ANN models, built and trained separately, and then coupled together. Both models were trained using a data set consisting of 3 complete cultivation periods (2011 until 2013) of 2 venlo-type gree...
Article
Tested in experimental scale, an innovative system for electrolytic water disinfection in greenhouses (SeWiG) was very efficient. It was developed by Humboldt-Universität zu Berlin and newtec Umwelttechnik GmbH. With scaling up this system for industrial greenhouses, the new technology will be tested, validated and optimized under practical conditi...
Article
Closed fertilisation systems improve the water use efficiency of greenhouse crop production, which reduces groundwater pollution considerably. However, the uptake ratio of water and the individual nutrients is not constant over the cultivation period of most crops. This may result in ion imbalances in the nutrient solution if the composition of the...
Article
Aquaponics combine the production of fish and plants in a sustainable way due to the double use of water and nutrients. Compared to conventional single recirculation aquaponic systems (SRAPS), the double recirculation aquaponic systems (DRAPS) are improved by the combination of two separate recirculating systems: the recirculating aquaculture syste...
Article
The research was focused on the identification of interactions between hypochlorite used as a disinfectant for a recirculating tomato production system and the spread of microorganisms, plant characteristics and fruit quality. Potassium hypochlorite (1% KCLO) supplemented once a week for 90 min into different nutrient solution ranks until a free ch...
Article
Artificial neural networks (ANN) have been successfully used for modelling climate and plant signals in greenhouses. This work shows the combination of two ANN models, built and trained separately, and then coupled together. Both models were trained using a data set consisting of 3 complete cultivation periods (2011 until 2013) of 2 venlo-type gree...
Technical Report
Full-text available
Im Produktionsgartenbau besteht bei geschlossener Bewässerung ein erhöhtes Verbreitungsrisiko von wasserübertragbaren Pflanzenkrankheitserregern. Hierzu weisen die gängigen Verfahren zur Wasserdesinfektion zwar eine hohe Effizienz bei der Eliminierung von Pilzen und Bakterien auf, können aber Viren nur mit hohem Energieaufwand (Wärmebehandlung > 90...
Poster
Full-text available
Varying conditions of cultivation of vegetables inside a city’s boundaries were analyzed. As such, in the city of Berlin flower boxes with lettuce were installed at 20 spots at different heights, with different light conditions and air pollution levels. In order to exclude heavy metal uptake due to soil contamination, lettuce was seeded in a standa...
Conference Paper
Full-text available
Zu den großen Herausforderungen des 21. Jahrhunderts gehört die Folgeneindämmung des durch Treibhausgasemissionen (THG-Emissionen) verursachten Klimawandels. Hierbei ist der Agrarsektor ein beachtlicher Emittent, darunter die wachsende Gewächshausbranche mit CO2-Emissionen. Daher erforscht und entwickelt das MinTHG-Konsortium, bestehend aus mehrere...
Poster
Full-text available
Zu den großen Herausforderungen des 21. Jahrhunderts gehört die Folgeneindämmung des durch Treibhausgasemissionen (THG-Emissionen) verursachten Klimawandels. Hierbei ist der Agrarsektor ein beachtlicher Emittent, darunter die wachsende Gewächshausbranche mit CO2-Emissionen. Daher erforscht und entwickelt das MinTHG-Konsortium, bestehend aus mehrere...
Technical Report
Full-text available
In der Machbarkeitsstudie ELGEVOS wurde der Gewächshausbetrieb durch eine computersimulierte Lastverschiebung entsprechend den Preisschwankungen am Strommarkt optimiert, um geringere Stromkosten zu erreichen. Dabei wird die im konventionellen Betrieb auf Zeiten mit hohen Strompreis fallende Last reduziert bzw. auf einen späteren Zeitpunkt mit niedr...
Article
Full-text available
The integration of agricultural production systems into urban areas is a challenge for the coming decades. Because of increasing greenhouse gas emission and rising resource consumption as well as costs in animal husbandry, the dietary habits of people in the 21st century have to focus on herbal foods. Intensive plant cultivation systems in large ci...
Article
In contrast to conventional single recirculation aquaponic systems (SRAPS), the innovative double recirculating aquaponic system (DRAPS) provides an opportunity for intensive fish and plant production. This system is based on two separate recirculating systems, a recirculating aquaculture system (RAS) and a closed hydroponic system, whereby the com...
Article
Mexico City and its metropolitan area is one of the main megacities in the world; by 2016 had a population of 21.2 million people and covered an area of 4,979 km2. This tremendous rate of substitution of natural landscape into urban elements from 1960 till 2016 have gradually altered the local rainfall and temperature patterns of the basin. The inc...
Conference Paper
Full-text available
In zirkulierenden Bewässerungssystemen kann es zu einer Anreicherung und Verbreitung von Phytopathogenen kommen. Dies macht phytosanitäre Maßnahmen notwendig. Im Rahmen dessen wurde das System zur elektrolytischen Wasserdesinfektion in Gewächshäusern [SeWiG] entwickelt. Da beim Einsatz dieser Methode unter anderem Chloratanionen als Nebenprodukt en...
