Lehre

Effect of planting density and spatial arrangement on biological nitrogen fixation in maize and soybean intercropping systems.

• Background: The proposed study is part of our EU-funded project called LEG4DEV. Overall, the LEG4DEV project focused on legume-based agroecological intensification of maize and cassava cropping systems in Sub-Saharan Africa for water-food-energy nexus sustainability, nutritional security & livelihood resilience. The project works within and across eastern (Ethiopia) and southern Africa (Zambia, Malawi, Tanzania) to test and adapt new innovations for diversifying maize or cassava cropping system through legume integration that will generate transformative impacts on smallholder livelihoods while strengthening the sustainability and climate resilience. In our working group, we will explore how various spatial arrangements, planting density and nutrient  applications rates affect biological nitrogen fixation (BNF) among the component crops. To achieve the above objectives, research trials have been designed in collaboration with partners from SLU in  Sweeen, and Excellence in Agronomy (EIA)-CIMMYT/IITA  across the project countries.
• Research site:  The study will be conducted in Chitedze Research Station, Malawi, where a number of maize and soybean intercropping systems trials have been initiated by our partners in 2023.
• Research topic:The overall aim of the masters thesis is to explore how various spatial arrangements, planting density and nutrient  applications rates affect the biological nitrogen fixation (BNF)  in maize and soybean intercropping systems.The MSc study will include field data collection (above and below ground parameters), and stable isotope analysis across various combinations.
• Type of work: Field Work, Lab Work
• Place of thesis work: University of Hohenheim & Stay abroad
• Starting time: any time
• Travel support: available
• Thesis language: English
• What we expect: A solid knowledge basis of plant and soil science is needed. Experience in field experimentation and laboratory analysis is of advantage but training and support will be provided.
• Contact: Adam M. Adam (am.adam@uni-hohenheim.de), Prof. Georg Cadisch (georg.cadisch@uni-hohenheim.de)

Assessing integrated crop-shrub-tree systems defined by stakeholders in SSA using a landscape modelling approach.

• Background: The proposed study is part of our EU-funded project SustainSAHEL operating in Westafrica. The objective of SustainSAHEL is to enhance the resilience and intensification potential of smallholder agricultural farming systems to climate change through scalable innovations on crop-shrub-livestock (CSL) integration. SustainSAHEL will assess adoption and scaling potential of improved CSL integration, while simultaneously optimizing proven technologies, improving herder-farmer cooperation, tackling socio-economic constraints for adoption and contributing to local economic revival. The approach is embedded within the production systems of agro-ecology and organic agriculture, while comprising elements of conservation agriculture. Investigations on CSL, as well as soil quality and hydrology will be conducted through on-station and on-farm experiments and demonstration plots. We will identify drought resistant shrub teams that are in synchrony with livestock requirements, and reduced tillage options that enhances the soil water capture and holding capacity. At the regional level, landscape modelling scenarios will analyse the promoted systems’ resilience to climate change in West Africa.
• Research site: SustainSahel operates at 7 sites in Senegal, Mali and Burkina Faso. Study  site will be Niakhar, where a number of long-term experiments have been initiated by our partners in 2018. This site is characterised by parkland systems of Faidherbia albida in combination with millet or groundnut. Other crops grown in the area include water melon.
• Research topic: We will assess the production potential and resilience as well as potential environmental impacts of the system under different scenarios that reflect natural gradients (e.g. a gradient in tree density) or interests of local stakeholders, e.g., new crops, changing management of animal browsing, changed tree pruning regime. We will also look into climate change scenarios. The MSc study will include parameterisation and validation of the LUCIA (lucia.uni-hohenheim.de) model using existing field data and translation of stakeholder discussions resulting from Innovation Platforms organized by colleagues in SustaionSahel into model scenarions.
• Type of work: Desktop Work
• Place of thesis work: University of Hohenheim 
• Starting time: any time
• Thesis language: English
• What we expect: A solid knowledge basis of plant and soil science is needed. Experience in model applications is of advantage but training and support will be provided.
• Contact: Dr. Carsten Marohn (carsten.marohn@uni-hohenheim.de), Prof. Georg Cadisch (georg.cadisch@uni-hohenheim.de)

Nutrient balance and N2 fixation in Faidherbia based cropping systems in Senegal.

