Systems Theory
The term "systems" is derived from the Greek word "synistanai," which means "to bring together or combine." The term has been used for centuries. Components of the organizational concepts referred to as the "systems approach" have been used to manage armies and governments for millennia. However, it was not until the Industrial Revolution of the 19th and 20th centuries that formal recognition of the "systems" approach to management, philosophy, and science emerged (Whitehead 1925, von Bertalanffy 1968). As the level of precision and efficiency demanded of technology, science, and management increased the complexity of industrial processes, it became increasingly necessary to develop a conceptual basis to avoid being overwhelmed by complexity. The systems approach emerged as scientists and philosophers identified common themes in the approach to managing and organizing complex systems. Four major concepts underlie the systems approach:
Ecosystems are composed of elements and processes. (These are usually referred to as ecosystem structures and functions or the patterns and processes of an ecosystem.) As an example, the elements of a forest ecosystem might include trees, shrubs, herbs, birds, and insects, while the processes might include growth, mortality, decomposition, and disturbances.
Ecological systems are open systems with respect to most elements and processes. They receive energy and nutrient inputs from their physical environment and, at the same time, cycle nutrients back out of the system. They are also open to outside influences such as disturbances (e.g., hurricanes, ice storms, fires, insect outbreaks).
Most systems contain nested systems; that is, subsystems within the system. Similarly, many systems are subsystems of larger systems. |
For example, the nested system above right could represent:
atoms (black dots), molecules (red circles), cells (blue), and organs (green);
leaves (black dots), trees (red circles), stands (blue), and landscapes (green);
planets (black dots), solar systems (red circles), galaxies (blue circle), and universes (green).
Nested systems can be considered as a hierarchy of systems. Hierarchical (nested) systems contain both parallel components (polygons of the same color, above) and sequential components (polygons of different colors, above).
"At the higher levels, you get a more abstract, encompassing view of the whole emerges, without attention to the details of the components or parts. At the lower level, you see a multitude of interacting parts but without understanding how they are organized to form a whole (Principia Cybernetica 1999)."
Attempting to measure, study,
or manage a system at a precision greater than the innate variation
among its components leads to meaningless measures. At the upper
levels of a hierarchical system, the amount of precision which
can be measured, studied, or managed declines for two reasons:
Moving information between levels of a hierarchy requires time. The variation in time needed to process different steps within a hierarchy can lead to innate temporal lags or bottlenecks. These can be minimized by not trying to consider a system with high precision from a single, central, upper hierarchical level (e.g., centralized planning by governments or regional models of ecosystems). Instead, such centralized levels are useful for generalities which allow local variation, while more precision is achieved through independent, parallel processes at more localized levels.