Article
The increase of global population causes rising food demand and concomittantly scarcity of resources. These facts including global warming need the further development of resource-efficient food production systems such as double recirculating aquaponic systems (DRAPS). This recent technology is suitable for intensive food production with minimal re...
Poster
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Over time the human population has become increasingly urban. The proportion of city dwellers increased from 30% in 1950 to 66% in 2015. Due to this concentration of people in densely-built areas, a rethinking of agricultural and horticultural production is needed urgently. While the demand for fresh vegetables and other natural resources such as w...
Poster
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Der deutsche Gartenbau befindet sich im Spagat zwischen einem hohen internationalen Wettbewerb einerseits und einem starken Preisdruck von Seiten der Abnehmer andererseits. Hinzukommt, dass der Lebensmitteleinzelhandel verstärkt Informationen zum Ressourceneinsatz einfordert. Infolgedessen gewinnt in gartenbaulichen Produktionsbetrieben die ressour...
Conference Paper
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Die anstehenden Veränderungen im Energiesektor im Zuge der Abkehr von fossiler Energie hin zu den erneuerbaren Energien sind groß. Um auch zukünftig die Versorgungssicherheit zu gewährleisten, bilden Energiespeicher und energieeffiziente Maßnahmen zentrale Elemente dieser Veränderungen. Dies gilt sektorenübergreifend und für alle Wirtschaftszweige,...
Conference Paper
Full-text available
Die HU Berlin hat mit der Fa. newtec das System zur elektrolytischen Wasserdesinfektion in Gewächshäusern (SeWiG) entwickelt. Dabei wird vor Ort mittels Elektrolyse aus einer Sole (KCl) eine Desinfektionslösung (KClO) produziert. Diese wird in einem Speichertank bevorratet und bei Bedarf über eine sensorbasierte Dosierung dem Gießwasser bzw. der Nä...
Conference Paper
Full-text available
Von der HU Berlin und Fa. newtec wurde das System zur elektrolytischen Wasserdesinfektion in Gewächshäusern (SeWiG) entwickelt. Das bereits im kleinen Versuchsmaßstab erfolgreich getestete Desinfektionssystem wird nun unter Praxisbedingungen auf große Gewächshäuser mit entsprechenden Wasservolumina hoch skaliert und optimiert. In der gärtnerischen...
Poster
Full-text available
Von HU und Fa. newtec wurde das System zur elektrolytischen Wasserdesinfektion in Gewächshäusern (SeWiG) entwickelt. Das bereits im kleinen Versuchsmaßstab getestete Desinfektionssystem wird nun unter Praxisbedingungen auf große Gewächshäuser mit entsprechenden Wasservolumina hoch skaliert und optimiert. In der gärtnerischen Praxis besteht vor alle...
Poster
Full-text available
Um die Übertragung wasserbürtiger Phytopathogene zu unterbinden, kommt der Desinfektion von Gießwasser bzw. Nährlösung eine zentrale Bedeutung zu. Das von der Firma newtec und der HU Berlin entwickelte System zur elektrolytischen Wasserdesinfektion in Gewächshäusern (SeWiG) ist wirksam gegenüber einem breiten Spektrum an pflanzlichen Krankheitserre...
Poster
Full-text available
Ionenselektive Elektroden (ISE) werden meist in Laboren zur potentiometrischen Bestimmung der Aktivität eines bestimmten Ions in einer Lösung mit verschiedenen Ionen verwendet. Für die Pflanzenernährung relevante Elektroden sind unter anderem für NO3-, K+, Ca2+, Na+ und Cl—Ionen verfügbar. Der Einsatz von ISE in der gartenbaulichen Praxis scheitert...
Conference Paper
Full-text available
An increasing amount of greenhouse vegetables is produced using hydroponic systems. The used mineral fertilizers are often generated in energy consuming processes (esp. nitrate in Haber-Bosch) or gained from finite resources (esp. phosphate rock). Recovering the respective nutrients from waste streams is a promising option to make crop production m...
Article
The trend in greenhouse automation systems is to listen to plant signals while trying to minimize the ecological footprint of the vegetable production. In this work,we present a model based on artificial neural networks (ANN), which can be used to support the measuring of plant signals and help to improve the reliability of the data collected. This...
Poster
Full-text available
Due to the fact that greenhouses need big amounts of energy (esp. for heating purposes in temperate zones), there is a growing interest on new technical systems to save energy and fossil resources. In this context, the inclusion of active solar thermal systems in greenhouses for energy harvesting and plant production represents an interesting solut...
Poster
Full-text available
The use of ion-selective electrodes in closed irrigation systems is possible, but the environmental conditions must be adapted. Feeding the samples to the ISE-measuring system enables automated calibration and control of ISE. Also the lifetime of ISE is increased if these are not permanently in liquids. Changes in the ion concentrations of nutrient...
Article
Full-text available
Growing environmental and sustainability concerns have driven continual modernization of horticultural practices, especially for urban farming. Controlled environment and soilless production methods are increasing in popularity because of their efficient resource use and intensive cropping capabilities. However, some popular substrates used for hyd...