• Background: The proposed study is part of our EU-funded project SustainSAHEL operating in Westafrica (https://www.sustainsahel.net/about.html). The objective of SustainSAHEL is to enhance the resilience and intensification potential of smallholder agricultural farming systems to climate change through scalable innovations on crop-shrub-livestock (CSL) integration. SustainSAHEL will assess adoption and scaling potential of improved CSL integration, while simultaneously optimizing proven technologies, improving herder-farmer cooperation, tackling socio-economic constraints for adoption and contributing to local economic revival. The approach is embedded within the production systems of agro-ecology and organic agriculture, while comprising elements of conservation agriculture. Investigations on crop performance in CSL, as well as on soil quality and hydrology are being conducted through on-station and on-farm experiments and demonstration plots. The project aims of the project is to identify drought resistant shrub-crop combinations and better understand interaction in such mixed systems in these semiarid regions. SustainSahel operates at 7 sites in Senegal, Mali and Burkina Faso.
• Research site: The proposed MSc study site will be Niakhar in Senegal, where a number of longterm experiments have been initiated by our partners (IRD/CIRAD) in 2018. This site is characterised by parkland systems of Faidherbia albida in combination with millet or groundnut. The case of cropping under Faidherbia trees is particularly interesting since the tree has an inverse phenology (i.e. shedding its leave in the rainy season).
• Research topic: The MSc study will assess nutrient balances and N2 fixation in Faidherbia albida based cropping systems. A database of samples and data collected from 2018-2022 is already available for assessing the nutrient balances of N, P, and K in millet and groundnut grown under, at the edge or outside of trees. The student will additionally analyse N2 fixation of groundnut (and potentially Faidherbia) to be able to compile nutrient balances and assess the sustainability of these systems.
• Type of work: Field Work, Lab Work
• Place of thesis work: University of Hohenheim & Stay abroad
• Starting time: any time but preferentially before cropping season June/July
• Travel support: No, candidate has to apply for fellowship
• Thesis language: English
• What we expect A solid knowledge of plant and soil science is needed. Training in isotope analysis for N2 fixation will be provided. Some basic knowledge of French is of advantage.
• Contact: Dr. Eric Koomson (eric.koomson@unihohenheim.de) , Prof. Georg Cadisch (georg.cadisch@uni-hohenheim.de)

Impact of legumes on manure quality and soil fertility.

• Background: Legumes are an important pillar in developing more sustainable management options. Legumes through the ability to fix atmospheric N contain high protein content in both vegetative and grains. Through recycling of organic materials legumes can improve soil fertility. Legumes are, however, also important components of animal feeds and can enhance animal productivity. Depending on N use efficiency of the animal a considerable amount of N is excreted via urine and manure. These materials can be recycled either in the pasture directly or used to improve soil fertility of cropped fields. Enhancing nutrient cycling in integrated crop-livestock systems is an important strategy to develop more sustainable farming system in the tropics where inputs of mineral fertilizers are not always feasible.
• Research area: Literature search on effect of different animal feeding strategies, with particular emphasis on inclusion of legumes, on manure quality, soil fertility and crop productivity.

Upon interest the work can also be extended to modelling the interaction of animal feed quality, soil fertility and productivity using an integrated modelling approach. 

• Type of work: Desktop Work
• Place of thesis work: University of Hohenheim
• Starting time: any time
• Thesis language: English
• What we expect: A solid knowledge basis of plant and soil science is welcome.
• Contact:  Prof. Georg Cadisch (georg.cadisch@uni-hohenheim.de)

Impact of legumes on manure quality and soil fertility.

• Background: Legumes are an important pillar in developing more sustainable management options. Legumes through the ability to fix atmospheric N contain high protein content in both vegetative and grains. Through recycling of organic materials legumes can improve soil fertility. Legumes are, however, also important components of animal feeds and can enhance animal productivity. Depending on N use efficiency of the animal a considerable amount of N is excreted via urine and manure. These materials can be recycled either in the pasture directly or used to improve soil fertility of cropped fields. Enhancing nutrient cycling in integrated crop-livestock systems is an important strategy to develop more sustainable farming system in the tropics where inputs of mineral fertilizers are not always feasible.
• Research area: Literature search on effect of different animal feeding strategies, with particular emphasis on inclusion of legumes, on manure quality, soil fertility and crop productivity.

