replace the dotted circle because there is no reason to exclude any of
the organizations shown outside the dotted circle. If any number of com-
ponents other than the links of the chain could be inside the boundary,
usually called the postharvest system, then it would not be possible to
distinguish between components inside or outside the arbitrary bound-
ary. It will be shown that each link meets the requirements for being a
system, including the ability to draw a boundary separating the compo-
nent parts in the link from other links in the chain and from the organi-
zations in the environment (suppliers, banks, etc.).
The wide range of possible chains presented in the peach example
demonstrate that food chains frequently form and disperse. Thus, the re-
quirement that a system have continuity (item 9) is not satisfied.
Recognizing that food chains are not systems helps to understand why
it is difficult to make changes that promise to reduce losses or improve
the quality of products available to consumers. A change typically cost
money and there is no authority outside the chain that can require that
higher profits for one link are transferred to another link that made the
investment. Similarly, it is difficult to obtain research funding to im-
prove the chain because there is not a funding source (other than some
government agencies) that takes responsibility for all the links or more
general priorities. Thus, research tends to focus on improving only one
business link.
Links Are Systems
Each link shown in Figure 14.1 meets all nine of the requirements to
be viewed as a system. Consider the consumer system (link).
- The consumer has the ongoing purpose of selecting, purchasing, and
consuming fresh fruit. - Performance of the system is measured by how satisfied the con-
sumer (system owner) is with the availability, price, and quality of
the peach. - Decisions are made on where to purchase, how much to pay, and
level of satisfaction. - Subsystems for the consumer system include activities to obtain, store,
prepare, and eat fruit along with the need to manage the system. - The subsystems interact.
- The consumer interacts with a wider environment.
Examples of Visual Models 275