Conference Paper
Full-text available
In the present experiment, the fruit growth is to be recorded using a modified smart phone camera. Firstly, the project aims at correct sizing of round fruits like e.g. tomatoes, as precisely as possible. Reference areas are used to determine the size. The masks with defined dimensions can be attached to the observation objects and enable an exact...
Poster
Full-text available
Zusammenfassung: Im vorliegenden Versuchsansatz soll das Fruchtwachstums mithilfe einer modifizierten Smartphone-Kamera erfasst werden. Als Projektziel steht zunächst eine möglichst exakte Größenbestimmung runder Früchte wie z.B. Tomaten. Zur Größenbestimmung werden Referenzflächen genutzt. Die Masken mit definierten Abmessungen können an die Beoba...
Conference Paper
Full-text available
Gegenwärtig liegt der Anteil der erneuerbaren Energieträger (z.B. Wind- und Sonnenenergie) bei der jährlichen Stromerzeugung in Deutschland bei etwa 35%. Bis zum Jahr 2030 will die Bundesregierung diesen Anteil auf 50% erhöhen. Andere EU-Staaten haben ähnlich Pläne. Prognosen zeigen, dass dies die Volatilität (Schwankung) der Stromerzeugung und -pr...
Article
A dynamic artificial neural network was developed to predict tomato yield in two high-technology greenhouses located at Humboldt University of Berlin. One is a reference greenhouse, the other is a semi-closed greenhouse, called a solar collector. Both greenhouses have a surface area of 307 m2, and they are equipped with a phytomonitoring system for...
Presentation
Full-text available
Net photosynthetic rate per unit leaf area(PN) is regarded as a standard parameter indicating the maximum photosynthetic activity of leaves under the measurement environmental conditions, which can be measured non-destructive and in real time by gas exchange instruments, e.g., using BERMONIS. However, it is not quite clear if it is possible to calc...
Conference Paper
Full-text available
Mit geschlossenen Düngungs-und Bewässerungssystemen können die Wassernutzungseffizienz von Gewächshauskulturen verbessert und Nährstoffausträge in die Umwelt verhindert werden. Allerdings ändert sich das Nährstoffaufnahmeverhalten im Kulturverlauf, zum Beispiel durch veränderte Klimabedingungen und zu unterschiedlichen Entwicklungsstadien. Dies kan...
Conference Paper
Full-text available
In Germany, the growing introduction of electricity generated from renewable energy creates variability on electricity tariffs. The present research is based on the idea of taking advantage of low electricity prices for supplemental illumination in greenhouse production. Due to the variation of electricity prices, also the application of the lighti...
Article
Aquaponics for intensive crop production is a highly complex system in which three different biological systems (fish, plants, and nitrifying bacteria) with different requirements must be merged. Finding the right combination is a serious challenge and the dependencies avoid a high productivity until now. Therefore, a unique and innovative double r...
Conference Paper
Full-text available
Im ELGEVOS-Verbund (bestehend aus IGZ, HU und Fraunhofer IWES) sollen Konzepte für Gewächshäuser entwickelt werden, die sich auf eine zunehmende Nutzung von erneuerbaren Energien einstellen (Ziel der Bundesregierung: 50 % bis 2030) und der damit einhergehenden Volatilität des Stromangebots bzw. der Strompreise begegnen. Die Lösungsansätze sollen de...
Article
Effects of organic waste from hydroponic system added with minerals (organo-mineral fertilizer) and synthetic fertilizer on major polyphenols of red oak leaf lettuce using HPLC-DAD-ESI-MS3 were investigated. Interestingly, contents of the main flavonoid glycosides and caffeic acid derivatives of lettuce treated with organo-mineral fertilizer were e...
Poster
Full-text available
Currently, about 33% of Germany’s annual electricity is generated from renewable sources like wind and sun. Until 2030, the German government wants to increase this proportion to 50%. Other EU countries have similar plans. Predictive models indicate that this aim will lead to an increase in volatility of the energy supply and will also affect elect...
Article
Full-text available
The increasing use of recirculating nutrient solutions and drainage water for irrigation purposes requires effective sanitation methods to minimise the dispersal of plant pathogens. Among these, plant viruses are of particular interest because they cannot be cured. A new disinfection system was tested in regard to its ability to inactivate plant vi...
Article
Full-text available
Production of indigenous African leafy vegetables such as African nightshade (Solanum scabrum Mill.), whose high nutritional and medicinal value is well documented is still limited due to insufficient preharvest techniques. Electric current is known to improve quality in food crops. Therefore, in the present study, the effects of direct-electric-cu...
Technical Report
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Bei der Nutzung von Oberflächenwasser zur Bewässerung und einer Wiederverwendung des überschüssigen Wassers ist das Verbreitungsrisiko von Pflanzenkrankheitserregern erhöht. Dies bedingt eine effektive Wasserdesinfektion. Hierzu wurde zunächst in vitro die Wirksamkeit einer durch Salzelektrolyse erzeugten Desinfektionslösung zur Inaktivierung von p...