Upon interest the work can also be extended to modelling the interaction of animal feed quality, soil fertility and productivity using an integrated modelling approach. 

• Type of work: Desktop Work
• Place of thesis work: University of Hohenheim
• Starting time: any time
• Thesis language: English
• What we expect: A solid knowledge basis of plant and soil science is welcome.
• Contact:  Prof. Georg Cadisch (georg.cadisch@uni-hohenheim.de)

4905-211 - Ökozonen und Kulturpflanzen der Tropen - Vorlesung

Die Studierenden erlangen grundlegende Kenntnisse über die globale Verteilung und Charakteristika von Ökozonen, mit Fokus auf die Tropen und deren Vielfalt an Agrarsystemen und Kulturpflanzen. Wechselbeziehungen und Regulationsmechanismen biotischer und abiotischer Faktoren in Agrarökosystemen und deren Umwelt (Agrarlandschaften, Biodiversität) werden hier berücksichtigt.

Die Studierenden erlangen grundlegende Kenntnisse, warum Agrarökosysteme in den Tropen an die Regenerationsfähigkeit und Belastbarkeit der Umwelt angepasst werden muss, um hinsichtlich des globalen Wandels (z.B. Klimawandel, Bevölkerungsdruck, Ernährungssicherheit) nachhaltig sichere Ertragsleistungen erwirtschaften zu können.

Die Studierenden werden in die Lage versetzt, die mit der landwirtschaftlichen Produktion verbundenen Umweltprobleme in den Tropen zu beurteilen und ökologisch orientierte Lösungskonzepte zu bewerten.

4905-411 - Weltwirtschaftspflanzen und Weidewirtschaft in den Tropen und Subtropen - Vorlesung mit Seminar

Weltwirtschaftspflanzen
Die Studierenden erhalten einen Überblick über weltwirtschaflich bedeutende Kulturpflanzen. Neben genussmittel-, stärke- und öllierfernden Pflanzen werden tropische Wurzel- und Knollenfrüchten sowie technisch nutzbare Pflanzen vorgestellt. Darüber hinaus werden einige Vertreter aus der ernährungsphysiologisch wichtigen Familie der Körnerleguminosen behandelt. Die Studierenden erwerben Kenntnisse über die wirtschaftliche Bedeutung, Herkunft, Botanik, Verbreitung, ökophysiologische Ansprüche, Anbau, Ernte und Verarbeitung der behandelten Kulturpflanzen und können diese in der Praxis anwenden.

Weidewirtschaft

• Einführung: Bedeutung der tropischen Weidewirtschaft; Tropen als weidewirtschaftlicher Produktionsraum; weidewirtschaftliche Produktionssysteme mit Problemanalyse
• Weide- und Futterpflanzen: Allgemeines; Gräser, Leguminosen, Futterbüsche & -bäume
• Genressourcen und Züchtung
• Versuchsmethodik
• Bodenverbesserung durch Futterpflanzen
• Krankheiten und Schädlinge
• Saatgutproduktion
• Weideanlage
• Düngung
• Weidenutzung und -management
• Futterkonservierung

4905-421 - Crop Production Systems - Vorlesung mit Übung und Seminar

• Introduction: potentials and constraints of intensification in world food production, principles of plant production in the tropics.
• Crops and Nutrition: importance of cereals and root crops for human nutrition, importance of minor crops and plant genetic resources for a sustainable development.
• Cropping Systems: Crop rotation and mixed cropping; Interactions in multiple plant component systems.
• Methods of quantifying plant growth.
• Plant Growth and Resource Use: Eco-physiology of rice and cassava.
• Plant Improvement: Plant adaptation mechanisms to stress.
• Soil Fertility and Conservation Systems: Principles of soil fertility and degradation;
  • Legumes - source of food security and sustainability;
  • Nutrient management and environmental services;
  • Resource protection on sloping land.

• Alternative Plant Production Systems: Fibers; Biofuel and industrial applications.
• Crop Modelling: Concepts; Application in crop production.
• Tools for evaluating integrated Systems: Integrated modelling approaches - LUCIA;
  • Case studies;
  • Group computer modelling exercises.

