9.3 A Canon of QuestlOns
233
In order to give a homogeneous, unifying structure to the discussion of the ingredients of the Wadden Sea, the following canon of questions will be addressed
wherever possible:
(J) At what level of description and with what variables of interest is the
ingredient considered?
In principle, an unlimited number of levels of description and, in particular, variables of interest could be used to characterize a certain system (Hall & DeAngelis
1985). The level of description and variables of interest actually used are often
determined by methodological limits, as well as by the scale of human perception.
Bacteria, for example, are described in much less detail than, for example, macfOzoobenthic species (Fenchel 1992).
(2) What is the significance of the ingredient with respect to the dynamics of the
Wadden Sea?
This question is designed to identify the elements of an integrated view of the
Wadden Sea; it targets interactions between the ingredient and the Wadden Sea or
other ingredients. Aspects which are only relevant at the level of the ingredient
will not be discussed.
(3) What are the results of the assessments of constancy, persistence, resilience,
and (ifpossible) resistance?
First of all, stability properties are considered which can be assessed without reference to disturbances, i.e. constancy and persistence. Resilience can only be assessed if there is some idea about the reference dynamics (see "ecological checklist" above). The task is then to characterize the reaction to certain disturbances.
Resistance will only be discussed in exceptional cases.
(4) What mechanisms, processes and structures are relevant to the stability
properties?
Understanding stability mechanisms is the main concern during the discussion of
the stability properties of the ingredients. Therefore we will primarily concentrate
our efforts on answering this question.
(5) Extreme scenarios: What would the Wadden Sea look like if the ingredient
lost its stability properties?
Like question (2), the aim behind this question is to understand the interactions
between the ingredient and the whole system. Once the extreme scenarios have
been discussed, we will discuss the mechanisms which prevented these scenarios
in the past and try to assess the probability that they will continue to do so in the
future. However, this does not mean that we will define any precise tolerance limits as this would present a machine-like and therefore inappropriate view of the
Wadden Sea.
233
In order to give a homogeneous, unifying structure to the discussion of the ingredients of the Wadden Sea, the following canon of questions will be addressed
wherever possible:
(J) At what level of description and with what variables of interest is the
ingredient considered?
In principle, an unlimited number of levels of description and, in particular, variables of interest could be used to characterize a certain system (Hall & DeAngelis
1985). The level of description and variables of interest actually used are often
determined by methodological limits, as well as by the scale of human perception.
Bacteria, for example, are described in much less detail than, for example, macfOzoobenthic species (Fenchel 1992).
(2) What is the significance of the ingredient with respect to the dynamics of the
Wadden Sea?
This question is designed to identify the elements of an integrated view of the
Wadden Sea; it targets interactions between the ingredient and the Wadden Sea or
other ingredients. Aspects which are only relevant at the level of the ingredient
will not be discussed.
(3) What are the results of the assessments of constancy, persistence, resilience,
and (ifpossible) resistance?
First of all, stability properties are considered which can be assessed without reference to disturbances, i.e. constancy and persistence. Resilience can only be assessed if there is some idea about the reference dynamics (see "ecological checklist" above). The task is then to characterize the reaction to certain disturbances.
Resistance will only be discussed in exceptional cases.
(4) What mechanisms, processes and structures are relevant to the stability
properties?
Understanding stability mechanisms is the main concern during the discussion of
the stability properties of the ingredients. Therefore we will primarily concentrate
our efforts on answering this question.
(5) Extreme scenarios: What would the Wadden Sea look like if the ingredient
lost its stability properties?
Like question (2), the aim behind this question is to understand the interactions
between the ingredient and the whole system. Once the extreme scenarios have
been discussed, we will discuss the mechanisms which prevented these scenarios
in the past and try to assess the probability that they will continue to do so in the
future. However, this does not mean that we will define any precise tolerance limits as this would present a machine-like and therefore inappropriate view of the
Wadden Sea.