Nutrient Management in Agro-Ecosystems
(formerly "Soil Fertility Management")

CSS 372, 4 credits

Requirements: CSS 260 or equivalent, basic knowledge of biological and chemical processes are beneficial

Short description

You will become familiar with the basic concepts of soil fertility, and how soil and environmental properties affect nutrient availability and cycling. We will discuss in which way organic farming and soil conservation affect the fate of nutrients in agro-ecosystems. An important issue will be the way nutrient management can be improved without creating environmental hazards. Apart from expanding your knowledge in discussion groups and through oral as well as poster presentations, you will have hands-on training in analytical procedures.

 

This course is designed for all students:

· who are interested in the environmental aspects of nutrient management in agro-ecosystems.
· who want to have a profound knowledge of soil nutrient dynamics and the processes which control nutrient fluxes in soil (biogeochemistry of soils).
· who intend to complement their knowledge of plant or animal nutrition with that of soil nutrient availability.
· who will work in agriculture-related fields.
· who plan to do their thesis research or future work related to landuse in tropical countries.

The main aim of the course is to prepare students:

· to get familiar with the nutrient cycling in agro-ecosystems and the processes controlling nutrient availability in soil.
· to understand the difference between soil nutrient contents and their availability for plant growth.
· to develop approaches for soil fertility evaluation.
· to discuss the environmental impacts of agricultural landuse.

Course Contents

The course has three modules
Lecture
Seminar presentations (oral and poster presentation)
Laboratory (including a short oral presentation and a final paper)

Lecture (Tuesdays 8.40 to 9.55)

The goal of the lecture part of the course will be to introduce you to the basic information and principles of nutrient management and soil fertility. In addition we will discuss the flip side - environmental hazards from nutrient applications. Questions to be asked are: Which soil properties control nutrient availability? What soil nutrient pools must be assessed to evaluate resilience of soil fertility? How can we predict effects of inorganic and organic fertilizer applications on soil nutrient availability? How can we increase crop nutrient uptake and not pollute the environment?

· Information transfer
· Discussion (based on assignments)
· Guest speaker
· A final exam will be held on the topics covered by the lecture and the laboratory.

Seminar (Thursdays 8.40 to 9.55)

The seminar part of the course will give you the opportunity to develop your own ideas about nutrient management and explore the literature for ways to overcome soil fertility constraints. In this part, you will be dealing with soil management effects on fertility. An emphasis will be placed on innovative approaches (organic farming, modern soil preparation techniques) and whether they can live up to their promises.
One of the demands of the course is that you present your ideas in a coherent, convincing and interesting way. An important aspect of your performance is that you synthesize a large amount of information into simple messages which you convey to the audience with enthusiasm. Imagination is allowed!

· Seminar oral presentation
30 minutes, in groups of two=15 minutes each, topic related to laboratory procedure, e.g., Animal manure can substitute mineral fertilizer - fact or fiction? Does zero-till increase nutrient availability?) [draw conclusions from and summarize literature rather than quoting singular references; come up with a message] see topics
· Seminar poster [synthesize your presentation into a single poster; taking only the most important information; short presentation of the poster not exceeding 3 minutes]

Laboratory (Thursdays 1.25 to 4.25)

In the laboratory part of the course you will experience the link between soil fertility and plant growth and receive hands-on experience with analytical techniques. You will get to know the experimental challenges to characterize nutrient availability and not merely contents.
After choosing a topic you will develop an analytical program which gives you further insight into soil nutrient availability (sample topic: Which soil N fraction indicates soil degradation most sensitively?). We will analyze soils under different soil management systems and from all around the world. The experimental procedure will be designed according to scientific standards and likewise the data analyses and presentation in form of a research paper. In a short oral presentation at the end of the course you will be able to summarize your results (not more than 5 minutes and about 6 slides). The written paper will present the results of the laboratory study (not more than 8 pages; 12 point 1.5 line spacing; SSSAJ style). [Abstract, Introduction, Materials and Methods, Results, Discussion, Conclusions, References; introduce the topic in a concise way, leading to clear objectives; display the results neatly; discuss the results]

Experiments:
- Bioassay (soil fertility-plant growth and nutrition)
- Incubation (soil mineralization)

Analytical Methods:
- Plant nutrition
- Quality of organic matter additions (C, N)
- Mineral N
- P extractions
- P adsorption isotherms
- Soil "light fractions"
- Cation exchange capacity, acidity, pH

Grading

Point distribution:
Presentations/Poster (group score) 300
Presentation skills (individual score) 150
Final Paper 250
Final Exam 150
Participation 150
Total 1000

The grade will be based on the following scale:
1000 to 900 points (100 to 90 %) = A
899 to 800 points (89.9 to 80 %) = B
799 to 700 points (79.9 to 70 %) = C
699 to 600 points (69.9 to 60 %) = D
below 600 points (below 60 %) = F