• Interdisciplinary case studies: Students seminar.

3000-821 - Methods of Scientific Working - Vorlesung mit Seminar

Overall Objectives:
- Scientific and interdisciplinary competence
- Awareness of the wider scientific related environment
- Acquisition of basic tools for a PhD study and scientific career
- Excellent qualification and preparation for future challenges

Specific topics:
- Scientific Environment (relationship with society, organisation and cooperation in research projects, ethic issues, intelectual property rights)
- Toolbox for thesis writing (literature search and databases, special cases in statistics, writing up and presentation)
- How to publish? (where to publish, citation index, writing guidlines)
- Funding in Science (funding bodies, proposal writting)
- International organisations
- Survival strategies (coping with stress)

4905-431 - Integrated Agricultural Production Systems - Vorlesung mit Seminar

INTRODUCTION: Socioeconomic aspects of integrated agricultural production systems; Biological and technical aspects of integrated agricultural production systems; The role of legumes. AGROSILVOCULTURAL SYSTEMS: Rationale, history, regional importance, and examples; Shrub and tree species for agrosilvocultural systems; Tree/crop interactions; Improved Fallows, Alley cropping; Homegardens; Modelling approaches in agroforestry (examples/practical (if possible)). AGROPASTORAL SYSTEMS: Rationale, history, regional importance and examples; Ley-farming (case study); Animal/crop interactions; Crop residues quality and utilization; Forage plant/crop interactions; Forage species for agropastoral systems: grasses and legumes. SILVOPASTORAL SYSTEMS: Rationale, history, regional importance, and examples; Animal/tree interactions; Forage quality of tree foliage; Forage plant/tree interactions; Forage species for silvopastoral systems. BEE PRODUCTION IN THE TROPICS: Principles and local excursion (if possible) RESOURCE USE: Integrated Plant Nutrient Management (IPNM); Integrated Soil Fertility Management (ISFM); Methods to assess interactions and impact in integrated production systems. PLANT PROTECTION IN IAPS. General principles, system interactions with pests and diseases. Examples: Push-Pull, biological control of Striga (parasitic weed). SOCIO-ECONOMIC CONSIDERATIONS: Sociological methods related to development and adoption of integrated production systems production technology. Cost-benefit analysis and sustainable use of natural resources. Lectures, discussions. Student seminars; Powerpoint & PDF presentations, videos. Practical part: Hands on the Water, Nutrient, and Light Capture in Agroforestry Systems (WaNuLCAS) model (if possible)

Info text

4905-461 - Modeling of Agroecosystems - Vorlesung mit Übung und Praktikum

Modeling
Introduction to principles of crop models and development of own model modules by the students. We will jointly develop a base model on photosynthesis and assimilate partitioning in annual crops using Stella, a user-friendly visual software. During individual or group-wise work students will build own modules that can be plugged into the base model. The course will be held in an interactive manner and we will use our models to discuss topics like feedback loops, competition, model calibration / validation and others as they arise during the practical work. Students will present their models at the end of the course, including quantitative assessment (plausibility) of outputs.

Ecophysiology and Analysis of Growth and Development
This lecture provides knowledge on growth and development of four tropical crops (rice, cassava, oil palm and cowpea) and the concept of crop growth analysis. The impact of temperature, day length, photoperiodism and solar radiation will be discussed.
In the practical part, students apply field methods to determine crop growth rates, leaf area index and light transmission.
V (50%), P (50%)

4905-471 - Biodiversity and Genetic Resources - Vorlesung mit Seminar und Exkursion

This module gives an overview of fundamental aspects of biodiversity in natural and agricultural ecosystems. These include patterns of global species diversity and the determinants of biodiversity at different scales, species-area relationships, abiotic and biotic factors affecting biodiversity, methods of diversity analysis. It also includes the various threats to biodiversity. Agricultural diversity is considered regarding crop diversity, diversity of agroecosystems, species interactions, effects of management on biodiversity and pollination, as well as plant genetic resources and their maintenance including seed storage. In addition, a focus is given to natural and agricultural diversity of the tropics. Lectures and discussions, seminars and handouts prepared by students, field trips and small excursions are included.