Objective: Finding and discussing pros and cons arguments as wells as investigating effects and retrospectivity.
Learning outcomes: Learners are able to identify problems and discuss them in a pros and cons argumentation. They are able to develop solutions to problems as well as to develop a field study and a laboratory experiment.
Previous knowledge: Firm text apprehension
Duration: Approx. 60 min
Materials / Conditions: Introduction
Methods / Techniques: Written essay and creative thinking
Learning subject: Biodiversity / Module 3: Collection and Analysis of Biodiversity Data / Level: expert learning
On the Cabo Verde islands, in the west of Africa, the following problem is present: soil and vegetation are permanently affected by extensively grazing goats. The impacts include, for instance, damages from treading animals, resulting in erosion through wind and water or a weakening of the vegetation through continuous eating away at buds. However, goats are important as agricultural cattle for Cabo Verde’s inhabitants.
Negative effects from grazing goats become explicitly visible within the following experiment: There are two different open spaces. One features grazing goats, introduced by man, thereby actively interfering with nature- this depicts a laboratory experiment. The other green space is in a „natural condition“ i.e., it’s not used for agricultural purposes – this is called a field study. One can notice a difference in plant diversity between the two areas: The one which is used for agriculture features a lower plant diversity than the other one.
(Extract and translation taken from: Leyens T. (2001): Biodiversität des geplanten Schutzgebietes auf der Insel Fogo/ Kap Verde. Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbH; Eschborn. Portugiesische Ausgabe: Leyens, T. (2001): Biodiversidade da prevista área protegida na Ilha do Fogo, Cabo Verde)
a) Discuss the problem presented above with a pros and cons essay. Use the information provided but also think beyond: are there effects of the effects? How do the inhabitants profit from keeping goats etc.?
b) Find solutions to the problem.
c) Develop another field study and laboratory experiment based on the definitions given below. You are not bound to the topic of extensively grazing goats, be creative and explain why your experiment is a field study/ a laboratory experiment.
In a laboratory experiment an artificial situation is created by a human. It does not necessarily have to take place within a laboratory, the term only states that the experiment takes place without any outer influence. This means the research items are isolated.
In a field study, the test subject or test object remains within his/her/its natural environment i.e. the experiment takes place without any human influence.
Possible results / Results:
Pros: staple food, economic factor, no additional work through fencing, no additional fodder needed for goats as they feed on grass
Cons: Reduced biodiversity, damages from treading goats, erosion, feeding damage
- Possible solutions: allowing goats on fenced areas only, paying attention to soil regeneration, letting goats graze only where there are no/little endangered plant species
- Coming up with a field study and a laboratory experiment and explaining it with the help of the information provided
Author: Leonie Muy and Sandra Schöffer
Aus dem Deutschen übersetzt von Jana Prokaka